Impact of left atrial anatomy on pulmonary vein isolation with cryoballoon ablation: Insights from the randomized controlled COMPARE CRYO study.

Background Cryoballoon ablation is an established therapy for pulmonary vein (PV) isolation (PVI).Objective This study aimed to explore whether specific left atrial anatomical features are associated with both first-pass PVI success and long-term outcomes after cryoballoon ablation using 2 different cryoablation systems.Methods Left atrial reconstructions of patients with paroxysmal atrial fibrillation were analyzed. PVI was performed using either the Medtronic (Minneapolis, MN) Arctic Front Advance or the Boston Scientific (Marlborough, MA) POLARx cryoablation catheter. Anatomical features were assessed to predict first-pass PVI success after a single application and long-term outcomes on the basis of implantable cardiac monitor recordings.Results A total of 191 patients were enrolled (mean age 63.0 ± 9.8 years; 58 (30%) women). First-pass PVI was achieved in 69% of all procedures. Female sex was significantly associated with reduced first-pass isolation success, limited to the right superior PV (odds ratio [OR] 0.50; 95% confidence interval [CI] 0.26-0.97; P = .04). Anatomical predictors of failure of first-pass PVI included the absence of an orthogonal orientation of the left superior PV (OR 0.20; 95% CI 0.05-0.88; P = .033) and the left inferior PV (OR 0.36; 95% CI 0.13-0.99; P = .047) as well as the presence of a right middle PV for the right superior PV (OR 3.58; 95% CI 1.18-10.9; P = .024). The absence of an orthogonal orientation of the left superior PV was associated with atrial tachyarrhythmia recurrence (OR 4.12; 95% CI 1.90-9.11; P < .001).Conclusion The absence of an orthogonal orientation of the left-sided PVs was significantly associated with lower first-pass isolation rates and a higher risk of recurrence. These findings highlight the importance of preprocedural anatomical assessment to identify potential challenges and tailor ablation strategies.