title: Comparison of lesion formation between contact force-guided and non-guided circumferential pulmonary vein isolation: a prospective, randomized study. Comparison of contact force-guided procedure with non-contact force-guided procedure during left atrial mapping and pulmonary vein isolation: impact of contact force on recurrence of atrial fibrillation Randomized comparison of contact force-guided versus conventional circumferential pulmonary vein isolation of atrial fibrillation: prevalence, characteristics, and predictors of electrical reconnections and clinical outcomes EFFICAS II: optimization of catheter contact force improves outcome of pulmonary vein isolation for paroxysmal atrial fibrillation Use of a contact force-sensing ablation catheter with advanced catheter location significantly reduces fluoroscopy time and radiation dose in catheter ablation of atrial fibrillation. Clinical impact of an open-irrigated radiofrequency catheter with direct force measurement on atrial fibrillation ablation. Superior efficacy of pulmonary vein isolation with online contact force measurement persists after the learning period: a prospective case control study Optimizing radiofrequency ablation of paroxysmal and persistent atrial fibrillation by direct catheter force measurement-a case-matched comparison in 198 patients. Comparison of robotic and manual persistent AF ablation using catheter contact force sensing: an international multicenter registry study. Paroxysmal AF catheter ablation with a contact force sensing catheter: results of the prospective, multicenter SMART-AF trial. Randomized, Controlled Trial of the Safety and Effectiveness of a Contact Force–Sensing Irrigated Catheter for Ablation of Paroxysmal Atrial Fibrillation: Results of the TactiCath Contact Force Ablation Catheter Study for Atrial Fibrillation (TOCCASTAR) Study Real-time contact force sensing for pulmonary vein isolation in the setting of paroxysmal atrial fibrillation: procedural and 1-year results. A prospective study on safety of catheter ablation procedures: contact force guided ablation could reduce the risk of cardiac perforation. Comparison of antiarrhythmic drug therapy and radiofrequency catheter ablation in patients with paroxysmal atrial fibrillation: a randomized controlled trial.
abstract: BACKGROUND Contact force ( CF ) monitoring could be useful in accomplishing circumferential pulmonary vein ( PV ) isolation ( CPVI ) for atrial fibrillation ( AF ) . OBJECTIVE The purpose of this study was to compare procedure parameters and outcomes between CF-guided and non-guided CPVI . METHODS Thirty-eight consecutive AF patients ( mean age 60 ± 11 years , 28 paroxysmal AF ) undergoing CPVI were r and omized to non-CF-guided ( n = 19 ) and CF-guided ( n = 19 ) groups .  CPVI was performed with the ThermoCool SmartTouch catheter in both groups . The end-point was bidirectional block between the left atrium ( LA ) and PV . In the CF group , CF was kept between 10 and 20 g during CPVI , whereas in the non-CF group , all CF information was blanked . Radiofrequency energy at 30 W in the anterior and 25 W in the posterior LA wall was applied for 20 - 25 seconds at each point . RESULTS CPVI was successfully accomplished without any major complications in both groups . Mean CF in the non-CF and CF groups were 5.9 ± 4.5 g and 11.1 ± 4.3 g , respectively , for left-side CPVI , and 9.8 ± 6.6 g and 12.1 ± 4.8 g , respectively , for right-side CPVI ( both P < .001 ) . The procedure and fluoroscopy times  for CPVI in the non-CF and CF groups were 96 ± 39 minutes and 59 ± 16 minutes , respectively ( P < .001 ) , and 22 ± 63 seconds and 9 ± 20 seconds ( P = NS ) , respectively . Total number of residual conduction gaps was 6.3 ± 3.0 in the non-CF group and 2.8 ± 1.9 in the CF group ( P < .001 ) . During 6-month follow-up , 84.2 % of patients in the non-CF group and 94.7 % in the CF group were free from any atrial tachyarrhythmias ( P = .34 ) . CONCLUSION CF-guided CPVI  is effective in reducing procedure time and additional touch-up ablation and may improve long-term outcome Background The aim of this study was to evaluate the impact of contact force ( CF ) visualization on the incidence of low and high CF during left atrial ( LA ) mapping and pulmonary vein isolation ( PVI ) . Methods CF was assessed in 70 patients who underwent PVI .  