Features of myocardial bridge based on computed tomography angiography / 第二军医大学学报

ABSTRACT

Objective To analyze the pathological and anatomic features of myocardial bridge (MB) using coronary computed tomography angiography (CTA), so as to deepen the understanding of MB. Methods The data of 1 658 patients with MB diagnosed by coronary CTA were retrospectively analyzed. The distribution of MB in the coronary system were analyzed, the length of mural coronary artery (MCA) and average systolic stenosis rate of different types of MB were measured, and the anatomic morphological differences of different types of MB were statistically analyzed. Results Among the 1 658 patients, 1 606 (98.86%) were single MB in single coronary artery, 9 (0.54%) were multiple MB in single coronary artery, and 43 (2.60%) were single MB in different coronary arteries. A total of 1 606 MB lesions in 1 559 cases (94.03%) were located at the left anterior descending (LAD) coronary artery, 87 MB lesions in 81 cases (4.88%) at the left circumflex (LCX) coronary artery, and 19 MB lesions in 18 cases (1.09%) at the right coronary artery (RCA). There were 1 244 cases (75.03%) of incomplete MB, 362 cases (21.83%) of complete MB, and 52 cases (3.14%) of complex MB with the features of both types. The length of MCA in the complex MB was significantly longer than that of the complete MB ([24.32±4.02] mm vs [16.13±1.27] mm, P50% (31.19% [388/1 244] vs 41.16% [149/362]), incidence of proximal coronary artery disease (9.41% [117/1 244] vs 35.08% [127/362]), positive rate of ischemic symptom (32.88% [409/1 244] vs 58.29% [211/362]), and positive rate of ischemic electrocardiogram (37.78% [470/1 244] vs 65.75% [238/362]) of the incomplete MB were significantly lower than those of the complete MB (all P<0.05). Conclusion MB lesions mainly locate at LAD coronary artery and are single MB in single coronary artery. MB-MCA morphology can be divided into complete, incomplete and complex types by coronary CTA, with incomplete type being the main type, and each type of MB has different clinical and morphological features.