Published online Aug 6, 2019. doi: 10.12998/wjcc.v7.i15.1986
Peer-review started: March 28, 2019
First decision: May 31, 2019
Revised: June 12, 2019
Accepted: July 3, 2019
Article in press: July 3, 2019
Published online: August 6, 2019
More and more reports indicate that myocardial bridge (MB) can compress the mural coronary artery during cardiac contraction, causing myocardial ischemia such as angina pectoris and myocardial infarction. It is clinically called MB-related coronary heart disease (CHD). Therefore, the relationship between MB and CHD has an important influence on the diagnosis of MB-related CHD. Currently, only when the MB reaches a certain thickness, it can be found in coronary angiography (CAG), which results in a high missing diagnosis rate.
Currently, CAG cannot specifically observe MB-related details. Computed tomography coronary artery (CTA) has become an important means of non-invasive diagnosis of CHD. Studies have shown that CTA can directly show the anatomical relationship between the coronary artery and myocardium. Therefore, this study used CTA to assess the association between MB and coronary atherosclerosis, in order to explore the effect of MB on patients with CHD and improve the detection rate of MB-related CHD.
In this study, CTA was used to observe the anatomy of MB and analyzed the effects of MB thickness, systolic compression, diastolic compression, and MCA systolic stenosis rate on CHD. The purpose of this study was to evaluate the relationship between MB and coronary atherosclerosis by CTA.
CHD patients who underwent CTA or CAG were defined as the CHD group and the control group, respectively. CHD patients with combined MB were defined as the MB-CHD subgroup. Patients with simple MB were defined as the simple MB subgroup. The anatomical features of patients with MB were analyzed by multi-factor logistic regression. The ROC curve was used to analyze the diagnostic efficacy of the potential indicators for MB-related CHD.
MB thickness, systolic compression, diastolic compression, and MCA systolic stenosis had significant effects on the incidence of MB-related CHD (P < 0.05). The areas under the ROC curves for the four indicators in diagnosing CHD were 0.814, 0.755, 0.870, and 0.795, respectively. The efficacy of diastolic compression in the diagnosis of CHD was the highest. When the degree of MB diastolic compression was > 48.68%, the risk of CHD was 15.953 times than that when the value was ≤ 48.68% (P < 0.05).
MB length, MB thickness, systolic and diastolic compression of MCA have significant effects on the occurrence of MB-related CHD.
CTA is a non-invasive economic examination that can directly display the anatomical relationship between the coronary arteries and myocardium. The combination of the four MB anatomical features has potential diagnostic value for MB-related CHD. However, the results of this study cannot be regarded as the clinical criteria because of the limited sample size. We suggest that further multi-center study should be performed to obtain the effective indicators for MB-related CHD, in order to provide a reference for early diagnosis of MB.