Cryoballoon Pulmonary Vein Isolation With Versus Without Additional Right Atrial Linear Ablation for Persistent Atrial Fibrillation: The CRALAL Randomized Clinical Trial

Abstract

Background: Pulmonary vein isolation (PVI) alone is less effective in patients with persistent atrial fibrillation (AF) compared with those with paroxysmal AF. We investigate whether additional linear ablation from the superior vena cava to the right atrial septum and cavotricuspid isthmus ablation improves the rhythm outcome of patients with persistent AF undergoing cryoballoon PVI (Cryo-PVI).

Methods: In this investigator-initiated, multicenter, randomized clinical trial, 289 patients with persistent AF refractory to antiarrhythmic drug therapy were randomized 1:1 to either Cryo-PVI with additional right atrium (RA) linear ablation or Cryo-PVI alone. The primary end point was any documented atrial arrhythmia lasting ≥30 seconds after a 3-month blanking period after ablation. The secondary end points were atrial arrhythmia recurrence or antiarrhythmic drug use after a 3-month blanking period, complications, and total procedure time.

Results: During the median follow-up of 24 months (median age, 63 years; 23.9% women), the atrial arrhythmia recurrence was less frequent in the additional RA ablation group (n=50, 37.5%) than in the Cryo-PVI alone group (n=69, 53.1%; absolute difference, -15.6% [95% CI, -27.9% to -3.4%]; hazard ratio, 0.66 [95% CI, 0.46-0.94]). Antiarrhythmic drugs were prescribed after the 3-month period to 72 (49.3%) patients in the additional RA ablation group and 79 (55.2%) patients in the Cryo-PVI alone group. No difference was found in complication rate between the 2 groups. Total procedure time was longer in the additional RA ablation group (median, 88 versus 72 minutes; P<0.001).

Conclusions: Additional RA linear ablation beyond Cryo-PVI improved the ablation outcome compared with that of PVI alone in persistent AF patients.

Keywords: anti-arrhythmia agents; atrial fibrillation; atrial septum; pulmonary veins; vena cava, superior.