title: Is Pulmonary Vein Isolation Necessary for Curing Atrial Fibrillation? German ablation registry: Cryoballoon vs. radiofrequency ablation in paroxysmal atrial fibrillation--One-year outcome data. Cryoballoon vs. radiofrequency contact force ablation for paroxysmal atrial fibrillation: a propensity score analysis Acute and Long-Term Outcomes of Catheter Ablation of Atrial Fibrillation Using the Second-Generation Cryoballoon versus Open-Irrigated Radiofrequency: A Multicenter Experience. Incidence and characteristics of phrenic nerve palsy following pulmonary vein isolation with the second-generation as compared with the first-generation cryoballoon in 360 consecutive patients. Cryoballoon versus radiofrequency catheter ablation for paroxysmal atrial fibrillation. Outcomes after cryoballoon or radiofrequency ablation for persistent atrial fibrillation: a multicentric propensity-score matched study Second‐generation cryoballoon ablation for treatment of persistent atrial fibrillation: Three‐year outcome and predictors of recurrence after a single procedure Radiofrequency Ablation of Atrial Fibrillation: Is the Persistence of All Intraprocedural Targets Necessary for Long-Term Maintenance of Sinus Rhythm? Pulmonary venous isolation by antral ablation with a large cryoballoon for treatment of paroxysmal and persistent atrial fibrillation: medium-term outcomes and non-randomised comparison with pulmonary venous isolation by radiofrequency ablation Real-time assessment of pulmonary vein disconnection during cryoablation of atrial fibrillation: can it be 'achieved' in almost all cases? Two-Year Follow-Up after Contact Force Sensing Radiofrequency Catheter and Second-Generation Cryoballoon Ablation for Paroxysmal Atrial Fibrillation: A Comparative Single Centre Study Long-term comparison of cryoballoon and radiofrequency ablation of paroxysmal atrial fibrillation: a propensity score matched analysis. Early Recurrence After Pulmonary Vein Isolation of Paroxysmal Atrial Fibrillation With Different Ablation Technologies - Prospective Comparison of Radiofrequency vs. Second-Generation Cryoballoon Ablation. Circumferential pulmonary vein isolation as index procedure for persistent atrial fibrillation: a comparison between radiofrequency catheter ablation and second-generation cryoballoon ablation. Ablation of atrial fibrillation with cryoballoon or duty-cycled radiofrequency pulmonary vein ablation catheter: a randomized controlled study comparing the clinical outcome and safety; the AF-COR study. Point-by-Point Radiofrequency Ablation Versus the Cryoballoon or a Novel Combined Approach: A Randomized Trial Comparing 3 Methods of Pulmonary Vein Isolation for Paroxysmal Atrial Fibrillation (The Cryo Versus RF Trial). Visualization of multiple catheters with electroanatomical mapping reduces X-ray exposure during atrial fibrillation ablation. Contact-force guided radiofrequency vs. second-generation balloon cryotherapy for pulmonary vein isolation in patients with paroxysmal atrial fibrillation-a prospective evaluation. The COR trial: a randomized study with continuous rhythm monitoring to compare the efficacy of cryoenergy and radiofrequency for pulmonary vein isolation. Cryoballoon vs. open irrigated radiofrequency ablation for paroxysmal atrial fibrillation: long-term FreezeAF outcomes Cellular damage, platelet activation, and inflammatory response after pulmonary vein isolation: a randomized study comparing radiofrequency ablation with cryoablation. Histopathology of cryoballoon ablation-induced phrenic nerve injury. Is the time between first diagnosis of paroxysmal atrial fibrillation and cryoballoon ablation a predictor of efficacy? Results from a multicentre comparison of cryoballoon vs. radiofrequency ablation for paroxysmal atrial fibrillation: is cryoablation more reproducible? Cryoballoon or Radiofrequency Ablation for Paroxysmal Atrial Fibrillation. Asymptomatic atrial fibrillation: clinical correlates, management, and outcomes in the EORP-AF Pilot General Registry.
abstract: Background —Pulmonary veins ( PVs ) play a pivotal role in initiating and perpetuating  atrial fibrillation ( AF ) . We investigated if PV electrical isolation from the left atrium is required for curing AF . Methods and Result —Fifty-one patients with paroxysmal or persistent AF underwent circumferential radiofrequency ablation of PV ostia performed with an anatomic approach . The end point of the ablation procedure was the recording of low peak-to-peak bipolar potentials ( < 0.1 mV ) inside the lesions . Left atrium pacing was used to assess the conduction between the PVs and the left atrium . During a mean follow-up period of 16.6±3.9 months , 41 patients ( 80.4 % ) were free of atrial arrhythmias . When patients with and without AF recurrence were analyzed , no significant difference was observed in the mean number of PVs in which the ablation end point was reached ( 3.4±1.2 versus 3.7±0.87 ) and PVs isolated ( 1.5±1.4 versus 1.6±1 ) . We noted that , although in 29 of 41 patients ( 71 % ) without AF recurrence , the ablation end point was reached in all PVs mapped , it was only possible to demonstrate the isolation of all PVs mapped in 2 patients . On the other h and , in 7 of 10 patients ( 70 % ) with AF recurrence , the ablation end point was reached in all PVs mapped , whereas one patient had all PVs isolated . Conclusions —Our findings show that with the use of a pure anatomic approach , it is possible to prevent AF in > 80 % of patients undergoing catheter ablation . Moreover , the isolation of PVs is not crucial for curing AF BACKGROUND Although radiofrequency ( RF ) ablation has long been the st and ard of care for atrial fibrillation ( AF ) ablation , cryoballoon technology has emerged as a feasible approach with promising results . Prospect i ve multicenter registry data referring to both ablation technologies in AF ablation are lacking so far . OBJECTIVE The purpose of this study was to report data from the German ablation registry with respect to efficacy and safety in pulmonary vein ablation with different energy sources for paroxysmal AF after 1-year follow-up . METHODS A total of 2306 patients with symptomatic paroxysmal AF from the German ablation registry were included in this analysis . The cohort was divided into two groups according to the ablation energy source used : cryoballoon and RF ablation .  