title: Pulmonary vein antral isolation using an open irrigation ablation catheter for the treatment of atrial fibrillation: a randomized pilot study. Atrial Fibrillation Ablation in Patients With Therapeutic International Normalized Ratio: Comparison of Strategies of Anticoagulation Management in the Periprocedural Period Technique and Results of Linear Ablation at the Mitral Isthmus Efficacy of adjuvant anterior left atrial ablation during intracardiac echocardiography-guided pulmonary vein antrum isolation for atrial fibrillation. A randomized prospective comparison of CartoMerge and CartoXP to guide circumferential pulmonary vein isolation for the treatment of paroxysmal atrial fibrillation. Substrate modification combined with pulmonary vein isolation improves outcome of catheter ablation in patients with persistent atrial fibrillation: a prospective randomized comparison. Changes in Atrial Fibrillation Cycle Length and Inducibility During Catheter Ablation and Their Relation to Outcome Effect of the statistical significance of results on the time to completion and publication of randomized efficacy trials. Randomized Study Comparing Combined Pulmonary Vein–Left Atrial Junction Disconnection and Cavotricuspid Isthmus Ablation Versus Pulmonary Vein–Left Atrial Junction Disconnection Alone in Patients Presenting With Typical Atrial Flutter and Atrial Fibrillation Techniques, evaluation, and consequences of linear block at the left atrial roof in paroxysmal atrial fibrillation: a prospective randomized study. Small or Large Isolation Areas Around the Pulmonary Veins for the Treatment of Atrial Fibrillation?: Results From a Prospective Randomized Study Role of anticoagulation therapy after pulmonary vein antrum isolation for atrial fibrillation treatment Evaluation of an individualized strategy of cavotricuspid isthmus ablation as an adjunct to atrial fibrillation ablation. Radiofrequency ablation vs antiarrhythmic drugs as first-line treatment of symptomatic atrial fibrillation: a randomized trial. Randomized comparison of encircling and nonencircling left atrial ablation for chronic atrial fibrillation. Pulmonary vein isolation for the treatment of atrial fibrillation in patients with impaired systolic function. Characteristics of patients undergoing atrial fibrillation ablation: trends over a seven-year period 1999-2005. Long-term single procedure efficacy of catheter ablation of atrial fibrillation Prevention of Iatrogenic Atrial Tachycardia After Ablation of Atrial Fibrillation: A Prospective Randomized Study Comparing Circumferential Pulmonary Vein Ablation With a Modified Approach Pulmonary vein isolation and linear lesions in atrial fibrillation ablation Catheter Ablation Versus Antiarrhythmic Drugs for Atrial Fibrillation: The A4 Study Catheter Ablation for Paroxysmal Atrial Fibrillation: Segmental Pulmonary Vein Ostial Ablation Versus Left Atrial Ablation Is circumferential pulmonary vein isolation preferable to stepwise segmental pulmonary vein isolation for patients with paroxysmal atrial fibrillation? Single procedure efficacy of isolating all versus arrhythmogenic pulmonary veins on long-term control of atrial fibrillation: a prospective randomized study. The effectiveness of a high output/short duration radiofrequency current application technique in segmental pulmonary vein isolation for atrial fibrillation. Relationships Between Sinus Rhythm, Treatment, and Survival in the Atrial Fibrillation Follow-Up Investigation of Rhythm Management (AFFIRM) Study Segmental pulmonary vein ablation: success rates with and without exclusion of areas adjacent to the esophagus. Gender-related differences in catheter ablation of atrial fibrillation. The impact of image integration on catheter ablation of atrial fibrillation using electroanatomic mapping: a prospective randomized study. Circumferential pulmonary-vein ablation for chronic atrial fibrillation. Noninducibility of Atrial Fibrillation as an End Point of Left Atrial Circumferential Ablation for Paroxysmal Atrial Fibrillation: A Randomized Study Freedom From Atrial Tachyarrhythmias After Catheter Ablation of Atrial Fibrillation: A Randomized Comparison Between 2 Current Ablation Strategies Phased-Array Intracardiac Echocardiography Monitoring During Pulmonary Vein Isolation in Patients With Atrial Fibrillation: Impact on Outcome and Complications Clinical implications of reconnection between the left atrium and isolated pulmonary veins provoked by adenosine triphosphate after extensive encircling pulmonary vein isolation. Computed tomography-fluoroscopy image integration-guided catheter ablation of atrial fibrillation. Left mitral isthmus ablation associated with PV Isolation: long-term results of a prospective randomized study. Segmental pulmonary vein antrum isolation using the "large-size" lasso catheter in patients with atrial fibrillation. Is inducibility of atrial fibrillation after radio frequency ablation really a relevant prognostic factor? Electrophysiologic and anatomic characterization of sites resistant to electrical isolation during circumferential pulmonary vein ablation for atrial fibrillation: a prospective study. Catheter ablation treatment in patients with drug-refractory atrial fibrillation: a prospective, multi-centre, randomized, controlled study (Catheter Ablation For The Cure Of Atrial Fibrillation Study). Mortality, morbidity, and quality of life after circumferential pulmonary vein ablation for atrial fibrillation: outcomes from a controlled nonrandomized long-term study. Electrical isolation of pulmonary veins in patients with atrial fibrillation: reduction of fluoroscopy exposure and procedure duration by the use of a non-fluoroscopic navigation system (NavX). Catheter Ablation to Suppress Atrial Fibrillation: Evolution of Technique at a Single Center Transcranial Doppler detection of microembolic signals during pulmonary vein antrum isolation: implications for titration of radiofrequency energy. Pulmonary vein vestibule ablation for the control of atrial fibrillation in patients with impaired left ventricular function. Predictive value of early recurrence and delayed cure after catheter ablation for patients with chronic atrial fibrillation. Randomized comparison between open irrigation technology and intracardiac-echo-guided energy delivery for pulmonary vein antrum isolation: procedural parameters, outcomes, and the effect on esophageal injury. Left atrial ablation versus biatrial ablation for persistent and permanent atrial fibrillation: a prospective and randomized study. A randomized trial of circumferential pulmonary vein ablation versus antiarrhythmic drug therapy in paroxysmal atrial fibrillation: the APAF Study. Comparison between anatomical and integrated approaches to atrial fibrillation ablation: adjunctive role of electrical pulmonary vein disconnection. Clinical predictors of noninducibility of sustained atrial fibrillation after pulmonary vein isolation. Early complications of pulmonary vein catheter ablation for atrial fibrillation: a multicenter prospective registry on procedural safety. Achievement of pulmonary vein isolation in patients undergoing circumferential pulmonary vein ablation: a randomized comparison between two different isolation approaches. The impact of CT image integration into an electroanatomic mapping system on clinical outcomes of catheter ablation of atrial fibrillation. Catheter Ablation for Atrial Fibrillation in Patients With Obesity Antiarrhythmic drug therapy after radiofrequency catheter ablation in patients with atrial fibrillation. Reduction of fluoroscopy exposure and procedure duration during ablation of atrial fibrillation using a novel anatomical navigation system. Comparison of cool tip versus 8-mm tip catheter in achieving electrical isolation of pulmonary veins for long-term control of atrial fibrillation: a prospective randomized pilot study. Cooled-tip vs. 8 mm-tip catheter for circumferential pulmonary vein ablation: comparison of efficacy, safety, and lesion extension. Is empirical four pulmonary vein isolation necessary for focally triggered paroxysmal atrial fibrillation? Comparison of selective pulmonary vein isolation versus empirical four pulmonary vein isolation. Catheter ablation for atrial fibrillation in congestive heart failure. A comparison of rate control and rhythm control in patients with atrial fibrillation. Electrical isolation of the superior vena cava: an adjunctive strategy to pulmonary vein antrum isolation improving the outcome of AF ablation. Pulmonary vein isolation combined with superior vena cava isolation for atrial fibrillation ablation: a prospective randomized study. A new nonfluoroscopic navigation system to guide pulmonary vein isolation. Radiofrequency ablation of drug-refractory atrial fibrillation: an observational study comparing 'ablate and pace' with pulmonary vein isolation. Recurrence of pulmonary vein conduction and atrial fibrillation after pulmonary vein isolation for atrial fibrillation: a randomized trial of the ostial versus the extraostial ablation strategy. A randomized clinical trial of the efficacy of radiofrequency catheter ablation and amiodarone in the treatment of symptomatic atrial fibrillation. Efficacy and safety of segmental ostial versus circumferential extra-ostial pulmonary vein isolation for atrial fibrillation. Early identification and treatment of PV re-connections: role of observation time and impact on clinical results of atrial fibrillation ablation. Safety and efficacy of catheter ablation of atrial fibrillation in patients with diabetes mellitus—single center experience
abstract: OBJECTIVES We sought to test how catheter ablation using an open irrigation catheter ( OIC ) compares with st and ard catheters for pulmonary vein antrum isolation . BACKGROUND Open irrigation catheters have the advantage of delivering greater power without increasing the temperature of the catheter tip , which enables deeper and wider lesions without the formation of coagulum on catheters . METHODS Catheter ablation was performed using an 8-mm catheter ( 8MC ) or an OIC .  Patients were r and omized to 3 groups : 8MC ; OIC-1 , OIC with a higher peak power ( 50 W ) ; and OIC-2 , OIC with lower peak power ( 35 W ) . RESULTS A total of 180 patients were r and omized to the 3 treatment strategies .  Isolation of pulmonary vein antra was achieved in all patients . The freedom from atrial fibrillation was significantly greater in the 8MC and OIC-1 groups compared with the OIC-2 group ( 78 % , 82 % , and 68 % , respectively , p = 0.043 ) . Fluoroscopy time was lower in OIC-1 compared with OIC-2 and 8MC ( 28 + /- 1 min , 53 + /- 2 min , and 46 + /- 2 min , respectively , p = 0.001 ) . The mean left atrium instrumentation time was lower in the OIC-1 compared with the OIC-2 and 8MC groups ( 59 + /- 3 min , 90 + /- 5 min , and 88 + /- 4 min , respectively , p = 0.001 ) . However , there was a greater incidence of " pops " in the OIC-1 ( 100 % , 0 % , 0 % , p < 0.001 ) along with higher incidences of pericardial effusion ( 20 % , 0 % , 0 % , p < 0.001 ) and gastrointestinal complaints ( 17 % in OIC-1 , 3 % in 8MC , and 5 % in OIC-2 , p = 0.031 ) . CONCLUSIONS Although there was a decrease in fluoroscopy and left atrium instrumentation time with the use of OIC at higher power , this setting was associated with increased cardiovascular and gastrointestinal complications Background — The best approach to management of anticoagulation before and after atrial fibrillation ablation is not known . Methods and Results — We compared outcomes in consecutive patients undergoing pulmonary vein antrum isolation for persistent atrial fibrillation . Early in our practice , warfarin was stopped 3 days before ablation , and a transesophageal echocardiogram was performed to rule out clot . Enoxaparin , initially 1 mg/kg twice daily ( group 1 ) and then 0.5 mg/kg twice daily ( group 2 ) , was used to “ bridge ” patients after ablation . Subsequently , warfarin was continued to maintain the international normalized ratio between 2 and 3.5 ( group 3 ) . Minor bleeding was defined as hematoma that did not require intervention . Major bleeding was defined as either cardiac tamponade , hematoma that required intervention , or bleeding that required blood transfusion .  Pulmonary vein ablation was performed in 355 patients ( group 1=105 , group 2=100 , and group 3=150 ) . More patients had spontaneous echocardiographic contrast in groups 1 and 2 . One patient in group 1 had an ischemic stroke compared with 2 patients in group 2 and no patients in group 3 . In group 1 , 23 patients had minor bleeding , 9 had major bleeding , and 1 had pericardial effusion but no tamponade . In group 2 , 19 patients had minor bleeding , and 2 patients developed symptomatic pericardial effusion with need for pericardiocentesis 1 week after discharge . In group 3 , 8 patients developed minor bleeding , and 1 patient developed pericardial effusion with no tamponade . Conclusions — Continuation of warfarin throughout pulmonary vein ablation without administration of enoxaparin is safe and efficacious . This strategy can be an alternative to bridging with enoxaparin or heparin in the periprocedural period Background —This prospect i ve clinical study evaluates the feasibility and efficacy of combined linear mitral isthmus ablation and pulmonary vein ( PV ) isolation in patients with paroxysmal atrial fibrillation ( AF ) . Methods and Results —One hundred consecutive patients ( 13 women ; age 55±10 years ) with drug-refractory , symptomatic paroxysmal AF underwent PV isolation and linear ablation of the cavotricuspid isthmus and the mitral isthmus ( lateral mitral annulus to the left inferior PV ) . They were compared with 100 consecutive patients ( 14 women ; age , 52±10 years ) undergoing PV isolation and cavotricuspid ablation without mitral isthmus ablation .  Bidirectional mitral isthmus block was confirmed by demonstrating ( 1 ) a parallel corridor of double potentials during coronary sinus ( CS ) pacing , ( 2 ) an activation detour by pacing either side of the line , and ( 3 ) differential pacing techniques . Isolation of all PVs and cavotricuspid isthmus ablation were performed successfully in all . Mitral isthmus block was achieved in 92 patients after 20±10 minutes of endocardial radiofrequency application and an additional 5±4 minutes of epicardial radiofrequency application from within the CS in 68 , result ing in a conduction delay of 151±26 ms during CS pacing . Thirty-two patients with mitral isthmus ablation compared with 49 without had recurrent atrial arrhythmia ( P=0.02 ) requiring further ablation . At 1 year after the last procedure , 87 patients with mitral isthmus ablation and 69 without ( P=0.002 ) were arrhythmia free without antiarrhythmic drugs , mitral isthmus ablation being the only factor associated with long-term success ( RR for AF recurrence , 0.2 ; CI , 0.1 to 0.4 ; P<0.001 ) . Conclusions —Catheter ablation of the mitral isthmus results consistently in demonstrable conduction block and is associated with a high cure rate for paroxysmal AF BACKGROUND Recent data have shown that the septum and anterior left atrial ( LA ) wall may contain " rotor " sites required for AF maintenance . However , whether adding ablation of such sites to st and ard ICE-guided PVAI improves outcome is not well known . OBJECTIVE To determine if adjuvant anterior LA ablation during PVAI improves the cure rate of paroxysmal and permanent AF . METHODS One hundred AF patients ( 60 paroxysmal , 40 persistent/permanent ) undergoing first-time PVAI were enrolled over three months to receive adjuvant anterior LA ablation ( Group I ) . These patients were compared with 100 r and omly selected , matched first-time PVAI controls from the preceding three months who did not receive adjuvant ablation ( Group II ) . All 200 patients underwent ICE-guided PVAI during which all four PV antra and SVC were isolated . In group I , a decapolar lasso catheter was used to map the septum and anterior LA wall during AF ( induced or spontaneous ) for continuous high-frequency , fractionated electrograms ( CFAE ) . Sites where CFAE were identified were ablated until the local EGM was eliminated . A complete anterior line of block was not a requisite endpoint . Patients were followed up for 12 months . Recurrence was assessed post-PVAI by symptoms , clinic visits , and Holter at 3 , 6 , and 12 months . Patients also wore rhythm transmitters for the first 3 months . Recurrence was any AF/AFL > 1 min occurring > 2 months post-PVAI . RESULTS Patients ( age 56 + /- 11 years , 37 % female , EF 53%+/- 11 % ) did not differ in baseline characteristics between group I and II by design . Group I patients had longer procedure time ( 188 + /- 45 min vs 162 + /- 37 min ) and RF duration ( 57 + /- 12 min vs 44 + /- 20 min ) than group II ( P < 0.05 for both ) . Overall recurrence occurred in 15/100 ( 15 % ) in group I and 20/100 ( 20 % ) in group II ( P = 0.054 ) . Success rates did not differ for paroxysmal patients between group I and II ( 87 % vs 85 % , respectively ) . However , for persistent/permanent patients , group I had a higher success rate compared with group II ( 82 % vs 72 % , P = 0.047 ) . CONCLUSIONS Adjuvant anterior LA ablation does not appear to impact procedural outcome in patients with paroxysmal AF but may offer benefit to patients with persistent/permanent AF BACKGROUND CartoXP and CartoMerge have been used to treat atrial fibrillation ( AF ) for several years . Our r and omized prospect i ve study compared clinical outcomes of these two versions of three