Quantitative Studies of Extracoronary Blood Flow After Double Internal Mammary Artery Implantation
A technique for implanting both internal mammary arteries into left ventricular myocardial walls is described. Direct measurement of total and collateral coronary blood flow was made in terminal experiments six months after surgical implantation. The effluent from the right heart before and after occlusion of normal coronary arterial perfusion during extracorporeal circulation closely reflects total and collateral blood flow. An average flow of 70 ml/min, representnig 25% of normal coronary blood flow, was measured from double internal mammary artery implants plants in the ischemic canine heart. Lower flow rates (18 ml/min) were measured from similar double mammary artery implants into nonischemic hearts. Effective tissue perfusion from collateral pathways was demonstrated by metabolic studies which excluded arterioyenous shunting. The results of radiographic and microscopic examination were consistent with measured blood flows in each animal.
- © 1968 American Heart Association, Inc.