Three highly experienced operators performed all procedures . The operators were blinded to CF in group A ( 35 patients ) , and CF was displayed in group B ( 35 patients ) . In group B , optimal CF was defined as mean CF between 10 and 39 g , and operators attempted to acquire points and ablate within this range . Results A total of 8401 mapping points were analyzed during LA mapping ( group A : 4104 , group B : 4297 ) . Low CF < 10 g and high CF ≥40 g were noted in a significantly larger number of points in group A ( 37.7 vs. 12.0 % , P < 0.001 ; 11.5 vs. 1.5 % , P < 0.001 ) . At the mitral isthmus and ridge areas , CF was significantly lower ( 7.7 vs. 12.2 g , P < 0.001 ; 5.3 vs. 11.7 g , P < 0.001 ) in group A than in group B. PVI was successfully achieved in all patients . There were significant site-dependent CF differences between the two groups . Optimal CF was achieved in significantly more applications in group B ( P < 0.001 ) . There was no significant difference in atrial fibrillation ( AF ) recurrence rates after a minimum follow-up of 1 year between the two groups in this cohort ( P = 0.24 ) . No significant peri-procedural complications occurred in either group . Conclusions CF visualization can assist in avoiding both low and high CF , which may have the potential to improve lesion formation and patient safety profile . In this study , CF-guided ablation did not affect AF recurrence Purpose We prospect ively investigated the differences in pulmonary vein reconnections ( PVRs ) and clinical outcomes between contact force (CF)-guided and conventional circumferential PV isolation ( CPVI ) of atrial fibrillation ( AF ) . Methods One hundred twenty consecutive AF patients ( 63 ± 10 years ; 88 males ) undergoing an initial CPVI were r and omized to ablation with a target CF of 20 g ( CF group ; n = 60 ) or that with operators blinded to the CF information ( blind group ; n = 60 ) . Results The CF group had fewer PVRs ( 0.67 ± 0.91/patient vs. 1.16 ± 1.16/patient ; P = 0.007 ) , a lower incidence of persistent PVRs ( 13.2 vs. 41.2 % ; P < 0.001 ) , and a shorter procedural time for the CPVI ( 50 vs. 56 min ; P = 0.019 ) than the blind group . The mean CF was higher in the CF group than the blind group ( 18.0 vs. 16.1 g ; P < 0.001 ) , with the most significant difference observed along the posterior right-sided PVs ( P-RPVs ) and anterior left-sided PVs ( A-LPVs ) . In logistic regression models , the mean CF was a negative predictor of PVRs along the P-RPVs and A-LPVs in the blind group ( odds ratios , 0.728 and 0.786 ; P < 0.001 and 0.007 ) , while no significant predictor was identified in the CF group or elsewhere in the blind group . In the Kaplan-Meier analysis , the arrhythmia-free survival rate at 12 months was 89.9 % in the CF group and 88.2 % in the blind group , respectively ( P = 0.624 ) . Conclusions CF-guided CPVI can reduce PVRs and the procedural time and be particularly beneficial along regions where a relatively low CF tends to be applied : the P-RPVs and A-LPVs . The comparable clinical outcomes may be due to the learning curve effect obtained by the CF-guided technique and repeated provocation of dormant PV conduction Aims A challenge of pulmonary vein isolation ( PVI ) in catheter ablation for paroxysmal atrial fibrillation ( PAF ) is electrical reconnection of the PV . EFFICAS I showed correlation between contact force ( CF ) parameters and PV durable isolation but no prospect i ve evaluation was made . EFFICAS II was a multicentre study to prospect ively assess the impact of CF guidance for an effective reduction of PVI gaps . Methods and results Pulmonary vein isolation using a radiofrequency ( RF ) ablation catheter with an integrated force sensor ( TactiCath ™ ) was performed in patients with PAF . Operators were provided EFFICAS I-based CF guidelines [ target 20 g , range 10–30 g , minimum 400 g s force-time integral ( FTI ) ] . Conduction gaps were assessed by remapping of PVs after 3 months , and gap rate was compared with EFFICAS I outcome . At follow up , 24 patients had 85 % of PVs remaining isolated , compared with 72 % in EFFICAS I ( P = 0.037 ) in which CF guidelines were not used . The remaining 15 % of gaps correlated to the number of catheter moves at creating the PVI line , quantified as Continuity Index . For PV lines with contiguous lesions and low catheter moves , durable isolation was 81 % in EFFICAS I and 98 % in EFFICAS II ( P = 0.005 ) . At index procedure , the number of lesions was reduced by 15 % in EFFICAS II vs. EFFICAS I. Conclusion The use of CF with the above guidelines and contiguous deployment of RF lesions in EFFICAS II study result ed in more durable PVI in catheter ablation of PAF AIMS The aim of this study was to evaluate the ' real-world ' impact of a novel contact force (CF)-sensing ( SmartTouch ™ , Biosense Webster , Diamond Bar , CA , USA ) catheter coupled with an advanced catheter location ( ACL ) system on fluoroscopy time and fluoroscopy dose during atrial fibrillation ( AF ) ablation . METHODS AND RESULTS This was a retrospective observational cohort study of prospect ively collected data of 1515 consecutive patients undergoing paroxysmal AF ( PAF ) and persistent AF ( PerAF ) ablation at a single institution between 2009 and 2014 . Patients undergoing AF ablation with the SmartTouch catheter and the ACL system ( SmartTouch group , n = 510 ) were compared with those undergoing AF ablation without this technology ( control group , n = 1005 ) . The primary outcomes were total fluoroscopy time ( min ) and fluoroscopy dose as measured by the dose-area product ( mGy cm(2 ) ) . Secondary endpoints included total procedure time , total ablation time , and major cardiac complications ( tamponade , pericardial effusion , and urgent cardiac surgery ) . The SmartTouch group had significantly lower fluoroscopy times ( 9.5 vs. 41 min , P < 0.001 ) , radiation doses ( 1044 vs. 3571 mGy cm(2 ) , P < 0.001 ) , and shorter procedural time ( 195 vs. 240 min , P < 0.001 ) when compared with the control group . This was statistically significant for both PAF and PerAF ablations and for both de novo and redo AF procedures . After a learning curve , a median fluoroscopy time of 3.5 min ( interquartile range 6 ) for all AF ablations was achieved . There was no difference in the rate of cardiac complications ( ∼ 1.5 % ) . CONCLUSION SmartTouch ™ CF-sensing catheter use with ACL ™ during AF ablation significantly reduces fluoroscopy times by 77 % , radiation dose by 71 % , and procedural time by 19 % but does not improve overall safety or the risk of cardiac complications BACKGROUND Electrode-tissue contact is crucial for adequate lesion formation in radiofrequency catheter ablation ( RFCA ) . OBJECTIVE We assessed the impact of direct catheter force measurement on acute procedural parameters during RFCA of atrial fibrillation ( AF ) . METHODS Fifty consecutive patients ( 28 male ) with paroxysmal AF who underwent their first procedure of circumferential pulmonary vein ( PV ) isolation ( PVI ) were assigned to either RFCA using ( 1 ) a st and ard 3.5-mm open-irrigated-tip catheter or ( 2 ) a catheter with contact force measurement capabilities . Using the endpoint of PVI with entry and exit block , acute procedural parameters were assessed . RESULTS Procedural data showed a remarkable decline in ablation time ( radiofrequency time needed for PVI ) from 50.5 ± 15.9 to 39.0 ± 11.0 minutes ( P = 0.007 ) with a reduction in overall procedure duration from 185 ± 46 to 154 ± 39 minutes ( P = 0.022 ) . In parallel , the total energy