Left Atrial Posterior Wall Isolation Does Not Improve the Outcome of Circumferential Pulmonary Vein Ablation for Atrial Fibrillation

Abstract

Background-Ablation of the pulmonary veins (PVs) for atrial fibrillation treatment is often combined with linear radiofrequency lesions along the left atrium (LA) to improve the success rate. The study was designed to assess the contribution of LA posterior wall isolation to the outcome of circumferential pulmonary vein ablation (CPVA). Methods and Results-CPVA consisted of continuous radiofrequency lesions encircling both ipsilateral PVs plus an ablation line along the mitral isthmus. Patients were then randomized into 2 groups. In the first group, superior PVs were connected by linear lesions along the LA roof (CPVA-1 group). In the second group, the LA posterior wall was isolated by adding a second line connecting the inferior aspect of the 2 inferior PVs (CPVA-2 group). The study included 120 patients (53Ϯ11 years, 77% male, 60% paroxysmal atrial fibrillation, LA of 41.3Ϯ5.4 mm, 46% with hypertension, and 22% with structural heart disease). After a single ablation procedure and a mean follow-up of 10Ϯ4 months, 24 (40%) patients of the CPVA-1 group had atrial fibrillation recurrences and 3 (5%) had new-onset LA flutter. In the CPVA-2 group, recurrences were due to atrial fibrillation episodes in 23 patients (38%) and LA flutter in 4 (7%). Freedom from arrhythmia recurrences was not statistically different in the CPVA-1 group as compared with the CPVA-2 group (log rank Pϭ0.943). Conclusion-Isolation

Comparative Effectiveness of Wide Antral Versus Ostial Pulmonary Vein Isolation

“…These results suggest that antral ablation already targets the critical points of the LA posterior wall capable of triggering and sustaining arrhythmias and thus no further lesion lines are required. However, permanent isolation of the posterior wall was not proven in the study by Tamborero et al 47 In fact, all patients undergoing repeat procedures showed absence of posterior wall isolation and gaps along the box lesions.…”

“…A study performed by Tamborero et al, 47 which assessed the benefit of a box lesion in the LA posterior wall in patients undergoing transcatheter radiofrequency AF ablation, did not detect a better outcome of WACA PVI plus posterior box versus WACA PVI alone. These results suggest that antral ablation already targets the critical points of the LA posterior wall capable of triggering and sustaining arrhythmias and thus no further lesion lines are required.…”

2012 HRS/EHRA/ECAS Expert Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation: Recommendations for Patient Selection, Procedural Techniques, Patient Management and Follow-up, Definitions, Endpoints, and Research Trial Design

“…527 The recently published BELIEF trial reported at 28% efficacy of an extensive ablation strategy, including ablation of the posterior wall, in patients with long-standing persistent AF. 528,529 A survey of the writing group shows that 15% of the writing group members perform posterior wall isolation in patients with PAF during an initial AF ablation procedure, and 18% isolate the posterior wall during a repeat ablation procedure in a patient with PAF.…”

Atrial Fibrillation Catheter Ablation Versus Surgical Ablation Treatment (FAST)

“…Of note, part of these lines were made on an anatomic basis without verifying that conduction block had indeed been established. Whether additional lesions during either CA or SA would be beneficial for specific patient populations remains to be determined 24,25 ; this study was not designed or powered to answer that question.…”