Cryoballoon vs. radiofrequency contact force ablation for paroxysmal atrial fibrillation: a propensity score analysis Circumferential pulmonary vein isolation with the cryoballoon technique results from a prospective 3-center study. Cryoballoon versus radiofrequency for pulmonary vein re-isolation after a failed initial ablation procedure in patients with paroxysmal atrial fibrillation. 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. 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 Cryoballoon ablation of pulmonary veins for paroxysmal atrial fibrillation: first results of the North American Arctic Front (STOP AF) pivotal trial. Rationale and Design of FIRE AND ICE: A multicenter randomized trial comparing efficacy and safety of pulmonary vein isolation using a cryoballoon versus radiofrequency ablation with 3D-reconstruction. Long-term comparison of cryoballoon and radiofrequency ablation of paroxysmal atrial fibrillation: a propensity score matched analysis. Randomised clinical trial of cryoballoon versus irrigated radio frequency catheter ablation for atrial fibrillation—the effect of double short versus standard exposure cryoablation duration during pulmonary vein isolation (CIRCA-DOSE): methods and rationale Circumferential pulmonary vein isolation as index procedure for persistent atrial fibrillation: a comparison between radiofrequency catheter ablation and second-generation cryoballoon ablation. Cryoballoon or Radiofrequency Ablation for Paroxysmal Atrial Fibrillation. The effectiveness of a high output/short duration radiofrequency current application technique in segmental pulmonary vein isolation for atrial fibrillation. Small or Large Isolation Areas Around the Pulmonary Veins for the Treatment of Atrial Fibrillation?: Results From a Prospective Randomized Study Mesh ablator vs. cryoballoon pulmonary vein ablation of symptomatic paroxysmal atrial fibrillation: results of the MACPAF study. The COR trial: a randomized study with continuous rhythm monitoring to compare the efficacy of cryoenergy and radiofrequency for pulmonary vein isolation. A new nonfluoroscopic navigation system to guide pulmonary vein isolation. 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).
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 OBJECTIVES The purpose of this study was to investigate the efficacy safety of the novel cryoballoon device ( A rct ic Front , Cryocath , Quebec , Canada ) . BACKGROUND Antral pulmonary vein ( PV ) ablation with radiofrequency energy is widely used as a strategy for catheter ablation of paroxysmal atrial fibrillation ( PAF ) . A novel double lumen cryoballoon catheter was design ed for circumferential pulmonary vein isolation ( PVI ) with the cryoablation technique . METHODS We consecutively enrolled 346 patients with symptomatic , drug refractory paroxysmal ( n = 293 ) or persistent ( n = 53 ) atrial fibrillation ( AF ) . In all patients , PVI of all targeted PVs was the therapeutic aim . The primary end points of this nonr and omized study were : 1 ) acute isolation rate of targeted PV ; and 2 ) first electrocardiogram-documented recurrence of AF . The secondary end point was occurrence of PV stenosis or atrio-esophageal fistula . RESULTS The 1,360 of 1,403 PVs ( 97 % ) were targeted with balloons or balloons in combination with the use of Freezor Max ( Cryocath ) . We found that ablation with the cryoballoon result ed in maintenance of sinus rhythm in 74 % of patients with PAF and 42 % of patients with persistent AF . No PV narrowing occurred . The most frequent complication was right phrenic nerve palsy observed during cryoballoon ablation at the right superior PV . CONCLUSIONS Pulmonary vein isolation with a new cryoballoon technique is feasible . Sinus rhythm can be maintained in the majority of patients with PAF by circumferential PVI using a cryoballoon ablation system . Cryoablation was less effective in patients with persistent AF than in patients with PAF AIM Catheter ablation of paroxysmal atrial fibrillation ( PAF ) is associated with an important risk of early and late recurrence , necessitating repeat ablation procedures . The aim of this prospect i ve r and omized patient-blind study was to compare the efficacy and safety of cryoballoon ( Cryo ) versus radiofrequency ( RF ) ablation of PAF after failed initial RF ablation procedure . METHODS Patients with a history of symptomatic PAF after a previous failed first RF ablation procedure were eligible for this study . Patients were r and omized to Cryo or RF redo ablation . The primary endpoint of the study was recurrence of atrial tachyarrhythmia , including AF and left atrial flutter/tachycardia , after a second ablation procedure at 1 year of follow-up . All patients were implanted with a cardiac monitor ( Reveal XT , Medtronic ) to continuously track the cardiac rhythm . Patients with an AF burden ( AF% ) ≤ 0.5 % were considered AF-free ( Responders ) , while those with an AF% > 0.5 % were classified as patients with AF recurrences ( non-Responders ) . RESULTS Eighty patients with AF recurrences after a first RF pulmonary vein isolation ( PVI ) were r and omized to Cryo ( N = 40 ) or to RF ( N = 40 ) . Electrical potentials were recorded in 77 mapped PVs ( 1.9 ± 0.8 per patient ) in Cryo Group and 72 PVs ( 1.7 ± 0.8 per patient ) in RF Group ( P = 0.62 ) , all of which were targeted . In Cryo group , 68 ( 88 % ) of the 77 PVs were re-isolated using only Cryo technique ; the remaining 9 PVs were re-isolated using RF . In RF group , all 72 PVs were successfully re-isolated ( P = 0.003 vs Cryo ) . By intention-to-treat , 23 ( 58 % ) RF patients were AF-free vs 17 ( 43 % ) Cryo patients on no antiarrhythmic drugs at 1 year ( P = 0.06 ) . Three patients had temporary phrenic nerve paralysis in the Cryo group ; the RF group had no complications . Of the 29 patients who had only Cryo PVI without any RF ablation , 11 ( 38 % ) were AF-free vs 20 ( 59 % ) of the 34 patients who had RF only ( P = 0.021 ) . CONCLUSION When patients require a redo pulmonary vein isolation ablation procedure for recurrent PAF , RF appears to be the preferred energy source relative to Cryo 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 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 OBJECTIVES This study sought to assess the safety and effectiveness of a novel cryoballoon ablation technology design ed to achieve single-delivery pulmonary vein ( PV ) isolation . BACKGROUND St and ard radiofrequency ablation is effective in eliminating atrial fibrillation ( AF ) but requires multiple lesion delivery at the risk of significant complications . METHODS Patients with documented symptomatic paroxysmal AF and previously failed therapy with ≥ 1 membrane active antiarrhythmic drug underwent 2:1 r and omization to either cryoballoon ablation ( n = 163 ) or drug therapy ( n = 82 ) . A 90-day blanking period allowed for optimization of antiarrhythmic drug therapy and reablation if necessary . Effectiveness of the cryoablation procedure versus drug therapy was determined at 12 months . RESULTS Patients had highly symptomatic AF ( 78 % paroxysmal , 22 % early persistent ) and experienced failure of at least one antiarrhythmic drug . Cryoablation produced acute isolation of three or more PVs in 98.2 % and all four PVs in 97.6 % of patients . PVs isolation was achieved with the balloon catheter alone in 83 % . At 12 months , treatment success was 69.9 % ( 114 of 163 ) of cryoblation patients compared with 7.3 % of antiarrhythmic drug patients ( absolute difference , 62.6 % [ p < 0.001 ] ) . Sixty-five ( 79 % ) drug-treated patients crossed over to cryoablation during 12 months of study follow-up due to recurrent , symptomatic AF , constituting drug treatment failure . There were 7 of the result ing 228 cryoablated patients ( 3.1 % ) with a > 75 % reduction in PV area during 12 months of follow-up . Twenty-nine of 259 procedures ( 11.2 % ) were associated with phrenic nerve palsy as determined by radiographic screening ; 25 of these had resolved by 12 months . Cryoablation patients had significantly improved symptoms at 12 months . CONCLUSIONS The STOP AF trial demonstrated that cryoballoon ablation is a safe and effective alternative to antiarrhythmic medication for the treatment of patients with symptomatic paroxysmal AF , for whom at least one antiarrhythmic drug has failed , with risks within accepted st and ards for ablation therapy . ( A Clinical Study of the A rct ic Front Cryoablation Balloon for the Treatment of Paroxysmal Atrial Fibrillation [ Stop AF ] ; NCT00523978 ) BACKGROUND Atrial fibrillation ( AF ) is the most common sustained cardiac arrhythmia imposing substantial morbidity and mortality . Catheter-based pulmonary vein isolation ( PVI ) using radiofrequency current ( RFC ) has become a st and ard treatment for drug-resistant and symptomatic paroxysmal AF ( PAF ) . In recent years , the cryoballoon-based technique is increasingly used as a promising alternative with a short learning curve . METHODS The FIRE AND ICE trial is a prospect i ve , r and omized , controlled , open , blinded outcome assessment , noninferiority trial comparing cryoballoon- , and RFC-based PVI .  