Characterization of pulmonary vein morphology using multi-detector row CT study prior to radiofrequency ablation for...

To classify the drainage patterns of the pulmonary veins as depicted by multi-detector row CT and to measure their ostial diameters.

Over a period of two years contrast material-enhanced 64-slice CT scans were performed in 188 consecutive patients who were referred to our department for cardiac CT study prior to ablation of atrial fibrillation with radiofrequency energy. A classification was formulated based on both the number of venous ostia on each side and the pulmonary vein drainage patterns. The frequency of each pattern was determined and the diameters of the pulmonary vein ostia were measured.

Most patients had two ostia on the left side (n=158; 84%) and on the right side (n=161; 85.6%). Thirty patients (16%) had variant anatomy on the left: common ostium (n=24; 12.8%), accessory lingular vein (n=5; 2.7%) and accessory upper lobe vein (n=1; 0.5%). Twenty-seven patients (14.4%) had variant anatomy on the right: accessory middle lobe vein (n=20; 10.6%), accessory upper lobe vein (n=2; 1.1%), accessory lower lobe vein (n=4; 2.1%) and common ostium (n=1; 0.5%). Mean pulmonary vein anterior-posterior and superior-inferior ostial diameters were variable: right superior, 17.9 +/- 3.4 mm and 18.2 +/- 2.9 mm; left superior, 16.2 +/- 2.9 mm and 17.0 +/- 2.7 mm; right inferior, 16.4 +/- 2.9 mm and 16.9 +/- 2.6 mm; left inferior, 15.2 +/- 2.6 mm and 16.5 +/- 2.5 mm.

Multi-detector row CT provides a valuable means for mapping pulmonary vein anatomy prior to atrial fibrillation ablation. A system for classifying pulmonary venous anatomy was developed.