Long-term Durability of Posterior Wall Isolation Using the Cryoballoon in Patients with Persistent Atrial Fibrillation: a Multicenter Analysis of Repeat Catheter Ablations

Purpose: There is a growing interest in performing pulmonary vein isolation (PVI) with concomitant posterior wall isolation (PWI) using the cryoballoon for the treatment of patients with persistent atrial fibrillation (AF). However, there is little known about the long-term durability of PWI using this approach.

Methods: In this multicenter study, we retrospectively examined the durability of PVI + PWI using the 28-mm cryoballoon by investigating the outcomes from consecutive patients referred for repeat catheter ablation.

Results: Altogether, 81/519 patients (15.6%) were referred for repeat catheter ablation. Repeat ablation was associated with a longer AF duration, hypertension, heart failure, multiple cardioversions, and antiarrhythmic therapy as well as larger left atrial (LA) diameters (49 ± 4 mm versus 43 ± 5 mm; P < 0.001) and greater need for "touch-up" (adjunct) radiofrequency ablation (44.4% versus 18.3%; P < 0.001). LA diameter also emerged as a significant predictor for adjunct radiofrequency ablation (P < 0.001). Durable PVI was observed in 66/81 patients (81.5%) and PWI in 67/81 patients (82.7%). Those with incomplete PWI exhibited larger LA diameters, particularly > 48 mm (negative predictive value = 89.7%). Lastly, an atypical LA posterior wall/roof flutter represented the third most common cause of arrhythmia recurrence and essentially every patient with incomplete PWI exhibited such an arrhythmia.

Conclusion: PWI performed using a 28-mm cryoballoon in conjunction with PVI exhibits long-term durability in the vast majority of patients with persistent AF. While LA diameter (particularly > 48 mm) is a significant predictor for the need for adjunct radiofrequency ablation when performing this technique, those with incomplete PWI invariably present with an atypical flutter using this substrate.