Cryoballoon ablation versus radiofrequency ablation for atrial fibrillation

Catheter ablation (CA) provides the most effective treatment option for patients suffering from symptomatic atrial fibrillation (AF). The procedural cornerstone of all ablation strategies and for all entities of AF is the electrical isolation of the pulmonary veins (PV). CA with the use of radiofrequency (RF) in conjunction with a 3-dimensional electroanatomical mapping system is the most established ablation approach, but it demands a long learning curve and recurrences of AF are commonly the result of recovered PV conduction. As a consequence, novel ablation systems such as the Cryoballoon (CB) have been evolved aiming at facilitation and increased efficacy of pulmonary vein isolation (PVI). CB ablation is characterized by a short learning curve as well as short procedure times and demonstrated non-inferiority with regard to safety and efficacy when being directly compared to RF ablation for treatment of paroxysmal AF. However, RF ablation is first choice for treatment of persistent AF, in particular when expanded ablation strategies beyond PVI are intended in order to improve clinical outcomes.     

微创射频消融治疗心房颤动

心房颤动（简称房颤）是最常见的快速型心律失常之一,可增加心血管疾病死亡率和发病率,我国流行病学研究显示房颤发病率为0.73％[1].房颤治疗原则包括：控制心室率、抗凝治疗、缓解症状、治疗基础心脏病和诱发因素、恢复并维持窦性心律.房颤的药物疗效差,不能预防血栓栓塞和心力衰竭,抗凝药物的应用虽然减少血栓栓塞风险但同时也增加了出血风险.导管及外科的射频消融治疗房颤效果明显好于单纯药物治疗12-4].内、外科微创射频消融治疗房颤各有优缺点,可结合其优点联合治疗房颤.     

房颤治疗:外科射频消融术与内科导管射频消融术孰优?

诸学时:2006年10月13日,中国第一家房颤研究治疗中心——北京安贞医院房颤中心,在北京召开的第四届五洲国际心血管病研讨会上正式宣告成立。该中心集医疗、科研、教学、培训和咨询五位一体,整合了安贞医院心脏内科和外科两支房颤研究治疗团队的力量,优势互补。其学科带头人均是我国著名心脏病学专家。心脏内科马长生教授于1998年率先在国内开展房颤的经导管射频消融治疗,截至目前已累计完成近千例,为国内最大系列。在心脏外科孟旭教授带领下,2002年安贞医院开始外科直视下的房颤射频消融术,至今累计完成420例,为国内最大系列,也是亚洲范围内…     

Intra-operative cooled-tip radiofrequency linear atrial ablation to treat permanent atrial fibrillation.

AIMS: To demonstrate the safety and efficacy of saline irrigated cooled-tip atrial linear endocardial radiofrequency ablation (SICTRA) concomitant to open-heart surgical procedures in the treatment of permanent atrial fibrillation (AF). METHODS AND RESULTS: Two hundred and twenty-two patients presenting with permanent AF and the need for cardiac surgery were included. In addition to the cardio-surgical procedure [mitral valve (MV) surgery (n = 94), aortic valve replacement (n = 29), bypass surgery (n = 76 including 24 patients with additional MV surgery), and combined procedures (n = 23)] concomitant SICTRA was performed. In 116 patients, the ablation pattern was restricted to the left atrium alone. During the mean follow-up of 29 months, 174 patients (78%) converted to sinusrhythm (SR). In patients with SICTRA restricted to the left atrium conversion rates were not different compared to a biatrial approach (83 vs. 74%, P = 0.47). Thirty-days mortality was found to be 4% (9/222). Post-mortem evaluation revealed 23% of all lesions to be histologically non-transmural. In the overall group, only 4% of patients developed sustained secondary regular atrial arrhythmia. CONCLUSIONS: SICTRA safely and effectively restores stable SR in 78% of patients with permanent AF undergoing open-heart surgery. Rhythm outcome is not influenced by treatment of the right atrium. Sustained regular atrial arrhythmia with the need for invasive treatment strategies occurs in 4% although intra-operative ablation lesions are often non-transmural.     

