Abstract：Objective: To study the size and shape of pulmonary vein(PV) ostia, its distance to the first bifurcation, and the variation of PV trunk as it approaches the left atrium. Methods: The data of 103 patients were collected in this study. Pulmonary venous drainage patterns to the left atrium were analysed. The caliber of PV and distance to the first bifurcation were measured, and venous ostial index(VOI) were calculated. Results: Most patients(n=81, 78.6%) had four standard PVs. The caliber of superior PV ostia was larger than that of the inferior PV ostia. The right superior and inferior PV ostia were larger than the left PV ostia respectively(P<0.05). The VOI of the right was larger than that of the left. The caliber of PV in men was larger than that in women(P<0.05). The VOI between men and women was similar(P>0.05). The distance to the first bifurcation of each PV varied. They were different between the left and the right, the superior and the inferior PV(P<0.05). The PV ostial branches emergence rate of the right inferior PV(74.7%) was the highest and that of the left superior PV(3.2%) was the lowest. The caliber of some left inferior PV(55.6%) gradually decreased and the others increased as they entered the left atrium. All of the PV shapes gradually became oval. Conclusion: The PVs have a great anatomic variations. There is significant variability in PV caliber, shape and ostial branches emergence rate. Particular care must be taken when the left inferior PV is evaluated for its stenosis, as it usually narrows as it enters the left atrium.
2009, Vol. 20 
