[A clinical study of the relation between time to reperfusion and infarct size]

Observations made in animal models of reperfusion in acute myocardial infarction have shown that early reperfusion results in myocardial salvage. But the relation between the time of reperfusion and myocardial salvage is not clear in human patients. If earlier reperfusion provides smaller infarct size, reperfusion therapy initiated in the first 1 hour should be the most beneficial. In this study, we compared the results of therapy initiated in the first 1 hour (group A, n = 19) with treatment started 1 to 24 hours after the onset of chest pain (group B, n = 652). The infarct location, development of collateral vessels, number of diseased vessels and reperfusion rate of thrombolysis in the two groups didn't differ. There was a statistically insignificant trend towards total occlusion of the infarct artery in group A (89.5% vs 69.7%, p less than 0.1). Peak CPK and changes in left ventricular ejection fraction (delta EF) were assessed in patients with total occlusion of the left anterior descending artery and successful reperfusion (n = 8 in group A, n = 120 in group B). There was no difference in peak CPK (3281 +/- 2192Iu/l vs 3490 +/- 1811Iu/l) and delta EF (6.3 +/- 17.1% vs 5.8 +/- 11.9%). These findings suggest that there is no relation between the time of reperfusion and myocardial salvage in human patients.