Pulmonary Vein Anatomy, Cooling Kinetics, and Recurrence After Cryoballoon Ablation for Atrial Fibrillation
Kuo‐Ming Yang, Hsiang‐Chiang Hsiao, Tung‐Chen Yeh, Chun‐Wang Chiou, Jeng‐Fung Hung, Cheng‐Hung ChiangABSTRACT
Background
Cryoballoon pulmonary vein isolation depends on balloon‐to‐ostium contact. We assessed whether computed tomography‐derived pulmonary vein ostial area (OA) and ovality index (OI) were associated with cooling after accounting for pulmonary vein (PV) branch and within‐patient clustering, and whether PV anatomy was associated with recurrence.
Methods
We retrospectively studied 120 patients with symptomatic atrial fibrillation undergoing second‐generation cryoballoon ablation. Vein‐level associations with nadir temperature, 1 min temperature, and time to isolation were assessed using linear mixed‐effects models with a patient random intercept and PV branch as a fixed effect; generalized estimating equations served as sensitivity analyses. Given 23 post‐blanking recurrences, logistic models were limited to left atrial volume index (LAVI) and one clinically selected covariate, with Firth‐penalized regression as a sensitivity analysis.
Results
All patients achieved acute PV isolation. Larger OA was associated with lower nadir temperature ( β = −0.583°C per 50 mm 2 ; 95% CI, −0.910 to −0.257; p < 0.001) and 1 min temperature ( β = −0.441°C per 50 mm 2 ; 95% CI, −0.764 to −0.118; p = 0.008) after branch and clustering adjustment. OI was not associated with either temperature outcome. Twenty‐three patients (19.2%) developed recurrent atrial arrhythmia. LAVI was associated with recurrence (adjusted OR, 1.659 per 10 mL/m 2 ; 95% CI, 1.250–2.201; p < 0.001), whereas persistent AF was not.
Conclusions
OA showed a modest association with cryoballoon temperatures but should not be used as a stand‐alone prognostic marker. LAVI remained associated with recurrence in parsimonious patient‐level analyses.