Second-Generation Cryoballoon Ablation for Atrial Fibrillation - A Detailed Analysis of the Impact of Left Atrial Volume Index on Clinical Outcome

Background: Pulmonary vein isolation (PVI) by means of cryoballoon is increasingly being used for the treatment of atrial fibrillation (AF). This study assessed whether the left atrial volume index (LAVI) predicts AF recurrence following PVI by means of 2nd-generation cryoballoon (Cryoballoon Advance; CB-A) when comparing persistent AF (PeAF) and paroxysmal AF (PAF).

Methods and results: Patients with drug-resistant AF and undergoing preprocedural computed tomography (CT) and PVI with CB-A were included. LAV was estimated from 3D CT images. A total of 417 patients with AF were included (95 PeAF, 322 PAF patients). After a mean of 22.1±9.4 months follow-up, 45/95 (47%) PeAF patients and 254/322 (79%) PAF patients had no recurrence. LAVI was an independent predictor for AF recurrence in PeAF patients (hazard ratio 1.042 per 1 mL/m; 95% confidence interval 1.006-1.080, P=0.02), but not in PAF patients. In PeAF patients with LAVI ≤61 mL/m, the freedom from recurrence was 78.5% vs. 22.2% in those with LAVI >61 mL/m (hazard ratio 5.771, 95% confidence interval 2.434-13.682, P<0.001), and the mid-term success rate was comparable with PAF patients.

Conclusions: LAVI predicted AF recurrence after PVI using CB-A in PeAF patients but not in PAF patients. If LAVI was ≤61 mL/m, the mid-term efficacy among PeAF patients was equivalent to that for PAF patients.