dimensional electroanatomic mapping system in guiding catheter ablation for paroxysmal atrial fibrillation ( PAF ) . METHODS Eighty-one patients with symptomatic , drug refractory PAF were r and omly assigned to  CartoMerge group ( n=42 , mean age ( 54.5+/-13.1 ) years , history of AF=3.2 years ) or CartoXP group ( n=39 , mean age ( 59.8+/-15.6 ) years , history of AF = 2.9 years ) . All patients underwent 64-slice computed tomography ( MSCT ) 1 to 3 days prior to ablation procedure . Using CartoMerge(TM ) Image Integration Module , 3D anatomical images of the left atrium ( LA ) and pulmonary veins ( PVs ) derived from MSCT of CartoMerge group were established and merged with the electroanatomical map . The integrated images were used to guide the procedure of circumferential pulmonary vein isolation ( CPVI ) . In the other group , CPVI was guided just by CartoXP . The endpoint of CPVI in both groups was abolition or dissociation of pulmonary vein potentials ( PVPs ) . RESULTS Mapping points to establish the electroanatomical model of the LA/PVs were 48.7+/-13.4 in CartoMerge group and 62.5+/-15.7 in CartoXP group ( P<0.001 ) . Mean distance between mapping points and the MSCT surfaces in CartoMerge group was ( 1.59+/-0.33 ) mm . Accomplishment of abolition or dissociation of PVPs was achieved 95.2 % in CartoMerge group and 92.3 % in CartoXP group . Duration s of procedure and exposure to X-ray were ( 156+/-25 ) minutes , ( 179+/-21 ) minutes ( P<0.001 ) and ( 19.6+/-7.5 ) minutes , ( 28.5+/-12.8 ) minutes ( P<0.001 ) , respectively . After a follow-up with duration of ( 11.9+/-3.1 ) months vs ( 12.4+/-3.6 ) months post the first ablation procedure , patients free of AF were 33 ( 78.6 % ) in CartoMerge group and 29 ( 74.4 % ) in CartoXP group ( P>0.50 ) . No patient suffered pulmonary vein stenosis , atrioesophageal fistula , stroke or death . CONCLUSION Compared to CartoXP , CartoMerge shortened the catheter ablation procedure and exposure to X-ray , without affecting the clinical outcomes of circumferential pulmonary vein isolation for the treatment of paroxysmal atrial fibrillation in experienced centres AIMS To investigate the effectiveness of additional substrate modification ( SM ) by left atrial ( LA ) linear lesions as compared with pulmonary vein isolation ( PVI ) alone in patients with persistent atrial fibrillation ( AF ) in a prospect i ve r and omized study . Percutaneous PVI has evolved as an accepted treatment for paroxysmal AF but seemed to be less effective in patients with persistent AF . The benefit of PVI alone and additional linear lesions has not been vali date d in a r and omized study so far . METHODS AND RESULTS Sixty-two patients with persistent AF ( median duration 7 , range 1 - 18 months ) were r and omly assigned to either PVI alone ( n = 30 ) or additional SM ( n = 32 ) consisting of a roof line connecting both left superior and right superior PV and LA isthmus ablation between left inferior PV and mitral annulus . Procedures including SM were performed using a three-dimensional mapping system ( EnSite NavX , St Jude Medical , St Paul , MN , USA ) . Anti-arrhythmic drugs were discontinued within 8 weeks after ablation in both groups . Follow-up included daily trans-telephonic ECG transmitted irrespective of the patient 's symptoms . PVI was successful in 98 % of all targeted veins in both groups . Additional SM did not increase fluoroscopy time ( 72.1+/-18.7 vs. 72.9+/-17.3 min , P=0.92 ) because of the use of three-dimensional navigation in the PVI+SM group . AF recurrences within the first 4 weeks following ablation were more common after PVI alone ( 77 % ) than additional SM ( 44 % , P=0.002 ) . After a follow-up time of 487 ( 429 - 570 ) days , only 20 % of patients undergoing st and alone PVI  remained in sinus rhythm when compared with 69 % following PVI combined with SM ( P=0.0001 ) . Two patients assigned to PVI+SM experienced procedure-related complications ( cardiac tamponade and minor stroke ) which resolved without sequelae . CONCLUSION PVI alone is insufficient in the treatment of persistent AF . However , additional left linear lesions increase the success rate significantly . Early AF-relapses are associated with a negative outcome after PVI alone but not following additional SM Background —The modification of atrial fibrillation cycle length ( AFCL ) during  catheter ablation in humans has not been evaluated . Methods and Results —Seventy patients undergoing ablation of prolonged episodes of AF were r and omized to pulmonary vein ( PV ) isolation or additional ablation of the mitral isthmus .  Mean AFCL was determined at a distance from the ablated area ( coronary sinus ) at the following intervals : before ablation , after 2- and 4-PV isolations , and after linear ablation . Inducibility of sustained AF ( ≥10 minutes ) was determined before and after ablation . Spontaneous sustained AF ( 715±845 minutes ) was present in 30 patients and induced in 26 ( AFCL , 186±19 ms ) . PV isolation terminated AF in 75 % , with the number of PVs requiring isolation before termination increasing with AF duration ( P = 0.018 ) . PV isolation result ed in progressive or abrupt AFCL prolongation to various extents , depending on the PV : to 214±24 ms ( P < 0.0001 ) when AF terminated and to 194±19 ms ( P < 0.002 ) when AF persisted . The increase in AFCL ( 30±17 versus 14±11 ms ; P = 0.005 ) and the decrease in fragmentation ( 30.0±26.8 % to 10.3±14.5 % ; P < 0.0001 ) were significantly greater in patients with AF termination . Linear ablation prolonged AFCL , with a greater prolongation in patients with AF termination ( 44±13 versus 22±23 ms ; P = 0.08 ) . Sustained AF was noninducible in 57 % after PV isolation and in 77 % after linear ablation . At 7±3 months , 74 % with PV isolation and 83 % with linear ablation were arrhythmia free without antiarrhythmics , which was significantly associated with noninducibility ( P = 0.03 ) with a recurrence rate of 38 % and 13 % in patients with and without inducibility , respectively . Conclusions —AF ablation results in a decline in AF frequency , with a magnitude correlating with termination of AF and prevention of inducibility that is predictive of subsequent clinical outcome CONTEXT Medical evidence may be biased over time if completion and publication of r and omized efficacy trials are delayed when results are not statistically significant . OBJECTIVE To evaluate whether the time to completion and the time to publication of r and omized phase 2 and phase 3 trials are affected by the statistical significance of results and to describe the natural history of such trials . DESIGN Prospect i ve cohort of r and omized efficacy trials conducted by 2 trialist groups from 1986 to 1996 . SETTING Multicenter trial groups in human immunodeficiency virus infection sponsored by the National Institutes of Health . PATIENTS A total of 109 efficacy trials ( total enrollment , 43708 patients ) . MAIN OUTCOME MEASURES Time from start of enrollment to completion of follow-up and time from completion of follow-up to peer- review ed publication assessed with survival analysis . RESULTS The median time from start of enrollment to publication was 5.5 years and was substantially longer for negative trials than for results favoring an experimental arm ( 6.5 vs 4.3 years , respectively ; P<.001 ; hazard ratio for time to publication for positive vs negative trials , 3.7 ; 95 % confidence interval [ CI ] , 1.8 - 7.7 ) . This difference was mostly attributable to differences in the time from completion to publication ( median , 3.0 vs 1.7 years for negative vs positive trials ; P<.001 ) . On average , trials with significant results favoring any arm completed follow-up slightly earlier than trials with nonsignificant results ( median , 2.3 vs 2.5 years ; P=.045 ) , but long-protracted trials often had low event rates and failed to reach statistical significance , while trials that were terminated early had significant results . Positive trials were su bmi tted for publication significantly more rapidly after completion than were negative trials ( median , 1.0 vs 1.6 years ; P=.001 ) and were published more rapidly after su bmi ssion ( median , 0.8 vs 1.1 years ; P=.04 ) . CONCLUSION Among r and omized efficacy trials , there is a time lag in the publication of negative findings that occurs mostly after the completion of the trial follow-up Background —Atrial flutter ( AFL ) and atrial fibrillation ( AF ) frequently coexist in the same patient . Recently it has been demonstrated that the triggers for both AF and AFL may originate in the pulmonary veins ( PVs ) . We hypothesized that in patients with both AF and typical AFL , pulmonary vein – left atrial junction ( PV-LAJ ) disconnection may eliminate both arrhythmias . Methods and Results —Consecutive patients with documented symptomatic AF and typical AFL were r and omly assigned to have PV-LAJ disconnection combined with cavotricuspid isthmus ( CTI ) ablation ( group 1 , n=49 ) or PV-LAJ disconnection alone ( group 2 , n=59 ) . Within the first 8 weeks after ablation , 32 of the group 2 patients had typical AFL documented , whereas none was seen in group 1 . Twenty of these 32 converted to sinus rhythm after initiating antiarrhythmic drugs ( AADs ) . Twelve were cardioverted , and AADs were started . After 8 weeks , all AADS were stopped , and only 3 patients continued to have recurrent sustained typical AFL that was eliminated by CTI ablation . Beyond 8 weeks of follow-up , 7 patients in group 1 and 6 patients in group 2 ( 14 % and 11 % , respectively ) continued to have AF . Ten of these 13 patients underwent a repeat PV-LAJ disconnection procedure and were cured . The remaining 3 remained in normal sinus rhythm while taking AADs . Conclusions —In patients with both AFL and AF , PV-LAJ disconnection alone may be sufficient to control both arrhythmias . CTI block reduced early postablation recurrence of arrhythmias , which in the majority of patients reflects a short-term clinical problem BACKGROUND There are no reports describing the technique , electrophysiological evaluation , and clinical consequences of complete linear block at roofline joining the superior pulmonary veins ( PVs ) in patients with paroxysmal atrial fibrillation ( AF ) . METHODS AND RESULTS Ninety patients with drug-refractory paroxysmal AF undergoing radiofrequency ablation  were prospect ively r and omized into 2 ablation strategies : ( 1 ) PV isolation ( n=45 ) or ( 2 ) PV isolation in combination with linear ablation joining the 2 superior PVs ( roofline ; n=45 ) . In both groups , the cavotricuspid isthmus , fragmented peri-PV-ostial electrograms , and spontaneous non-PV foci were ablated . Roofline ablation was performed at the most cranial part of the left atrium ( LA ) with complete conduction block demonstrated during LA appendage pacing by the online mapping of continuous double potential and an activation detour propagating around the PVs to activate caudocranially the posterior wall of the LA . The effect of ablation at the LA roof was evaluated by the change in fibrillatory cycle length , termination and noninducibility of AF , and clinical outcome . PV isolation was achieved in all patients with no significant differences in the radiofrequency duration , fluoroscopy , or procedural time between the groups . Roofline ablation required 12+/-6 ( median 11 , range 3 to 25 ) minutes of radiofrequency energy delivery with a fluoroscopic duration of 7+/-2 minutes and was performed in 19+/-7 minutes . Complete block was confirmed in 43 patients ( 96 % ) and result ed in an activation delay that was shorter circumventing the left than the right PVs during LA appendage pacing ( 138+/-15 versus 146+/-25 ms , respectively ; P=0.01 ) . Roofline ablation result ed in a significant increase in the fibrillatory cycle length ( 198+/-38 to 217+/-44 ms ; P=0.0005 ) , termination of arrhythmia in 47 % ( 8/17 ) , and subsequent noninducibility of AF in 59 % ( 10/17 ) of the patients inducible after PV isolation . However , LA flutter , predominantly perimitral , could be induced in 10 patients ( 22 % ) after roofline ablation . At 15+/-4 months , 87 % of the roofline group and 69 % with PV isolation alone are arrhythmia free without antiarrhythmics ( P=0.04 ) . CONCLUSIONS This prospect i ve r and omized study demonstrates the feasibility of achieving complete linear block at the LA roof . Such ablation result ed in the prolongation of the fibrillatory cycle , termination of AF , and subsequent noninducibility and is associated with an improved clinical outcome compared with PV isolation alone Background — Pulmonary vein ( PV ) isolation is a promising new treatment for  atrial fibrillation ( AF ) . We hypothesized that isolation of large areas around both ipsilateral PVs with verification of conduction block is more effective than the isolation of each individual PV . Methods and Results — A total of 110 patients , 67 with paroxysmal AF and 43 with persistent AF , were r and omly assigned to undergo either isolation of each individual PV or isolation of large areas around both ipsilateral PVs . The isolation of each individual PV was an electrophysiologically guided , ostial segmental ablation with a 64-pole basket catheter or a 20-pole circular mapping catheter ( group I ) . Isolation of large areas was performed around the 2 ipsilateral veins with a nonfluoroscopic navigation system and a circular 20-pole mapping catheter for verification of conduction block ( group II ) . In both groups , an irrigated-tip ablation catheter ( 25 to 35 W ) was used to achieve complete isolation . Procedure and ablation times were longer in group II , whereas fluoroscopic time was significantly shorter ( P≤0.001 ) . After a follow-up period of 15±4 months , 27 patients in group I ( 49 % ) and 37 patients in group II ( 67 % ) remained free of symptoms of AF and had no AF or atrial flutter during repetitive Holter monitoring without antiarrhythmic drug treatment after a single procedure ( P≤0.05 ) . Conclusions — The rate of success was significantly higher and fluoroscopy times were significantly lower in the group with large isolation areas around both ipsilateral PVs than in those who underwent individual PV isolation Background Atrial fibrillation ( AF ) increases the risk of atrioembolic stroke . However , the role of anticoagulation therapy ( OAT ) in preventing cerebrovascular accidents ( CVA ) after intracardiac echocardiography-guided pulmonary vein antrum isolation ( ICE-PVAI ) is still unclear . In the present study , we evaluated the incidence of CVA following the interruption of OAT 3 months after ICE-PVAI . Methods Between September 2002 and March 2004 , 85 consecutive patients ( 72 men , mean age 62 ± 7 years ) underwent ICE-PVAI for symptomatic drug-refractory AF . Heart disease was present in 61 patients ( 72 % ) ( left ventricular ejection fraction = 58 ± 6 % , LA diameter 44 ± 6 mm ) . Eighty-five consecutive patients who underwent electrical cardioversion ( EC ) for AF , matched for age , sex and heart disease , served as a control group . After 3 months , OAT was stopped unless one of the following conditions was observed : ( i ) AF-recurrence ; ( ii ) severe pulmonary vein stenosis ; ( iii ) non-good atrial contractility on transesophageal echocardiography ; or ( iv ) other indications for OAT . Results In the study group , OAT was stopped after 3 months in 77 patients ( 90 % ) and no CVA occurred during the remaining follow-up ( 15 ± 7 months ) . In the control group , 1 month after EC , OAT was stopped by the referring physician in 29 patients ( 34 % ) . A stroke occurred in five patients ( 6 % ) ( P = 0.09 ; mean P = 0.059 ) during follow-up . In two of these ( 2 % ) , the stroke was fatal . Conclusions Stopping OAT 3 months after ICE-PVAI seems to be safe in patients without AF recurrences after the first 3 months following ablation . Further r and omized-controlled studies are needed to confirm these preliminary data OBJECTIVES To evaluate supplementary cavotricuspid isthmus ( CTI ) ablation as an adjunct to  atrial fibrillation ( AF ) ablation in selected patients . BACKGROUND It is unclear whether routine CTI ablation is beneficial in all patients undergoing AF ablation . METHODS AND RESULTS In patients undergoing AF ablation , additional CTI block was created only for those with typical atrial flutter ( Afl ) before or during the ablation . Out of 188 consecutive patients ( 108 male , 56 + /- 9 years ) , 75 underwent CTI ablation ( Group CTI+ ) and left atrial ( LA ) ablation ( circular mapping-guided extensive pulmonary vein isolation in all and linear LA ablation when required ) , while 113 underwent LA ablation alone ( Group CTI- ) . Group CTI+ patients had smaller LA and less frequently persistent/permanent AF and linear LA ablation . Over a follow-up of 30 + /- 10 months , complications ( 4 % vs 5 % , P = NS ) , typical Afl occurrence ( 1.3 % and 2.6 % , P = NS ) and AF recurrence ( 25 % and 28 % , P = NS ) were similar . Atypical Afl was more common in Group CTI- ( 4 vs 14 % , P = 0.026 ) . Eighty-two percent and 79 % of patients in Groups CTI+ and CTI- , respectively , remained arrhythmia free in stable sinus rhythm without antiarrhythmic drug treatment ( P = NS ) . CONCLUSIONS Avoiding supplementary CTI ablation in AF ablation patients without evidence of typical flutter does not result in a higher incidence of typical Afl . Despite more persistent/permanent AF and larger LA in patients without evidence of typical flutter , a strategy of selective supplementary ablation result ed in similar and low AF recurrence rates in the group without CTI ablation compared with the group with CTI ablation CONTEXT Treatment with antiarrhythmic drugs and anticoagulation is considered first-line therapy in patients with symptomatic atrial fibrillation ( AF ) .  