delivered could be significantly reduced from 70,926 ± 19,470 to 58,511 ± 14,655 Ws ( P = 0.019 ) . The number of acute PV reconnections declined from 36 % to 12 % ( P = 0.095 ) . CONCLUSIONS The use of contact force sensing technology is able to significantly reduce ablation and procedure times in PVI . In addition , energy delivery is substantially reduced by avoiding radiofrequency ablation in positions with insufficient surface contact . Procedural efficacy and safety of this new feature have to be evaluated in larger cohorts Purpose Use of online contact force ( CF ) measurement during circumferential pulmonary vein  ( PV )  isolation ( CPVI ) for atrial fibrillation ( AF ) has demonstrated improvements in procedural parameters and mid-term clinical outcome . However , it is unknown if experience gained with CF measuring catheters improves the efficacy of subsequent CPVI procedures performed without CF measurement . Methods This prospect i ve trial compared procedural results of CPVI performed without a CF measuring catheter to a control group performed with a CF measuring catheter , by an operator with prior experience with CF technology .. Results Thirty-six eligible paroxysmal ( n = 27 ) or persistent ( n = 9 ) AF patients were consecutively enrolled . Twelve patients underwent CPVI  with the non-CF catheter ( CF− group ) in a recall period and 24 with the CF catheter ( CF+ group ) . After the first circumferential lesion set , the number of PV pairs requiring additional touch-up lesions to achieve electrical isolation was significantly less in the CF+ group ( 2 of 48 ( 4.2 % ) vs. 7 of 24 ( 29.2 % ) in the CF+ and CF− groups , respectively , p = 0.005 ) . The procedure time was significantly lower in the CF+ group ( 117.9 ± 23.3 vs. 134.1 ± 25.3 min , p = 0.033 ) . Radiofrequency ( RF ) and fluoroscopy time did not differ between groups ( 31.5 ± 7.1 vs. 31.8 ± 7.0 min and 11.8 ± 5.6 vs. 11.0 ± 5.8 min in the CF+ and the CF− group , respectively ) Conclusions With the use of online CF measurement , PV isolation is more frequently complete following the first circumferential lesion set . A previous learning period with direct CF feedback is not a substitute for real-time direct CF measurement to maintain this advantage BACKGROUND Sufficient electrode-tissue contact is crucial for adequate lesion formation in radiofrequency catheter ablation ( RFCA ) . OBJECTIVE We assessed the impact of direct catheter force measurement on acute procedural parameters and outcome of RFCA for paroxysmal and persistent atrial fibrillation ( AF ) . METHODS Ninety-nine consecutive patients ( 70 % men ) with paroxysmal ( 63.6 % ) or persistent AF underwent left atrial RFCA using a 3.5-mm open-irrigated-tip ( OIT ) catheter with contact force measurement capabilities ( group 1 ) . For comparison a case-matched cohort with st and ard OIT catheters was used ( 99 patients ; group 2 ) . Case matching included gender , type of AF , number or RFCA procedures , and type of procedure . RESULTS Procedural data showed a significant decline in radiofrequency ablation time from 52 ± 20 to 44 ± 16 minutes ( P = 0.003 ) with a remarkable mean reduction in overall procedure time of 34 minutes ( P = 0.0001 ; 225.8 ± 53.1 vs 191.9 ± 53.3 minutes ) . In parallel , the total fluoroscopy time could be significantly reduced from 28.5 ± 11.0 to 19.9 ± 9.3 minutes ( P = 0.0001 ) as well as fluoroscopy dose from 74.1 ± 58.0 to 56.7 ± 38.9 Gy/cm(2 ) ( P = 0.016 ) . Periprocedural complications were similar in both groups . CONCLUSIONS The use of contact force sensing technology is able to significantly reduce ablation , procedure , and fluoroscopy times as well as dose in RFCA of AF in a mixed case-matched group of paroxysmal and persistent AF . Energy delivery is substantially reduced by avoiding radiofrequency ablation in positions with insufficient surface contact . Additionally 12-month outcome data showed increased efficacy . Such time saving and equally safe technology