The Functional Importance of Coronary Collaterals

T HE PHYSICIAN attending a patient with a recent coronary occlusion is confronted with many questions of prognostic importance: How long will muscles in the ischemic area remain viable? What will determine the size, shape, and depth of the infarct? What are the chances that collateral blood supply will limit its extent, promote healing, and prevent subsequent aneurysmal dilatation? Are drugs likely to be helpful? Careful clinical observations followed by necropsy control can suggest answers to these questions; basic knowledge derived from experimental studies helps to establish the correctness of the answers.