Pulmonary vein isolation ( PVI ) with radiofrequency ablation may cure AF , obviating the need for antiarrhythmic drugs and anticoagulation . OBJECTIVE To determine whether PVI is feasible as first-line therapy for treating patients with symptomatic AF . DESIGN , SETTING , AND PARTICIPANTS A multicenter prospect i ve r and omized study conducted from December 31 , 2001 , to July 1 , 2002 , of 70 patients aged 18 to 75 years who experienced monthly symptomatic AF episodes for at least 3 months and had not been treated with antiarrhythmic drugs . INTERVENTION Patients were r and omized to receive either PVI using radiofrequency ablation ( n=33 ) or antiarrhythmic drug treatment ( n=37 ) , with a 1-year follow-up . MAIN OUTCOME MEASURES Recurrence of AF , hospitalization , and quality of life assessment . RESULTS Two patients in the antiarrhythmic drug treatment group and 1 patient in the PVI group were lost to follow-up . At the end of 1-year follow-up , 22 ( 63 % ) of 35 patients who received antiarrhythmic drugs had at least 1 recurrence of symptomatic AF compared with 4 ( 13 % ) of 32 patients who received PVI ( P<.001 ) . Hospitalization during 1-year follow-up occurred in 19 ( 54 % ) of 35 patients in the antiarrhythmic drug group compared with 3 ( 9 % ) of 32 in the PVI group ( P<.001 ) . In the antiarrhythmic drug group , the mean ( SD ) number of AF episodes decreased from 12 ( 7 ) to 6 ( 4 ) , after initiating therapy ( P = .01 ) . At 6-month follow-up , the improvement in quality of life of patients in the PVI group was significantly better than the improvement in the antiarrhythmic drug group in 5 subclasses of the Short-Form 36 health survey . There were no thromboembolic events in either group . Asymptomatic mild or moderate pulmonary vein stenosis was documented in 2 ( 6 % ) of 32 patients in the PVI group . CONCLUSION Pulmonary vein isolation appears to be a feasible first-line approach for treating patients with symptomatic AF . Larger studies are needed to confirm its safety and efficacy BACKGROUND Left atrial ( LA ) circumferential ablation has been reported to eliminate atrial fibrillation ( AF ) . Whether an ablation without encirclement of the pulmonary veins ( PVs ) is as effective as LA circumferential ablation is not clear . OBJECTIVES The purpose of this study was to compare the efficacy of LA circumferential ablation and nonencircling linear ablation in patients with chronic AF . METHODS Eighty patients with chronic AF were r and omized to undergo LA circumferential ablation ( n = 40 ) or nonencircling linear ablation ( n = 40 ) . In LA circumferential ablation , the PVs were encircled , with additional lines made in the mitral isthmus and posterior wall or roof . In nonencircling linear ablation , 4 + /- 1 ablation lines were created through areas of complex electrograms , with lines in the roof ( 38 ) , anterior wall ( 36 ) , septum ( 40 ) , mitral isthmus ( 32 ) , and posterior annulus ( 6 ) . The endpoint of LA circumferential ablation and nonencircling linear ablation was voltage abatement . RESULTS LA flutter occurred in 15 % after LA circumferential ablation and in 18 % after nonencircling linear ablation ( P = .8 ) . A repeat ablation procedure was performed for recurrent AF in 7 and 11 patients or for atrial flutter in 6 and 4 patients after LA circumferential ablation and nonencircling linear ablation , respectively ( P = .8 ) . At 9 + /- 4 months , the prevalence of AF was 28 % in the LA circumferential ablation and 25 % in the nonencircling linear ablation group ( P = .8 ) . Sixty-eight percent and 60 % of patients were in sinus rhythm and free of AF and atrial flutter in the absence of antiarrhythmic drug therapy after LA circumferential ablation and nonencircling linear ablation , respectively ( P = .5 ) . There were no complications . CONCLUSION Nonencircling linear ablation and LA circumferential ablation are equally efficacious in eliminating chronic AF . However , the advantage of nonencircling linear ablation is that it eliminates the need for ablation along the posterior wall of the LA . Therefore , nonencircling linear ablation may avoid the small but real risk of atrioesophageal fistula formation associated with LA circumferential ablation OBJECTIVES We aim ed to determine the safety and efficacy of pulmonary vein isolation ( PVI ) in atrial fibrillation ( AF ) patients with impaired left ventricular ( LV ) systolic function . BACKGROUND To date , PVI has been performed primarily in patients with normal LV function . Yet , many AF patients have impaired LV systolic function . The outcomes of PVI in patients with impaired LV systolic function are unknown . METHODS We included 377 consecutive patients undergoing PVI between December 2000 and January 2003 . Ninety-four patients had impaired LV function ( ejection fraction [ EF ] < 40 % ) , and they comprised the study group . The control group was the remaining 283 patients who had a normal EF . End points included AF recurrence and changes in EF and quality of life ( QoL ) . RESULTS Mean EF was 36 % in our study group , compared with 54 % in controls . After initial PVI , 73 % of patients with impaired EF and 87 % of patients with normal EF were free of AF recurrence at 14 + /- 6 months ( p = 0.03 ) . In the study group , there was a nonsignificant increase in EF of 4.6 % and significant improvement in QoL. Complication rates were low and included a 1 % risk of pulmonary vein stenosis . CONCLUSIONS Although the AF recurrence rate after initial PVI in impaired EF patients was higher than in normal EF subjects , nearly three-fourths of patients with impaired EF remained AF-free . Although our sample size was nonr and omized , our results suggest PVI may be a feasible therapeutic option in AF patients with impaired EF . R and omized studies with more patients and longer follow-up are warranted BACKGROUND Catheter ablation procedures for treating atrial fibrillation ( AF ) have dramatically increased since triggers of AF were first described in 1998 . OBJECTIVE We explored changes in patient characteristics in patients referred for catheter ablation of AF over a seven-year period from 1999 through 2005 . METHODS Patient characteristics were examined for all patients undergoing AF ablation from 1999 through 2005 at the University of Pennsylvania Health System ( UPHS ) . The gender of patients undergoing ablation was also compared with out patients seen at UPHS with a primary diagnosis of AF . RESULTS From 1999 to 2005 the number of patients undergoing ablation  has increased steadily , from 29 patients in 1999 to 265 patients in 2005 ( P < 0.01 ) . Patients have become older ( 47 to 56 years ; P < 0.01 ) , with more persistent or permanent AF ( 17 % to 45 % ; P < 0.01 ) , larger left atrial size ( 4.0 to 4.4 cm ; P < 0.01 ) , and fewer antiarrhythmic drugs used prior to ablation ( 3.9 to 2.0 drugs ; P < 0.01 ) . Patients undergoing ablation have been predominantly male , with a significantly higher male prevalence than patients seen in the UPHS outpatient primary care clinic with AF ( 77 % vs 59 % male ; P < 0.001 ) . CONCLUSIONS Patients undergoing AF ablation from 1999 to 2005 are older , with larger left atrial size , more persistent/permanent AF , and fewer prior antiarrhythmic agents used . Compared with the gender-specific rates of AF in the population , the majority of patients referred for ablation are men , suggesting a referral bias against this invasive procedure for women . These findings are important for interpreting the outcome of ablation in the current era , and for design ing prospect i ve r and omized trials Background Two important limitations of the data regarding the outcomes of catheter ablation of atrial fibrillation ( AF ) are the short-term follow-up used in most published studies and the lack of single-procedure outcomes . Objective The objective was to report the long-term single-procedure outcomes at our center . Material s and methods The patient population was comprised of 200 consecutive patients who underwent ablation ( 133 men ; age 56 ± 11 years ) . Atrial fibrillation was paroxysmal in 92 ( 46 % ) . Success was defined as absence of symptomatic AF , off antiarrhythmic drug ( AAD ) after a single procedure . Results After a follow-up of 26 ± 11 months , the single-procedure long-term success rate was 28 % with an additional 7 % of patients demonstrating improvement . After including repeat procedures in 64 patients , the overall long-term success rate was 41 % with 11 % demonstrating improvement . Further subgroup analysis of 48 paroxysmal AF patients considered to be optimal c and i date s for the procedure , revealed a long-term success rate of 69 % with an additional 4 % demonstrating improvement . A major complication occurred in 7.9 % of patients . Conclusion The results reveal that the long-term single-procedure success rate  of catheter ablation of AF in a cohort of patients with predominantly non-paroxysmal AF is less than 40 % . The inclusion of redo procedures result ed in an improvement in outcomes . A much higher success rate of 69 % was achieved in patients with paroxysmal AF considered to be optimal c and i date s for this procedure . These results make it clear that further advances in the technique of catheter ablation of AF are needed to improve the safety and efficacy of this procedure . In order to be able to compare outcomes of various techniques in differing patient population s , we urge investigators to report long-term single procedure outcomes Background —Circumferential pulmonary vein ablation ( CPVA ) is effective in curing  atrial fibrillation ( AF ) , but new-onset left atrial tachycardia ( AT ) is a potential complication . We evaluated whether a modified CPVA approach including additional ablation lines on posterior wall and the mitral isthmus would reduce the incidence of AT after PV ablation . Methods and Results —A total of 560 patients ( 291 men , 52 % ; age , 56.5±7.3 years ) entered the study ; 280 were r and omized to CPVA alone ( group 1 ) and 280 to modified CPVA ( group 2 ) . The primary end point was freedom from AT after the procedure . In group 1 , 28 patients ( 10 % ) experienced new-onset AT , and 41 ( 14.3 % ) experienced recurrent AF . In group 2 , 11 patients ( 3.9 % ) experienced AT , and 36 ( 12.9 % ) had recurrent AF . Group 1 was more likely to experience AT than group 2 ( P=0.005 ) . Freedom from AF after ablation was similar in both groups ( P=0.57 ) . Among those in group 1 , gap-related macroreentrant AT was documented in 23 of the 28 patients ( 82 % ) , and focal AT was found in 5 ( 18 % ) . In group 2 , gap-related macroreentrant AT was found in 8 of the 11 patients ( 73 % ) , and focal AT was seen in 3 ( 27 % ) . Two patients in group 1 and 1 patient in group 2 had both AT and AF . The strongest predictor of AT was the presence of gaps ( P<0.001 ) . Conclusions —Modified CPVA is as effective as CPVA in preventing AF but is associated with a lower risk of developing incessant AT Background Various strategies have been used for atrial fibrillation ( AF ) ablation . It is unclear whether adding linear lesions to pulmonary vein ( PV ) isolation has significant advantages . Objectives We assessed the clinical benefit of adding linear lesions in patients undergoing PV isolation for AF . Methods One hundred patients ( 63 male and 37 female ; mean age of 59 ± 11 years ) with documented paroxysmal AF were included in the study . Patients were r and omized into two groups . The first group underwent PV isolation alone . The second group underwent PV isolation and had two linear lesions created ; one line between the superior PVs , and a second line from the left inferior PV to the mitral valve annulus . Patients ’ clinical progress after the ablation was evaluated and compared at 1 , 3 , and 9 months after their respective ablation procedures . Results The linear lesions group maintained sinus rhythm and had fewer symptoms than the lone PV isolation group ( 86 vs. 58 % , respectively ) ( p < 0.05 ) at 1 month . At 9 months , when patients who reverted to AF underwent additional management to regain sinus rhythm ( 90 vs. 82 % , respectively ) ( p = NS ) , there was no statistical difference between the groups regarding the use of antiarrhythmics , the need for electrical cardioversion , and subjective improvement . Conclusion The addition of linear lesions to PV isolation more effectively achieved sinus rhythm initially and fewer patients required additional management to maintain their rhythm when compared to patients who underwent lone PV isolation . However , at 9 months , the overall results were similar in both groups Background — The mainstay of treatment for atrial fibrillation ( AF ) remains pharmacological ; however , catheter ablation has increasingly been used over the last decade . The relative merits of each strategy have not been extensively studied . Methods and Results — We conducted a r and omized multicenter comparison of these 2 treatment strategies in patients with paroxysmal AF resistant to at least 1 antiarrhythmic drug . The primary end point was absence of recurrent AF between months 3 and 12 , absence of recurrent AF after up to 3 ablation procedures , or changes in antiarrhythmic drugs during the first 3 months . Ablation consisted of pulmonary vein isolation in all cases , whereas additional extrapulmonary vein lesions were at the discretion of the physician . Crossover was permitted at 3 months in case of failure . Echocardiographic data , symptom score , exercise capacity , quality of life , and AF burden were evaluated at 3 , 6 , and 12 months by the supervising committee . Of 149 eligible patients , 112 ( 18 women [ 16 % ] ; age , 51.1±11.1 years ) were enrolled and r and omized to ablation ( n=53 ) or “ new ” antiarrhythmic drugs alone or in combination ( n=59 ) . Crossover from the antiarrhythmic drugs and ablation groups occurred in 37 ( 63 % ) and 5 patients ( 9 % ) , respectively ( P=0.0001 ) . At the 1-year follow-up , 13 of 55 patients ( 23 % ) and 46 of 52 patients ( 89 % ) had no recurrence of AF in the antiarrhythmic drug and ablation groups , respectively ( P<0.0001 ) . Symptom score , exercise capacity , and quality of life were significantly higher in the ablation group . Conclusion — This r and omized multicenter study demonstrates the superiority of catheter ablation over antiarrhythmic drugs in patients with AF with regard to maintenance of sinus rhythm and improvement in symptoms , exercise capacity , and quality of life Background —Segmental ostial catheter ablation ( SOCA ) to isolate the pulmonary veins ( PVs ) and left atrial catheter ablation ( LACA ) to encircle the PVs both may eliminate paroxysmal atrial fibrillation ( PAF ) .  The relative efficacy of these 2 techniques has not been directly compared . Methods and Results —Of 80 consecutive patients with symptomatic PAF ( age , 52±10 years ) , 40 patients underwent  PV isolation by SOCA and 40 patients underwent LACA to encircle the PVs . During SOCA , ostial PV potentials recorded with a ring catheter were targeted . LACA was performed by encircling the left- and right-sided PVs 1 to 2 cm from the ostia and was guided by an electroanatomic mapping system ; ablation lines also were created in the mitral isthmus and posterior left atrium . The mean procedure and fluoroscopy times were 156±45 and 50±17 minutes for SOCA and 149±33 and 39±12 minutes for LACA , respectively . At 6 months , 67 % of patients who underwent SOCA and 88 % of patients who underwent LACA  were free of symptomatic PAF when not taking antiarrhythmic drug therapy ( P = 0.02 ) . Among the variables of age , sex , duration and frequency of PAF , ejection fraction , left atrial size , structural heart disease , and the ablation technique , only an increased left atrial size and the SOCA  technique were independent predictors of recurrent PAF . The only complication was left atrial flutter in a patient who underwent LACA . Conclusions —In patients undergoing catheter ablation for PAF  , LACA to encircle the PVs is more effective than SOCA BACKGROUND Stepwise segmental pulmonary vein isolation ( SPVI ) and circumferential pulmonary vein isolation ( CPVI ) have been developed to treat patients with atrial fibrillation ( AF ) , but the preferable approach for paroxysmal AF ( PAF ) has not been established . METHODS AND RESULTS One hundred and ten patients with symptomatic PAF were r and omized into a stepwise SPVI group ( n=55 ) or CPVI group ( n=55 ) . Systemic SPVI combined with left atrial linear ablation tailored by inducibility of AF was performed in the stepwise SPVI group . Circumferential linear ablation around the left and right-sided pulmonary veins ( PVs ) guided by 3-dimensional electroanatomic mapping was performed in the CPVI group . The endpoints of ablation are non-induciblity of AF in the stepwise SPVI group and continuity of circular lesions combined with PV isolation in the CPVI group . After the initial procedures , atrial tachyarrhythmis ( ATa ) recurred within the first 3 months in 23 of the 55 patients ( 41.8 % ) who underwent stepwise SPVI and in 20 of the 55 patients ( 36.4 % ) who had CPVI ( p=0.69 ) . Repeat procedures were performed in 7 patients from the stepwise SPVI group and 5 from the CPVI group ( p=0.76 ) . During the 3 - 9 months after the last procedure , 46 patients ( 83.6 % ) from the CPVI group and 43 ( 78.2 % ) from the stepwise SPVI group did not have symptomatic ATa while not taking anti-arrhythmic drugs ( p=0.63 ) . Severe subcutaneous hematoma or PV stenosis occurred in 3 patients . CONCLUSIONS The efficacy of stepwise SPVI is comparable to that of CPVI for patients with PAF BACKGROUND Current atrial fibrillation ( AF ) ablation involves isolation of all pulmonary veins ( PVs ) with or without additional linear lesions . However , whether such extensive ablation is necessary is unclear . OBJECTIVE The purpose of this study was to assess the efficacy of different ablation strategies on long-term AF control . METHODS We prospect ively r and omized patients to undergo isolation of all versus arrhythmogenic PVs ( identified by st and ardized stimulation protocol ) .  