Impact of pulmonary vein sphericity and variant anatomy on outcomes after cryoballoon or pulsed field ablation

Background Pulmonary vein (PV) anatomy, including the sphericity index and variant anatomy has been repeatedly suggested as an important factor impacting on procedural and arrhythmic outcomes after single-shot pulmonary vein isolation (PVI). Aims This study analysed the impact of PV anatomy on procedural success and ablation outcomes and compared modality-specific effects between cryoballoon ablation (CBA) and pulsed field ablation (PFA). Methods This single-center analysis included patients undergoing CBA or PFA. The standard workup included a preprocedural cardiac computed tomography. Sphericity index (shortest vein diameter/longest vein diameter) for each vein and PV variant anatomy (common ostium, supplementary PVs) were systematically documented and correlated with acute procedural parameters as well as atrial fibrillation (AF) recurrence at 12-month follow-up. Results We included 1,519 patients (501 CBA, 1,018 PFA), with paroxysmal AF in 334 (66.7%) and 561 (55.1%) patients, respectively (p < 0.001). Common ostia were identified in 19.6% of patients, with comparable prevalence in paroxysmal (20.5%) and persistent AF (18.4%; p = 0.31). Procedural duration was slightly longer with CBA than with PFA (75.0 [62.0–97.5] vs 70.0 [50.0–97.0] min respectively, p<0.001), but fluoroscopy time was comparable (17.3 [13.1–23.2] vs 16.8 [12.6–24.3] min respectively, p=0.308). Sphericity indices showed limited association with acute procedural complexity. In CBA, only the left superior PV demonstrated modest predictive value for excessive cryo-applications (AUC 0.385 [0.278–0.493]; p=0.047). No parameter provided significant discrimination for procedure duration or fluoroscopy time in PFA. The presence of low-sphericity PVs (≤25th percentile) was not associated with AF recurrence for either modality (CBA: OR = 0.83, 95% CI 0.57–1.22, p = 0.352; PFA: OR = 0.85, 95% CI 0.63–1.15, p = 0.279). Recurrence rates were also similar between patients with standard vs common ostium PV anatomy and did not differ by ablation modalities in both paroxysmal and persistent atrial fibrillation (p=0.622 and p=0.061, respectively). Conclusion In this large cohort with standardised imaging and structured follow-up, PV sphericity and common ostium variants showed no meaningful association with procedural complexity or 12-month arrhythmia recurrence in either CBA or PFA. These findings support the anatomical robustness of both modalities and suggest that PV geometry has limited prognostic value in single-shot energy modality selection.