Effect of atrial radiofrequency ablation designed to cure atrial fibrillation on atrial mechanical function

INTRODUCTION: The effects of linear radiofrequency lesions in the atria for cure of atrial fibrillation on atrial contraction have not previously been quantified. METHODS AND RESULTS: Atrial function was measured before and 30 +/- 24 days after a biatrial ablation procedure designed to cure atrial fibrillation in eight dogs and after a sham procedure in three dogs. Atrial mechanical function was assessed using Doppler diastolic blood flow velocities, atrial systolic pressure wave amplitude, and assessment of atrial contribution to cardiac output estimated by comparison of AV sequential pacing to ventricular pacing at the same heart rate. The mitral Doppler A/E velocity ratio was 1.03 +/- 0.45 before and 0.72 +/- 0.43 after ablation (P = 0.048). The tricuspid A/E ratio was 0.88 +/- 0.17 before and 0.71 +/- 0.12 after ablation (P = 0.04). The estimated atrial contribution to cardiac output was 18% +/- 9% before and 5% +/- 4% after ablation (P < 0.01). The left atrial systolic pressure wave amplitude was 2.8 +/- 1.5 mmHg before and 1.7 +/- 1.0 mmHg after ablation (P = 0.1). These changes were not observed in control dogs. Lesions covered 25% +/- 6% of the atrial endocardial surface. CONCLUSION: Multiple linear radiofrequency lesions in the atria designed to cure atrial fibrillation may impair atrial contractility. Reduced atrial function is partly due to loss of atrial myocardial mass, but regional delays in atrial activation and splinting of the atria by scarring also may contribute.     

Acute effects of left atrial radiofrequency ablation on atrial fibrillation

INTRODUCTION: Acutely, when left atrial ablation is performed during atrial fibrillation (AF), the AF may persist and require cardioversion, or it may convert to sinus rhythm or to atrial tachycardia/flutter. The prevalence of these acute outcomes has not been described. METHODS AND RESULTS: Left atrial ablation, usually including encirclement of the pulmonary veins, was performed during AF in 144 patients with drug-refractory AF. Conversion to sinus rhythm occurred in 19 patients (13%), to left atrial tachycardia in 6 (4%), and to atrial flutter in 6 (4%). In the 6 patients with a focal atrial tachycardia, the mean cycle length was 294 +/- 45 ms. The tachycardia arose in the left atrial roof in 3 patients, the left atrial appendage in 2, and the anterior left atrium in 1. In 3 of 6 patients, the focal atrial tachycardia originated in an area that displayed a relatively short cycle length during AF. In 6 patients, AF converted to macroreentrant atrial flutter with a mean cycle length of 253 +/- 47 ms, involving the mitral isthmus in 5 patients and the septum in 1 patient. All atrial tachycardias and flutters were successfully ablated with 1 to 15 applications of radiofrequency energy. CONCLUSION: When left atrial ablation is performed during AF, the AF may convert to atrial tachycardia or flutter in approximately 10% of patients. Focal atrial tachycardias that occur during ablation of AF may be attributable to driving mechanisms that persist after AF has been eliminated, whereas atrial flutter results from incomplete ablation lines.     

胸腔镜辅助下双极射频消融治疗房颤

目的 探讨微创双极射频消融对房颤治疗的效果.方法 10例阵发性房颤患者,房颤时间均在1年以上,平均年龄53岁,尢器质性心脏病,心肺肝肾功能正常,气管插管麻醉,非体外循环胸腔镜辅助下双极射频先行右肺静脉环状消融,然后行左肺静脉环状消融,最后切割缝合器切除左心耳.结果 全组无死亡,术后随访1至3个月.房颤转复率90%.复发1例,为房颤6年的患者.结论 微创双极射频消融是一种操作简单、安全有效的外科治疗房颤方法.     

Ventricular fibrillation secondary to radiofrequency application in ventricular tachycardia ablation

Radiofrequency catheter ablation has become a first line therapy for several types of tachycardias because of its high efficacy and low complication rate. The development of proarrhythmic complications due to a direct effect of radiofrequency is very unusual. We describe a patient with previous myocardial infarction and well tolerated sustained monomorphic ventricular tachycardia who underwent catheter ablation of the tachycardia substrate. During two of the radiofrequency applications, ventricular fibrillation developed and external defibrillation was required.     

Endoscopic management of an esophagopericardial fistula after radiofrequency ablation for atrial fibrillation

A case is reported of a 76-year-old man with a past history of atrial fibrillation. A radiofrequency ablation procedure was suggested following several failed cardioversion attempts. However, an esophagopericardial fistula complicated the procedure. This life-threatening complication was successfully managed using both the placement of a covered esophageal stent and surgical pericardial and mediastinal drainage. In fact, no persisting fistula could be detected when the esophageal stent was removed seven weeks later. Atrioesophageal and esophagopericardial fistulas are two of the most severe complications associated with cardiological radiofrequency ablation procedures. They are responsible for majority of the deaths associated with this procedure. Despite the extremely high morbimortality associated with cardiothoracic surgery in such conditions, this treatment is the gold-standard for the management of such complications. This case report emphasizes the importance and efficacy of the endoscopic approach as part of a multidisciplinary management approach to this serious adverse event following radiofrequency ablation for atrial fibrillation.     