MACCE was defined as a combination of death , myocardial infa rct ion , or stroke . RESULTS AF recurrence rate after a single ablation procedure at 1 year follow-up was not significantly different between the two groups ( 45.8 % after cryoablation and 45.4 % after RF ablation , P = .87 ) . Also , the rate of patients without AF recurrence and free of antiarrhythmic drug at 12-month follow-up was similar ( cryoablation 44.2 % and RF 41.4 % , P = .25 ) . MACCE occurred with an incidence of 0.7 % within 500 days after cryoablation and 1.4 % after RF ablation ( P = .30 ) . Persistent phrenic nerve palsy was more common after cryoablation compared to RF ablation ( 1.1 % vs. 0.3 % , P < .05 ) . CONCLUSION AF recurrence rate at 1-year follow-up was similar in RF ablation compared to cryoablation , whereas the spectrum and relevance of complications were significantly different between the two ablation methods . This finding might influence the choice of ablation method offered to the individual paroxysmal AF patient Background Radiofrequency and cryoballoon pulmonary vein isolation are common approaches for paroxysmal atrial fibrillation treatment , showing similar results in recent multicenter studies , including heterogeneous tools and protocol s. The aim of this study is to compare prospect ively in a single , high-volume center the outcome of paroxysmal atrial fibrillation ablation performed specifically by second-generation cryoballoon or contact force radiofrequency ablation . Methods Consecutive patients scheduled for paroxysmal atrial fibrillation transcatheter ablation have been included and prospect ively followed up . Aim ing to reduce potential bias deriving from baseline characteristics , a propensity score matching analysis has been performed to analyze safety and efficacy outcomes . Results Out of consecutive patients undergoing atrial fibrillation transcatheter ablation between January 2015 and December 2016 , 46 patients approached by cryoablation  were matched 1 : 1 by propensity score to a similar population treated by last-generation radiofrequency ablation .  Freedom from atrial fibrillation after 12 months ( 76 vs. 78 % , P = 0.804 ) and incidence of complications ( 4 vs. 6 % , P = 0.168 ) did not differ between the two groups . Radiological exposure was higher for the cryoballoon group ( 11 vs. 4 min , P < 0.001 ) , whereas procedural duration did not differ ( P = 0.174 ) . Aim ing to assess the potential impact of a learning curve in patients undergoing cryoablation , the first-third of patients ( n = 15 ) were compared with the remaining , reporting longer radiological exposure ( P < 0.001 ) , but similar safety and efficacy . Conclusion In this propensity score analysis , last-generation cryoballoon and radiofrequency catheters for atrial fibrillation ablation present similar efficacy and safety .  Cryoablation requires longer fluoroscopy exposure compared with radiofrequency , although this is reduced by increased experience INTRODUCTION There are limited comparative data on catheter ablation of atrial fibrillation ( CAAF ) using the second-generation cryoballoon ( CB-2 ) versus point-by-point radiofrequency ( RF ) . This study examines the acute/long-term CAAF outcomes using these 2 strategies . METHODS AND RESULTS In this multicenter , retrospective , nonr and omized analysis , procedural and clinical outcomes of 1,196 patients ( 76 % with paroxysmal AF ) undergoing CAAF using CB-2 ( n = 773 ) and open-irrigated , non-force sensing RF ( n = 423 ) were evaluated . Pulmonary vein isolation was achieved in 98 % with CB-2 and 99 % with RF ( P = 0.168 ) . CB-2 was associated with shorter ablation time ( 40 ± 14 min vs. 66 ± 26 min ; P < 0.001 ) and procedure time ( 145 ± 49 minutes vs. 188 ± 42 minutes ; P < 0.001 ) , but greater fluoroscopic utilization ( 29 ± 13 minutes vs. 23 ± 14 minutes ; P < 0.001 ) . While transient ( 7.6 % vs. 0 % ; P < 0.001 ) and persistent ( 1.2 % vs. 0 % ; P = 0.026 ) phrenic nerve palsy occurred exclusively with CB-2 , other adverse event rates were similar between CB-2 ( 1.6 % ) and RF ( 2.6 % ) ; P = 0.207 . However , freedom from AF/atrial flutter/tachycardia at 12 months following a single procedure without antiarrhythmic therapy was greater with CB-2 ( 76.6 % ) versus RF ( 60.4 % ) ; P < 0.001 . While this difference was evident in patients with paroxysmal AF ( P < 0.001 ) , it did not reach significance in those with persistent AF ( P = 0.089 ) . Additionally , CB-2 was associated with reduced long-term need for antiarrhythmic therapy ( 16.7 % vs. 22.0 % ; P = 0.024 ) and repeat ablations ( 14.6 % vs. 24.1 % ; P < 0.001 ) . CONCLUSION In this multicenter , retrospective , nonr and omized study , CAAF using CB-2 coupled with RF as occasionally required was associated with greater freedom from atrial arrhythmias at 12 months following a single procedure without antiarrhythmic therapy when compared to open-irrigated , non-force sensing RF , alone AIMS The second-generation cryoballoon ( CB2 ) with increased surface cooling has recently become available . The aim was to investigate the incidence and characteristics of phrenic nerve palsy ( PNP ) during pulmonary vein isolation ( PVI ) using the CB2 as compared with the first-generation balloon ( CB1 ) . METHODS AND RESULTS A total of 360 consecutive patients with atrial fibrillation underwent PVI with the CB1 ( 106 patients ) or the CB2 ( 254 patients ) .  Right PN function was monitored by continuous stimulation and palpation during septal PV ablation . Persistent PNP ( present at discharge ) occurred in 2.8 and 1.9 % ( P = 0.63 ) of patients , transient PNP ( full recovery before discharge ) in 5.9 and 3.8 % ( P = 0.41 ) of patients in the CB2 and CB1 group , respectively . Phrenic nerve palsy during ablation at the right inferior PV was observed in 0 % ( CB1 ) and 4.3 % ( CB2 , P = 0.03 ) of patients . Using the CB2 , a trend of reduced incidence of persistent PNP over quartiles of consecutive patients was observed [ 4.8 % ( Q1 ) vs. 0 % ( Q4 ) ; P = 0.077 ] . At the culprit PV , PNP occurred after 3.5 ± 2.1 ( CB1 ) and 1.1 ± 0.4 applications ( CB2 ; P = 0.036 ) . Complete recovery of PN function occurred after 29 ± 11 ( CB1 ) and 259 ± 137 days ( CB2 ; P = 0.004 ) . CONCLUSIONS The rate of transient/persistent PNP associated with the use of the CB2 was 5.9 and 2.8 % , respectively . Time to restitution of PN function was longer using the CB2 BACKGROUND Catheter ablation is an established treatment for atrial fibrillation ( AF ) .  