Incidence and clinical significance of bridges of myocardium over the coronary arteries and their branches.

The incidence of bridges of myocardium seen on the external surface of the heart, through the epicardium, over portions of coronary arteries and their branches, was studied in 50 cadavers and found to be 78%. The bridges of the myocardium varied in size and in number (from one to six). Their location was predominantly found at the level of the anterior ventricular branch of the left coronary artery also called left anterior descending artery (52%), whereas in the territory of the right coronary artery the highest percentage was at the level of the anterior ventricular branch (12%). This myocardio-arterial relationship might be responsible for periodic or permanent reduction of the lumen, partial or total arterial obliteration, ischemia, atherosclerosis, angina, and sudden death.