Percutaneous radiofrequency catheter ablation for atrial fibrillation prior to atrial septal defect closure

Percutaneous Radiofrequency Catheter Ablation. Patients with an atrial septal defect (ASD) commonly have atrial fibrillation (AF) and closure of the ASD rarely controls the arrhythmia. We report on the management of 4 patients with recurrent medically refractory AF in the setting of an unrepaired ASD who underwent percutaneous RFA prior to ASD closure. In 3 of the 4 patients AF was controlled after ablation without antiarrhythmic drug therapy and in the fourth patient AF was controlled with antiarrhythmic therapy after ASD closure. Based on these limited results it seems reasonable to consider RFA of medically refractory AF in patients prior to planned percutaneous ASD closure.     

Left atrial flutter after radiofrequency catheter ablation of focal atrial fibrillation

We report an arrhythmic complication in two patients in whom a procedure directed at isolating one or two pulmonary veins had been performed. The complication was related to pulmonary vein disconnection scars after ablation. Both patients developed new clinical tachycardia (atypical atrial flutter) secondary to a reentrant phenomena in the vicinity of a previously ablated pulmonary vein.     

应用完全胸腔镜射频消融技术治疗心房颤动的初步结果

微创外科射频消融治疗心房颤动（房颤）是当今心血管外科领域倍受关注的热点之一。我院在采用双侧胸部小切口和胸腔镜辅助下双侧肺静脉射频消融隔离术的基础上,自2010年4月至2011年3月在国内率先开展了完全电视胸腔镜下双侧肺静脉射频消融并左心耳切除术治疗单纯性房颤,现对其技术方法和9例随访结果报道如下。     

Cost analysis of radiofrequency catheter ablation for atrial fibrillation

Atrial fibrillation is the most common arrhythmia associated with increased mortality and morbidity. Its management requires high healthcare expenditures; 52%–70% of expenses for AF care are constituted by hospitalization costs. The current management strategies of pharmacological rhythm control and pharmacological or invasive rate control show no difference in impact on major outcomes in patients with AF. Radiofrequency catheter ablation (RFA) has been shown to reduce the risk of AF recurrence, improve quality of life and reduce hospitalization rate as compared to pharmacological rhythm control and rate control strategies. This review summarizes current knowledge on cost and cost-effectiveness analysis of RFA for patients with atrial fibrillation.     

心脏直视手术同期双极射频消融迷宫术治疗心房颤动

目的:探讨心内直视下同期双极射频消融治疗器质性心脏病合并心房颤动的经验及疗效.方法:2008年12月至2010年2月间采用Cardioblate<,TM>冲洗式双极射频消融机为21例器质性心脏病(19例为风湿性瓣膜病、2例为先天性心脏病)合并心房颤动患者施行消融术,其中持续性/永久性房颤17例,阵发性房颤4例,消融经线...     

Esophageal temperature monitoring during radiofrequency ablation of atrial fibrillation

INTRODUCTION: Ablative strategies for atrial fibrillation have centered on the left atrium, in particular the pulmonary veins. An emphasis on ablating outside the ostia of the pulmonary veins appears to have reduced the risk of pulmonary vein stenosis. Unfortunately, ablation in the posterior left atrium has been reported to result in fatal atrio-esophageal fistula. METHODS AND RESULTS: We monitored esophageal temperatures in 16 consecutive patients undergoing atrial fibrillation ablation. There were 14 men and 2 women; average age 54.7 +/- 10.6 years. Eight patients had a lasso-guided pulmonary isolation procedure, eight an electroanatomically guided left-atrial circumferential approach. A commercially available esophageal temperature probe (Mallinckrodt Mon-a-therm 12F Esophageal Stethoscope with Temperature Sensor, Thermistor 400 Series) was positioned under general anesthesia. Temperature changes were noted and related to the relative location of the ablation catheter and the temperature probe during the temperature change. The esophagus was midline in three, right sided in three, and left sided in the remaining patients. Temperature rises could be recorded at the posterior aspect of any pulmonary vein. Detailed analysis of six patient maps revealed heating occurred with lesions created within 1 cm of the esophagus. CONCLUSION: The location of the esophagus relative to the back of the left atrium displays considerable variability. It is rarely midline and most often lies in close proximity to the left-sided veins. Ablation in close radiographic proximity (approximately 1 cm) to the esophagus as defined by a radio-opaque temperature probe can result in heating at the esophageal lumen.