Results from a multicentre comparison of cryoballoon vs. radiofrequency ablation for paroxysmal atrial fibrillation: is cryoablation more reproducible? Cryoballoon vs. open irrigated radiofrequency ablation for paroxysmal atrial fibrillation: long-term FreezeAF outcomes 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 German ablation registry: Cryoballoon vs. radiofrequency ablation in paroxysmal atrial fibrillation--One-year outcome data. Comparison of cryoballoon and radiofrequency ablation of pulmonary veins in 40 patients with paroxysmal atrial fibrillation: a case-control study. Cryoballoon versus RF ablation in paroxysmal atrial fibrillation: results from the German Ablation Registry. Cryoballoon ablation of pulmonary veins for paroxysmal atrial fibrillation: first results of the North American Arctic Front (STOP AF) pivotal trial. Cryoballoon versus radiofrequency for pulmonary vein re-isolation after a failed initial ablation procedure in patients with paroxysmal atrial fibrillation. 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 Intraoperative radiofrequency ablation or cryoablation for hepatic malignancies. Long-term comparison of cryoballoon and radiofrequency ablation of paroxysmal atrial fibrillation: a propensity score matched analysis. Outcomes after cryoballoon or radiofrequency ablation for persistent atrial fibrillation: a multicentric propensity-score matched study Cryoballoon versus radiofrequency catheter ablation for paroxysmal atrial fibrillation. Multicenter randomized controlled trial of percutaneous cryoablation versus radiofrequency ablation in hepatocellular carcinoma. The effectiveness of a high output/short duration radiofrequency current application technique in segmental pulmonary vein isolation for atrial fibrillation. 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. Cryosurgical ablation and radiofrequency ablation for unresectable hepatic malignant neoplasms: a proposed algorithm.
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 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 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 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 INTRODUCTION Ablation of pulmonary veins ( PV ) is an established therapeutic option for patients with symptomatic drug-refractory paroxysmal atrial fibrillation ( AF ) .  Radiofrequency ( RF ) is currently the most widespread energy source for PV ablation . Cryothermal energy applied with a cryoballoon technique as an alternative has recently evolved . METHODS AND RESULTS In a case-control setting , we compared 20 patients with paroxysmal AF who underwent their first PV ablation with the cryoballoon technique to 20 matched patients with conventional RF ablation .  In the case of persistent electrical potentials after cryoballoon ablation , it was combined with ablation with a conventional cryocatheter . All patients performed daily event recording for 3 months after ablation procedure . Ablation parameters and success rate after 3 and 6 months were compared . In the cryoballoon group , the overall success rate was 55 % ( 50 % in the cryoballoon only group [ 14 patients ] and 66 % in the combination group [ 6 patients ] ) , as opposed to the RF group with 45 % . AF episode burden was lower after cryoballoon ablation . There was no significant difference between cryoballoon and RF ablation regarding procedure parameters . In the cryoballoon group , 3 phrenic nerve palsies occurred using the 23 mm balloon that resolved spontaneously . CONCLUSION PV ablation with the cryoballoon technique is feasible and seems to have a similar success rate in comparison to RF ablation . Procedure- and fluoroscopy duration are not longer than in conventional RF ablation BACKGROUND Catheter ablation is used extensively with curative intention in atrial fibrillation .  Radiofrequency ablation has long been a st and ard of care , while 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 therapy are lacking . METHODS Between January 2007 and August 2011 , a total of 3,775 consecutive patients with symptomatic paroxysmal AF who underwent PV ablation in their respective centers were enrolled . The cohort was divided into 2 groups according to the ablation energy source used : cryoballoon ablation ( group 1 , n = 905 [ 24.0 % ] , median age 63 years , 64.3 % men ) and RF ablation ( group 2 , n = 2870 [ 76.0 % ] , median age 63 years , 62.7 % men ) . Comorbidities and baseline clinical characteristics were similar in both groups . RESULTS Acute success rate was similar in both groups ( 97.5 % in cryo vs 97.6 % in RF ; P = 0.81 ) . Procedure times were similar , ablation and fluoroscopy times were higher in cryoballoon when compared to RF ablation .  Overall complication rate was similar in cryo- ( 4.6 % ) and RF-ablation ( 4.6 % ; P = 1.0 ) . Phrenic nerve palsy was more often in cryo versus RF ablation ( 2.1 % in cryo vs 0.0 % in RF ; P < 0.001 ) . Other complications were more common in RF compared to cryoablation ( 4.6 % in RF vs 2.7 % in cryo ; P < 0.05 ) . CONCLUSION RF ablation is the most widespread ablation method in Germany , but use of cryoballoon increased significantly . Procedure times were similar , but ablation and fluoroscopy times were longer in cryoballoon ablation . No significant differences were found in terms of acute success and overall complication rate 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 ) 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 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- BACKGROUND The majority of patients with primary or metastatic malignancies confined to the liver are not c and i date s for resection because of tumor size , location , multifocality , or inadequate functional hepatic reserve . Cryoablation has become a common treatment in select groups of these patients with unresectable liver tumors . However , hepatic cryoablation is associated with significant morbidity . Radiofrequency ablation ( RFA ) is a technique that destroys liver tumors in situ by localized application of heat to produce coagulative necrosis . In this study , we compared the complication and early local recurrence rates in patients with unresectable malignant liver tumors treated with either cryoablation or