Cryoballoon ablation ( CBA ) has emerged as an alternative to radiofrequency ablation ( RFA ) . However , there are few data comparing these modalities for treatment of paroxysmal AF ( pAF ) in the U.S. POPULATION The purpose of this study was to compare procedural times , safety , and efficacy of CBA against RFA . METHODS A single-center prospect i ve cohort study evaluated patients who underwent catheter ablation for pAF using CBA or RFA between January 1 , 2010 and October 31 , 2013 . Patients with prior ablation and those without rhythm follow-up for at least 3 months were excluded . The primary end point was freedom from AF , atrial flutter , and atrial tachycardia ( FFAF ) > 30 seconds after a 3-month blanking period without requirement for antiarrhythmic drugs . We also compared rates of successful pulmonary vein isolation ( PVI ) , fluoroscopy and procedure times , and major complication rates . RESULTS A total of 201 patients were included ( CBA = 101 , RFA = 100 ) . The rate of successful PVI was 99.3 % in CBA versus 97.4 % in RFA ( P = 0.08 ) . Procedure times were shorter with CBA ( 192.9 ± 44.0 minutes vs 283.7 ± 78.0 minutes , P < 0.001 ) as well as total fluoroscopy times ( 46.0 ± 22.4 minutes vs 73.0 ± 30.1 minutes , P < 0.001 ) . Overall complication rates were equivalent ; however , fewer cardiac perforations occurred with CBA ( 0 % vs 4 % , P = 0.042 ) . The 1-year FFAF rates were 60.3 % for CBA and 61.1 % for RFA ( log rank P = 0.93 ) . CONCLUSION CBA was associated with equivalent 1-year FFAF rate as RFA for pAF . Procedure and fluoroscopy times were shorter for CBA and fewer cardiac perforations occurred Purpose Recent data show no benefit of additional ablation beyond pulmonary vein isolation ( PVI ) in persistent atrial fibrillation ( AF ) . Evidence suggests that radiofrequency energy ( RF ) and cryoballoon ( CRYO ) have comparable efficacy for PVI . We aim ed to assess the outcomes after a single catheter ablation procedure , comparing PVI using CRYO vs. RF ablation for PVI plus additional ablation in a cohort of patients with persistent AF . Methods In this prospect i ve multicenter propensity score-matched comparison , 59 consecutive patients undergoing CRYO ablation of persistent AF were matched to 59 patients treated with RF from November 2010 to June 2012 . Results During a mean follow-up of 15.6 ± 11.5 months , 43.2 % of patients presented atrial arrhythmia relapse after a blanking period of 3 months , which was comparable between the two groups ( 40.7 % in CRYO vs. 45.8 % in RF , Log rank P = 0.14 ; HR = 0.67 , 95 % CI 0.38–1.16 , P = 0.15 ) , despite the fact that 52.5 % of RF patients add additional complex fractionated atrial electrogram ablation , as well as left atrial linear ablation in over two-thirds ( roof line in 67.8 % and mitral isthmus in 32.2 % ) . On multivariate Cox regression , only AF duration in years ( HR = 1.10 , 95 % CI 1.01–1.10 , P = 0.04 ) was a predictor of relapse . Patients undergoing RF ablation presented a numerically , but non-significantly , lower complication rate ( 6.8 vs 10.2 % , P = 0.51 ) . Conclusion In our multicenter experience , freedom from atrial arrhythmias was comparable among matched patients treated with CRYO and RF , despite non-significant trends in favor of RF in terms of complications , at the cost of longer procedure times INTRODUCTION Data on long-term outcomes of cryoballoon ( CB ) ablation for treatment of persistent atrial fibrillation ( AF ) are sparse . Here , we report the first 3-year follow-up results and predictors of success for catheter ablation using the second-generation CB in patients with persistent AF . METHODS AND RESULTS For this prospect i ve observational study , we enrolled 101 patients ablated with the second-generation CB at our institution . The endpoint was the first documented recurrence ( > 30 seconds ) of AF , atrial flutter , or atrial tachycardia after a 3-month blanking period . Follow-up data were collected during outpatient clinic visits and included Holter-ECG recordings . The impact of several variables on recurrence was evaluated by means of univariate and multivariate analyses and Cox proportional hazards regression models . After a median follow-up of 37 ( 31 of 42 ) months , recurrence was documented in 30 patients ( 29.7 % ) . The median procedure and fluoroscopy times were 120 ( 102 of 147 ) and 20 ( 16 of 27 ) minutes , respectively . Phrenic nerve palsy occurred in 2.0 % of the patients . Among the 30 patients who experienced recurrence , 16 underwent repeat ablation in radiofrequency technique . Cox regression analysis showed that left atrial area > 21 cm2 and AF history duration > 2 years independently predicted recurrence . CONCLUSIONS Sinus rhythm was maintained in a substantial proportion of patients even 3 years after CB ablation . Patients with a nonenlarged left atrium and short AF history had the best outcome Background — Several approaches have been developed for radiofrequency catheter ablation of atrial fibrillation , but the correct intraprocedural end point is still under debate , and few data exist about the destiny of ablation lesions over time . The aim of the present study was to evaluate the long-term maintenance of intraprocedural end points of ablation procedures . Methods and Results — Inclusion criteria were ( 1 ) a previous ablation procedure of pulmonary vein ( PV ) encircling performed for drug-refractory persistent atrial fibrillation ; ( 2 ) a “ complete ” intraprocedural end point , which consisted of voltage abatement inside the lesions , PV disconnection , and exit-block pacing from inside the lesions , attained in all PVs ; and ( 3 ) stable sinus rhythm documented during a minimum follow-up of 2.5 years after the procedure . Twenty volunteers were selected ( 12 males , mean age 59±7 years ) and underwent a repeat electrophysiological study . After a follow-up of 36.4±4.7 months , complete voltage abatement was maintained around 32 PVs ( 40.0 % ) , PV disconnection persisted in 12 ( 37.5 % ) of the previously isolated PVs , and exit block was present in 39 PVs ( 48.7 % ) . Ten patients who underwent a redo ablation procedure because of recurrences of atrial fibrillation were used as the control group . Differences in intraprocedural end-point maintenance between the 2 groups were not statistically significant . Conclusions — Common intraprocedural end points such as voltage abatement , PV disconnection , and exit block persist only