PV isolation was guided by circular mapping catheter . The endpoint was entry/exit block persisting for > or = 20 minutes . Patients were evaluated at three clinic visits ( at 6 weeks , 6 months , and 1 year ) and multiple transtelephonic monitoring periods . Antiarrhythmic drugs were discontinued at 6 weeks . Primary study endpoint was long-term AF control ( freedom or > 90 % reduction in AF burden off or on previously ineffective antiarrhythmic drugs at 1 year after a single ablation procedure ) . RESULTS Over a 20-month period , 105 patients ( 76 men and 29 women , age 57 + /- 9 years ; paroxysmal AF = 77 ) were r and omized , and 103 patients completed 1-year follow-up ( 51 patients in all-PV arm , 52 patients in arrhythmogenic PV arm ) . The primary endpoint was achieved in 75 ( 73 % ) patients and was similar in patients r and omized to all-PV arm versus arrhythmogenic PV arm [ 38 ( 75 % ) patients vs 37 ( 71 % ) patients , respectively ; odds ratio 1.18 , 95 % confidence interval 0.50 , 2.83 , P = .70 ] . Secondary study endpoints , including freedom from AF off antiarrhythmic drugs , total procedure/fluoroscopy times , and occurrence of serious adverse events , were not different between the two groups . CONCLUSION In a r and omized comparison , isolation of arrhythmogenic veins was as efficacious as empiric isolation of all veins in achieving long-term AF control AIMS Segmental pulmonary vein ( PV ) isolation by radiofrequency ( RF ) catheter ablation has become a curative therapy for atrial fibrillation ( AF ) . However , the long procedure time limits the wide application of this procedure . The aim of the current study was to compare a novel ablation technique with a high power output and short application time vs. a conventional technique using a low power output and long application time . METHODS AND RESULTS The study included 90 consecutive patients ( age 53+/-10 years ; 66 men ) . Segmental PV isolation was performed by irrigated RF catheter ablation in both groups . In the conventional group ( Group 1 , 45 patients ) , the power output was limited to 30 W with a target temperature of 50 degrees C and an RF preset duration of 120 s. In the novel group ( Group 2 , 45 patients ) , the maximum power output was preset to 45 W , with a target temperature of 55 degrees C and duration of 20 s. In Group 2 , a significant reduction in the PV isolation time ( 127+/-57 vs. 94+/-33 min , P<0.02 ) , mean fluoroscopy time ( 73+/-23 vs. 55+/-16 min , P<0.001 ) , and radiation dose was observed . According to the application time and number , Group 2 showed a reduction in RF application time , but a higher number of RF applications were required for creation of complete PV isolation . During a mean follow-up of 15+/-7 months , a total of 74 % of patients in Group 1 and 76 % of patients in Group 2 demonstrated stable SR . CONCLUSION Segmental PV isolation using a high power output and short application time is safe and effective in PV isolation in patients with AF . This technique can significantly reduce the procedure and fluoroscopy time compared with a low-power output technique Background —The AFFIRM Study showed that treatment of patients with atrial fibrillation and a high risk for stroke or death with a rhythm-control strategy offered no survival advantage over a rate-control strategy in an intention-to-treat analysis . This article reports an “ on-treatment ” analysis of the relationship of survival to cardiac rhythm and treatment as they changed over time . Methods and Results —Modeling techniques were used to determine the relationships among survival , baseline clinical variables , and time-dependent variables . The following baseline variables were significantly associated with an increased risk of death : increasing age , coronary artery disease , congestive heart failure , diabetes , stroke or transient ischemic attack , smoking , left ventricular dysfunction , and mitral regurgitation . Among the time-dependent variables , the presence of sinus rhythm ( SR ) was associated with a lower risk of death , as was warfarin use . Antiarrhythmic drugs ( AADs ) were associated with increased mortality only after adjustment for the presence of SR . Consistent with the original intention-to-treat analysis , AADs were no longer associated with mortality when SR was removed from the model . Conclusions —Warfarin use improves survival . SR is either an important determinant of survival or a marker for other factors associated with survival that were not recorded , determined , or included in the survival model . Currently available AADs are not associated with improved survival , which suggests that any beneficial antiarrhythmic effects of AADs are offset by their adverse effects . If an effective method for maintaining SR with fewer adverse effects were available , it might be beneficial BACKGROUND Catheter ablation has become the first line of therapy in patients with symptomatic recurrent , drug-refractory atrial fibrillation ( AF ) . The occurrence of an atrioesophageal fistula is a rare but serious complication after AF-ablation procedures . This risk is even present during segmental pulmonary vein ( PV ) ablation procedures because the esophagus does frequently have a very close anatomical relationship to the right or left PV ostia . The aim of the present study was to analyze whether the exclusion of areas adjacent to the esophagus does have a significant effect on the success rates after segmental pulmonary vein ablation procedures . METHODS Forty-three consecutive patients with symptomatic paroxysmal AF were enrolled in this study . In all patients , a segmental PV ablation procedure was performed . The procedures were facilitated by a 3D real-time visualization of the circumferential mapping catheter placed in the pulmonary veins using the NavX system ( St. Jude Medical , St. Paul , MN , USA ; open irrigated tip ablation catheter ; 43 degrees C ; 30 W ) . In 21 patients , a complete ostial PV isolation was attempted regardless of the anatomical relationship between the ablation sites and the esophagus ( group A ) . In the remaining 22 patients , the esophagus was marked by a stomach tube and areas adjacent to the esophagus were excluded from the ablation procedure ( group B ) . After discharge , patients were scheduled for repeated visits at the arrhythmia clinic at 1 , 3 , and 6 months after the ablation procedure . RESULTS The segmental pulmonary vein ablation procedure could be performed as planned in all patients . In group A , all pulmonary veins could be isolated successfully in 14 out of 21 patients ( 67 % ) . A mean number of 3.7 pulmonary veins ( SD + /- 0.5 PVs ) were isolated per patient . The main reasons for an incomplete PV isolation were : small diameter of the PVs , side branches close to the ostium , or poorly accessible PV ostia . In group B , all PVs could be isolated successfully in only 12 out of 22 patients ( 55 % ; P = 0.54 ) . A mean number of 3.2 PVs ( SD + /- 0.9 PVs ) were isolated per patient ( P = 0.05 ) . This was mostly due to a close anatomical relationship to the esophagus . The ablation strategy had to be modified in 16/22 patients in group B because of a close anatomical relationship between the left ( n = 10 ) or right ( n = 6 ) PV ostia and the esophagus . After 3 months , the percentage of patients free from an AF recurrence was not significantly different between the two groups ( 90 % vs 95 % ; P = 0.61 ) . After 6 months , there was no significant difference between the success rates either ( 81 % vs 82 % ; P = 1.0 ) . There were no major complications in both groups . CONCLUSIONS The exclusion of areas adjacent to the esophagus results in a moderately higher percentage of incompletely isolated PVs . However , it does not have a significant effect on the AF recurrence rate during short-term and mid-term follow-up AIMS Women have an increased risk for atrial fibrillation (AF)-related complications and there is evidence towards a reduced efficacy of the rhythm control strategy than men . A catheter-based strategy is therefore widely attractive , but the impact of gender on catheter ablation ( CA ) of AF remains undefined . METHODS AND RESULTS We included 221 consecutive patients ( 150 men ) who underwent CA of drug-refractory AF .  Gender differences in clinical presentation and outcomes were compared . Women were older ( P = 0.002 ) , had a longer history of AF ( P = 0.04 ) , and were more likely to have hypertension ( P = 0.04 ) . Moreover , a concomitant valvular heart disease tended to be more common in women ( 32.4 vs. 23.3 % ; P = 0.28 ) and left atrium dimensions were significantly larger ( P = 0.003 ) . However , acute success rate and complications rate were similar between genders . After 22.5 + /- 11.8 months of follow-up , the overall freedom from arrhythmia recurrences was similar ( 83.1 vs. 82.7 % in men ) , and a similar improvement in SF-36 quality of life scores was achieved in both groups . CONCLUSION Women are referred for AF ablation later with a more complex clinical pre-operative presentation . Despite this higher risk profile in women , no differences were detected in clinical outcomes . Our findings indicate that CA of AF appears to be safe and effective in women as in men AIMS A detailed appreciation of the left atrial/pulmonary venous ( LA/PV ) anatomy may be important in improving the safety and success of catheter ablation for AF . The aim of this r and omized study was to determine the impact of computed tomographic ( CT ) integration into an electroanatomic mapping ( EAM ) system on clinical outcome in patients undergoing catheter ablation for atrial fibrillation ( AF ) . METHODS AND RESULTS Eighty patients with AF were r and omized to undergo first-time wide encirclement of ipsilateral PV pairs using EAM alone ( 40 patients ) or with CT ( 40 patients , Cartomerge ) . Wide encirclement of the pulmonary veins was performed using irrigated radiofrequency ablation with the electrophysiological endpoint of electrical isolation ( EI ) . The primary endpoint was single-procedure success at 6 month follow up . Acute and long-term procedural outcomes were also determined . There was no significant difference in single procedure success between EAM ( 56 % ) and cavotricuspid isthmus image ( CTI ) ( 50 % ) groups ( P = 0.9 ) . Acute procedural outcomes ( EI , PV reconnection , sinus rhythm restored by ablation in persistent AF ) , fluoroscopy , and procedure duration s ( EI of right PVs , EI of left PVs , total ) did not differ significantly between EAM and CTI groups . CONCLUSION Image integration to guide catheter ablation for AF did not significantly improve the clinical outcome . Achieving PV EI is the critical determinant of procedural success rather than the mapping tools used to achieve it BACKGROUND We conducted a r and omized , controlled trial of circumferential pulmonary-vein ablation for the treatment of chronic atrial fibrillation . METHODS A total of 146 patients with a mean ( + /-SD ) age of 57+/-9 years who had chronic atrial fibrillation were r and omly assigned to receive amiodarone and undergo two cardioversions during the first three months alone ( the control group ) or in combination with circumferential pulmonary-vein ablation . Cardiac rhythm was assessed with daily telephonic transmissions for one year . The left atrial diameter and the severity of symptoms were assessed at 12 months . RESULTS Among the 77 patients assigned to undergo circumferential pulmonary-vein ablation , ablation was repeated because of recurrent atrial fibrillation in 26 percent of patients and atypical atrial flutter in 6 percent . An intention-to-treat analysis showed that 74 percent of patients in the ablation group and 58 percent of those in the control group were free of recurrent atrial fibrillation or flutter without antiarrhythmic-drug therapy at one year ( P=0.05 ) . Among the 69 patients in the control group , 53 ( 77 percent ) crossed over to undergo circumferential pulmonary-vein ablation for recurrent atrial fibrillation by one year and only 3 ( 4 percent ) were in sinus rhythm without antiarrhythmic-drug therapy or ablation . There were significant decreases in the left atrial diameter ( 12+/-11 percent , P<0.001 ) and the symptom severity score ( 59+/-21 percent , P<0.001 ) among patients who remained in sinus rhythm after circumferential pulmonary-vein ablation . Except for atypical atrial flutter , there were no complications attributable to circumferential pulmonary-vein ablation . CONCLUSIONS Sinus rhythm can be maintained long term in the majority of patients with chronic atrial fibrillation by means of circumferential pulmonary-vein ablation independently of the effects of antiarrhythmic-drug therapy , cardioversion , or both . The maintenance of sinus rhythm is associated with a significant decrease in both the severity of symptoms and the left atrial diameter Background —An anatomic approach of left atrial radiofrequency circumferential ablation ( LACA ) to encircle the pulmonary veins is often effective in eliminating  paroxysmal atrial fibrillation ( AF ) .  However , no electrophysiological end points other than voltage abatement and /or conduction slowing or block across ablation lines have been used . It has been unclear whether noninducibility of AF is a clinical ly useful end point . Methods and Results —In 100 patients with paroxysmal AF ( mean age , 55±10 years ) , LACA to encircle the left- and right-sided pulmonary veins was performed during AF , with additional ablation lines in the posterior left atrium and mitral isthmus , with an 8-mm-tip catheter . After completion of this lesion set , sinus rhythm was present , and AF lasting > 60 seconds was not inducible in 40 patients ( 40 % ; group 1 ) . The 60 patients in whom AF was still present or who still had inducible AF were r and omly assigned to no further ablation ( group 2 ; 30 patients ) or to additional ablation lines along the left atrial septum , roof , and /or anterior wall where there were fractionated electrograms ( group 3 ; 30 patients ) . In group 3 , AF was rendered noninducible in 27 of 30 patients ( 90 % ) . At a 6-month follow-up , 67 % of patients in group 2 were free of AF without drug therapy compared with 86 % of patients in group 3 . ( P=0.05 , log-rank test ) . Left atrial flutter occurred in 17 % and 27 % of patients in each group , respectively ( P=0.3 ) . Conclusions —After LACA in patients with paroxysmal AF , AF usually can be rendered noninducible by additional ablation at sites of fractionated electrograms . Noninducibility of AF attained by additional electrogram-guided left atrial ablation may be associated with a better midterm clinical outcome than when AF is still inducible after LACA alone Background — Data on the comparative value of the circumferential pulmonary vein and the segmental pulmonary vein ablation for interventional treatment of atrial fibrillation are limited . We hypothesized that the circumferential pulmonary vein ablation approach was superior to the segmental pulmonary vein ablation approach . Methods and Results —One hundred patients with highly symptomatic atrial fibrillation were r and omly assigned to undergo either circumferential ( n=50 ) or segmental pulmonary vein ablation ( n=50 ) . Freedom from atrial tachyarrhythmias in a 7-day Holter monitoring at 6 months was the primary end point . Secondary end points were freedom of arrhythmia-related symptoms and a composite of pericardial tamponade , thromboembolic complications , and pulmonary vein stenosis ( safety end point ) . On the basis of the results of the 7-day Holter monitoring at 6 months , 21 patients ( 42 % ) after circumferential pulmonary vein ablation and 33 patients ( 66 % ) after segmental pulmonary vein ablation ( P=0.02 ) were free of atrial tachyarrhythmia episodes . During the 6-month follow-up period , 27 patients ( 54 % ) after circumferential pulmonary vein ablation and 41 patients ( 82 % ) after segmental pulmonary vein ablation remained free of arrhythmia-related symptoms ( P<0.01 ) . No significant difference was found in the safety end point ( 6 versus 7 events ; P=0.77 ) in the circumferential versus segmental pulmonary vein ablation group , respectively . Conclusions —This study demonstrates no superiority of the circumferential pulmonary vein ablation over segmental pulmonary vein ablation for treatment of atrial fibrillation in terms of efficacy and safety Background —The objective of this study was to assess the impact of intracardiac echocardiography ( ICE ) on the long-term success and complications in patients undergoing pulmonary vein isolation ( PVI ) for treatment of atrial fibrillation ( AF ) . Methods and Results —Three hundred fifteen patients underwent PVI for treatment of AF . Each patient underwent ostial isolation of all PVs using a cooled-tip ablation catheter . PVI was performed using circular mapping ( CM ) alone ( group 1 , 56 patients ) , CM and ICE ( group 2 , 107 patients ) , and CM and ICE with titration of radiofrequency energy based on visualization of microbubbles by ICE ( group 3 , 152 patients ) . After a mean follow-up time of 417±145 days , 19.6 % ( 11 of 56 ) , 16.8 % ( 18 of 107 ) , and 9.8 % ( 15 of 152 ) of patients in groups 1 , 2 , and 3 experienced recurrence of AF , respectively . Moreover , whereas no group 3 patient experienced severe ( > 70 % ) PV stenosis , severe PV stenosis was documented in 3 ( 3.5 % ) of 56 patients in group 1 and in 2 ( 1.8 % ) of 107 patients in group 2 ( P < 0.05 ) . No embolic events were detected in group 3 patients . Conclusions —Intracardiac echocardiography improves the outcome of cooled-tip PVI . Power adjustment guided by direct visualization of microbubble formation reduces the risk of PV stenosis and improves long-term cure INTRODUCTION Dormant pulmonary vein ( PV ) conduction can be provoked by adenosine triphosphate ( ATP ) after extensive encircling pulmonary vein isolation ( EEPVI ) . However , the clinical implication of reconnection between the left atrium ( LA ) and isolated PVs provoked by ATP ( ATP-reconnection ) remains unknown . METHODS AND RESULTS We studied the clinical consequences of ATP-reconnection during intravenous isoproterenol infusion ( ISP-infusion ) . EEPVI severs conduction between the LA and ipsilateral PVs at their junction . Radiofrequency energy is applied at a distance from the PV ostia guided by double Lasso catheters placed within the ipsilateral superior and inferior PVs . This study comprised 82 patients ( 67 men , 56 + /- 9 years old ) with atrial fibrillation ( AF ) who underwent injection of ATP during ISP infusion after successful EEPVI ( ATP(+ ) group ) . We compared clinical characteristics of 170 patients who underwent earlier EEPVI prior to our use of ATP injection after successful EEPVI ( ATP(N/D ) group ) with those of ATP(+ ) group patients who underwent one session of EEPVI .  