Approach to ablative management of patient with persistent atrial fibrillation and enduring pulmonary vein isolation

Enduring isolation of the pulmonary veins (PV) is becoming increasingly common in patients undergoing repeat catheter ablation for atrial fibrillation. We describe our approach to ablation strategy in a patient with enduring isolation of PV and briefly discuss the role of non‐PV triggers.     

肺静脉电隔离术联合碎裂电位消融治疗持续性房颤疗效观察

目的：观察肺静脉电隔离术（ pulmonary vein isolation , PVI ）联合碎裂电位（ complex fractionated atrial electrograms , CFAE）消融对持续性房颤的疗效。方法对比观察23名于本院行房颤射频消融术的持续性房颤患者,所有患者均行PVI及左房顶部线性消融,其中12例联合CFAE消融,术后随访1年;观察两组手术时间、X线曝光时间、消融时间、手术并发症、左房大小、左房血栓、一次手术成功率等指标。结果联合CFAE消融组总手术时间（252±35） min、X线曝光时间（42±9．1）min、消融时间（94±11）min,单纯行PVI 组分别为（176±22）min、（34±7．6）min、（63±8）min,联合CFAE消融组手术各时间均明显延长（P＜0．01）;两组手术并发症、对左房大小及左房血栓的影响比较差异均无统计学意义;联合CFAE消融组一次手术成功率（75％）明显高于单纯行PVI组（64％）（ P＜0．05）。结论 PVI联合CFAE消融治疗持续性房颤虽增加手术、消融及X线曝光时间,但并不会提高并发症发生率,可提高房颤消融的一次手术成功率。     

Efficacy and safety of segmental ostial versus circumferential extra-ostial pulmonary vein isolation for atrial fibrillation

INTRODUCTION: Pulmonary vein (PV) isolation for atrial fibrillation (AF) can be performed using a segmental ostial or a circumferential extra-ostial approach. The relative merits and potential limitations of each approach are currently debated. Here we report our early experience with each of these approaches, including their relative efficacy and safety. METHODS AND RESULTS: Forty patients with drug-refractory AF underwent segmental ostial PV isolation and were compared to 40 consecutive patients who underwent PV isolation using a circumferential extra-ostial approach. The latter approach described here is novel in two aspects: (1) the endpoint for ablation was PV isolation and not only delay in left atrial to PV conduction time, and (2) isolation of the right and left PVs was achieved by a single encirclement of ipsilateral veins. At follow-up, 60% of the patients in the segmental group were free of AF compared to 75% of the patients in the circumferential group. There was one thromboembolic cerebrovascular complication during the ablation procedure in each group. CONCLUSION: PV isolation using a circumferential extra-ostial approach, where the ipsilateral PVs are isolated together by one encircling line of block using electroanatomic mapping, is a technically feasible procedure. This approach is at least as effective and safe as the more established segmental ostial approach for AF ablation.     

Our approach to persistent atrial fibrillation in the setting of pulmonary vein isolation

In patients with persistent atrial fibrillation (AF) despite durable pulmonary vein isolation, there are a variety of approaches to further ablation. Here we summarize our strategy in this population. In brief, our approach is to isolate the posterior wall, ablate the coronary sinus musculature and left lateral ridge, complete a lateral mitral line, and achieve cavotricuspid isthmus block. Subsequently, we target organized atrial flutters and if AF persists, we ablate areas of long, fractionated electrograms within scarred regions. We administer isuprel in patients with a presentation consistent with triggered atrial fibrillation (low scar burden, paroxysms of AF).     

心房颤动肺静脉电隔离术后早期复发的临床意义

目的:总结分析心房颤动(房颤)肺静脉电隔离术后早期(2周内)房颤复发者的随访结果.方法:105例房颤患者[平均年龄(55±12)岁],采用导管进行环肺静脉电隔离治疗,其中阵发性房颤78例,持续性房颤27例.实施环肺静脉电隔离共358根.结果:在术后早期随访[平均(3.9±2.6)d]中,105例患者中38例(36%)复发房颤.阵发性房颤与持续性房颤者早期房颤复发的发生率相比,差异无统计学意义(35%∶41%,P>0.05).在后期随访[平均(208±125)d]中,67例早期未复发患者中58例(87%)、38例早期房颤复发患者中13例(34%)无房颤发生,二者成功率比较,P<0.01.结论:肺静脉电隔离术后2周内大约36%患者房颤复发,早期房颤复发患者较早期未复发者后期成功率低.     