Patients with drug-resistant PAF will be r and omized in a 1:1 matrix in multiple European centers . The primary hypothesis is that cryoballoon ablation is not inferior to RFC ablation using 3-dimensional mapping with respect to clinical efficacy . The primary endpoint is defined as the time to first documented clinical failure , including : ( 1 ) recurrence of AF ; ( 2 ) atrial flutter or atrial tachycardia ; ( 3 ) prescription of class I or III antiarrhythmic drugs ; or ( 4 ) re-ablation , whichever comes first , following a blanking period of 3 months after the index ablation procedure . The primary safety endpoint is a composite of death , stroke/transient ischemic attack , cardiac arrhythmias ( apart from AF recurrence ) causally related to the therapeutic intervention , and procedure-related serious adverse events . CONCLUSION The FIRE AND ICE trial compares 2 different technologies to perform catheter ablation of PAF with respect to efficacy and safety . It aims at providing objective data to guide selection and usage of ablation catheters in the treatment of AF 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 Introduction Pulmonary vein isolation ( PVI ) is an effective therapy for paroxysmal atrial fibrillation ( AF ) , but it has limitations . The two most significant recent advances have centred on the integration of real-time quantitative assessment of catheter contact force into focal radio frequency ( RF ) ablation catheters and the development of dedicated ablation tools capable of achieving PVI with a single ablation lesion ( A rct ic Front cryoballoon , Medtronic , Minneapolis , MN , USA ) . Although each of these holds promise for improving the clinical success of catheter ablation of AF , there has not been a rigorous comparison of these advanced ablation technologies . Moreover , the optimal duration of cryoablation ( freezing time ) has not been determined . Methods and analysis Patients undergoing an initial PVI procedure for paroxysmal AF will be recruited . Patients will be r and omised 1:1:1 between contact-force irrigated RF ablation , short duration cryoballoon ablation ( 2 min applications ) and st and ard duration cryoballoon ablation ( 4 min applications ) . The primary outcome is time to first documented AF recurrence on implantable loop recorder . With a sample size of 111 per group and a two-sided 0.025 significance level ( to account for the two main comparisons ) , the study will have 80 % power ( using a log-rank test ) to detect a difference of 20 % between contact force RF catheter ablation and either of the two cryoballoon ablation groups . Factoring in a 4 % loss to follow-up , 116 patients per group should be r and omised and followed for a year ( total study population of 348 ) . Ethics and dissemination The study was approved by the University of British Columbia Office of Research ( Services ) Ethics Clinical Research Ethics Board . Results of the study will be su bmi tted for publication in a peer- review ed journal . Trial registration number NCT01913522 ; Pre- 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 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 . ) 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 — 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 AIMS Catheter ablation of the pulmonary veins ( PVs ) is a promising therapeutic approach for symptomatic atrial fibrillation ( AF ) . The prospect i ve r and omized single-centre study ' Mesh Ablator versus Cryoballoon Pulmonary Vein Ablation of Symptomatic Paroxysmal Atrial Fibrillation ' ( MACPAF ; clinical trials.gov NCT01061931 ) compared the efficacy and safety of two balloon-based PV ablation systems . METHODS AND RESULTS Thirty-two patients underwent PV ablation for symptomatic paroxysmal AF using the A rct ic Front ® or the HD Mesh Ablator ® catheter  according to study protocol . The primary endpoint was complete PV isolation ( PVI ) at the end of the ablation procedure , determined by exit block after achieving entrance block . Long-term follow-up data are not included in this publication . Patients ' mean age was 61.7 ± 8.9 years , 43.2 % were female , and median CHA₂DS₂-VASc score was 2.0 . In the intention-to-treat analysis , the rate of the primary endpoint was 56.5 % in patients r and omized to the A rct ic Front ® and 9.5 % in patients r and omized to the HD Mesh Ablator ® catheter ( P = 0.001 ) . In the per- protocol analysis , complete PVI was achieved in 13 ( 76.5 % ) of 17 A rct ic Front ® patients but in none of the 15 HD Mesh Ablator ® patients ( P < 0.0001 ) . There were one major and two minor complications in each study arm but no clinical ly evident stroke . Post-procedural AF recurrence was detected within hospital stay in two ( 11.8 % ) A rct ic Front ® patients and in seven ( 46.7 % ) HD Mesh Ablator ® patients ( P = 0.049 ) . CONCLUSION The MACPAF study revealed a superiority of the A rct ic Front ® catheter concerning complete PVI . Owing to the insufficient efficacy of the HD Mesh Ablator ® catheter , the safety board decided to stop MACPAF prematurely 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 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 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
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
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 .