ATP-reconnection occurred in 34 ( 41 % ) of 82 ATP(+ ) group patients . Additional radiofrequency applications were performed to eliminate ATP-reconnection in all ipsilateral PVs . Continuous ATP-reconnection of more than 20 seconds duration occurred in six ( 7.3 % ) of 82 patients . A total of 102 ( 60 % ) of 170 patients in the ATP(N/D ) group had no recurrence of AF , whereas 60 ( 73 % ) of 82 ATP(+ ) group patients who underwent only one EEPVI session have had no recurrence of AF in a 6.1 + /- 3.3-month follow-up period ( P = 0.04 ) . CONCLUSION Radiofrequency application for provoked ATP-reconnection may reduce clinical AF recurrence INTRODUCTION This study examines the feasibility of atrial fibrillation ( AF ) ablation using registered three-dimensional computed tomography ( CT ) images of the left atrium with fluoroscopy . METHODS AND RESULTS A total of 50 consecutive patients with symptomatic AF refractory to medical therapy ( 32 paroxysmal , 18 persistent , age 55 + /- 10 years ) were r and omized to undergo a catheter-based AF ablation procedure with or without the CT-fluoroscopy guidance system . All patients underwent preprocedural contrast-enhanced CT imaging and segmentation of the left atrium . For the CT-fluoroscopy group , circumferential lesions encompassing the pulmonary vein ( PV ) antrum and linear lesions along the roof of the left atrium between the superior PVs and the mitral isthmus were created on the CT image , which was registered with real-time fluoroscopy . The registered images were then used to navigate the ablation catheters to the sites of planned ablation . After the ablation sites were completed , any remaining PV potentials were isolated with electrophysiological guidance . In the control patients , the same technique was performed without using the CT-fluoro guidance system . CT scans were accurately registered to fluoroscopic images with minimal manual correction . Operators could navigate catheters on the registered images to preplanned , extraostial sites for ablation . CT-fluoroscopy guidance decreased procedure duration and fluoro times ( P < 0.05 ) . At a mean follow-up of 9 + /- 2 months , 21 patients ( 84 % ) in the CT-fluoro guidance group and 16 patients ( 64 % ) in the control group have had no recurrence of AF . CONCLUSION CT-fluoroscopic-guided left atrial ablation is feasible and allows appropriate catheter manipulation in the left atrium BACKGROUND The deployment of an ablation line connecting the left inferior PV to the mitral annulus ( mitral isthmus line [ MIL ] ) enhances the efficacy of pulmonary vein disconnection ( PVD ) in preventing atrial fibrillation ( AF ) recurrences . OBJECTIVES To investigate the long-term effect of the additional linear lesion in a prospect i ve r and omized study . METHODS One hundred and eighty-seven patients ( 37 females , mean age : 55 + /- 11 years ) with paroxysmal ( 126 ) or persistent ( 61 patients ) AF , were prospect ively r and omized into two groups : PVD ( group A , 92 patients ) or PVD combined with MIL ( group B , 95 patients ) , performed by means of an irrigated-tip ablation catheter . RESULTS Successful disconnection of all PVs was achieved in all patients . A bidirectional block ( BB ) along the left atrial isthmus was obtained in 72 of 95 ( 76 % ) patients in group B , most of whom required additional RF pulses from within the distal CS . A transient ischemic attack occurred in 1 patient of group A , and a cardiac tamponade occurred in 1 patient of group B. At 1 year , 53 + /- 5 % ( group A ) and 71 + /- 5 % ( group B ) remained arrhythmia free ( P = 0.01 ) ; subgroup analysis highlights a higher improvement among patients with persistent AF ( 74 + /- 9 % vs 36 + /- 9 % ; P < 0.01 ) than what was observed in paroxysmal AF ( 76 + /- 6 % vs 62 + /- 6 % ; P < 0.05 ) ; antiarrhythmic drugs were continued in 56 % and 50 % , respectively , in groups A and B ( P = ns ) . CONCLUSIONS The addition of mitral isthmus line to the PV disconnection allows a significant improvement of sinus rhythm maintenance rate , particularly in patients with persistent AF , without the risk for major complications BACKGROUND The limited efficacy and complications of segmental ostial pulmonary vein isolation ( PVI ) for treating atrial fibrillation ( AF ) have been discussed so , in the present study the feasibility and efficiency of performing segmental pulmonary vein ( PV ) antrum isolation to treat AF were assessed . METHODS AND RESULTS A total of 187 patients with drug-refractory AF ( paroxysmal 120 , persistent 67 ) underwent segmental PVI guided by circumferential 20-electrode catheters ( Lasso ) . Radiofrequency ( RF ) current was delivered either at the ostium using a regular Lasso ( 15 - 20 mm in diameter , 70 patients : Group 1 ) or at the antrum using a larger Lasso ( 25 - 30 mm in diameter , 117 patients : Group 2 ) . A significantly wider region had to be ablated , with a longer RF application time , to isolate all 4 PVs in Group 2 patients than in Group 1 patients . Although the rate of recurrence of AF after the initial session was equal in both groups , a significantly greater number of patients were free from AF after a mean of 1.4 procedures in Group 2 than in Group 1 ( 93 % vs 76 % for paroxysmal AF , 78 % vs 48 % for persistent AF ) . CONCLUSIONS Segmental antral PVI using large-sized Lasso catheters was found to be more effective and safer than ostial PVI for the treatment of AF AIMS The study was intended to assess the prognostic value of inducibility of atrial fibrillation ( AF ) after radio frequency ablation . METHODS AND RESULTS Two hundred and thirty four patients with drug-resistant paroxysmal ( n=165 ) or persistent AF ( n=69 ) underwent either Lasso-guided segmental pulmonary vein isolation ( n=83 ) or CARTO-guided left atrial circumferential ablation ( n=151 ) . After ablation , two attempts to induce AF ( > 1 min ) by decremental coronary sinus stimulation were performed . Patients were followed for at least 6 months ( median : 12.7 months ) . At 6 months of follow-up , 67 % of patients with paroxysmal and 48 % of patients with persistent AF were AF-free . Inducibility of AF was a significant predictor of AF recurrence in univariate [ hazard ratio (HR)=2.32 , P<0.001 ] and multivariable ( HR=2.19 , P<0.001 ) Cox regression analyses . The prognostic value of inducibility was present in both patients with paroxysmal ( HR=2.38 , P=0.001 ) and persistent AF ( HR=1.91 , P=0.034 ) and did not significantly differ between both ablation techniques . The sensitivity , specificity , positive , and negative predictive values of the AF induction test to predict the 6-month ablation outcome were 46.7 , 75 , 53.8 , and 69.2 % , respectively . CONCLUSION Inducibility of AF after ablation is a significant predictor of recurrent AF . However , owing to the low diagnostic accuracy of the AF induction test , non-inducibility does not qualify as reliable procedural endpoint BACKGROUND Catheter ablation ( CA ) by wide encirclement of pulmonary veins ( WEPV ) restores sinus rhythm in up to 95 % . Complex PV-left atrial ( LA ) connections make achieving electrical isolation ( EI ) challenging . We examined anatomical and technical features associated with resistance to EI during WEPV in a prospect i ve study . METHODS One hundred one consecutive patients with symptomatic AF underwent first-time CA guided by electroanatomic mapping and CT integration ( Cartomerg ) . Following double-transseptal access , WEPV was performed . After completion of PV encirclement , the line was mapped and where no signal could be obtained , CA was performed inside the WE line at the site of earliest PV breakthrough on the circular mapping catheter . Sites of EI were tagged . Anatomic studies of corresponding regions of the venoatrial junction in 24 adult hearts were performed . RESULTS Sites resistant to EI were located at the inferior quadrant ( P < 0.001 ) for the RSPV , superior quadrant ( P < 0.001 ) for the RIPV , and the inferior and anterior quadrants ( P < 0.001 ) for the LSPV . EI was significantly less frequent at the posterior quadrant ( P < 0.001 ) for the LIPV . To achieve EI , CA was necessary inside the WE on the intervenous ridge on the right in 51 % and on the left in 41 % . The LPV/LAA ridge was investigated by anatomic studies that demonstrated considerable variation in the narrowest width ( 3 - 23.7 mm ) and transmural thickness ( 1 - 5 mm ) . CONCLUSION Sites of EI after WEPV have a preferential distribution determined by anatomic features . CA on the intervenous ridge is required in a significant proportion of patients to achieve EI . Atrial folds and ridges increase myocardial thickness creating technical and anatomic challenges for achieving transmural lesions AIMS We conducted a multi-centre , prospect i ve , controlled , r and omized trial to investigate the adjunctive role of ablation therapy to antiarrhythmic drug therapy in preventing  atrial fibrillation ( AF )  relapses in patients with paroxysmal or persistent AF in whom antiarrhythmic drug therapy had already failed . METHODS AND RESULTS One hundred and thirty seven patients were r and omized to ablation and antiarrhythmic drug therapy ( ablation group ) or antiarrhythmic drug therapy alone ( control group ) . In the ablation group , patients underwent cavo-tricuspid and left inferior pulmonary vein (PV)-mitral isthmus ablation plus circumferential PV ablation . The primary end-point of the study was the absence of any recurrence of atrial arrhythmia lasting > 30 s in the 1-year follow-up period , after 1-month blanking period . Three ( 4.4 % ) major complications were related to ablation : one patient had a stroke during left atrium ablation , another suffered transient phrenic paralysis , and the third had a pericardial effusion which required pericardiocentesis . After 12 months of follow-up , 63/69 ( 91.3 % ) control group patients had at least one AF recurrence , whereas 30/68 ( 44.1 % ) ( P<0.001 ) ablation group patients had atrial arrhythmia recurrence ( four patients had atrial flutter , 26 patients AF ) . CONCLUSION Ablation therapy combined with antiarrhythmic drug therapy is superior to antiarrhythmic drug therapy alone in preventing atrial arrhythmia recurrences in patients with paroxysmal or persistent AF in whom antiarrhythmic drug therapy has already failed OBJECTIVES This study was design ed to investigate the potential of circumferential pulmonary vein ( PV ) ablation for atrial fibrillation ( AF ) to maintain sinus rhythm ( SR ) over time , thus reducing mortality and morbidity while enhancing quality of life ( QoL ) . BACKGROUND Circumferential PV ablation is safe and effective , but the long-term outcomes and its impact on QoL have not been assessed or compared with those for medical therapy . METHODS We examined the clinical course of 1,171 consecutive patients with symptomatic AF who were referred to us between January 1998 and March 2001 . The 589 ablated patients were compared with the 582 who received antiarrhythmic medications for SR control . The QoL of 109 ablated and 102 medically treated patients was measured with the SF-36 survey . RESULTS Median follow-up was 900 days ( range 161 to 1,508 days ) . Kaplan-Meier analysis showed observed survival for ablated patients was longer than among patients treated medically ( p < 0.001 ) , and not different from that expected for healthy persons of the same gender and calendar year of birth ( p = 0.55 ) . Cox proportional-hazards model revealed in the ablation group hazard ratios of 0.46 ( 95 % confidence interval [ CI ] , 0.31 to 0.68 ; p < 0.001 ) for all-cause mortality , of 0.45 ( 95 % CI , 0.31 to 0.64 ; p < 0.001 ) for morbidities mainly due to heart failure and ischemic cerebrovascular events , and of 0.30 ( 95 % CI , 0.24 to 0.37 ; p < 0.001 ) for AF recurrence . Ablated patients ' QoL , different from patients treated medically , reached normative levels at six months and remained unchanged at one year . CONCLUSIONS Pulmonary vein ablation improves mortality , morbidity , and QoL as compared with medical therapy . Our findings pave the way for r and omized trials to prospect a wider application of ablation therapy for AF AIMS The aim of the study was to investigate the feasibility of performing segmental pulmonary vein ( PV ) isolation guided by the NavX ( Endocardial Solutions , St Jude Medical , Inc. , St Paul , MN , USA ) system without the three-dimensional ( 3D ) geometric reconstruction option and whether the use of NavX system will reduce the radiation exposure and procedure duration . METHODS AND RESULTS The study included 64 patients with symptomatic paroxysmal or permanent atrial fibrillation , in whom PV isolation was performed using fluoroscopic guidance ( n=32 ) or the NavX system ( n=32 ) . Pulmonary vein mapping with a circular mapping catheter allowed the identification and localization of myocardial connections between the PV and the left atrium . PV isolation was performed by radiofrequency ablation of these connections at the atrial aspect of the PV ostium . Primary success rate for isolated PVs did not differ significantly in patients ablated under fluoroscopic guidance vs. those ablated under guidance of NavX system [ 100/107 PVs ( 93.5 % ) vs. 120/124 PV ( 96.8 % ; P = n.s . ) ] . Compared with fluoroscopy guided procedures , NavX-guided procedures showed a significant reduction in the fluoroscopy time ( 75.8+/-24.5 vs. 38.9+/-19.3 min , P<0.05 ) , total X-ray exposure ( 93.2+/-51.6 vs. 56.6+/-37.9 Gy cm(2 ) , P=0.03 ) , and total procedural time ( 237.7+/-65.4 vs. 188.6+/-62.7 min , P=0.01 ) . The mean follow-up was 9.5+/-3.0 months . One patient in each group was lost to follow-up . Seven-day Holter monitoring showed that 23 of 31 patients ( 74.2 % ) in the NavX-guided group and 21 of 31 patients ( 67.7 % ) in the fluoroscopy-guided group were in sinus rhythm ( P=0.57 ) . CONCLUSION The 3D visualization of the catheters by NavX system allows a rapid and precise visualization of the mapping and ablation catheters at the PV ostia and markedly reduces fluoroscopy time , total X-ray exposure , and procedural duration during PV isolation compared with ablation performed under fluoroscopy guidance Abstract Background : Catheter ablation of atrial fibrillation is a rapidly evolving art . There is currently no consensus as to optimal methodology . We report a sequential experience , during which three distinct ablation techniques were utilized . Methods : A cohort of 112 patients in whom atrial fibrillation onset was precipitated by ectopy arising solely from myocardium investing the pulmonary veins underwent catheter ablation using one of three techniques : focal ( Group A ) ; individual vein encircling ( Group B ) ; vestibule encircling ( Group C ) . In each group , non-fluoroscopic guidance of the mapping and ablation process was provided by the t and em use of CARTORM and intracardiac echocardiography . Results : In all groups , endocardial topography was complex , and ablation electrode-endocardial contact was often unstable . Maximal electrode temperatures were low , despite frequent echocardiographic evidence of myocardial boiling . A significant progression in the number of radiofrequency energy applications between groups A and C was observed . Although acute suppression of atrial fibrillation inducibility was observed uniformly , chronic suppression rates were significantly different : Group A = 47 % ; Group B ; 69 % ; Group C = 87 % . Conclusions : In this non-concurrent cohort , the rate of chronic suppression of atrial fibrillation correlated with the amount of myocardium ablated or electrically isolated . Prospect i ve data will be required to further evaluate whether “ more is better . BACKGROUND Cerebrovascular events are an important complication during pulmonary vein antrum isolation ( PVAI ) .  