Time course of functional and biochemical recovery of myocardium salvaged by reperfusion

Abstract

To characterize the functional and biochemical recovery of myocardium salvaged by reperfusion, 19 anesthetized mongrel dogs underwent 2 hour occlusion of the proximal left anterior descending coronary artery, followed by reperfusion for up to 2 weeks. Thirteen dogs had a permanent occlusion and served as the control group. All dogs had serial two-dimensional echocardiograms and in vivo biopsies for adenosine triphosophate (ATP) and creatine phosphate after occlusion and at the time of sacrifice (6 hours, n = 15; 7 days, n = 6; or 14 days after occlusion, n = 11). The area of necrosis and area at risk of necrosis were identified in dogs sacrificed at 6 hours. After 4 hours of reperfusion, the area of necrosis determined by the triphenyltetrazolium chloride technique, expressed as a function of the area at risk by in vivo monastral blue injection, was 23.9 ± 5.8% (mean ± standard error of the mean) and largely subendocardial, compared with 89.1 ± 5.3% in dogs with permanent (6 hour) occlusion (probability [p] Thus, reperfusion after 2 hours of coronary occlusion resulted in recovery of jeopardized myocardium, in which the deterioration of function observed in nonreperfused tissue was reversed and biochemical improvement occurred over the course of 2 weeks. Computer-assisted two-dimensional echocardiography, a noninvasive but quantitative technique, appears well suited to monitor the rate of functional recovery of myocardium salvaged by reperfusion.