Serum Enzymes in Experimental Myocardial Infarcts

THERE IS no known accurate technique of clinical quantitation of myocardial infarct size.1During the past decade practical methods of measuring the serum values of certain enzymes, present in abnormally elevated levels in the presence of myocardial necrosis, have been applied widely as diagnostic tests for the presence of myocardial infarction. The reliability of the correlation of infarct size with the magnitude of serum enzyme elevation has not been precisely established. A method based on myocardial distribution of intravenously administered radioactive rubidium (86Rb) has been used recently to quantitate the size of experimentally produced myocardial infarcts. In the present study the elevation of the serum glutamic oxaloacetic transaminase (SGOT), lactic dehydrogenase (LDH), and heat stable lactic dehydrogenase (LDH) following coronary artery ligation was assessed in relation to myocardial infarct size as determined by macroscopic examination (dissection) at autopsy and by the radioactive rubidium distribution technique Methods Myocardial infarcts