Microembolic signals ( MES ) have been associated with stroke and neurological impairment . However , the incidence of MES during PVAI , and their relationship to microbubble formation and radiofrequency ( RF ) parameters are unknown . OBJECTIVES We sought to assess the relationship between MES , microbubble detection , and neurological outcome and the impact of RF titration strategy on these parameters . METHODS We studied 202 patients in two groups undergoing PVAI using an intracardiac echocardiography (ICE)-guided technique .  MES were detected by transcranial Doppler ( TCD ) using insonation of the middle cerebral arteries . The number of microbubbles on ICE were qualitatively labeled as FEW , MODERATE , and SHOWER . In group I ( n = 107 ) , RF output was titrated to avoid microbubble formation and in group II ( n = 95 ) , st and ard power-limited RF output was used . RESULTS TCD detected MES in all 202 patients during PVAI with an average of 1,793 + /- 547 per patient ; 90 % were detected during left atrial ablation . Over 85 % of MES occurred after microbubbles . Group I patients had significantly lower numbers of MES ( 1,015 + /- 438 per patient ) compared to group II patients ( 2,250 + /- 864 per patient ) ( P < 0.05 ) . Group II also had a 3.1 % incidence of acute neurological complications versus 0.9 % in group I ( P = 0.10 ) . Patients with clinical events had significantly higher numbers of MES . There were no significant correlations between RF power , temperature , or impedence and MES number . CONCLUSIONS MES directly correlate to the amount of microbubble formation on ICE , and may result in cerebroembolic complications . Titration of RF according to microbubble formation by ICE during PVAI may be important for minimizing the occurrence of MES and possibly acute neurological complications INTRODUCTION Congestive heart failure ( CHF ) and atrial fibrillation ( AF ) are frequently linked , and when associated produce additive deleterious effects . In this prospect i ve study , the effects of catheter ablation for AF  in patients with impaired left ventricular ( LV ) function are presented . METHODS Baseline data and clinical outcome have been prospect ively collected in 105 consecutive patients who underwent pulmonary vein ablation for the control of AF .  We evaluated 40 patients affected by LV dysfunction with ejection fraction (EF)<40 % and compared them to the remaining 65 patients with normal ventricular function in terms of changes in LV function , maintenance of sinus rhythm , and quality of life during follow-up . RESULTS After a mean follow-up of 14+/-2 months , 87 % of patients with impaired LV function and 92 % of patients with normal ventricular function were in sinus rhythm , with or without antiarrhythmic therapy ( P = NS ) . A significant improvement in LVEF and fractional shortening was documented in patients with CHF ( 33+/-2 % vs 47+/-3 % , and 19+/-4 % vs 30+/-3 % , P<0.01 for both comparisons ) . Evaluation of exercise capacity and quality of life documented better improvements in patients with CHF compared to patients without CHF . CONCLUSIONS Catheter ablation in patients with LV dysfunction is feasible , not associated with higher procedural complications , and provides a significant improvement in LV performance , symptoms , and quality of life during follow-up BACKGROUND Radiofrequency catheter ablation ( RFCA ) for curing atrial fibrillation ( AF ) is often followed by early recurrence and delayed cure , so the present study investigate the predictive factors this in patients with chronic AF . METHODS AND RESULTS Ninety-two consecutive patients ( 70 males ; mean age , 58.7+/-6.4 years ) with chronic AF who underwent RFCA for treatment of symptomatic AF were enrolled .  Early recurrence of AF ( ERAF ) occurred in 45 patients after ablation . Not achieving AF termination could predict ERAF ( odds ratio ( OR ) 0.95 ; 95 % confidence interval ( CI ) 0.84 - 1.13 ; p=0.02 ) in multivariate analysis . During a follow-up of 12+/-11 ( range , 5 - 25 ) months , delayed cure occurred in 35.6 % ( 16/45 ) of the patients with ERAF . Left atrial size and AF termination during ablation were related to delayed cure . AF termination was the only independent predictive factor for delayed cure ( OR 1.47 ; 95 % CI 1.05 - 1.87 ; p=0.02 ) . CONCLUSION Not achieving AF termination is the only independent predictor of ERAF . Among patients with ERAF , those with a smaller left atrium and AF termination have a higher probability of delayed cure . AF termination can independently predict delayed cure . These results emphasize the importance of AF termination during ablation for patients with chronic AF INTRODUCTION We performed a prospect i ve study to compare efficacy and safety of both open irrigation tip ( OIT ) technology with intracardiac echo (ICE)-guided energy delivery in patients presenting for PVAI . METHODS AND RESULTS Fifty-three patients presenting for PVAI were r and omized to ablation using an OIT catheter ( Group 1 , 26 patients ; temperature and power were set at 50 degrees and 50 W , respectively , with a saline pump flow rate of 30 mL/min ) or radiofrequency ( RF ) energy delivery under ICE guidance ( Group 2 , 27 patients ; energy was titrated based on microbubbles formation ) . The mean procedure time and fluoroscopy exposure were lower in Group 1 ( 164 + /- 42 min and 7,560 + /- 2,298 microGray m2 vs 204 + /- 47 min and 12,240 + /- 4,356 microGray m2 ; P = 0.005 and 0.008 , respectively ) . Moreover , the duration s of RF lesions applied per PV antrum was lower in Group 1 compared with Group 2 ( 5.1 + /- 2.2 min vs 9.2 + /- 3.2 min , P = 0.03 , respectively ) . Within 24 hours after PVAI in 35.7 % ( all erythema ) of Group 1 and 57.1 % ( 21.4 % erythema and 35.7 % necrosis ) of Group 2 , patients ' esophageal wall changes were documented . After 14 + /- 2 months of follow up , recurrences were documented in 19.2 % of Group 1 and 22.2 % of Group 2 patients . CONCLUSION Although both OIT and ICE-guided energy delivery possess a similar effect in treating AF , OIT seems to be superior in terms of achieving isolation and shortening fluoroscopy exposure . Moreover , a lower incidence of esophageal wall injury was observed utilizing OIT for PVAI OBJECTIVES The aim of this study was to compare -- in patients with persistent and permanent atrial fibrillation (AF)--the  efficacy and safety of left atrial ablation with that of a biatrial approach . BACKGROUND Left atrium-based catheter ablation of AF , although very effective in the paroxysmal form of the arrhythmia , has an insufficient efficacy in patients with persistent and permanent AF . METHODS Eighty highly symptomatic patients ( age , 58.6 + /- 8.9 years ) with persistent ( n = 43 ) and permanent AF ( n = 37 ) , refractory to antiarrhythmic drugs , were r and omized to two different ablation approaches guided by electroanatomical mapping . A procedure including circumferential pulmonary vein , mitral isthmus , and cavotricuspid isthmus ablation was performed in 41 cases ( left atrial ablation group ) . In the remaining 39 patients ( biatrial ablation group ) , the aforementioned approach was integrated by the following lesions in the right atrium : intercaval posterior line , intercaval septal line , and electrical disconnection of the superior vena cava . RESULTS During follow-up ( mean duration 14 + /- 5 months ) , AF recurred in 39 % of patients in the left atrial ablation group and in 15 % of patients in the biatrial ablation group ( p = 0.022 ) . Multivariable Cox regression analysis showed that ablation technique was an independent predictor of AF recurrence during follow-up . CONCLUSIONS In patients with persistent and permanent AF , circumferential pulmonary vein ablation , combined with linear lesions in the right atrium , is feasible , safe , and has a significantly higher success rate than left atrial and cavotricuspid ablation alone OBJECTIVES We compared ablation strategy with antiarrhythmic drug therapy ( ADT ) in patients with paroxysmal atrial fibrillation ( PAF ) . BACKGROUND Atrial fibrillation ( AF ) ablation strategy is superior to ADT in patients with an initial history of PAF , but its role in patients with a long history of AF as compared with ADT remains a challenge . METHODS One hundred ninety-eight patients ( age , 56 + /- 10 years ) with PAF of 6 + /- 5 years ' duration ( mean AF episodes 3.4/month ) who had failed ADT were r and omized to AF ablation by circumferential pulmonary vein ablation ( CPVA ) or to the maximum tolerable doses of another ADT , which included flecainide , sotalol , and amiodarone . Crossover to CPVA was allowed after 3 months of ADT . RESULTS By Kaplan-Meier analysis , 86 % of patients in the CPVA group and 22 % of those in the ADT group who did not require a second ADT were free from recurrent atrial tachyarrhythmias ( AT ) ( p < 0.001 ) ; a repeat ablation was performed in 9 % of patients in the CPVA group for recurrent AF ( 6 % ) or atrial tachycardia ( 3 % ) . At 1 year , 93 % and 35 % of the CPVA and ADT groups , respectively , were AT-free . Ejection fraction , hypertension , and age independently predicted AF recurrences in the ADT group . Circumferential pulmonary vein ablation was associated with fewer cardiovascular hospitalizations ( p < 0.01 ) . One transient ischemic attack and 1 pericardial effusion occurred in the CPVA group ; side effects of ADT were observed in 23 patients . CONCLUSIONS Circumferential pulmonary vein ablation is more successful than ADT for prevention of PAF with few complications . Atrial fibrillation ablation warrants consideration in selected patients in whom ADT had already failed and maintenance of sinus rhythm is desired . ( A Controlled R and omized Trial of CPVA Versus Antiarrhythmic Drug Therapy in for Paroxysmal AF : APAF/01 ; http:// clinical trials.gov/ct/show ; NCT00340314 ) INTRODUCTION The aim of this study was to compare the outcome of anatomical pulmonary vein ( PV ) radiofrequency ( RF ) ablation with that of an integrated approach ( anatomical with electrophysiological confirmation of PV disconnection ) . METHODS Sixty consecutive patients affected by drug-refractory paroxysmal ( 39 ) , persistent ( 13 ) , and permanent ( 8) atrial fibrillation ( AF ) were assigned to an anatomical ( group A : 30 patients ; 25 male , 5 female , mean age : 55 + /- 7 years ) or integrated approach ( group B : 30 patients ; 26 male , 4 female , mean age : 52 + /- 9 years ) . In all cases , RF ablation was performed by means of the Carto system in order to anatomically create circumferential lines around PVs . In group B , the persistence of PV potentials was then assessed with a multipolar circular catheter . If PV potentials persisted , RF pulses targeting the electrophysiological breakthroughs were delivered to disconnect PVs . RESULTS Total procedure duration , fluoroscopy time , and RF delivery time were similar in both groups : 227 + /- 43 , 50 + /- 23 , and 43 + /- 16 minutes ( group A ) ; 232 + /- 32 , 55 + /- 15 , and 42 + /- 10 minutes ( group B ) , respectively ( ns ) . One asymptomatic PV stenosis and one pericardial effusion occurred in group A and B , respectively . After 15.4 + /- 7.4 months , 17 ( 57 % ) group A patients and 25 ( 83 % ) group B patients were in stable sinus rhythm ( P = 0.02 ) ( RR 1.78 ; 95 % CI : 1.7 - 2.9 ) . CONCLUSIONS PV ablation by means of an integrated anatomical and electrophysiological approach seems more effective than a purely anatomical RF ablation approach . Electrophysiological confirmation of PV disconnection could be a useful marker of successful RF treatment of AF BACKGROUND Noninducibility of  sustained atrial fibrillation ( AF ) after pulmonary vein isolation ( PVI )  has been shown to be associated with a better clinical outcome . We evaluated the role of clinical variables that could predict noninducibility of sustained AF after PVI . METHODS AND RESULTS Data were collected prospect ively from 181 patients ( 153 male ; age 54 + /- 9 years ) referred for ablation of drug-refractory symptomatic paroxysmal AF ( duration < or = 7 days ) . Clinical variables were evaluated with regard to their ability of predicting noninducibility of sustained AF  ( < or = 10 minutes ) after PVI . Univariate analysis was performed on all collected variables followed by multivariate analysis for variables showing a P value < 0.1 . After PVI , sustained AF was noninducible in 97 ( 54 % ) patients . The following clinical variables showed a significant difference between the groups : body weight , longest AF episode , duration of AF history , presence or absence of structural heart disease , left ventricular ( LV ) hypertrophy , prior cardioversion , left atrial ( LA ) parasternal , and longitudinal diameters and LV diameters . On multivariate analysis , three independent predictors of noninducibility were identified : a shorter duration of AF episodes ( AF < 12 hours : RR 0.01 ( 0.002 - 0.06 ) , P < 0.001 ; AF 12 - 48 hours : RR 0.07 ( 0.01 - 0.37 ) , P = 0.001 ) ; LA longitudinal diameter < 57 mm ( RR 0.33 ( 0.13 - 0.82 ) , P = 0.016 ) ; and absence of LV hypertrophy ( RR 0.15 ( 0.04 - 0.63 ) , P = 0.01 ) . CONCLUSIONS Shorter AF episodes , smaller LA longitudinal diameter , and absence of LV hypertrophy are independent predictors of noninducibility of sustained AF after PVI BACKGROUND Data on the procedural safety of pulmonary vein radiofrequency catheter ablation for atrial fibrillation ( AF ) are as yet scant . OBJECTIVE The aims of the present study were to prospect ively evaluate the incidence of early complications of pulmonary vein ablation for AF in an unselected population of consecutive patients , and to identify possible predictors . METHODS From April 2005 to October 2006 , data from 1,011 consecutive patients who were undergoing radiofrequency catheter ablation for every type of AF in 10 Italian centers were collected . All complications occurring from the admission of the patient up to the 30th day were considered . RESULTS No procedure-related death was observed . Complications occurred in 40 patients ( 3.9 % ) : 12 ( 1.2 % ) had peripheral vascular complications , 8 ( 0.8 % ) had conservatively treated pericardial effusion , 6 ( 0.6 % ) had cardiac tamponade ( successfully drained ) , 5 ( 0.5 % ) had cerebral embolisms , 4 ( 0.4 % ) presented pulmonary vein stenosis > 50 % , and 5 ( 0.5 % ) presented other isolated adverse events . History of coronary artery disease ( odds ratio 5,603 , 95 % confidence interval 1,559 to 20,139 , P < .008 ) characterized patients who presented with hemorrhagic complications . CONCLUSION Early complications of pulmonary vein catheter ablation seem to be fewer than in the early years of AF ablation , but still occur in 3.9 % of procedures INTRODUCTION Circumferential pulmonary vein ablation ( CPVA ) with the endpoint of pulmonary vein ( PV ) isolation has been developed as an effective therapy for atrial fibrillation ( AF ) . This endpoint can be achieved either by closing gaps along circular lines or by segmental PV isolation inside the circular lines after creation of initial CPVA lesions . We investigated whether the clinical outcome depends on the PV isolation approach used during the first-time CPVA procedure . METHODS AND RESULTS One hundred consecutive patients ( 69 male ; age , 56.7 + /- 11.6 years ) who underwent first-time CPVA for treatment of symptomatic AF were enrolled . PV isolation was r and omly achieved either by CPVA alone ( aggressive CPVA [ A-CPVA ] group , n = 50 ) or by a combination of CPVA with segmental PV ostia ablation ( modified CPVA [ M-CPVA ] group , n = 50 ) . Recurrence of atrial tachyarrhythmias ( ATa ) within 3 months after the initial procedure occurred in 30 patients ( 60 % ) in the M-CPVA group and in only 15 patients ( 30 % ) in the A-CPVA group ( P < 0.01 ) . ATa relapse after the first 3 months was detected in 21 patients ( 42 % ) in the M-CPVA group , compared with 9 patients ( 18 % ) in the A-CPVA group ( P = 0.01 ) . At 13 + /- 4 months , patients treated by the A-CPVA approach had greater freedom from ATa recurrence than patients who underwent M-CPVA ( P = 0.01 ) . The M-CPVA approach was the only independent predictor associated with procedural failure ( RR 0.318 ; 95 % CI 0.123 - 0.821 ; P = 0.02 ) . CONCLUSIONS When PV isolation is the endpoint of CPVA , the efficacy of the A-CPVA approach is better than that of M-CPVA BACKGROUND A detailed appreciation of left atrial/pulmonary vein ( LA/PV ) anatomy may be important in improving the safety and success of catheter ablation ( CA ) for atrial fibrillation ( AF ) . OBJECTIVES The aim of this nonr and omized study was to determine the impact of computerized tomography ( CT ) image integration into a 3-dimensional ( 3D ) mapping system on the clinical outcome of patients undergoing CA for AF . METHODS Ninety-four patients ( age : 56 + /- 10 years ) with AF ( paroxysmal 46 , persistent 48 ) underwent wide encirclement of ipsilateral PV pairs using irrigated radiofrequency ablation with the endpoint of electrical isolation . Ablation was guided by 3D mapping alone ( electroanatomic 24 , noncontact 23 ) in 47 ( 3DM group ) patients and by CT image integration ( Cartomerge ) in 47 ( CT group ) . In persistent AF , a combination of linear ablation and targeted ablation of complex fractionated electrograms was also performed . RESULTS Successful PV electrical isolation did not differ between the two groups . A significant reduction in fluoroscopy times was demonstrated in the CT group ( 49 + /- 27 minutes vs 3DM group 62 + /- 26 minutes , P = 0.03 ) . Arrhythmia recurrence was reduced in the CT group ( 32 % vs 51 % in the 3DM group , P < 0.01 ) . In 30 symptomatic patients ( 12 CT and 18 3DM ) , repeat procedures for AF ( 13 in 3DM and 5 CT , P < or = 0.10 ) and AT ( 5 in 3DM and 7 CT , P = NS ) were performed . Overall success on 7-day monitor off antiarrhythmic drugs was achieved in 60 % in the 3DM group when compared with 83 % in the CT group ( P < 0.05 ) at a follow-up of 25 + /- 5 weeks . CONCLUSION CA for AF guided by CT integration was associated with reduced fluoroscopy times , arrhythmia recurrence , and increased restoration of sinus rhythm . Improved visualization of complex LA geometries might improve the safety and success of CA for AF Background — Obesity is a risk factor for atrial fibrillation and other cardiovascular conditions . Our objective was to determine whether catheter-based ablation effectively treated atrial fibrillation in obese patients . Methods and Results — Five hundred twenty-three consecutive patients with symptomatic , medication-refractory atrial fibrillation underwent catheter ablation .  