Objective: To evaluate the CT imaging characteristics of incomplete and complete myocardial bridges-mural coronary artery (MB-MCA).
Methods: Fifty subjects with dual source coronary CT angiography (DSCTA) evidenced MB were included. The subjects were divided into incomplete MB-MCA and complete MB-MCA groups. The diameter of MCA in best systole phase and diastole phase, the MCA stenosis rate, the presence of atheromatous change proximal to the MB were evaluated.
Results: There were 58 MB, the average length was (2.02 ± 1.02) cm, 23 were incomplete MB and 35 were complete MB. Thirty-two MB were in the middle segments of left anterior descending artery (55.2%); 17 MB were in the distal segment of the left anterior descending artery (29.3%); 1 MB was in the proximal segment of left anterior descending artery; 3 MB in diagonal branch; 4 MB in obtuse marginal branch, 1 MB in distal right coronary artery. It was statistically significant difference between the incomplete MB-MCA and the complete MB-MCA of the diameter change in diastole and systole phase [(1.93 ± 0.49) mm, (1.71 ± 0.45) mm vs. (2.21 ± 0.41) mm, (1.63 ± 0.52) mm, P = 0.008] and stenosis rate (10.38% ± 20.2% vs. 25.12% ± 21.02%, P = 0.01). Atherosclerotic finding was evidenced in 8 incomplete MB (34.78%) and 15 complete MB (42.86%) at the proximal vessel of mural coronary artery (P > 0.05).
Conclusion: DSCTA can vividly display the incomplete and complete myocardial MB, accurately evaluate the shape change of MB-MCA in diastole and systole phase and detect the atherosclerotic change in the proximal vessel of MB.