Abstract 14789: Atrial Anatomical Variations Between Atrial Fibrillation Patients Compared to Other Subjects Without Atrial Fibrillation

Abstract

Introduction: In this study, we evaluated the anatomical atrial variations using gated cardiac computed tomography (CCT) between patients with and without atrial fibrillation (AF). Hypothesis: The aim of the study is to evaluate if there are specific anatomical characteristics that are associated with poor clinical outcomes following ablation in patients with AF. Methods: We retrospectively included 502 CCT scans of patients with AF prior to their pulmonary vein isolation procedure, and 1058 CCT scans of patients without AF performed to evaluate pulmonary vein anatomy and to rule out coronary artery disease between 2014 to 2017. Anatomical variations of the atria and interatrial septum included the Bachman bundle shunt (BBS - defined as a vascular channel crossing between the atria through the Bachman bundle), and atrial diverticulae. Results: Five-hundred and two patients with AF were older (67±14 vs. 63±13 years, P = 0.039), had a higher prevalence of diabetes mellitus (24.4% vs 14.7%, p = 0.006), and cerebrovascular disease (3.8% vs. 0.9%, p = 0.044) compared to patients without AF. Furthermore, CCTs analysis of AF patients demonstrated a significantly higher prevalence of BBS: (11% vs 4.1%, p <0.0001, left atrial diverticula (19% vs 7.7%), p <0.0001, and right atrial diverticula (9.8% vs 2.1%), P <0.0001 compared to patients without AF. Conclusions: This study is the first to analyze BBS and atrial diverticular prevalence in patients using CCT. We found that patients with AF are associated with a higher prevalence of structural atrial abnormalities including BBS, left and right atrial diverticula in comparison to individuals with no previous history of AF. Whether these anatomical variations influence AF incidence or AF recurrence after catheter ablation is yet to be determined.