in a limited number of patients , even when the outcome is favorable during follow-up . Further investigation will be required to determine whether such data will have implication s for ablation strategies Background To prevent  atrial fibrillation ( AF ) recurrence after catheter ablation , pulmonary venous isolation ( PVI ) at an antral level is more effective than segmental ostial ablation . Cryoablation around the pulmonary venous ( PV ) ostia for AF therapy is potentially safer compared to radiofrequency ablation ( RFA ) . The aim of this study was to investigate the efficacy of a strategy using a large cryoablation balloon to perform antral cryoablation with ‘ touch-up ’ ostial cryoablation for PVI in patients with paroxysmal and persistent AF . Methods Paroxysmal and persistent AF patients undergoing their first left atrial ablation were recruited . After cryoballoon therapy , each PV was assessed for isolation and if necessary , treated with focal ostial cryoablation until PVI was achieved . Follow-up with Holter monitoring was performed . Clinical outcomes of the cryoablation protocol were compared , with consecutive patients undergoing PVI by RFA . Results 124 consecutive patients underwent cryoablation . 77 % of paroxysmal and 48 % of persistent AF subjects were free from AF at 12 months after a single procedure . Over the same time period , 53 consecutive paroxysmal AF subjects underwent PVI with RFA and at 12 months , 72 % were free from AF at 12 months ( p = NS ) . There were too few persistent AF subjects ( n=8 ) undergoing solely PVI by RFA as a comparison group . Procedural and fluoroscopic times during cryoablation were significantly shorter than RFA . Conclusions PV isolation can be achieved in less than 2 h by a simple cryoablation protocol with excellent results after a single intervention , particularly for paroxysmal AF AIM Real-time assessment of pulmonary vein ( PV ) disconnection is possible using an inner circular mapping catheter during cryoablation of atrial fibrillation ( AF ) . However , it has been recently demonstrated that such continuous monitoring may only be possible in < 50 % of PVs . We hypothesized that a stepwise mapping approach , including pacing manoeuvres , could optimize monitoring of real-time PV disconnection during ablation . METHODS AND RESULTS Single-centre , prospect i ve observational study ( NCT01843465 ) including 34 consecutive eligible patients ( 128 PVs ) undergoing a first procedure of cryoballoon ablation of AF using the Artic Front Advance ( ® ) 28 mm catheter and a 20 mm diameter Achieve ( ® ) catheter ( AC )  in all cases . Monitoring of real-time entrance block was possible , when AC was maintained in the st and ard position ( distal to the tip of the Artic Front Advance ( ® ) catheter ) in 47 ( 36.7 % ) PVs . In an additional 63 cases ( 49.2 % ) , such monitoring was possible after moving AC to a more proximal position and using different torqueing movements . Finally , using supplemental systematic pacing manoeuvres to test exit block , real-time assessment of PV disconnection was possible in 15 ( 11.7 % ) more PVs . Overall , real-time assessment of PV disconnection was possible in 97.7 % of cases , after a mean duration of 48.6 ± 33.0 s. CONCLUSION Our results suggest that optimal use of the AC , with a systematic stepwise mapping approach , may dramatically improve the real-time monitoring of PV disconnection during AF cryoablation Background . There are little comparative data on catheter ablation of paroxysmal atrial fibrillation ( AF ) using the contact force radiofrequency ( CF-RF ) catheter versus the second-generation cryoballoon ( CB2 ) . Methods and results . This is a single center , retrospective , nonr and omized study of 98 patients with symptomatic , drug-refractory paroxysmal AF who underwent their first PVI ablation using either the CB2 ( n = 40 ) or CF-RF ( n = 58 ) . The mean age was 60 years with 63 % men , a mean LA size of 42 mm . The procedure duration ( 74 ± 17 versus 120 ± 49 minutes p < 0.05 ) was shorter for CB2 group ; the fluoroscopy time ( 14 ± 17 versus 16 ± 5 minutes , p = 0.45 ) was similar . Complete PVI was achieved in 96 % of patients with RF-CF and 98 % with CB2 . Phrenic nerve palsies ( 2 transient and 1 persistent ) occurred exclusively in the CB2 group and 1 severe , nonlethal complication ( pericardial tamponade ) occurred in the CF-RF group . At 24-month follow-up , the success rate , defined as freedom from AF/atrial tachycardia ( AT ) after a single procedure without antiarrhythmic drug , was comparable in CF-RF group and CB2 group ( 65.5 % versus 67 % , resp . , log rank p = 0.54 ) . Conclusion . Both the CB2 and the RF-CF ablation appeared safe ; the success rate at 2 years was comparable between both technologies BACKGROUND Although radiofrequency ( RF ) and cryoballoon ( CB ) based technologies for pulmonary vein isolation ( PVI ) have both individually been demonstrated to be effective and safe for the treatment of paroxysmal AF , head-to-head comparisons are lacking . The purpose of this study was to compare the outcome of cryoballoon versus radiofrequency ablation in patients with paroxysmal atrial fibrillation undergoing pulmonary vein isolation . METHODS Out of a prospect i ve registry of 327 patients undergoing PVI , 208 patients ( age 58±11 years , ejection fraction 59±6 % , left atrial size 39±6 mm ) with paroxysmal AF were identified . The presented data set was obtained by 1:1 propensity score matching and contained 142 patients undergoing CB-PVI or RF-PVI in conjunction with a 3D mapping system , respectively . We compared single procedure efficacy of the two methods using a Cox proportional hazards model . RESULTS After a mean follow-up of 28 months and a single procedure , AF recurred in 37 of 71 ( 52 % ) in the CB-PVI group and in 31 of 71 patients ( 44 % ) in the RF-PVI group ( HR [ 95 % CI]=1.19 [ 0.74 , 1.92 ] , p=0.48 ) . Recurrence of AF for PVI using solely the CB was observed in 23 of 51 ( 45 % ) patients and in 23 of 51 ( 45 % ) patients in the corresponding RF-PVI group ( HR [ 95 % CI]=0.93 [ 0.52 , 1.66 ] , p=0.81 ) . Complication rate was not different between the groups . CONCLUSION A propensity score matched comparison between CB-PVI and RF-PVI using a 3D-mapping system for AF ablation showed similar long-term success rates BACKGROUND Inflammation plays a prominent role in the etiology of the early recurrence of  atrial fibrillation ( ERAF ) . We prospect ively compared the proportion of ERAF and time-course patterns of biomarkers between radiofrequency ( RF ) and cryoballoon ( CB ) ablation . METHODS AND RESULTS We enrolled 82 consecutive paroxysmal AF patients undergoing pulmonary vein ( PV ) isolation , performed with either a 28-mm 2nd-generation CB and 3-min freeze technique or point-by-point RF ablation .  