A morphometric study of the distribution of early coronary atherosclerosis using arteriography

In order to document the localized prevalence of early atherosclerosis in the major coronary arteries, a study using 50 coronary arteriographies was made from Feb. 1984 to Sep. 1985 in Shinshu University Hospital. Early atherosclerotic stenosis had a spatial distribution with strong incidence on the LAD bifurcations which contained the first diagonal branch, RCA which contained RV branches and LCX which contained the OM branch. Upstream of the bifurcations, the stenotic changes were observed to be concentric with the vessel axes. Downstream of the flowdivider, the lesions were gathered proximally and quickly disappeared distally. Lesions tended to occur eccentrically at the lateral walls of the entrance of the smaller branch. The proximal portions of both the RCA and LCA were almost free of disease. We also tried to investigate the relationship between the bifurcation angle branching off the parent vessels and early sclerotic lesions. We found that the angle between the branches and the plane in contact with the surface of the heart is especially important.