The spectrum of atherosclerosis burden in each segment of coronary artery tree.

The coronary artery tree was classified into 16 segments according to American Heart Association classification 1] proximal, 2] mid, 3] distal right coronary artery; 4] posterior descending artery; 5] left main artery; 6] proximal, 7] mid, 8] distal left anterior descending artery; 9] first, 10] second diagononal branch; 11] proximal, 13] mid, 15] distal left circumflex artery; 12] first, 14] second obtuse marginal branch; 16] posterolateral ventricular branch]. The degree of stenosis and composition of plaque of each segment was evaluated. The incidence of plaque and proportion of plaque (CP, MP, NCP) were noted on each segment in fig 2 (top). The degree of stenosis of each segment was classicized into four groups: 0 for normal, 1 for <50%,2 for 50% to 69%, 3 for ≥70% and their proportion were recorded in fig 2 (lower). CP = calcified plaques. MP = mixed plaques. NCP = non-calcified plaques.