Each group had 41 patients . In the RF group , all PVs were successfully isolated with 28.9 ± 6.5 min of RF delivery . In the CB group , a mean of 5.3 ± 1.4 applications/patient was delivered . The proportion of ERAF was similar between the groups . The time-course patterns significantly differed between the groups for high-sensitivity C-reactive protein ( hs-CRP ) value ( P=0.006 ) and myocardial injury markers ( P<0.0001 ) . Greater myocardial injury was observed in the CB than in the RF group ( P<0.0001 ) , whereas the peak hs-CRP value was comparable between the groups . The 2-day post-procedure hs-CRP value was the sole factor correlating with ERAF as identified by the multivariable analysis ( hazard ratio 1.697 ; 95 % confidence interval , 1.005 - 2.865 ; P=0.048 ) in the RF , but not the CB group . CONCLUSIONS The proportion of ERAF was comparable after RF and 2nd-generation CB ablation . Despite CB ablation exhibiting greater myocardial injury than RF ablation , the inflammatory responses were comparable between the groups . The inflammatory response extent predicted ERAF post-RF ablation but not post-CB ablation AIMS To assess the 1 year efficacy of pulmonary vein isolation ( PVI ) as index procedure for persistent atrial fibrillation ( PersAF ) comparing conventional radiofrequency irrigated-tip catheter ablation ( RFCA ) using contact-force technology and ablation using the second-generation cryoballoon ( CB-AdvA ) . METHODS AND RESULTS One hundred consecutive patients ( 74 male , 74 % ; mean age 62.4 ± 9.6 years ) with drug-refractory PersAF undergoing PVI using RFCA and CB-AdvA were enrolled . Follow-up was based on outpatient clinic visits including Holter-electrocardiograms . Recurrence of atrial tachyarrhythmias ( ATas ) was defined as a symptomatic or documented episode > 30 s. Among 100 patients , 50 underwent RFCA whereas 50 CB-AdvA.  Mean procedure and fluoroscopy times were 90.5 ± 41.7 vs. 140.2 ± 46.9 min and 14.5 ± 6.6 vs. 19.8 ± 6.8 min in the CB-Adv and in the RFCA group , respectively ( P < 0.01 ) . At 1 year follow-up , after a 3 months blanking period ( BP ) , freedom from ATas off-drugs after a single procedure was 60 % ( 28/50 patients ) in the CB-Adv and 56 % ( 27/50 patients ) in the RFCA group ( P = 0.71 ) . Multivariate analysis demonstrated that PersAF duration ( P = 0.01 ) and relapses during BP ( P = 0.02 ) were independent predictors of ATa recurrences following the index procedure . CONCLUSION Freedom from ATas following PersAF ablation with RFCA and CB-Adv is comparable at 1 year follow-up after a single procedure . Ablation with the CB-Adv is associated with shorter procedure time and radiation exposure as compared with RFCA . Atrial tachyarrhythmias occurrence during BP and longer time of PersAF seem to be significant predictors of arrhythmia recurrences after the index procedure AIMS The urge to facilitate the atrial fibrillation ( AF ) ablation procedure has led to the development of new ablation catheters specifically design ed as ' one-shot tools ' for pulmonary vein isolation ( PVI ) . The purpose of this study was to compare the efficacy , safety , and procedure times for two such catheters using different energy sources . METHODS AND RESULTS One hundred and ten patients , referred for ablation of paroxysmal or persistent AF , were r and omized to treatment with either the cryoballoon or the circular multipolar duty-cycled radiofrequency-based pulmonary vein ablation catheter ( PVAC ) .  Complete PVI was achieved in 98 vs. 93 % patients in the cryoballoon and PVAC group , respectively , with complication rates of 8 vs. 2 % ( P = 0.2 ) . Complete freedom from AF , without antiarrhythmic drugs , after one single ablation procedure was seen in 46 % in the cryoballoon vs. 34 % after 12 months ( P = 0.2 ) . Procedure times were comparable , but fluoroscopy time was shorter for the cryoballoon ( 32 ± 16 min ) than for the PVAC procedures ( 47 ± 17 min ) ( P < 0.001 ) . A significant improvement of quality of life ( QoL ) and arrhythmia-related symptoms was seen in both groups after ablation . CONCLUSION Both catheters proved comparably effective and safe in achieving acute PVI , apart from the shorter fluoroscopy times achieved with the cryoballoon . At follow-up , there was no statistically significant difference between the groups regarding freedom from AF and clinical success . The QoL increased to the same levels as for the general Swedish population in both groups INTRODUCTION Catheter ablation of paroxysmal AF using the Cryoballoon ( CRYO ) has yielded similar success rates to conventional wide encirclement using radiofrequency catheter ablation ( RFCA ) , but r and omized data are lacking . Pilot data suggested a high success rate with a combined approach ( COMBINED ) using wide encirclement with RFCA followed by 2 CRYO applications to each vein . We compared these 3 strategies in a r and omized controlled trial . METHODS AND RESULTS Patients undergoing first time paroxysmal AF ablation were r and omized to RFCA , CRYO , or COMBINED . Patients were followed up at 3 , 6 , and 12 months with 7 days of ambulatory ECG monitoring . Success was defined as freedom from arrhythmia without antiarrhythmic drugs after a single procedure . A total of 237 patients were r and omized . Success at 1 year was achieved in 47 % in the RFCA group , 67 % in the CRYO group , and 76 % in the COMBINED group ( P < 0.001 for RFCA vs. CRYO , P<0.001 for RFCA vs. COMBINED , and P = 0.220 for CRYO vs. COMBINED ) . Procedure time was 211 ( IQR 174 - 256 ) minutes for RFCA compared to 167 ( 136 - 202 ) minutes for CRYO and 278 ( 243 - 327 ) minutes for COMBINED ( P < 0.001 for RFCA vs. COMBINED , RFCA vs. CRYO , and CRYO vs. COMBINED groups ) . CONCLUSIONS Pulmonary vein isolation for paroxysmal AF is faster with CRYO and results in a higher single procedure success rate than conventional point by point RFCA . The COMBINED approach was not superior to CRYO alone AIMS Atrial fibrillation ( AF ) ablation still requires long procedural time and high radiation exposure with its