Cryoballoon Versus Radiofrequency for Pulmonary Vein Re‐Isolation After a Failed Initial Ablation Procedure in Patients with Paroxysmal Atrial Fibrillation

Cryoballoon versus Radiofrequency Ablation . 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 prospective randomized 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 randomized 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 randomized 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. (J Cardiovasc Electrophysiol, Vol. 24, pp. 274‐279, March 2013)     

Atrioesophageal Fistula Complicating Cryoballoon Pulmonary Vein Isolation for Paroxysmal Atrial Fibrillation

Although atrioesophageal fistula (AEF) formation is a well known, albeit rare, catastrophic complication of atrial fibrillation radiofrequency ablation procedures, there are less data regarding this complication using the cryoballoon technique. We report on 3 cases of AEF as a complication of cryoballoon pulmonary vein isolation at 3 different institutions with 2 different generations of cryoballoons.     

冷冻球囊消融与射频消融实现肺静脉隔离治疗阵发性心房颤动的比较

【】 目的 探讨阵发性心房颤动(AF)患者采用冷冻球囊消融( CBA) 与射频导管消融(RFCA)治疗效果的差异。 方法 回顾性分析2014年6月至2015年6月在华中科技大学附属协和医院接受导管消融治疗的AF患者的住院病历资料、手术记录和门诊随访资料,并进行对比。 结果 76例AF患者纳入研究,CBA组及RFCA组各38例。CBA组与RFCA组术中即时肺静脉隔离(PVI)成功率( 92% vs 96%) 和主要并发症发生率( 2.6% vs 10.53%) 均无明显差异。CBA组手术时间［(105.5±22.2)min vs (136±25) min,P＜0.01］、X线曝光时间［(19.3±6.0) min vs (22.4±5.2) min,P＜0.05］及消融时间［( 36.9±12.8) min vs(47±20.1) min,P＜0.05］均短于RFCA组。两组患者主要并发症的发生率均较低,其中CBA组的发生率为2.6%,RFCA的发生率为10.53%,二者的差异无统计学意义。随访结果显示,CBA组12个月的复发率为2.63%,RFCA组12个月的复发率为7.89%,二者的差异无统计学意义。 结论在AF患者的导管治疗中,CBA组和RFCA组具有相似的手术安全性及有效性。     

Cryoballoon Pulmonary Vein Isolation Supported by Intracardiac Echocardiography: Integration of a Nonfluoroscopic Imaging Technique in Atrial Fibrillation Ablation

Intracardiac Echo Supported Cryoballoon Ablation . Introduction: Cryoballoon ablation has been adopted for pulmonary vein (PV) isolation (PVI) in many centers. Complete occlusion of PV by an adequately sized balloon is crucial for effectiveness of cryoenergy delivery. The aim of this study was to evaluate intracardiac echocardiography (ICE) as an alternative imaging technique compared to angiographic imaging in cryoballoon PVI. Methods and Results: A total of 75 PVs were treated in 22 patients (61 ± 13 years, 17 male) undergoing PV cryoballoon ablation for drug refractory paroxysmal atrial fibrillation. Decision for an adequate balloon size was based on diameters of the PV antra assessed by ICE and PV angiography. Per PV 2.4 ± 0.4 cryoenergy pulses were applied. Decision for the balloon size was similar either based upon angiography or on ICE. A single 23 or 28 mm balloon was chosen in 10 and 3 patients, respectively. Two different sized balloons were used in 9 patients. PVI was evaluated after 2 cryoenergy applications. Total occlusion of the PV confirmed by ICE color flow Doppler (CFD) during ablation predicted successful PVI in 70 of 75 (93%) and unsuccessful PVI in 8 of 8 (100%). PV flow registered by pulsed wave Doppler at the PV ostium pre‐ and postablation was 0.48 ± 0.10 and 0.51 ± 0.12 m/s, respectively (n.s.). PVI was finally confirmed by entrance block in all PVs. No procedural complications occurred. Conclusions: ICE is a feasible novel imaging technique in cryoballoon ablation procedures. It allows decision for adequate balloon size, exact balloon placement, prediction of acute ablation success, and excludes acute narrowing of PV ostia. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1325‐1330, December 2010)