USE OF C-11 ACETATE AND DYNAMIC POSITRON EMISSION TOMOGRAPHY TO ASSESS REGIONAL MYOCARDIAL OXYGEN-CONSUMPTION IN PATIENTS WITH ACUTE MYOCARDIAL-INFARCTION RECEIVING THROMBOLYSIS OR CORONARY ANGIOPLASTY

Carbon-11 (C-11) acetate has been introduced for the noninvasive measurements of myocardial oxygen consumption. This study was designed to assess regional C-11 acetate clearance in patients with acute myocardial infarction. Thirty-one patients were studied within 8 days of acute myocardial infarction. C-11 acetate washout-rate constants were significantly lower in the infarct territory than in the remote myocardium (p < 0.008). The scintigraphic measurements correlated with heart rate-blood pressure product in the remote as well as infarct areas (0.52 and 0.48, respectively). There was no significant correlation to left ventricular ejection fraction. C-11 washout rates were significantly affected by beta-receptor therapy as assessed by multiple regression analysis. Thus, C-11 acetate kinetics allow noninvasive characterization of regional myocardial oxygen demand, which may be useful in assessing the extent of myocardial injury and myocardial oxygen demand of remote myocardium.