Failure of nifedipine and reperfusion to reduce infarct size relative to region at risk as measured by NADH fluorophotography.

In this report we describe a new technique for the measurement of region at risk after coronary artery ligation in the rabbit by NADH fluorophotography. We also describe the application of this technique to a study of nifedipine combined with reperfusion in experimental myocardial infarction. In 16 untreated rabbits the epicardial surface area of NADH fluorescence immediately after coronary ligation correlated with infarct size at 24 hr after coronary occlusion, as measured by nitro blue tetrazolium staining (r = .84, p less than .001). In 24 rabbits we studied the effect of nifedipine administered immediately after coronary ligation and combined with reperfusion at 1 hr after occlusion. Nifedipine had no significant effect on region at risk or infarct size.