Anatomic variants of pulmonary venous drainage and their relation to recurrences of atrial fibrillation after pulmonary vein isolation

Abstract

Anatomical variants of pulmonary venous drainage in the left atrium are often found. Divergent results have been reported on the impact of variant anatomy on atrial fi brillation (AF) recurrence after catheter ablation. We aimed to study the frequency of different anatomical variants of pulmonary venous drainage and their relationship with documented recurrences of AF after ablation. Material and methods: A retrospective study of patients with AF in whom radiofrequency pulmonary vein isolation was done after previously performed cardiac contrast-enhanced multidetector computed tomography. Clinical and procedural characteristics, type and frequency of anatomical variants of the veno-atrial junction and their association with AF recurrences were studied. Results: One hundred seventy-seven patients (112 men, 63.3%) with AF were studied, of which 148 (83.6%) with paroxysmal AF. Variant anatomy was found in 91 patients (51.4%). In 20.9% there was a common left trunk, in 23.2% – more or less than two right-sided veins, and in 7.3% – variations for both right and left veins. No differences in clinical and procedural characteristics were found between the groups with normal and variant anatomy. Recurrences of AF and their association with pulmonary venous anatomy were studied in 104 patients with follow-up ≥ 3 months. No signifi cant relation was found between the presence of variant anatomy and AF recurrences within the blinding period after ablation, OR = 0.864, 95% CI = 0.397 – 1.88, p = 0.843, nor afterwards, OR = 1.12, 95% CI = 0.5 – 2.5, p = 0.839. Cox regression analysis showed no differences in AF recurrence-free survival regardless of the anatomical variant of pulmonary venous drainage, HR = 1.09, 95% CI = 0.58 – 2.05, p = 0.779. Conclusion: In this local population of patients with AF, the incidence of variant pulmonary venous drainage is just over 50%. No association was found between variant anatomy and the rate of AF recurrences after fi rst pulmonary vein isolation.