Percutaneous pulmonary vein isolation for treatment of atrial fibrillation

BACKGROUND: Transvenous catheter ablation for the treatment of atrial fibrillation is an evolving technique. AIM: The purpose of this study was to identify subgroups of patients most likely to benefit from pulmonary vein electrical isolation. METHODS: Patients with symptomatic atrial fibrillation resistant to pharmacological therapy were studied. Mapping-guided segmental application of radio-frequency energy was used to electrically isolate the pulmonary veins in 74 patients. Ischaemic or dilated cardiomyopathy was present in 34% of patients. Atrial fibrillation had been present for a mean time (+/- standard deviation) of 6.6 +/- 6.1 years. It was paroxysmal in 53 patients (72%). RESULTS: The mean number of procedures was 1.6/patient. After 6 +/- 6 months, 73% of patients (54/74) were in sinus rhythm. Thirteen of those in sinus rhythm were using anti-arrhythmic medications (25%). Recurrence of atrial fibrillation soon after pulmonary vein isolation occurred in 50%. Patients with persistent/permanent atrial fibrillation were less likely to be in sinus rhythm at follow up (11/21 (52%) vs 43/53 (81%); P = 0.01). However, the rate of early recurrence was similar in the intermittent and the persistent/permanent groups (26/53 (49%) vs 11/21(52%), respectively; P-value not significant). Patients with persistent atrial fibrillation were more likely to experience a recurrence of atrial fibril-lation (89%; P = 0.04). No other baseline factors predicted procedural success. Cardiac tamponade occurred in two patients and moderate pulmonary vein stenosis (>50% diameter narrowing) occurred in three patients. CONCLUSIONS: Pulmonary vein isolation is an effective curative treatment for a broad group of patients with atrial fibrillation. However, the procedure is only suitable for patients with problematic atrial fibrillation resistant to other therapies because of the small risk of serious complications.     

Impact of adenosine-provoked acute dormant pulmonary vein conduction on recurrence of atrial fibrillation

Impact of ATP Reconduction on AF Recurrence. Introduction: Adenosine can be associated with acute recovery of conduction to the pulmonary veins (PVs) immediately after isolation. The objective of this study was to evaluate whether the response to adenosine predicts atrial fibrillation (AF) recurrence after a single ablation procedure in patients with paroxysmal AF. Methods and Results: A total of 109 consecutive patients (61 ± 10 years; 91 males) with drug‐refractory paroxysmal AF who underwent AF ablation were analyzed. After PV antrum isolation (PVAI), dormant PV conduction was evaluated by an administration of adenosine in all patients. No acute reconnections were provoked by the adenosine in 70 (64.2%) patients (Group‐1), but they were provoked in at least one side of the ipsilateral PVs in 39 (35.8%) patients (Group‐2). All adenosine‐provoked dormant conductions were successfully eliminated by additional ablation applications. By 12 months after the initial procedure, 72 (66.1%) patients were free of AF recurrences without any antiarrhythmic drugs. A Cox regression multivariate analysis of the variables including the adenosine‐provoked reconductions, age, gender, duration of AF, presence of hypertension or structural heart disease, left atrial size, left ventricular ejection fraction, and body mass index demonstrated that adenosine‐provoked reconductions were an independent predictor of AF recurrence after a single ablation procedure (hazard ratio: 1.387; 95% confidence interval: 1.018–1.889, P = 0.038). At the repeat session for recurrent AF, conduction recovery was observed similarly in both groups (P = 0.27). Conclusion: Even after the elimination of any adenosine‐provoked dormant PV conduction, the appearance of acute adenosine‐provoked reconduction after the PVAI was an independent predictor of AF recurrence after a single AF ablation procedure. (J Cardiovasc Electrophysiol, Vol. 23 p. 256‐260, March 2012.)     

