Functional Importance of the Coronary Collaterals

POST-MORTEM studies have demonstrated the presence of many coronary arterial collateral vessels in the normal human heart at birth and later in life. Some of these vessels are located in the epicardium, but they are much more prevalent in the subendocardium. Coronary-artery disease leads to an increase in their size and number in both regions, but the increase is greater in the subendocardium than in the subepicardium.1 , 2 The subject of this article is the extent to which the development of collateral vessels protects the heart from the consequences of coronary-artery disease, especially in human beings. The understanding of this issue . . .