Circumferential ablation with pulmonary vein isolation in permanent atrial fibrillation

Each of the main approaches to catheter ablation of atrial fibrillation (AF, segmental and circumferential) is associated with limited efficacy in patients with permanent AF. The objective is to report outcomes of circumferential ablation with pulmonary vein (PV) isolation, determined using a circular mapping catheter, in patients with permanent AF and determine relations between the duration of permanent AF and efficacy. The patient population was composed of 41 consecutive patients (34 men; age 58 +/- 11 years) with permanent AF who underwent radiofrequency catheter ablation through circumferential ablation with PV isolation. They were in permanent AF for 2.3 +/- 3.6 years, and 3.4 +/- 2.2 cardioversion procedures and 1.9 +/- 0.8 class I/III antiarrhythmic drugs had failed. After a follow-up of 11 +/- 2 months, the single-procedure success rate was 36% (n = 15) with an additional 12% (n = 5) showing improvement. With repeat procedures in 19%, the success rate was 54% (n = 22) with an additional 12% (n = 5) showing improvement. All patients who underwent repeat ablations had recovered PV conduction. Single-procedure success was higher in patients who were in permanent AF for < or =1 year compared with those in permanent AF for >1 year (50% vs 20%, respectively, p = 0.05). A major complication occurred in 4 patients (8%), including 3 patients with vascular complications and 1 with stroke. In conclusion, study results suggest that circumferential ablation with PV isolation has moderate efficacy in patients with permanent AF. Efficacy is limited in those in continuous AF for >12 months.     

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)     

对射频消融术后心房颤动复发患者在三维标测系统指导下再次手术治疗

目的探讨射频消融术后心房颤动(房颤)复发的原因及再次手术对房颤的影响。方法入选随访3个月以上自觉症状较术前无好转、心电图证实仍有房颤发作的患者,于三维标测系统指导下行电生理研究及环肺静脉线性消融术,手术终点为环肺静脉消融线的完整及肺静脉的彻底电学隔离。所有患者再次手术后随访至少4个月,观察再次射频消融治疗对复发房性心律失常的影响。结果总计23例复发患者在2005年2月以前入院接受再次手术治疗,占同期复发患者的51.1%(2345)。其中13例首次手术时消融策略为节段性肺静脉消融(SPVA),另外10例为环肺静脉线性消融(CPVA),慢性持续性房颤患者占56.5%(1323)。首次手术为节段性肺静脉消融者肺静脉左心房电传导恢复率(以每根肺静脉为单位计算)为92.3%(4852),而首次接受环肺静脉线性消融术者肺静脉左心房电传导恢复率(以每根肺静脉计算)为75.0%(3040)。手术中见首次接受节段性肺静脉消融术的患者再次手术的手术时间、X线时间及放电时间均较长,与首次接受环肺静脉线性消融术的患者相比差异具有统计学意义。再次手术后平均随访4.2±3.5(4.0～9.0)个月,累计无房性快速心律失常率为82.6%(1923)。结论肺静脉左心房电传导恢复是多数房颤患者复发的原因;三维标测系统指导下的环肺静脉线性消融术用于治疗复发患者同样安全有效。     

Phased-array intracardiac echocardiography during pulmonary vein isolation and linear ablation for atrial fibrillation

INTRODUCTION: Fluoroscopic imaging provides limited anatomic guidance for left atrial structures. The aim of this study was to determine the utility of real-time, phased-array intracardiac echocardiography during radiofrequency ablation for atrial fibrillation. METHODS AND RESULTS: In 29 patients undergoing pulmonary vein isolation (n = 16) or linear (n = 13) left atrial radiofrequency ablation for atrial fibrillation, intracardiac phased-array echocardiography was used to visualize left atrial anatomy and the pulmonary veins, as well as ablation and mapping catheters during ablation procedures. In the 16 pulmonary vein isolation patients, the mean pulmonary vein ostial diameters measured by venography and intracardiac echocardiography were similar for all veins positions, except that left common pulmonary vein diameters were larger as measured by echocardiography (2.50 +/- 0.29 cm) than by venography (1.79 +/- 0.50 cm, P = 0.001). The ostial diameters measured by echocardiography and venography were not correlated, however (r = 0.23, P = 0.19). As directed by echocardiography, only 1 of 25 circular mapping catheters (4%) used in 16 patients was replaced due to inappropriate sizing of the pulmonary veins. Mean pulmonary vein Doppler flow velocities increased after ablation for left-sided veins but ostial diameters were unchanged. In the linear ablation patients, the entire extent of the linear electrode array could be visualized in only 3 of 52 of catheter positions (6%) in the 13 patients. A portion of the catheter could be seen in only 50% of all target catheter positions. CONCLUSION: Phased-array intracardiac echocardiography (1) allows sizing and positioning of pulmonary vein mapping catheters, (2) provides measures of pulmonary vein ostial diameters, (3) continuously monitors pulmonary vein Doppler flow velocities, and (4) has limited use in positioning linear ablation catheters in the left atrium.     