Patients were grouped by body mass index ( lean , < 25 kg/m2 ; overweight , 25 to 29.9 kg/m2 ; obese , ≥30 kg/m2 ) . Outcome and quality of life were measured with a general health survey ( Medical Outcomes Study 36-item Short-Form General Health Survey [ SF-36 ] ) ; patients were assessed before ablation and at 3 and 12 months after the procedure . Two hundred twenty-eight study patients ( 44 % ) were overweight , and 201 ( 38 % ) were obese . Twelve months after curative ablation , 72 % of patients were free of atrial fibrillation without the use of antiarrhythmic agents ; 84 % were arrhythmia free when those receiving medication were included . Atrial fibrillation was eliminated in 75 % , 72 % , and 70 % of the lean , overweight , and obese patients , respectively , at 12 months ( P=0.41 , trend test ) . SF-36 scores were lower for patients with higher body mass index ( P<0.05 ) at baseline . SF-36 scores improved in every functional domain for all body mass index groups after ablation . The mean SF-36 total physical score increased from 59±20 at baseline to 77±19 in 12 months ( P<0.001 ) . The total mental health score improved from 66±18 to 79±16 in 12 months ( P<0.001 ) . Conclusions — Catheter ablation of atrial fibrillation was effective in obese patients . Coexistence of atrial fibrillation and obesity indicated lower SF-36 scores , but the improvement in quality of life was consistent across all body mass index categories OBJECTIVES The use of antiarrhythmic drugs after ablation is a controversial issue when evaluating the efficacy of atrial fibrillation ( AF ) ablation . This study compares in a prospect i ve and r and omized fashion the impact of an antiarrhythmic drug in preventing AF recurrence after AF ablation . METHODS From February 2004 to May 2005 , 107 consecutive patients ( mean age 57 + /- 10 years , 69 men ) , with paroxysmal ( 60 % ) or persistent ( 40 % ) drug refractory AF , were r and omly assigned to ablation alone ( Group A , 53 patients ) or combined with the best antiarrhythmic therapy , preferably amiodarone ( Group B , 54 patients ) . All patients underwent cavo-tricuspid and left inferior pulmonary vein (PV)-mitral isthmus ablation plus circumferential PV ablation , using a guided electro-anatomical approach . St and ard electrocardiograms ( ECG ) , and ambulatory and transtelephonic ECG monitoring  were used to assess AF recurrences . Recurrences during the first month after ablation were excluded from this analysis . RESULTS At 12 months of follow-up , no significant difference was observed in the rates of AF recurrences between Group A ( 18/53 patients , 34 % ) and Group B ( 16/54 patients , 30 % ) . The percentage of patients with > /= 1 asymptomatic AF episode was higher in Group B than in Group A ( 10/16 patients , 63 % , vs 5/18 patients , 28 % , P = 0.04 ) . CONCLUSIONS Continuing antiarrhythmic drug therapy in patients who undergo catheter ablation for AF did not lower the rate of AF recurrences . Antiarrhythmic drugs increased the proportion of patients with asymptomatic AF episodes AIMS Catheter ablation of atrial fibrillation ( AF ) is centred on pulmonary vein ( PV ) ablation with or without additional atrial substrate modification . These procedures may be prolonged with significant fluoroscopy exposure . This study evaluates a new non-fluoroscopic navigation system during ablation of AF . METHODS AND RESULTS Seventy-two patients undergoing catheter ablation of symptomatic drug refractory AF were prospect ively r and omized to ablation with ( n=35 ; study group ) or without ( n=37 ; control group ) non-fluoroscopic navigation . PV isolation was performed in all patients . In patients with persistent or inducible sustained AF after PV isolation linear ablation was performed by joining the superior PVs . PV isolation was achieved in all patients ; fluoroscopy ( 15.4+/-3.4 vs. 21.3+/-6.4 min ; P<0.001 ) and procedural ( 52+/-12 vs. 61+/-17 min ; P=0.02 ) duration s were significantly reduced in the study group . Linear block was achieved in 37 of the 39 patients ; with a significant reduction in fluoroscopy ( 5.6+/-2.2 vs. 9.9+/-4.8 min ; P=0.003 ) and procedural ( 14.7+/-5.5 vs. 26.6+/-16.9 min ; P=0.007 ) duration s in the study group . After a follow-up of 6.9+/-2.9 months ( range 3 - 10 ) , 26 ( 74 % ) patients in the non-fluoroscopic navigation group and 29 ( 78 % ) patients in the control group were arrhythmia-free after the first procedure . CONCLUSION This prospect ively r and omized study demonstrates significant reduction of fluoroscopy exposure and procedural duration using supplementary non-fluoroscopic imaging system for AF ablation OBJECTIVE To compare safety and efficacy of 8-mm versus cooled tip catheter in achieving electrical isolation ( EI ) of pulmonary veins ( PV ) for long-term control of  atrial fibrillation ( AF ) .  BACKGROUND There is paucity of studies comparing safety/efficacy of 8-mm and cooled tip catheters in patients undergoing AF ablation . METHODS AND RESULTS This was a r and omized and patient-blinded study . Subjects were followed by clinic visits ( at 6 weeks and 6 months ) and transtelephonic monitoring ( 3-week duration ) done around each visit . Primary endpoints were : ( 1 ) long-term AF control ( complete freedom and /or > 90 % reduction in AF burden on or off antiarrhythmic drugs at 6 months after a single ablation ) , and ( 2 ) occurrence of serious adverse events ( cardiac tamponade , stroke , LA-esophageal fistula , and /or death ) .  Eighty-two patients ( age 56 + /- 9 years , 60 males , paroxysmal AF = 59 ) were r and omized ( 42 patients to 8-mm tip and 40 patients to cooled tip ) . EI of PVs was achieved in shorter time by the 8-mm tip as compared with cooled tip catheter ( 40 + /- 23 minutes vs 50 + /- 30 minutes ; P < 0.05 ) but long-term AF control was not different between the two ( 32 patients [ 78 % ] vs 28 patients [ 70 % ] , respectively ; P = NS ) . One serious adverse event occurred in each group ( LA-esophageal fistula and stroke , respectively ) and no significant PV stenosis was observed in either . CONCLUSION EI of PVs using either 8-mm or cooled tip catheter results in long-term AF control in the majority after a single ablation procedure , with comparable efficacy and safety AIMS In many laboratories , cooled-tip catheters have replaced 8 mm-tip catheters due to their theoretical advantage of achieving larger lesions and avoiding charring . However , direct comparisons between the catheters in the subset of atrial fibrillation ( AF ) ablation are scarce . The aim of this study was to compare the efficacy , safety , and lesion extension created by 8 mm-tip vs. cooled-tip catheter with different energy setting s for circumferential pulmonary vein ablation ( CPVA ) . METHODS AND RESULTS A series of 221 consecutive patients with symptomatic AF were included in the study . Circumferential pulmonary vein ablation was performed using an 8 mm-tip catheter ( 55 W , 50 degrees C ) in 90 patients ( Group 1 ) , a cooled-tip ( 30 W , 45 degrees C ) in 42 ( Group 2 ) , and a cooled-tip ( 40 W , 45 degrees C ) in 89 ( Group 3 ) . In a subgroup of 60 patients , troponin I ( TpnI ) , creatinine kinase , and myoglobin values were obtained before and at 12 and 24 h after ablation . At 1 year follow-up , the probability of being arrhythmia-free after a single procedure was 53 , 35 , and 55 % in patients from Groups 1 , 2 , and 3 , respectively . Ablation with a cooled-tip catheter at 30 W led to a higher recurrence rate ( P = 0.030 ) and was identified in Cox regression analysis as an independent predictor of AF recurrence ( HR , 1.713 ; 95 % CI , 1.02 - 2.90 ; P = 0.045 ) . There were no differences in intra-procedure complications ( 2.2 vs. 5.6 vs. 4.9 % , P = 0.542 ) . The myocardial lesion according to TpnI was smaller in Group 2 ( P = 0.02 ) . CONCLUSION The cooled-tip catheter at 30 W was less efficacious than both the 8 mm catheter and the cooled-tip with a 40 W power setting BACKGROUND We question ed whether the empirical four pulmonary vein ( PV ) isolation ( EmPVI ) was necessary in patients with paroxysmal atrial fibrillation ( PAF ) triggered from clearly and reproducibly defined arrhythmogenic PVs . METHODS We compared the selective or ipsilateral isolation of the PVs triggering AF ( SePVI : n = 42 ) and EmPVI ( n = 35 ) in 77 patients ( males 80.5 % , mean age 53.0 + /- 13.4 years ) with PAF who underwent radiofrequency catheter ablation ( RFCA ) .  Arrhythmogenic PVs were identified by the immediate recurrence of AF three consecutive times after cardioverting AF . RESULTS ( 1 ) The duration of the RF energy deliveries ( P < 0.01 ) and total procedure time ( P < 0.01 ) were shorter for the SePVI than the EmPVI . ( 2 ) During a mean follow-up of 38.6 + /- 23.1 months , the AF recurrence rate was 38.1 % in the SePVI group and 25.7 % in the EmPVI group ( P = NS ) . ( 3 ) A redo-ablation was performed in 25 patients , and 81.0 % of the recurrent arrhythmogenic foci were found at a previously ablated PV or ipsilateral PV . ( 4 ) In 15.4 % of the SePVI and 20.0 % of the EmPVI procedures , AF recurred after 32.5 + /- 15.2 months of the redo-ablation . Subsequently , the AF-free rate for each group was 88.1 % ( 37/42 ) in the SePVI group and 91.4 % ( 32/35 ) in the EmPVI group ( P = NS ) . CONCLUSIONS In patients with clearly documented arrhythmogenic PVs , the SePVI of the PV triggering the AF or an ipsilateral PV had a comparable long-term success rate and shorter RF energy delivery and procedure times than the EmPVI BACKGROUND Congestive heart failure and atrial fibrillation often coexist , and each adversely affects the other with respect to management and prognosis . We prospect ively evaluated the effect of catheter ablation for atrial fibrillation on left ventricular function in patients with heart failure . METHODS We studied 58 consecutive patients with congestive heart failure and a left ventricular ejection fraction of less than 45 percent who were undergoing catheter ablation for atrial fibrillation .  We selected as controls 58 patients without congestive heart failure who were undergoing ablation for atrial fibrillation , matched according to age , sex , and classification of atrial fibrillation . We evaluated the patients ' left ventricular function and dimensions , symptom score , exercise capacity , and quality of life at baseline and at months 1 , 3 , 6 , and 12 . RESULTS After a mean ( + /-SD ) of 12+/-7 months , 78 percent of the patients with congestive heart failure and 84 percent of the controls remained in sinus rhythm ( P=0.34 ) ( 69 percent and 71 percent , respectively , were in sinus rhythm without the administration of antiarrhythmic drugs ) . The patients with congestive heart failure had significant improvement in left ventricular function ( increases in the ejection fraction and fractional shortening of 21+/-13 percent and 11+/-7 percent , respectively ; P<0.001 for both comparisons ) , left ventricular dimensions ( decreases in the diastolic and systolic diameters of 6+/-6 mm and 8+/-7 mm , respectively ; P=0.03 and P<0.001 , respectively ) , exercise capacity , symptoms , and quality of life . The ejection fraction improved significantly not only in patients without concurrent structural heart disease ( 24+/-10 percent , P<0.001 ) and those with inadequate rate control before ablation ( 23+/-10 percent , P<0.001 ) , but also in those with coexisting heart disease ( 16+/-14 percent , P<0.001 ) and adequate rate control before ablation ( 17+/-15 percent , P<0.001 ) . CONCLUSIONS Restoration and maintenance of sinus rhythm by catheter ablation without the use of drugs in patients with congestive heart failure and atrial fibrillation significantly improve cardiac function , symptoms , exercise capacity , and quality of life BACKGROUND There are two approaches to the treatment of atrial fibrillation : one is cardioversion and treatment with antiarrhythmic drugs to maintain sinus rhythm , and the other is the use of rate-controlling drugs , allowing atrial fibrillation to persist . In both approaches , the use of anticoagulant drugs is recommended . METHODS We conducted a r and omized , multicenter comparison of these two treatment strategies in patients with atrial fibrillation and a high risk of stroke or death . The primary end point was overall mortality . RESULTS A total of 4060 patients ( mean [ + /-SD ] age , 69.7+/-9.0 years ) were enrolled in the study ; 70.8 percent had a history of hypertension , and 38.2 percent had coronary artery disease . Of the 3311 patients with echocardiograms , the left atrium was enlarged in 64.7 percent and left ventricular function was depressed in 26.0 percent . There were 356 deaths among the patients assigned to rhythm-control therapy and 310 deaths among those assigned to rate-control therapy ( mortality at five years , 23.8 percent and 21.3 percent , respectively ; hazard ratio , 1.15 [ 95 percent confidence interval , 0.99 to 1.34 ] ; P=0.08 ) . More patients in the rhythm-control group than in the rate-control group were hospitalized , and there were more adverse drug effects in the rhythm-control group as well . In both groups , the majority of strokes occurred after warfarin had been stopped or when the international normalized ratio was subtherapeutic . CONCLUSIONS Management of atrial fibrillation with the rhythm-control strategy offers no survival advantage over the rate-control strategy , and there are potential advantages , such as a lower risk of adverse drug effects , with the rate-control strategy . Anticoagulation should be continued in this group of high-risk patients UNLABELLED PV isolation at the antrum ( PVAI ) has improved safety and efficacy of ablation procedures for atrial fibrillation ( AF ) . AF triggers from the superior vena cava ( SVC ) may compromise the outcome of PVAI . PURPOSE We evaluated the ( 1 ) incidence of SVC triggers , ( 2 ) feasibility of empiric SVC electrical isolation ( SVCI )  as an adjunct to PVAI , and ( 3 ) SVCI safety . METHODS AND RESULTS Of 190 patients ( group I ) , 24 ( 12 % ) showed SVC triggers . Following PVAI , seven patients had AT originating from the SVC and three had AF . After SVCI , all 24 patients were  arrhythmia-free  450 + /- 180 days post procedure . In the subsequent 217 patients ( group II ) , empirical SVCI was performed following PVAI . Sixty-six of all 407 patients ( 16 % ) experienced recurrence of AF . A repeat procedure in 25 of the 66 patients showed that five ( 20 % ) had AF recurrence initiated by SVC triggers , of whom four were among group I patients ( 4/190 ; 2 % ) and one was from group II ( 1/217 ; 0.4 % ) , ( P < 0.05 ) . Transient diaphragmatic paralysis can be avoided by pacing at the lateral aspect of the SVC using high output ( 30 mA ) . There was no SVC stenosis on CT scans before or 3 months after the procedure . There was no sinus node injury . CONCLUSIONS The SVC harbors the majority of non-PV triggers of AF . SVCI is feasible , safe , and may be considered as an adjunctive strategy to PVAI for ablation of AF . The long-term favorable outcome of this hybrid approach remains to be evaluated in a larger series of patients AIMS Circumferential pulmonary vein isolation ( CPVI ) is an established strategy for atrial fibrillation ( AF ) ablation . Superior vena cava ( SVC ) , by harbouring the majority of non-pulmonary vein ( PV ) foci , is the most common non-PV origin for AF . However , it is unknown whether CPVI combined with SVC isolation ( SVCI ) could improve clinical results and whether SVCI is technically safe and feasible . METHODS AND RESULTS A total of 106 cases ( 58 males , average age 66.0 + /- 8.8 years ) with paroxysmal AF were included for ablation . They were allocated r and omly to two groups : CPVI group ( n = 54 ) and CPVI + SVCI group ( n = 52 ) . All cases underwent the procedure successfully . Pulmonary vein isolation was achieved in all cases . The procedural time and fluoroscopic time were comparable between the two groups . The mean ablation time for SVC was 7.8 + /- 2.7 min . Superior vena cava isolation