环肺静脉隔离术对阵发性心房颤动患者左心房大小和功能的影响

目的:探讨环肺静脉隔离术对阵发性心房颤动(Af)患者左心房大小和功能的影响。方法:28例阵发性Af患者择期行环肺静脉隔离术,根据Af复发与否分为复发组(5例)和未复发组(23例);同期选择窦性心律患者30例作为对照组。应用超声心动图对所有患者在窦性心律下于术前、术后24h、1个月和3个月时测量左心房最大容积(LAVmax)、左心房最小容积(LAVmin)、二尖瓣环晚期运动峰值速度(A峰)、肺静脉收缩期波(S峰)、舒张期波(D峰)、心房血流逆向波(PVa峰),并计算左心房射血分数(LAEF)。结果:①左心房大小:复发组和未复发组患者消融术前LAVmax和LAVmin均较对照组增加(均P<0.05),在术后24hLAVmin均增加(均P<0.01),LAVmax无明显变化;未复发组术后1个月时LAVmax、LAVmin均减小至正常(均P<0.05),术后3个月时未再进一步减小,而复发组术后1个月和3个月恢复至术前大小。②左心房功能:复发组和未复发组消融术前LAEF和A峰值均较对照组降低(均P<0.05),术后24h左心房功能指标均较术前明显降低(均P<0.05);术后1个月时复发组和未复发组左心房功能指标较术后24h均明显增加(均P<0.01),2组PVa峰、S峰和D峰值均恢复至术前正常水平(均P<0.05),LAEF和A峰在未复发组增加至正常水平(P<0.05),而在复发组仅恢复至术前水平;术后3个月时左心房功能指标较术后1个月时均未再有明显变化。结论:环肺静脉隔离术可以逆转阵发性Af造成的左心房大小和功能异常,而且长期对左心房大小和功能无负面影响。     

Impact of age on the outcome of pulmonary vein isolation for atrial fibrillation using circular mapping technique and cooled-tip ablation catheter:

INTRODUCTION: A retrospective analysis was performed to define the impact of age on the outcomes and complications in patients undergoing pulmonary vein isolation (PVI). PVI is an evolving technique for the management of atrial fibrillation (AF). The impact of age on the risks, outcomes, and complications of PVI has not been well defined. METHODS AND RESULTS: A total of 323 patients (259 men and 64 women; age 18-79 years) underwent PVI for treatment of drug-refractory symptomatic AF. An ostial isolation of the pulmonary veins was done using a cooled-tip ablation catheter guided by circular mapping. The patients were divided into three groups based on age (group I: <50 years, group II: 51-60 years, group III: >60 years) and the results were compared. There were 106 patients in group I, 114 patients in group II, and 103 patients in group III (mean age 41.3 +/- 7.8 years, 55.4 +/- 2.75 years, and 66.6 +/- 4.18 years, respectively) who underwent PVI for paroxysmal (53.8%), persistent (10.8%), or permanent (35.3%) AF. Baseline characteristics were similar except for a higher prevalence of hypertension and/or structural heart disease in groups II and III (58% and 63% vs 33% in group I, respectively). The procedural variables were similar in all age groups. The overall risk of complications was similar in the three groups, except that the risk of stroke was significantly higher in patients >60 years of age (3% vs 0%; P < 0.05). The recurrence rates of AF were similar in the three age groups (15.1%, 16.7%, and 18.4%, respectively; P > 0.05). The risk of severe pulmonary vein stenosis (1.8%, 2.6%, and 0.9%, respectively) was low and did not vary with age. CONCLUSION: PVI is a safe and effective treatment for patients with drug-refractory symptomatic AF, and its benefits extend to all age groups. The risk of procedural complications, especially thromboembolic events, appears to be higher in the elderly age group. This observation needs to be considered while assessing potential candidates for the procedure.     

Impact of pulmonary vein isolation on atrial vagal activity and atrial electrical remodeling