may have a relevant impact on laboratory management and increased cost effectiveness BACKGROUND Catheter-based contact force sensing ( CFS ) technology gives detailed information regarding contact between the catheter tip and myocardium . This may result in more effective ablation procedures . The primary objective of this study was comparison of remote robotic navigation ( RRN ) and Manual CFS ablation . The secondary objective was to compare CFS with non-CFS ablation for both navigation modes . METHODS Prospect i ve registries of consecutive cases undergoing their first ablation for persistent atrial fibrillation ( AF ) from six hospitals in the United Kingdom and South Africa were analyzed : 50 Manual/CFS and 50 RRN/CFS cases were included . Historical control non-CFS ablation patients were matched by propensity score , giving a total 200 patient cohort . RESULTS RRN/CFS was associated with improved single procedure 1-year success rates ( 64 % vs 36 % , P = 0.01 ) and shorter fluoroscopy times ( 41 % reduction , P < 0.0005 ) than Manual/CFS ablation , without any difference in procedure times ( P = 0.8 ) . The mean contact force was higher in RRN/CFS than Manual/CFS cases ( 16 [ 15 - 18 g ] vs 13 [ 12 - 15 g ] , respectively , P = 0.003 ) . Compared with non-CFS historical controls , CFS cases had higher 1-year success rates for RRN ( 64 % vs 36 % , P = 0.01 ) , but not Manual ablation ( 36 % vs 38 % , P = 1 ) . Procedure times were reduced for CFS cases ( 20 % , P < 0.005 both navigation modes ) , as were fluoroscopy times ( Manual : 43 % , RRN 83 % , P < 0.005 for both ) . There were no differences in rates of major or minor complications for either comparison ( P > 0.5 ) . CONCLUSIONS A combination of RRN and CFS is associated with improved success rates at 1 year and fluoroscopy times for persistent AF ablation , compared with Manual ablation and non-CFS RRN ablation BACKGROUND Catheter ablation is important for treatment of paroxysmal atrial fibrillation ( PAF ) . Limited animal and human studies suggest a correlation between electrode-tissue contact and radiofrequency lesion generation . OBJECTIVES The study sought to assess the safety and effectiveness of an irrigated , contact force (CF)-sensing catheter in the treatment of drug refractory symptomatic PAF . METHODS A prospect i ve , multicenter , nonr and omized study was conducted . Enrollment criteria included : ≥3 symptomatic episodes of PAF within 6 months of enrollment and failure of ≥1 antiarrhythmic drug ( Class I to IV ) . Ablation included pulmonary vein isolation with confirmed entrance block as procedural endpoint . RESULTS A total of 172 patients were enrolled at 21 sites , where 161 patients had a study catheter inserted and 160 patients underwent radiofrequency application . Procedural-related serious adverse events occurring within 7 days of the procedure included tamponade ( n = 4 ) , pericarditis ( n = 3 ) , heart block ( n = 1 , prior to radiofrequency application ) , and vascular access complications ( n = 4 ) . By Kaplan-Meier analyses , 12-month freedom from atrial fibrillation/atrial flutter/atrial tachycardia recurrence was 72.5 % . The average CF per procedure was 17.9 ± 9.4 g. When the CF employed was between investigator selected working ranges ≥80 % of the time during therapy , outcomes were 4.25 times more likely to be successful ( p = 0.0054 ; 95 % confidence interval : 1.53 to 11.79 ) . CONCLUSIONS The SMART-AF trial demonstrated that this irrigated CF-sensing catheter is safe and effective for the treatment of drug refractory symptomatic PAF , with no unanticipated device-related adverse events . The increased percent of time within investigator-targeted CF ranges correlates with increased freedom from arrhythmia recurrence . Stable CF during radiofrequency application increases the likelihood of 12-month success . ( THERMOCOOL ® SMARTTOUCH ® Catheter for Treatment of Symptomatic Paroxysmal Atrial Fibrillation ; NCT01385202 ) Background — Contact force ( CF ) is a major determinant of lesion size and transmurality and has the potential to improve efficacy of atrial fibrillation ablation . This study sought to evaluate the safety and effectiveness of a novel irrigated radiofrequency ablation catheter that measures real-time CF in the treatment of patients with paroxysmal atrial fibrillation . Methods and Results — A total of 300 patients with symptomatic , drug-refractory , paroxysmal atrial fibrillation were enrolled in a prospect i ve , multicenter , r and omized , controlled trial and r and omized to radiofrequency ablation with either a novel CF-sensing catheter or a non-CF catheter ( control ) . The primary effectiveness end point consisted of acute electrical isolation of all pulmonary veins and freedom from recurrent symptomatic atrial arrhythmia off all antiarrhythmic drugs at 12 months . The primary safety end point included device-related serious adverse events . End points were powered to show noninferiority . All pulmonary veins were isolated in both groups . Effectiveness was achieved in 67.8 % and 69.4 % of subjects in the CF and control arms , respectively ( absolute difference , −1.6 % ; lower limit of 1-sided 95 % confidence interval , −10.7 % ; P=0.0073 for noninferiority ) . When the CF arm was stratified into optimal CF ( ≥90 % ablations with ≥10 g ) and nonoptimal CF groups , effectiveness was achieved in 75.9 % versus 58.1 % , respectively ( P=0.018 ) . The primary safety end point occurred in 1.97 % and 1.40 % of CF patients and control subjects , respectively ( absolute difference , 0.57 % ; upper limit of 1-sided 95 % confidence interval , 3.61 % ; P=0.0004 for noninferiority ) . Conclusions — The CF ablation catheter met the primary safety and effectiveness end points . Additionally , optimal CF was associated with improved effectiveness . Clinical Trial Registration — http://www . clinical trials.gov . Unique identifier : NCT01278953 INTRODUCTION The additional benefit of contact force ( CF ) technology during pulmonary vein isolation ( PVI ) for paroxysmal atrial fibrillation ( AF ) to improve mid-term clinical outcome is unclear . METHODS AND RESULTS Eligible patients with symptomatic paroxysmal AF were enrolled in this prospect i ve trial , comparing circular antral catheter ablation ( guided by Carto 3 System , Biosense Webster ) using either a new open-irrigated CF catheter ( SmartTouch Thermocool , Biosense Webster ) ( CF group ) or a non-CF open-irrigated catheter ( EZ Steer Thermocool , Biosense Webster ) ( control group ) . Overall , 30 patients were enrolled in each group , with a st and ardized 12-month follow-up , free of antiarrhythmic therapy . Demographic , cardiovascular and anatomic characteristics were similar in both groups . Though complete PVI was eventually achieved in all cases in both groups , success using an exclusive anatomic approach was 80.0 % in CF group versus 36.7 % in control group ( P < 0.0001 ) . CF use was associated with significant reductions in fluoroscopy exposure ( P < 0.01 ) and radiofrequency time ( P = 0.01 ) . The incidence rates of AF recurrence were 10.5 % ( 95 % CI , 1.38 - 22.4 ) in the CF group , and 35.9 % ( 95 % CI , 12.4 - 59.4 ) in the control group ( log rank test , P = 0.04 ) . After adjustment on potential confounders , the use of CF catheter was found to be associated with a lower AF recurrence ( OR 0.18 , 95 % CI 0.04 - 0.94 , P = 0.04 ) . CONCLUSION Our findings suggest a potential benefit of real-time CF sensing technology , in reducing AF recurrence during the first year after PVI BACKGROUND Contact force ( CF ) sensing catheters provide advantages with regard to safety and efficacy . This study aim ed to evaluate if CF catheters reduce cardiac perforations and other major complications and offer equal safety compared to the magnetic navigation system ( MNS ) . METHODS Data from 1.517 ablation procedures from our prospect i ve registry was analyzed . Ablations were