related risk for the patient and the operators . This study was design ed to compare three different approaches of AF ablation to verify the hypothesis that image integration with electroanatomic mapping allows minimal use of fluoroscopy . Therefore , we evaluated the procedure and fluoroscopy times of ablation using three imaging modalities : conventional fluoroscopy , image integration electroanatomic mapping , and a new electroanatomic mapping system that provides visualization of multiple catheters . METHODS AND RESULTS One hundred and twenty patients with symptomatic refractory AF were enrolled in the study . Patients were r and omly assigned to fluoroscopy alone ( Group A , 40 patients ) , electroanatomic integration ( Cartomerge ® , Group B , 40 patients ) , and electroanatomic integration plus catheters visualization ( Carto ® 3 System , Group C , 40 patients ) guided procedures . The ablation procedure aim ed at isolating the pulmonary veins and creating lesion lines at the left atrial roof and left isthmus . Procedure and fluoroscopy parameters were recorded in all patients . Total procedure time and skin to catheter positioning time did not significantly differ between the groups . Total fluoroscopy time was statistically different between all three groups ( Group A , 18'09″±5'00″ ; Group B , 9'48″±3'41″ ; Group C , 2'28″±1'40″ ; P<0.001 ) . A significant difference was noted in ablation fluoroscopy time between all groups ( P<0.001 ) , mainly due to shortened fluoroscopy time in Group B ( 7'34″±3'15″ ) and Group C ( 0'21″±0'31″ ) when compared with Group A ( 16'07″±5'04″ ) . CONCLUSION Image integration and , to a larger extent , visualization of multiple catheters allowed a minimal use of fluoroscopy in transcatheter AF ablation AIMS In the setting of paroxysmal atrial fibrillation ( AF ) , there are no available data comparing the mid-term outcome of patients undergoing pulmonary vein isolation ( PVI ) catheter ablation using contact-force (CF)-guided radiofrequency ( RF ) vs. second-generation balloon cryotherapy . METHODS AND RESULTS Prospect i ve single-centre evaluation , carried out from March 2011 to February 2013 , comparing CF radiofrequency ( Thermocool ( ® ) SmartTouch ™ , Biosense Webster , Inc. ) ( CF group ) with cryoballoon ablation ( A rct ic Front Advance ™ 28 mm cryoballoon , Medtronic , Inc. ) ( CB group ) , in regards to procedural safety and efficacy , as well as recurrence at 12 months . Overall , 150 consecutive patients were enrolled ( 75 in each group ) . The characteristics of patients of both the groups were similar ( 61.2 ± 9.9 years , women 25.3 % , mean AF duration 4.1 ± 4.0 years , mean CHA2DS2-VASc score 1.4 ± 1.3 , mean HAS-BLED 1.4 ± 0.6 ) . Duration of the procedure was significantly lower in the CF group ( 110.7 ± 32.5 vs. 134.5 ± 48.3 min , P = 0.001 ) , with a lower duration of fluoroscopy ( 21.5 ± 8.5 vs. 25.3 ± 9.9 min , P = 0.017 ) and X-ray exposure ( 4748 ± 2411 cGy cm² vs. 7734 ± 5361 cGy cm² , P = 0.001 ) . In contrast , no significant difference was found regarding significant procedural complication ( 2.7 vs. 1.3 % in CF and CB groups , respectively ; P = 0.56 ) , and PVI was eventually achieved in all cases . At 12 months , AF recurrence occurred in 11 patients ( 14.7 % ) in the CB group and in 9 patients ( 12.0 % ) in the CF group ( HR = 1.20 95 % CI 0.50 - 2.90 ; log rank P = 0.682 ) . CONCLUSIONS Our preliminary findings suggest that CF-guided radiofrequency and cryotherapy present very similar performances in the setting of paroxysmal AF catheter ablation BACKGROUND Results from r and omized trials design ed to compare cryoenergy with radiofrequency for pulmonary vein ( PV ) isolation are lacking . OBJECTIVE To compare the efficacy of a simplified strategy for PV cryoablation ( group C ) vs PV isolation with open-irrigated radiofrequency catheters ( group R ) . METHODS Fifty patients with paroxysmal atrial fibrillation ( AF ) and 4 independent PVs received a Reveal XT implantable cardiac monitor and were r and omized to group C or group R. In group C , PV ablation was done with a single A rct ic Front balloon ( 23 or 28 mm ) per patient and two 300-second applications per PV . No further applications were delivered to close residual conduction gaps . In group R , bidirectional PV conduction block was pursued with Lasso and Navistar ThermoCool catheters and the CARTO system . The primary end point was the proportion of patients remaining free from AF recurrences ≥2 minutes without taking antiarrhythmic drugs 12 months after ablation . RESULTS The primary end point was met by 12 ( 48 % ) patients in group C and 25 ( 68 % ) patients in group R ( odds ratio 0.43 ; P = .05 ) . This difference disappeared after adjustment for acute procedural outcome . In patients for whom all 4 PVs were blocked at the end of the procedure , there was no difference between group C and group R in the primary end point ( 67 % vs 68 % ; P = .94 ) . CONCLUSIONS The efficacy of the simplified strategy for PV cryoablation tested in this study is inferior to PV isolation using open-irrigated radiofrequency catheters with electrophysiological and electroanatomical guidance . Complete PV conduction block is critical to the success of AF ablation Background Effective treatment of paroxysmal atrial fibrillation ( AF ) is essential for reducing the risk of stroke and heart failure .  Cryoballoon ( CB ) ablation has been developed as an alternative to the use of radiofrequency ( RF ) energy for electrical isolation of the pulmonary veins . Herein , we provide long-term data regarding the efficacy of CB ablation in comparison to RF . Methods FreezeAF was a r and omised non-inferiority study comparing CB ablation with RF ablation for the treatment of patients with drug-refractory paroxysmal AF . Procedural success for the long-term follow-up ( 30 months ) was defined as freedom from AF with an absence of persistent complications . Results Of the 315 patients that were r and omised and received catheter ablation , 292 ( 92.7 % ) completed the 30-month follow-up ( 147 in the RF group and 145 in the CB group ) . The baseline characteristics of the RF and CB groups were similar . Single-procedure success was achieved by 40 % of patients in the RF group and 42 % of the CB group ( p < 0.001 for non-inferiority ) . When including re-do procedures in the analysis , the multiple procedure success rate was 72 % in the RF group and 76 % in the CB group . Conclusion The data provide long-term evidence that CB ablation is non-inferior to RF ablation , with high proportions of patients reporting freedom from AF 30 months after the index procedure . Trial registration Clinical Trials.gov Identifier : NCT00774566 ; first registered October 16 , 2008 ; first patient included October 20 , 2008 BACKGROUND Experimental data suggest that use of cryoablation in pulmonary vein isolation ( PVI ) is associated with less cell damage and less thrombus formation compared to radiofrequency ( RF ) energy . OBJECTIVE The purpose of this study was to test the hypothesis that cryoablation significantly reduces markers of cell damage , platelet activation , and inflammation in patients undergoing PVI for treatment of atrial fibrillation ( AF ) . METHODS Sixty patients with symptomatic drug-resistant AF ( age 56 ± 9 years , 48 males , 38 with paroxysmal AF ) were r and omly assigned to undergo PVI using either an open irrigated-tip RF catheter or a cryoballoon . Markers of cell damage ( high-sensitive troponin T [ hs-TnT ] , microparticles ) , platelet activation ( platelet reactivity by aggregometry , expression of platelet surface proteins P-selectin and activated glycoprotein [ GP ] IIb/IIIa ) , and inflammatory response ( high-sensitive C-reactive protein [ hs-CRP ] ) were determined before and up to 48 hours after the procedure . RESULTS PVI result ed in a significant rise in hs-TnT , microparticles , markers of platelet activation , and hs-CRP over time , with distinct temporal patterns for each parameter . However , after Bonferroni correction for repeated measurements , no significant differences were noted in these parameters between patients treated with cryoablation or RF energy . Procedural time was significantly shorter in patients treated with cryoballoon ( 177 ± 30 minutes vs 200 ± 46 minutes , P = .03 ) , with no differences in fluoroscopic time , periprocedural complications , or success rate . CONCLUSION Cryoablation and RF energy result in a comparable rise of markers of cell damage , platelet activation and inflammatory response . The data do not support the concept of an improved safety profile for cryoablation in PVI INTRODUCTION Hemi-diaphragmatic paralysis is the most common complication associated with cryoballoon ablation for atrial fibrillation , yet the histopathology of phrenic nerve injury has not been well described . METHODS AND RESULTS A pre clinical r and omized study was conducted to characterize the histopathology of phrenic nerve injury induced by cryoballoon ablation and assess the potential for electromyographic ( EMG ) monitoring to limit phrenic nerve damage . Thirty-two dogs underwent cryoballoon ablation of the right superior pulmonary vein with the objective of inducing phrenic nerve injury . Animals were r and omized 1:1 to st and ard monitoring ( i.e. , interruption of ablation upon reduction in diaphragmatic motion ) versus EMG guidance ( i.e. , cessation of ablation upon a 30 % reduction in the diaphragmatic compound motor action potential [ CMAP ] amplitude ) . The acute procedural endpoint was achieved in all dogs . Phrenic nerve injury was characterized by Wallerian degeneration , with subperineural injury to large myelinated axons and evidence of axonal regeneration . The degree of phrenic nerve injury paralleled the reduction in CMAP amplitude ( P = 0.007 ) . Animals r and omized to EMG guidance had a lower incidence of acute hemi-diaphragmatic paralysis ( 50 % vs 100 % ; P = 0.001 ) , persistent paralysis at 30 days ( 21 % vs 75 % ; multivariate odds ratio 0.12 , 95 % confidence interval [ 0.02 , 0.69 ] , P = 0.017 ) , and a lesser severity of histologic injury ( P = 0.001 ) . Mature pulmonary vein ablation lesion characteristics , including circumferentiality and transmurality , were similar in both groups . CONCLUSION Phrenic nerve injury induced by cryoballoon ablation is axonal in nature and characterized by Wallerian degeneration , with potential for recovery . An EMG-guided approach is superior to st and ard monitoring in limiting phrenic nerve damage Aims Cryoablation is an indicated therapy for the treatment of recurrent atrial fibrillation through pulmonary vein isolation ; however , the optimal time between first diagnosis of atrial fibrillation and cryoablation is still unknown . We aim ed to assess the clinical efficacy and safety of early versus later treatment of patients with paroxysmal atrial fibrillation by cryoablation .  Methods Five hundred and ten patients underwent atrial fibrillation cryoablation and were prospect ively followed for at least 6 months in 43 Italian cardiology centers . The population was divided into two groups according to the time since the first diagnosis of atrial fibrillation until the index cryoablation procedure . An early-treatment group had an elapsed time of 15 months or less from atrial fibrillation diagnosis until cryoablation , and the late-treatment group had an elapsed time of greater than 15 months . During the evaluation , clinical efficacy was defined as atrial fibrillation recurrence outside a l and mark 90-day blanking period , and safety was defined as the reporting of all procedure-related complications . Results In the total cohort , cryoablation was performed after a median of 36 months from the point of the patient diagnosis with drug refractory symptomatic recurrent atrial fibrillation . The early-treatment group was composed of 130 ( 25 % ) patients , whereas the late-treatment group had 380 ( 75 % ) patients . Both cohorts had similar baseline clinical characteristics . Of 510 patients , 22 had a complication related to the procedure with no difference between the two groups . Multivariable analysis showed that the risk of atrial fibrillation recurrence was significantly higher in the late-treatment group ( hazard ratio : 1.77 ; 95 % confidence interval 1.00 - 3.13 ) Conclusion In our multicenter observational examination , cryoablation was well tolerated and effective in the treatment of patients with drug refractory symptomatic paroxysmal atrial fibrillation . Reducing the time between diagnosis and ablation brought about a treatment that had a lower risk of atrial fibrillation recurrence with no change in safety . ( Italian Clinical Service Project : NCT01007474 ) Aim Cryoballoon ablation ( Cryoballoon ) has emerged as a new alternative for the treatment of  symptomatic drug-refractory atrial fibrillation ( AF ) . Whether the results of Cryoballoon are more reproducible than those of radiofrequency ( RF ) ablation remains to be proved . Methods and results A total of 860 consecutive patients undergoing a first ablation procedure for paroxysmal AF ( 467 treated with RF and 393 treated with Cryoballoon ) were selected from a prospect i ve multicentre survey of AF ablation ( FrenchAF ) .  