Pulmonary vein anatomical variants and incidence of atrial fibrillation

Background The role of the pulmonary veins (PV) in the pathogenesis of atrial fibrillation (AF) has been well described, as have the most frequently seen anatomical variants of these veins. Prior studies have shown conflicting evidence on the potential association of PV variants and incidence of AF. We sought to further clarify the association between PV variants and atrial fibrillation. Methods We conducted a single-institution retrospective case-control study of patients with AF and without AF who had undergone cardiac CT imaging from 2018 to 2021. We documented patient characteristics and cardiac anatomical features including PV variants, LV ejection fraction and left atrial volume/diameter. Results 742 patients were included: 480 with AF and 262 without. There was a male predominance in our atrial fibrillation group of 67.3%. There was higher incidence of PV variants (40.5%) than established studies. We demonstrated a significant difference in the frequency of PV variants between the AF and control groups overall (44.3% vs. 33.2%, respectively, p = 0.003), AF and the presence of right middle PV (p < 0.001), chicken wing left atrial appendage morphology (p = 0.005), sleep apnea and left atrial size (both p < 0.001). Both right middle PV, sleep apnea, and left atrial size remained significant in multivariable analysis (all p < 0.01). Conclusion PV variants are more common than previously reported, and the presence of an accessory right middle pulmonary vein has a significant relationship with atrial fibrillation.