Observational Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Aug 6, 2019; 7(15): 1986-1995
Published online Aug 6, 2019. doi: 10.12998/wjcc.v7.i15.1986
Myocardial bridge-related coronary heart disease: Independent influencing factors and their predicting value
Dong-Hui Zhao, Qian Fan, Jun-Xia Ning, Xin Wang, Jia-Yu Tian
Dong-Hui Zhao, Qian Fan, Xin Wang, Jia-Yu Tian, Department of Cardiology, Beijing Anzhen Hospital Affiliated to Capital Medical University, Beijing 100029, China
Jun-Xia Ning, Department of Cardiology, The First People's Hospital of Pingyuan County, Dezhou 253100, Shandong Province, China
Author contributions: Zhao DH, Fan Q, and Ning JX designed the research; Zhao DH, Wang X, and Tian JY performed the research; Fan Q and Ning JX contributed new reagents/analytic tools; Zhao DH, Wang X, and Tian JY analyzed the data; and Zhao DH, Ning JX, and Tian JY wrote the paper.
Institutional review board statement: The study was approved by the Ethics Committee of Beijing Anzhen Hospital Affiliated to Capital Medical University.
Informed consent statement: All patients gave informed consent.
Conflict-of-interest statement: The authors declare that they have no competing interests.
STROBE statement: The authors have read the STROBE Statement, and the manuscript was prepared and revised according to the STROBE Statement.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Dong-Hui Zhao, MD, Doctor, Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, No. 2, Anzhen Road, Chaoyang District, Beijing 100029, China. zhaodonghui3486@126.com
Telephone: +86-10-64456548
Received: March 26, 2019
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
Research background

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.

Research motivation

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.

Research objectives

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.

Research methods

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.

Research results

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).

Research conclusions

MB length, MB thickness, systolic and diastolic compression of MCA have significant effects on the occurrence of MB-related CHD.

Research perspectives

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.