Radiofrequency and Cryoballoon were compared regarding mid-term efficacy and safety . During a median follow-up of 14 months ( interquartile range 8–23 ) , patients treated with Cryoballoon displayed similar rates of freedom from atrial arrhythmia relapse in centres performing this technique ( 68–80 % at 18 months ) . However , in centres performing RF , a greater heterogeneity in procedural results was observed ( 46–79 % were free from atrial arrhythmia relapse at 18 months ) . On multivariate analysis , Cryoballoon ( HR = 0.47 , 95 % CI 0.35–0.65 , P < 0.001 ) and annual AF ablation caseload ( HR = 0.87 per every 100 AF ablation procedures per year ; 95 % CI 0.80–0.96 , P = 0.003 ) were independent predictors of procedural success . However , on sensitivity analysis , according to the ablation method , annual AF ablation caseload predicted only sinus rhythm maintenance in the subgroup of patients treated with RF . Analysis of interoperator results with Cryoballoon and RF confirmed lower reproducibility of RF , but suggested that besides caseload , other operator-related factors may play a role . Conclusion Cryoballoon seems to be less operator-dependent and more reproducible than RF in the setting of paroxysmal AF ablation BACKGROUND Current guidelines recommend pulmonary-vein isolation by means of catheter ablation as treatment for drug-refractory paroxysmal atrial fibrillation .  Radiofrequency ablation is the most common method , and cryoballoon ablation is the second most frequently used technology . METHODS We conducted a multicenter , r and omized trial to determine whether cryoballoon ablation was noninferior to radiofrequency ablation in symptomatic patients with drug-refractory paroxysmal atrial fibrillation . The primary efficacy end point in a time-to-event analysis was the first documented clinical failure ( recurrence of atrial fibrillation , occurrence of atrial flutter or atrial tachycardia , use of antiarrhythmic drugs , or repeat ablation ) following a 90-day period after the index ablation . The noninferiority margin was prespecified as a hazard ratio of 1.43 . The primary safety end point was a composite of death , cerebrovascular events , or serious treatment-related adverse events . RESULTS A total of 762 patients underwent r and omization ( 378 assigned to cryoballoon ablation and 384 assigned to radiofrequency ablation ) . The mean duration of follow-up was 1.5 years . The primary efficacy end point occurred in 138 patients in the cryoballoon group and in 143 in the radiofrequency group ( 1-year Kaplan-Meier event rate estimates , 34.6 % and 35.9 % , respectively ; hazard ratio , 0.96 ; 95 % confidence interval [ CI ] , 0.76 to 1.22 ; P<0.001 for noninferiority ) . The primary safety end point occurred in 40 patients in the cryoballoon group and in 51 patients in the radiofrequency group ( 1-year Kaplan-Meier event rate estimates , 10.2 % and 12.8 % , respectively ; hazard ratio , 0.78 ; 95 % CI , 0.52 to 1.18 ; P=0.24 ) . CONCLUSIONS In this r and omized trial , cryoballoon ablation was noninferior to radiofrequency ablation with respect to efficacy for the treatment of patients with drug-refractory paroxysmal atrial fibrillation , and there was no significant difference between the two methods with regard to overall safety . ( Funded by Medtronic ; FIRE AND ICE Clinical Trials.gov number , NCT01490814 . ) OBJECTIVE Atrial fibrillation is often asymptomatic , but outcomes require further characterization . The study objective was to investigate the clinical presentation , management , and outcomes in asymptomatic and symptomatic patients with atrial fibrillation who were prospect ively enrolled in the EurObservational Research Programme - Atrial Fibrillation ( EORP-AF ) Pilot General Registry . METHODS A total of 3119 patients were enrolled , and 1237 ( 39.7 % ) were asymptomatic ( European Heart Rhythm Association [ EHRA ] score I ) . Among symptomatic patients , 963 ( 51.2 % ) had mild symptoms ( EHRA score II ) and 919 ( 48.8 % ) had severe or disabling symptoms ( EHRA III-IV ) . Permanent atrial fibrillation was 3-fold more common in asymptomatic patients than in symptomatic patients . RESULTS On multivariate analysis , male gender ( odds ratio [ OR ] , 1.630 ; 95 % confidence interval [ CI ] , 1.384 - 1.921 ) , older age ( OR , 1.019 ; 95 % CI , 1.012 - 1.026 ) , previous myocardial infa rct ion ( OR , 1.681 ; 95 % CI , 1.350 - 2.093 ) , and limited physical activity ( OR , 1.757 ; 95 % CI , 1.495 - 2.064 ) were associated significantly with asymptomatic ( EHRA I ) atrial fibrillation . Fully asymptomatic atrial fibrillation ( absence of current and previous symptoms ) was present in 520 patients ( 16.7 % ) and was associated independently with male gender , age , and previous myocardial infa rct ion . Appropriate guideline -based prescription of oral anticoagulants  was lower in these patients , and  aspirin  was prescribed more frequently . Mortality at 1 year was more than 2-fold higher in asymptomatic patients compared with symptomatic patients ( 9.4 % vs 4.2 % , P < .0001 ) and was associated independently with older age and comorbidities , including chronic kidney disease and chronic heart failure . CONCLUSIONS Asymptomatic atrial fibrillation is common in daily cardiology practice and is associated with elderly age , more comorbidities , and high thromboembolic risks . A higher 1-year mortality was found in asymptomatic patients compared with symptomatic patients
target: Conclusion In patients with paroxysmal atrial fibrillation  , cryoballoon and radiofrequency ablation produce similar results in terms of freedom from recurrent atrial fibrillation or atrial tachyarrhythmias but with a different safety profile , being cryoballoon ablation less associated with cardiac complications but more likely to cause phrenic nerve palsy
background: Aims To perform an up date d meta- analysis to assess efficacy , safety and technical performance of pulmonary vein isolation using cryoballoon or radiofrequency catheter ablation in patients with paroxysmal or persistent atrial fibrillation .