Pulmonary vein volume and myocardial sleeve extension estimated by 3D computed tomography and voltage mapping predict arrhythmogenic triggers of paroxysmal atrial fibrillation

Purpose: Relationship between pulmonary vein (PV) anatomy and the pathophysiology of paroxysmal atrial fibrillation (PAF) remains incompletely studied. The aim of this study was to determine whether PV anatomy predicts arrhythmogenic PVs.

Methods: Twenty-six consecutive PAF patients with spontaneous PAF or consistently frequent ectopic beats during electrophysiological study were enrolled. Computed tomography (CT) images for PVs were reconstructed into 3D images. The PV diameter and volume were measured based on the 3D images. The PV myocardial sleeve area was measured based on the 3D voltage mapping results. The PV myocardial sleeve area index was calculated by dividing the sleeve area of each PV by the average sleeve area of all PVs in each patient.

Results: The diameter and volume of the arrhythmogenic PVs were larger than those of the non-arrhythmogenic PVs (21.08 ± 4.57 mm vs. 16.47 ± 3.31 mm, P < 0.001 and 7.70 ± 3.28 cm³ vs. 4.09 ± 1.99 cm³, P < 0.001, respectively). The myocardial sleeve area and sleeve area index of the arrhythmogenic PVs were also larger than those of the non-arrhythmogenic PVs (8.62 ± 5.33 cm² vs. 4.77 ± 3.84 cm², P < 0.001 and 1.59 ± 0.35 vs. 0.81 ± 0.38, P < 0.001, respectively). Multivariate analysis showed the PV myocardial sleeve area index was the independent predictor for arrhythmogenic PVs (P < 0.001).

Conclusions: PV size plays an important role in triggering PAF. A large myocardial sleeve extension is a powerful and independent predictor for arrhythmogenic PV, which may be useful anatomical markers to facilitate PAF ablation.