Comparison of pulmonary veins anatomy in patients with and without atrial fibrillation: analysis by multislice tomography

Abstract

A possible role of anomalies in number and insertion of pulmonary veins (PV) in initiating atrial fibrillation (AF) has been suggested. It has been shown as well that changes in anatomy of PVs such as enlargement may have an effect on arrhythmogenesis. The aim of the study was to compare anatomy of the left atrium (LA) and PVs in patients with AF and control subjects.

Methods: Eighty two patients were evaluated with 64-slice computed tomography (MSCT). Fifty one of them were referred to catheter ablation with history of highly symptomatic AF--AF(+) group. Thirty one control subjects had no history of AF and were referred to MSCT for noninvasive evaluation of different pathologies which finally were excluded--AF(-) group. Study groups did not differ in regard to age, sex, presence of hypertension and left ventricular systolic function. Diameters of PV ostia were measured in anterior-posterior (AP) and superior-inferior (SI) directions. Venous ostium index was calculated as a ratio between these measurements.

Results: The diameter of LA was higher in AF(+) patients than in the AF(-) patients (39±6 mm vs. 35±4 mm, p<0.005). In 68.6% of AF(+) patients and in 83.9% of AF(-) patients the anatomical pattern was typical with two right and two left PVs. Additional PVs were detected in 6 patients, only in AF(+) group (p<0.05). Common ostia were more frequently found in AF(+) subjects (37.2% vs. 19.3, p=0,08), mainly left-sided. In AF(+) group mean SI diameters of both-sided superior PVs and left inferior veins were larger. All AP diameters except for right inferior PVs were also larger in AF(+) group than in control cases.

Conclusions: Variations in the PVs anatomy are more common and diameters of ostial portions of the veins are larger in AF patients than in control subjects. These findings suggest that further studies on the role of structural abnormalities of PVs in arrhythmogenesis are needed.