Myocardial Bridge: Evaluation on MDCT

Abstract

The correlation between myocardial bridge and atherosclerotic changes has been controversial. The aim of this study was to evaluate the relation between myocardial bridge and atheromatous coronary artery disease (CAD). Three hundred consecutive subjects who underwent coronary CT angiography (CTA) were included in this study. The prevalence, length, depth, precise location, and concomitant atheromatous changes were evaluated. The group of subjects with myocardial bridge was compared with another subgroup, the control group, which included subjects without myocardial bridge. From a total of 300 subjects, 78 subjects (26%) were found to have one myocardial bridge each. The mid left anterior descending artery (LAD) was the most common coronary artery involved (48/78). A significant difference was found between the LAD myocardial bridge group and the control group regarding presence of atheromatous changes in a similar LAD segment proximal to the myocardial bridge (p < 0.0001) and in the severity of atheromatous changes in these segments (mild, p < 0.0001; moderate, p < 0.02; and severe, p < 0.0001). The presence of stenosis in the LAD proximal to the myocardial bridge correlated with the thickness and length of the bridge. Myocardial bridge predisposes to the development of atherosclerosis in the coronary artery segment proximal to the bridge. This may indicate that myocardial bridge should be considered an anatomic risk factor in the evaluation of CAD.