(P189) COMPARATIVE ANALYSIS OF ATRIAL ANATOMICAL VARIATIONS VIA COMPUTED TOMOGRAPHY ANGIOGRAPHY IN PATIENTS WITH AND WITHOUT ATRIAL FIBRILLATION

Background: We aim to investigate the atrial anatomical variations in patients with and without atrial fibrillation (AF) using cardiac computed tomography angiography (CCTA) and identify features associated with AF recurrence following pulmonary vein isolation.

METHODS AND RESULTS: We retrospectively reviewed 502 CCTAs of patients with AF performed prior to a pulmonary vein isolation procedure with 1058 CCTAs of patients without AF performed to rule out coronary artery disease between 2014 and 2017. Anatomical variations of both atria including left atrial diverticula (LAD), right atrial diverticula (RAD), Bachman bundle shunt (BBS) (arrows in Figure), and pulmonary vein anatomy were assessed.

Results: We found that patients with AF were older (6714 vs. 6313 years, P = 0.039), had a higher prevalence of diabetes (24.4%) vs (14.7%), P = 0.006, and cerebrovascular accidents (3.8%) vs. (0.9%), P = 0.044 when compared with patients without AF. Furthermore, on CCTAs patients with AF demonstrated a significantly higher prevalence of BBS (11% vs. 4.1%, P < 0.001), LAD (19% vs. 7.7%, P < 0.001), and RAD (9.8% vs. 2.1%, P< 0.001) when compared to patients without AF. Logistic multivariable regression analyses of CCTA findings demonstrated increased Odd Ratios (OR) in those with AF of BBS (OR=3.51, 95% confidence interval (CI) = 2.32–5.35, P< 0.001), LAD (OR=2.94, 95% CI = 2.12–4.07, P< 0.001), RAD (OR=1.54, 95% CI=1.19–2.11, P=0.03), LA diameter (OR=2.42, 95% CI = 1.65-3.39, P< 0.001). Importantly, multivariate Cox regression showed that the LA dimension is a predictor of AF recurrence (HR=1.019, 95% CI =1.001-1.051, P=0.02).

Conclusion: AF patients have a higher prevalence of BBS, LAD, and RAD in comparison to patients without AF. Mean LA diameter predicts AF recurrence after the pulmonary vein isolation procedure.