was obtained in 50/52 cases . In the remaining two cases , SVCI was not achieved because of obviating diaphragmatic nerve injury . During a mean follow-up of 4 + /- 2 months , 12 ( 22.2 % ) cases in the CPVI group and 10 ( 19.2 % ) cases in the CPVI + SVCI group had atrial tachyarrhythmias ( ATa ) recurrence ( P = 0.70 ) . Nine of 12 cases in the CPVI group and 8/10 cases in the CPVI + SVCI group underwent reablation ( P = 0.86 ) , and PV reconnection occurred in 7/9 cases in the CPVI group and in 8/8 cases in the CPVI + SVCI group . All PV reconnection was reisolated by gaps ablation . There was no SVC reconnection in the CPVI + SVCI group . In two cases without PV reconnection from the CPVI group , SVC-originated short run of atrial tachycardia was identified and eliminated by the SVCI . At the end of 12 months of follow-up , 50 cases ( 92.6 % ) in the CPVI group and 49 ( 94.2 % ) in the CPVI + SVC group were free of ATa recurrence ( P = 0.73 ) . CONCLUSION In our series of paroxysmal AF patients , empirically adding SVCI to CPVI did not significantly reduce the AF recurrence after ablation . Superior vena cava isolation may be useful , however , in selected patients in whom the SVC is identified as a trigger for AF . However , because of the preliminary property of the study and its relatively small sample size , the impact of SVCI on clinical results should be evaluated in a large series of patients Different techniques have been proposed to treat atrial fibrillation ( AF ) by catheter ablation . This study compares a new three-dimensional ( 3D ) nonfluoroscopic navigation system with conventional fluoroscopy to guide pulmonary vein ( PV ) isolation . A total of 60 consecutive patients with paroxysmal or persistent AF were r and omly assigned to 3D-guided ablation ( group 1 , n = 30 ) , versus conventional fluoroscopy guidance ablation ( group 2 , n = 30 ) . Complete PV isolation was achieved in both groups . The mean duration of fluoroscopy exposure ( 22 + /- 8 vs 56 + /- 10 minutes ) , and radiofrequency delivery ( 5 + /- 1 vs 10 + /- 3 minutes ) were significantly shorter in group 1 than in group 2 , P < 0.05 for both comparisons ) . The mean procedural time in group 1 was longer ( 225 + /- 15 minutes ) than in group 2 ( 156 + /- 10 minutes , P < 0.05 ) due to the learning curve and time spent to generate the 3D maps . Over a mean follow-up of 7 + /- 2 months , 6 patients ( 20 % ) in group 2 had AF recurrences compared to 3 patients ( 10 % ) in group 1 ( ns ) . The new nonfluoroscopic 3D system allows a high-resolution reconstruction of the left atrium and PVs . It significantly reduces the mean radiofrequency delivery and fluoroscopy times as opposed to ablation performed under fluoroscopy guidance AIMS To compare clinical characteristics , procedure complexity , acute and long-term outcome of ' ablate and pace ' ( A&P ) with pulmonary vein isolation ( PVI ) in patients with drug-refractory atrial fibrillation ( AF ) . So far , only few small studies have compared the two procedures . METHODS AND RESULTS We analysed retrospectively a cohort of symptomatic consecutive patients with drug-refractory AF . Group 1 included 100 patients treated with A&P and Group 2 included 144 patients treated with PVI .  Group 1 patients were older ( 74 + /- 8 vs. 56 + /- 9 years ; P < 0.0001 ) , had lower left ventricular ejection fraction ( 50 + /- 13 % vs. 59 + /- 7 % ; P < 0.05 ) , and a lower prevalence of paroxysmal AF ( 46 % vs. 65 % ; P < 0.05 ) . Acute success was not statistically different ( 98 % vs. 92.3 % , P = ns ) . Group 1 patients had shorter procedure time and lower radiation exposure with respect to Group 2 patients ( 70 + /- 15 vs. 204 + /- 58 min , and 8 + /- 4 vs. 57 + /- 22 min ; P < 0.0001 , respectively ) . After a median follow-up of 29 months ( I , III quartile ; 15 , 40 months ) vs. 25 months ( I , III quartile ; 8 , 36 months ) ( P = ns ) , all the patients in Group 1 were free of symptomatic AF , while 113 patients ( 79 % ) of Group 2 were in stable sinus rhythm ( P < 0.0001 ) . Persistent or permanent AF has been documented in 58 patients ( 58 % ) of Group 1 vs. 11 ( 8 % ) of Group 2 ( P < 0.0001 ) . CONCLUSION In this series ( i ) patients treated with A&P and PVI for drug-refractory AF showed significant differences in clinical profile ; ( ii ) A&P is a shorter and less complex procedure , but is associated with a higher rate of persistent AF ; ( iii ) symptomatic recurrences of paroxysmal AF were more frequent in PVI group . R and omized studies appear necessary to identify the best strategy in selected cases BACKGROUND Both segmental ostial and circumferential extraostial pulmonary vein ( PV ) isolation have been proven effective in the treatment of atrial fibrillation ( AF ) . However , the recurrence of AF and PV conduction after the 2 ablation strategies has never been compared in a r and omized study . METHODS A total of 100 consecutive patients ( age 56 + /- 10 ; 71 men ) with symptomatic AF ( paroxysmal , 51 ; persistent , 49 ) were r and omized to segmental ostial ( n = 54 ) or circumferential extraostial ( n = 46 ) PV isolation . A circular catheter positioned at the ostium of each target PV guided the ostial PV isolation . Extraostial PV isolation was performed by encircling the paired left and right PVs , respectively , guided by an electroanatomic mapping system . RESULTS A total of 84 % of the patients had recurrent AF after the first PV isolation procedure , showing 72 % with AF and 12 % with organized left atrial tachycardia . In patients undergoing reablation , all but 2 patients had recurrence of left atrium PV conduction ( > 95 % ) . During a mean follow-up of 12 months without antiarrhythmic medication , 57 % of patients who underwent extraostial PV isolation were free of arrhythmia symptoms compared with 31 % of patients who underwent ostial PV isolation ( P < .05 ) . This difference in success rate between the 2 ablation strategies was mainly seen in patients known with persistent AF ( 52 % and 15 % , respectively ; P = .02 ) as opposed to patients with paroxysmal AF ( 65 % and 46 % , respectively ; P = .26 ) . CONCLUSIONS Overall , the more proximal , extraostial PV isolation was found to be superior to ostial PV isolation , especially in patients known with persistent AF . A high recurrence rate of 84 % after a single complete PV isolation procedure was seen . At reablation , more than 95 % had recurrence of left atrium PV conduction regardless of the procedure used , supporting the idea that complete PV isolation seems essential to prevent arrhythmia recurrences The limited efficacy and proarrhythmic risks of antiarrhythmia agents have result ed in alternative therapeutic approaches . Radiofrequency ablation has been reported to be an effective treatment of patients with atrial fibrillation . However , there is no r and omized clinical trial comparing drug and radiofrequency ablation . The authors r and omized 30 patients with chronic atrial fibrillation refractory to medication into amiodarone and radiofrequency ablation .  The primary objective of this study was to compare the efficacy of amiodarone and radiofrequency ablation in the maintenance of sinus rhythm at 1 year after r and omization . Pulmonary vein isolation and linear ablation of right atrium was the technique used for radiofrequency ablation . There were no significant differences in baseline patient characteristics between the 2 groups . The results of this study showed that the probability of free from atrial fibrillation was better in the radiofrequency ablation group compared to amiodarone ( 78.6 % in the ablation group and 40 % in the amiodarone group , p = 0.018 ) . Radiofrequency ablation results in a significant reduction in symptoms relating to atrial fibrillation and a significant improvement in quality of life , whereas amiodarone had no significant effect on symptoms and quality of life . There was an ischemic stroke as a major complication related to radiofrequency ablation . Amiodarone was associated with adverse effects in 46.7 per cent of patients and needed discontinuation in 1 patient . In conclusion , radiofrequency ablation is an effective alternative treatment in patients with atrial fibrillation refractory to medication INTRODUCTION Pulmonary vein ( PV ) isolation for atrial fibrillation ( AF ) can be performed using a segmental ostial or a circumferential extra-ostial approach . The relative merits and potential limitations of each approach are currently debated . Here we report our early experience with each of these approaches , including their relative efficacy and safety . METHODS AND RESULTS Forty patients with drug-refractory AF underwent segmental ostial PV isolation and were compared to 40 consecutive patients who underwent PV isolation using a circumferential extra-ostial approach . The latter approach described here is novel in two aspects : ( 1 ) the endpoint for ablation was PV isolation and not only delay in left atrial to PV conduction time , and ( 2 ) isolation of the right and left PVs was achieved by a single encirclement of ipsilateral veins . At follow-up , 60 % of the patients in the segmental group were free of AF compared to 75 % of the patients in the circumferential group . There was one thromboembolic cerebrovascular complication during the ablation procedure in each group . CONCLUSION PV isolation using a circumferential extra-ostial approach , where the ipsilateral PVs are isolated together by one encircling line of block using electroanatomic mapping , is a technically feasible procedure . This approach is at least as effective and safe as the more established segmental ostial approach for AF ablation AIMS Circumferential pulmonary vein isolation ( CPVI ) has been reported to account for 30 % of atrial fibrillation ( AF ) recurrence after initial ablation , and pulmonary vein ( PV ) re-connection accounts for about 80 % of AF recurrence . There is no information in the literature whether early identification and treatment of acute PV conduction recovery during initial ablation has an impact on subsequent clinical results . The objective is to investigate the prevalence of acute PV conduction recovery during the observation time after PV isolation for paroxysmal AF , and to evaluate the impact of re-isolation treatment on clinical results . METHODS AND RESULTS Ninety cases with paroxysmal AF ( 51 males , mean age of 56.4 + /- 12.3 years ) were r and omized to 3 groups to undergo CPVI .  In Group A , there was no observation time post-ablation . In Group B , there was 30 min of observation time post-ablation . In Group C , there was 60 min of observation time post-ablation . All PV re-conduction was re-isolated at the end of the observation time . ECG and Holter monitors were used to evaluate the clinical effectiveness of ablation . All cases underwent the procedure successfully . The mean procedural time in Group A was significantly shorter than in Group B and Group C , but there was no significant difference on fluoroscopic time and PV isolation time among the three groups . In Group B , PV re-conduction occurred in 8 cases ( 25 % ) at 30 min post-isolation , in 10 cases ( 31.2 % ) at 60 min post-isolation for left PVs , and in 6 cases ( 18.8 % ) at 30 min post-isolation for right PVs . In Group C , PV re-conduction for left PVs occurred in 9 cases ( 30 % ) at 30 min post-isolation and in 11 cases ( 36.7 % ) at 60 min post-isolation ; for right PVs this occurred in 7 cases ( 23.3 % ) at 30 min post-isolation and in 8 cases ( 26.7 % ) at 60 min post-isolation . During a mean follow-up of 6.7 + /- 2.3 months , 17 cases ( 60.7 % ) in Group A , 27 cases ( 84.3 % ) in Group B , and 26 cases ( 86.7 % ) in Group C had no recurrence of atrial tachyarrhythmias , P = 0.04 . CONCLUSION The prevalence of acute PV conduction recovery was about 30 % after PV isolation , which mostly occurred within 30 min after initial isolation . Re-isolation of recovered PV conduction contributed to the improvement in the success rate of ablation for paroxysmal AF Background and objective Little is known about the outcome of  catheter ablation of  atrial fibrillation ( AF )  in patients with diabetes mellitus ( DM ) . We investigated the safety and efficacy of catheter ablation of AF  in patients with DM . Material s and methods Thirty one patients with DM from a group of 263 consecutive patients undergoing a first-time catheter ablation of AF procedure  were enrolled in a prospect i ve study . The ablation protocol ( guided by CARTO system ) consisted in two continuous circular lesions around ipsilateral pulmonary veins . Results The following clinical characteristics differed between DM and no-DM patients : age ( 62.0 ± 10.8 vs. 56.1 ± 10.6 years , P = 0.004 ) , longer AF history ( 9.6 ± 9.3 vs. 6.7 ± 6.3 years , P = 0.024 ) , significantly larger left atrium size ( 41.1 ± 7.8 vs. 38.3 ± 5.8 mm , P = 0.021 ) , hypertension ( 58.1 vs. 35.8 % , P = 0.018 ) and structural heart disease ( 67.7 vs. 43.5 % , P = 0.011 ) . Despite a similar AF recurrence rate in DM and no-DM patients ( 32.3 vs. 22.4 % , P = 0.240 ) , the ablation procedure was complicated in 28 patients ( 11 hematomas , three cardiac tamponades and three strokes ) and the incidence of complications was significantly higher in DM than in no-DM patients ( 29.0 vs. 8.2 % , respectively , P = 0.002 ) . Multivariate analysis showed that DM was an independent risk factor for complications occurrence ( odd ratio 5.936 , 95 % confidence interval 2.059 to 17.112 , P = 0.001 ) . Conclusions First catheter ablation of AF procedure in DM patients was equally efficacious than in no-DM patients . However , DM patients had a higher incidence of complications , mostly thrombotic or hemorrhagic
target: Contribution This systematic review found that radiofrequency ablation after a failed drug course maintained sinus rhythm more often than continuation of drug therapy alone .
  The benefits of maintaining sinus rhythm with antiarrhythmic drugs appeared to be offset by the serious adverse effects of the drugs .
background: Context Is radiofrequency catheter ablation a better alternative than medical therapy for patients with atrial fibrillation ?
  The Editors Atrial fibrillation is the most common sustained arrhythmia in clinical practice ( 1 ) .
  Its prevalence increases with age , from 0.1 % in people younger than 55 years to more than 9 % by 80 years of age ( 2 ) .
  The heavy burden of atrial fibrillation on morbidity , mortality , and health care re sources creates a pressing need for novel approaches to management .
  In some patients , adequate pharmacologic slowing of the ventricular response rate ( a rate-control strategy ) is sufficient to control symptoms .
  However , many patients remain symptomatic from the lack of organized atrial contraction and the persistent irregularity of the ventricular response in atrial fibrillation .
  In such patients , the appropriate treatment is restoration of normal sinus rhythm , achieved electrically or chemically ( a rhythm-control strategy ) ( 2 ) .
  Radiofrequency catheter ablation is a promising approach that offers the benefits of maintaining sinus rhythm without the adverse effects of antiarrhythmic drugs .
  Catheter ablation for atrial fibrillation is based on the underst and ing that electrical activity emanating from the pulmonary veins frequently serves as a trigger for atrial fibrillation .
  In the late 1990s , Hassaguerre and colleagues ( 5 ) observed that elimination of local electrograms at these foci with radiofrequency energy reduced the risk for recurrence of atrial fibrillation .
  Currently , the foundation of most atrial fibrillation ablation procedures is to target and electrically isolate the pulmonary veins ( 6 ) .
  This may be achieved by delivering lesions immediately outside the ostia of the pulmonary veins or along a wider area in the left atrium encircling the veins .
  Additional lesion sets have been used to ablate nonpulmonary vein triggers of atrial fibrillation and to target atrial areas thought to be responsible for maintaining atrial fibrillation ( 6 ) .
  These linear lesions may be created in the posterior left atrium , the roof of the left atrium , the interatrial septum , and the isthmus formed between the mitral annulus and the pulmonary vein or left atrial appendage .
  At present , the Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation , put forth by the Heart Rhythm Society and endorsed by several professional organizations , states that the foundation of most atrial fibrillation ablation procedures is to target the pulmonary veins , pulmonary vein antra , or both ( 6 ) .
  The panel advised us that 8-mmtip and irrigated-tip catheters are now the catheters of choice for radiofrequency ablation of atrial fibrillation in the United States .
  The conventional 4-mmtip catheter is rapidly being phased out of use for this indication .
  The following 3 key questions were formulated : 1 .
  What is the effect of radiofrequency catheter ablation on short-term ( 6 to 12 months ) and long-term ( > 12 months ) rhythm control ; rates of congestive heart failure ; changes in the size of the left atrium and ventricle ; rates of stroke ; quality of life ; avoiding anticoagulation ; and readmissions for paroxysmal , persistent , and long-st and ing persistent ( chronic ) atrial fibrillation ?
  2 .
  How does the effect of radiofrequency ablation  on rhythm control differ among the various techniques used ?
  3 .
  What are the short- and long-term complications and harms associated with radiofrequency ablation ?