Significance of the anatomical properties of a myocardial bridge in coronary heart disease

Circ J. 2011;75(7):1559-66. doi: 10.1253/circj.cj-10-1278. Epub 2011 Mar 31.

Abstract

A myocardial bridge (MB), partially covering the coronary artery, is a congenital anatomical variant usually present in the left anterior descending coronary artery (LAD). MB causes coronary heart disease (CHD) by 2 distinct mechanisms influenced by the anatomical properties of the MB, such as its length, thickness, and location. One is direct MB compression of the LAD at cardiac systole, resulting in delayed arterial relaxation at diastole, reduced blood flow reserve, and decreased blood perfusion. The other is enhancement of coronary atherosclerosis causing stenosis of the LAD proximal to the MB, occurring because of endothelial injury arising from the abnormal hemodynamics provoked by retrograde blood flow up toward the left coronary ostium at cardiac systole. The magnitude of the effect of the 2 distinct mechanisms of the MB on LAD blood flow is prescribed by a common root of the MB-muscle mass volume generated by those properties. Furthermore, the anatomical properties of the MB are closely associated with the choice of treatment and therapeutic outcome in CHD patients having an MB. Thus, the anatomical properties of an MB should be considered in the diagnosis and management of CHD patients with this anomaly.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Adrenergic beta-Antagonists / therapeutic use
  • Cardiovascular Surgical Procedures
  • Coronary Disease / pathology*
  • Coronary Disease / physiopathology*
  • Coronary Vessel Anomalies / pathology
  • Coronary Vessel Anomalies / physiopathology
  • Coronary Vessels / pathology
  • Coronary Vessels / physiopathology
  • Humans
  • Myocardial Bridging / pathology*
  • Myocardial Bridging / physiopathology*
  • Myocardial Bridging / therapy
  • Regional Blood Flow / physiology
  • Stents

Substances

  • Adrenergic beta-Antagonists