Cryoballoon Ablation of the Left Common Pulmonary Vein Using a Size-Adjustable Cryoballoon: A Comparative Study

The efficacy of cryoballoon ablation (CBA) using a 28-mm or 31-mm cryoballoon for isolating the left common pulmonary vein (LCPV) remains poorly established. We aimed to evaluate procedural outcomes and long-term follow-up data of CBA for the LCPV using either POLARx with a fixed 28-mm cryoballoon or POLARx FIT with a size-adjustable 28-mm or 31-mm cryoballoon.

Patients with LCPV who underwent CBA for atrial fibrillation using POLARx or POLARx FIT between January 2022 and April 2024 were retrospectively analyzed. Procedural outcomes and long-term follow-up data were compared between the POLARx and POLARx FIT groups.

Fifty-one patients (32 males [62.7%]; mean age, 66 ± 11.6 years) were analyzed. The POLARx group included 23 patients, and the POLARx FIT group included 28 patients. First-freeze pulmonary vein isolation (PVI) success was 1 (4.3%) versus 8 (28.6%) (p = 0.03), and radiofrequency touch-up ablation was required in 2 (8.7%) versus 0 patients (p = 0.2) in the POLARx and POLARx FIT groups, respectively. Nadir temperature was -53.6° ± 4.7°C versus -54.7° ± 5.6°C (p = 0.45); the number of applications was 3.2 ± 1 versus 2.3 ± 0.9 (p < 0.01); and total freezing time was 520.9 ± 164 s versus 377.7 ± 129.9 s (p < 0.01) for the POLARx and POLARx FIT groups, respectively. A single gastric hypomotility case was observed in the POLARx FIT group. The 1-year arrhythmia-free survival rates were 81.8% and 78.7% for the POLARx and POLARx FIT groups, respectively (p = 0.96).

POLARx FIT was useful for LCPV isolation, with a higher first-freeze PVI success rate, fewer applications, and shorter total freezing time compared to POLARx.