performed using either CF guided catheters ( CF group , n=248 ) , non-CF catheters ( NCF group , n=813 ) , or MNS ( n=456 ) . Four subgroups were analyzed : atrial fibrillation ( AF , n=557 ) , supraventricular tachycardia ( SVT , n=715 ) , ventricular tachycardia ( VT , n=190 ) and patients with congenital heart defects ( CHD , n=55 ) . The primary endpoint of this study was incidence of cardiac perforation . Secondary endpoints were major and minor complications within 30 days of the procedure . RESULTS Complications occurred in 11.3 % ( n=172 ) of the procedures . In 2.8 % ( n=43 ) a major complication occurred , 0.9 % ( n=13 ) had a perforation , 8.5 % ( n=129 ) had a minor complication and 2 patients died ( 0.1 % ) . No cardiac perforation occurred in the CF group , which was significantly different from NCF procedures ( 0.0 % vs. 1.6 % ; relative risk 0.76 , 95 % CI 0.74 - 0.79 , P=0.031 ) and equal to MNS ( 0.0 % ) . This was also observed in the AF subgroup ( 0.0 % vs. 3.3 % ; RR 0.67 , 95 % CI 0.63 - 0.72 , P=0.021 ) , and the occurrence of major complications was lower for CF versus NCF procedures ( 2.1 % vs. 7.8 % , P=0.010 ) . CONCLUSIONS CF-guided catheter ablation is superior to NCF with regard to procedural safety and avoidance of cardiac perforation . This difference is due to a reduction of cardiac perforation and major complications in the AF subgroup CONTEXT Antiarrhythmic drugs are commonly used for prevention of recurrent atrial fibrillation ( AF ) despite inconsistent efficacy and frequent adverse effects . Catheter ablation has been proposed as an alternative treatment for paroxysmal AF . OBJECTIVE To determine the efficacy of catheter ablation compared with antiarrhythmic drug therapy ( ADT ) in treating symptomatic paroxysmal AF . DESIGN , SETTING , AND PARTICIPANTS A prospect i ve , multicenter , r and omized ( 2:1 ) , unblinded , Bayesian- design ed study conducted at 19 hospitals of 167 patients who did not respond to at least 1 antiarrhythmic drug and who experienced at least 3 AF episodes within 6 months before r and omization . Enrollment occurred between October 25 , 2004 , and October 11 , 2007 , with the last follow-up on January 19 , 2009 . INTERVENTION Catheter ablation ( n = 106 ) or ADT ( n = 61 ) , with assessment for effectiveness in a comparable 9-month follow-up period . MAIN OUTCOME MEASURES Time to protocol -defined treatment failure . The proportion of patients who experienced major treatment-related adverse events within 30 days of catheter ablation or ADT was also reported . RESULTS At the end of the 9-month effectiveness evaluation period , 66 % of patients in the catheter ablation group remained free from protocol -defined treatment failure compared with 16 % of patients treated with ADT . The hazard ratio of catheter ablation to ADT was 0.30 ( 95 % confidence interval , 0.19 - 0.47 ; P < .001 ) . Major 30-day treatment-related adverse events occurred in 5 of 57 patients ( 8.8 % ) treated with ADT and 5 of 103 patients ( 4.9 % ) treated with catheter ablation .  Mean quality of life scores improved significantly in patients treated by catheter ablation compared with ADT at 3 months ; improvement was maintained during the course of the study . CONCLUSION Among patients with paroxysmal AF who had not responded to at least 1 antiarrhythmic drug , the use of catheter ablation compared with ADT result ed in a longer time to treatment failure during the 9-month follow-up period . TRIAL REGISTRATION clinical trials.gov Identifier : NCT00116428
target: CF-sensing catheter ablation of AF can reduce the incidence of major complications and generate better outcomes compared with NCF-sensing catheters during the 12-month follow-up period
background: Contact force ( CF ) monitoring can be useful in accomplishing circumferential pulmonary vein ( PV ) isolation for atrial fibrillation ( AF ) .
  This meta- analysis aim ed to assess the efficacy and safety of a CF-sensing catheter in treating AF .