Proof of concept - retrospective virtual reality pulmonary veins modeling evaluating eligibility for atrial fibrillation cryoballoon ablation

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Abstract Background Cryoballoon pulmonary vein isolation (PVI) requires circumferential vein occlusion ("seal") to enable durable lesion delivery. Anatomical mismatch may preclude effective seal and contribute to procedural failure. We evaluated whether a patient-specific virtual "seal" model can specifically identify patients unlikely to be anatomically suitable for cryoballoon PVI [1,2]. Purpose To assess whether patient-specific virtual cryoballoon seal modeling can specifically identify patients anatomically unsuitable for cryoballoon PVI. Methods We analyzed 50 atrial fibrillation patients undergoing cryoballoon PVI with pre-procedural CT-based segmentation of individual pulmonary veins (PVs) and ≥1-year follow-up. A digital cryoballoon model was virtually positioned within each PV and scored for seal (1=sealed, 0=unsealed). Patient-level "non-suitability" was defined as ≥1 PV predicted not to seal. Patients were categorized into three groups: (1) no recurrence + complete seal, (2) recurrence + complete seal, and (3) recurrence + any non-seal. Baseline characteristics were compared across groups (Table 1). Discordance between modeled seal status and clinical recurrence was assessed using McNemar’s test (two-sided α=0.05); associations between baseline factors and outcomes were explored with chi-square/Fisher testing as appropriate. Results All patients without recurrence (25/25) demonstrated complete modeled seal. Among patients with recurrence (n=25), only 4/25 had any modeled non-seal (7 unsealed PVs across 4 patients; involving all PV locations), while 21/25 recurred despite complete modeled seal. The distribution was significantly asymmetric by McNemar testing (p < 0.001), driven by the fact that modeled non-seal occurred exclusively among recurrence cases (no false positives). Conclusions Virtual cryoballoon seal modeling appears to function as a high-specificity screening tool to flag a small subgroup of patients who may be anatomically unsuitable for cryoballoon PVI and may benefit from alternative strategies (e.g., RF ablation) or tailored planning. Most recurrences occurred despite predicted complete seal, suggesting that factors beyond anatomic occlusion (procedural indices and atrial substrate) govern durability in the broader population [3-5].