Pulmonary vein isolation and linear lesions in atrial fibrillation ablation

Background Various strategies have been used for atrial fibrillation (AF) ablation. It is unclear whether adding linear lesions to pulmonary vein (PV) isolation has significant advantages. Objectives We assessed the clinical benefit of adding linear lesions in patients undergoing PV isolation for AF. Methods One hundred patients (63 male and 37 female; mean age of 59 ± 11 years) with documented paroxysmal AF were included in the study. Patients were randomized into two groups. The first group underwent PV isolation alone. The second group underwent PV isolation and had two linear lesions created; one line between the superior PVs, and a second line from the left inferior PV to the mitral valve annulus. Patients’ clinical progress after the ablation was evaluated and compared at 1, 3, and 9 months after their respective ablation procedures. Results The linear lesions group maintained sinus rhythm and had fewer symptoms than the lone PV isolation group (86 vs. 58%, respectively) (p < 0.05) at 1 month. At 9 months, when patients who reverted to AF underwent additional management to regain sinus rhythm (90 vs. 82%, respectively) (p = NS), there was no statistical difference between the groups regarding the use of antiarrhythmics, the need for electrical cardioversion, and subjective improvement. Conclusion The addition of linear lesions to PV isolation more effectively achieved sinus rhythm initially and fewer patients required additional management to maintain their rhythm when compared to patients who underwent lone PV isolation. However, at 9 months, the overall results were similar in both groups.     

肺静脉电隔离治疗左心房线性消融后复发的心房颤动--肺静脉电隔离的必要性

自90年代后期射频导管消融治疗心房颤动(房颤)应用于临床以来，对房颤的发生机制的认识及治疗方法有了越来越多的研究与报道。目前尚无充分的证据支持以任何一种方法完全取代另外一种，在不同的中心采用的方法亦不统一。以下结合1例肺静脉电隔离成功治疗左心房线性消融后复发的阵发性房颤，以阐明肺静脉电隔离的必要性。     

Fractal complexity alternations in paroxysmal atrial fibrillation patients with and without recurrence after pulmonary vein isolation

Background

Pulmonary vein isolation (PVI) is a cornerstone therapy for paroxysmal atrial fibrillation (PAF). The variations in nonlinear heart rate variability (HRV) between patients with and without recurrences remain unclear. We aimed to characterize the nonlinear HRV before and after PVI in patients with and without recurrence.

Methods

Twenty-five drug-refractory PAF patients (56.0 ± 9.1 years old, 20 males) who received PVI were enrolled. Holter electrocardiography were performed before, 1–3, and 6–12 months after PVI. After 8.2 ± 2.5 months of follow-ups after PVI, patients were divided into two groups: the recurrence (n = 8) and non-recurrence (n = 17) groups. Linear and nonlinear HRV variables were analyzed, including the Poincaré Plot analysis and the Detrended Fluctuation Analysis (DFA).

Results

The non-recurrence group, but not the recurrence group, had decreased high-frequency component (HF), the root mean square of successive RR interval differences (RMSSD), and the Poincaré Plot index SD1 1–3 months after PVI and increased DFA_slope2 6–12 months after PVI. The non-recurrence group's LF/HF ratio and DFA_slope1 decreased significantly 1–3 and 6–12 months after PVI, respectively, whereas there was no significant change in the recurrence group after PVI.

Conclusions

Significantly reduced vagal tone 1–3 months after PVI, increased long-term fractal complexity 6–12 months after PVI, and decreased sympathetic tone as well as short-term fractal complexity 1–3 and 6–12 months after PVI led to a better AF-free survival after PVI. These findings suggest that neuromodulation and heart rate dynamics play crucial roles in AF recurrence following PVI.     