Objective Mechanisms of pulmonary vein isolation (PVI) for atrial fibrillation remain controversy.This study aimed to investigate the impact of PVI on vagal modulation to atria.Methods Eighteen adult mongrel dogs under general anesthesia were randomly divided into two groups.Bilateral cervical sympathovagal trunks were decentralized and sympathetic effects was blocked by metoprolol administration.Atrial electrical remodeling (AER) was established by rapid right atrial pacing at the rate of 600 bpm for 30 minutes.PVI was performed in group A.Atrial effective refractory period (ERP),vulnerability window (VW) of atrial fibrillation,and sinus rhythm cycle length (SCL) were measured at baseline and during vagal stimulation before and after atrial rapid pacing with and without PVI at fight atrial appendage (RAA),left atrial appendage (LAA),distal coronary sinus (CSd) and proximal coronary sinus (CSp).Results (1) Effects of PVI on vagal modulation:Shortening of SCL during vagal stimulation decreased significantly after PVI compared with that before PVI in group A (P＜0.001).Shortening of ERP during vagal stimulation decreaseed significantly after PVI compared with that before PVI (P＜0.05).VW of atrial fibrillation during vagal stimulation decreased significantly after PVI compared with that before PVI (P＜0.05).(2) Effects of PVI on AER:shortening of ERP before and after atrial rapid pacing increased significantly at baseline and vagal stimulation in group B compared with that in group A (P＜0.05).VW during vagal stimulation increased significantly after atrial rapid pacing in group B (P＜0.05).Conclusion PVI attenuates the vagal modulation to the atria,thereby decreases the susceptibility to atrial fibrillation mediated by vagal activity.PVI releases AER,which maybe contributes to the vagal denervation.Our study indicates that PVI not only can eradicate triggered foci but also modify substrates for AF.(J Geriatr Cardiol 2008;5:28-32)     

Substrate modification by pulmonary vein isolation and left atrial linear ablation in patients with persistent atrial fibrillation: its impact on complex-fractionated atrial electrograms

PV and Linear Ablation for CFAEs . Introduction: Linear ablations in the left atrium (LA), in addition to pulmonary vein (PV) isolation, have been demonstrated to be an effective ablation strategy in patients with persistent atrial fibrillation (PsAF). This study investigated the impact of LA linear ablation on the complex‐fractionated atrial electrograms (CFAEs) of PsAF patients. Methods and Results: A total of 40 consecutive PsAF patients (age: 54 ± 10 years, 39 males) who underwent catheter ablation were enrolled in this study. Linear ablation of both roofline between the right and left superior PVs and the mitral isthmus line joining from the mitral annulus to the left inferior PV were performed following PV isolation during AF. High‐density automated CFAE mapping was performed using the NAVX, and maps were obtained 3 times during the procedure (prior to ablation, after PV isolation, and after linear ablations) and were compared. PsAF was terminated by ablation in 13 of 40 patients. The mean total LA surface area and baseline CFAEs area were 120.8 ± 23.6 and 88.0 ± 23.5 cm² (74.2%), respectively. After PV isolation and linear ablations in the LA, the area of CFAEs area was reduced to 71.6 ± 22.6 cm² (58.7%) (P < 0.001) and 44.9 ± 23.0 cm² (39.2%) (P < 0.001), respectively. The LA linear ablations resulted in a significant reduction of the CFAEs area percentage in the region remote from ablation sites (from 56.3 ± 20.6 cm² (59.6%) to 40.4 ± 16.5 cm² (42.9%), P < 0.0001). Conclusion: Both PV isolation and LA linear ablations diminished the CFAEs in PsAF patients, suggesting substrate modification by PV and linear ablations. (J Cardiovasc Electrophysiol, Vol. 23, pp. 962‐970, September 2012)     

环肺静脉大环消融和肺静脉节段电隔离治疗阵发性心房颤动结果对比

目的 环肺静脉大环消融(CPVA)和肺静脉节段电隔离(SPVI)是目前导管射频消融治疗阵发性心房颤动(房颤)的两大主流术式,本文研究目的 是验证"CPVA对阵发性房颤的有效率比SP-VI高"这一假设,同时对比两种消融术式的其他治疗结果.方法 2006年1月至2007年12月入选阵发性房颤病人129例,SPVI和CPVA两组分别为64例和65例.排除标准为,房颤持续时间＞72 h,接受过导管消融的复发病例.结果 SPVI和CPVA组病人成功率分别为78.1%、78.5%;并发症发生率分别为7.8%、10.6%,差异无统计学意义.严重并发症3.9%.X线曝光时间SPVI组多于CPVA组,消融术时间CPVA组长于SPVI组.SPVI组的射频放电时间少于CPVA组.CPVA组术后房性心动过速/心房扑动发生率明显高于SPVI组(12.3%vs 3.1%).结论 SPVI和CPVA两种消融术式均能够比较安全有效地控制阵发性房颤的发作,治疗效果类似.