Non-Occlusive Separate Freezing for Cryoballoon Pulmonary Vein Isolation to the Large Pulmonary Vein

Cryoballoon pulmonary vein (PV) isolation (PVI) requires PV occlusion, which can be challenging to the large PV. The non-occlusive separate freezing, which involves freezing the superior and inferior portions of the PV ostium without complete occlusion, is often useful in these situations. This study aimed to evaluate the efficacy and long-term results of the non-occlusive separate freezing technique and compare the treatment details of POLARx and Arctic Front Advance Pro (AFA-Pro).

Patients who underwent cryoballoon PVI using the non-occlusive separate freezing between September 2019 and April 2023 in our institution were analyzed and followed up for 1 year. Success rates of PVI by non-occlusive separate freezing and treatment outcomes were compared between POLARx and AFA-Pro. The 1-year arrhythmia-free survival was also evaluated.

Overall, 135 PVs were analyzed (POLARx, n = 63; and AFA-Pro, n = 72). The success rates of PVI for the POLARx and AFA-Pro were 55/63 (87.3%) and 52/72 (72.2%), p = 0.04. The nadir temperatures for the POLARx and AFA-Pro were -52.2 ± 4.7°C and -42.4 ± 7.4°C, p < 0.001. No phrenic nerve injury occurred in either group, but two cases of gastric hypomotility were observed using POLARx. The 1-year arrhythmia-free survival rates for POLARx and AFA-Pro were 86.4% and 81.2%, p = 0.47.

The success rate of PVI using the non-occlusive separate freezing technique was approximately 80% and was significantly higher with POLARx than with AFA-Pro. The 1-year arrhythmia-free survival rate was not significantly different.