阵发性心房颤动射频导管消融术后生活质量随访

目的　探讨经导管射频消融治疗阵发性心房颤动 (房颤 )的安全性、有效性以及对生活质量的影响。方法　 30例药物难治性阵发性房颤 ,在环状电极导管 (Lasso导管 )指导标测下行肺静脉或上腔静脉电隔离 ,术后随访并行隔离术前后生活质量调查。结果　有 2 9例达消融终点 ,随访 1～ 2 6个月 ,17例消融成功 ,无需药物可以维持窦性心律 ,加用以前无效的抗心律失常药物后 ,有 2 2例无房颤复发。生活质量(QOL)调查示隔离术前后相比 ,SF 36量表中除肌体疼痛差异无显著性外 ,其它 7项指标 :躯体功能、躯体角色、总的健康状况、活力、社会功能、情感角色和心理健康 ,术后均有改善 (P <0 0 5 ) ;而症状列表中除胸痛外 ,心悸、心动过速、呼吸困难、头昏、活动受限 ,术后均有改善 (P <0 0 5 )。结论　部分药物难治性房颤患者可行射频导管消融肺静脉电隔离治疗 ,成功地消除房颤可明显提高患者的QOL且改善症状。     

环肺静脉线性消融电学隔离肺静脉治疗100例心房颤动临床评价

目的探讨三维标测系统和单环状标测电极指导下行环肺静脉线性消融电学隔离肺静脉治疗心房颤动(房颤)的可行性和有效性。方法自2004年4月至2005年1月共对连续100例症状明显、发作频繁、抗心律失常药物治疗无效的房颤患者进行了在CARTO系统(76例)或EnSite-NavX系统(24例)指导下的环肺静脉线性消融术,消融终点为双侧肺静脉的彻底电学隔离。结果100例患者共完成200个环形消融环,肺静脉电学隔离率为95.0%。操作时间150～365(240±65)min,X线时间为23～61(37±12)min。其中8例(8.0%)复发患者接受了再次导管消融。随访5.5～12(10.2±5.7)个月,累计无房性快速心律失常率为85.0%。术后1、2、3、4、5、6个月时无房性快速心律失常率分别为66.0%、82.0%、87.0%、85.0%、85.0%、88.6%。并发症包括1例心脏压塞,经保守治疗后康复,1例患者出现无症状性肺静脉狭窄。结论在三维标测系统指导下,环肺静脉线性消融电学隔离肺静脉治疗房颤安全有效。     

Mechanisms of recurrent atrial fibrillation after pulmonary vein isolation by segmental ostial ablation

OBJECTIVES: The aim of this study was to determine the mechanisms responsible for recurrent atrial fibrillation (AF) after pulmonary vein isolation (PV) by segmental ostial ablation. BACKGROUND: Recovery of conduction into a previously isolated PV is a common observation when there is recurrent AF soon after segmental ostial ablation. However, the mechanisms of recurrent AF have been unclear. METHODS: A repeat ablation procedure was performed in 50 patients who had recurrent paroxysmal AF at a mean of 7 +/- 6 months after segmental ostial ablation to isolate the PVs. During the repeat procedure, a ring catheter was inserted into each PV during sinus rhythm and AF to determine whether the veins were still isolated and, if not, whether there were PV tachycardias with a cycle length shorter than in the adjacent left atrium during AF. RESULTS: There was recovery of conduction over a previously ablated muscle fascicle in >/=1 PV in 49 patients (98%). There were 10 +/- 2 episodes of PV tachycardia per minute in 36 (72%) of the 50 patients during AF. Repeat ablation was performed by segmental ostial ablation (23 patients) or by left atrial catheter ablation to encircle the left- and right-sided PVs 1 to 2 cm from the ostia, with additional ablation lines in the posterior left atrium and mitral isthmus (27 patients). At 6-month follow-up, among 23 patients who underwent repeat ablation by segmental ostial ablation, AF recurred in 4 (21%) of the 19 patients who had PV tachycardias and in 3 (75%) of the 4 patients who did not (P = .03). Among the 27 patients who underwent left atrial ablation, AF recurred in 2 (12%) of the 17 patients who had PV tachycardias and in 1 (10%) of the 10 patients who did not (P = 0.7). CONCLUSIONS: Recovery of conduction in previously ablated muscle fascicles is a common finding in patients with recurrent AF after segmental ostial ablation. The efficacy of repeat segmental ostial ablation depends on the presence of PV tachycardias, whereas left atrial ablation is effective regardless of whether PV tachycardias are present or not during AF.