RFA . PATIENTS AND METHODS Patients with hepatic malignancies were entered into two consecutive prospect i ve , nonr and omized trials . The liver tumors were treated intraoperatively with cryoablation or RFA ; intraoperative ultrasonography was used to guide placement of cryoprobes or RFA needles . All patients were followed up postoperatively to assess complications , treatment response , and local recurrence of malignant disease . RESULTS Cryoablation was performed on 88 tumors in 54 patients , and RFA was used to treat 138 tumors in 92 patients . Treatment-related complications , including 1 postoperative death , occurred in 22 of the 54 patients treated with cryoablation ( 40.7 % complication rate ) . In contrast , there were no treatment-related deaths and only 3 complications after RFA ( 3.3 % complication rate , P<0.001 ) . With a median follow-up of 15 months in both patient groups , tumor has recurred in 3 of 138 lesions treated with RFA ( 2.2 % ) , versus 12 of 88 tumors treated with cryoablation ( 13.6 % , P<0.01 ) . CONCLUSIONS RFA is a safe , well-tolerated treatment for patients with unresectable hepatic malignancies . This study indicates that ( 1 ) complications occur much less frequently following RFA of liver tumors compared with cryoablation of liver tumors , and ( 2 ) early local tumor recurrence is infrequent following RFA 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 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 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 UNLABELLED Radiofrequency ablation ( RFA ) is considered a curative treatment option for hepatocellular carcinoma ( HCC ) . Growing data have demonstrated that cryoablation represents a safe and effective alternative therapy for HCC , but no r and omized controlled trial ( RCT ) has been reported to compare cryoablation with RFA in HCC treatment . The present study was a multicenter RCT aim ed to compare the outcomes of percutaneous cryoablation with RFA for the treatment of HCC . In all , 360 patients with Child-Pugh class A or B cirrhosis and one or two HCC lesions ≤ 4 cm , treatment-naïve , without metastasis were r and omly assigned to cryoablation ( n = 180 ) or RFA ( n = 180 ) . The primary endpoints were local tumor progression at 3 years after treatment and safety . Local tumor progression rates at 1 , 2 , and 3 years were 3 % , 7 % , and 7 % for cryoablation and 9 % , 11 % , and 11 % for RFA , respectively ( P = 0.043 ) . For lesions > 3 cm in diameter , the local tumor progression rate was significantly lower in the cryoablation group versus the RFA group ( 7.7 % versus 18.2 % , P = 0.041 ) . The 1- , 3- , and 5-year overall survival rates were 97 % , 67 % , and 40 % for cryoablation and 97 % , 66 % , and 38 % for RFA , respectively ( P = 0.747 ) . The 1- , 3- , and 5-year tumor-free survival rates were 89 % , 54 % , and 35 % in the cryoablation group and 84 % , 50 % , and 34 % in the RFA group , respectively ( P = 0.628 ) . Multivariate analyses demonstrated that Child-Pugh class B and distant intrahepatic recurrence were significant negative predictors for overall survival . Major complications occurred in seven patients ( 3.9 % ) following cryoablation and in six patients ( 3.3 % ) following RFA ( P = 0.776 ) . CONCLUSION Cryoablation result ed in a significantly lower local tumor progression  than RFA , although both cryoablation and RFA were equally safe and effective , with similar 5-year survival rates 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 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 Thermal ablation of unresectable hepatic tumors can be achieved by cryosurgical ablation ( CSA ) or radiofrequency ablation ( RFA ) . The relative advantages and disadvantages of each technique have not yet been determined . HYPOTHESIS Radiofrequency ablation of malignant hepatic neoplasms can be performed safely , but is currently limited by size . Cryosurgical ablation , while associated with higher morbidity , is more effective for larger unresectable hepatic malignant neoplasms . DESIGN Retrospective analysis of prospect i ve patient data base . PATIENTS AND METHODS Between July 1992 and September 1999 , 308 patients with liver tumors not amenable to curative surgical resection were treated with CSA and /or RFA ( percutaneous , laparoscopic , celiotomy ) . No patient had preoperative evidence of extrahepatic disease . All patients underwent laparoscopy with intraoperative ultrasound if technically possible . Both RFA and CSA were performed under ultrasound guidance . Resection , as an adjunctive procedure , was combined with ablation in certain patients . RESULTS Laparoscopy identified extrahepatic disease in 12 % of patients , and intraoperative hepatic ultrasound identified additional lesions in 33 % of patients , despite extensive preoperative imaging . Radiofrequency ablation alone or combined with resection or CSA result ed in reduced blood loss ( P<.05 ) , thrombocytopenia ( P<.05 ) , and shorter hospital stay compared with CSA alone ( P<.05 ) . Median ablation times for lesions greater than 3 cm were 60 minutes with RFA and 15 minutes with CSA ( P<.001 ) . Local recurrence rates for lesions greater than 3 cm were also greater with RFA ( 38 % vs 17 % ) . CONCLUSIONS Laparoscopy and intraoperative ultrasound are essential in staging patients with hepatic malignant neoplasms . Radiofrequency ablation when combined with CSA reduces the morbidity of multiple freezes . Although RFA is safer than CSA and can be performed via different approaches ( percutaneously , laparoscopically , or at celiotomy ) , it is limited by tumor size ( <3 cm ) . Percutaneous RFA should be considered in high-risk patients or those with small local recurrences
Conclusions Compared with RF ablation , cryoablation present a comparable long-term AF/atrial tachycardial-free survival and procedure-related adverse events .
Meanwhile , cryoablation markedly shorten the procedure time , nonetheless , with negligible impact on the fluoroscopy time
Aims Cryoablation is a promising alternative technique to RF ablation for treating paroxysmal AF with encouraging results .
However , data about the efficacy and safety comparison between cryoablation and RF ablation is still lacking .