MYOCARDIAL INFARCTION FOLLOWING SURGICAL OPERATIONS

One hundred and forty-one randomly selected surgical patients, aged 35 years or over, were studied preoperatively, followed through their operative procedures, and reassessed during the first postoperative week for evidence of myocardial ischaemia associated with surgical operations under general anaesthesia. Of these patients 38% were found to have preoperative clinical evidence of heart disease, hypertension, or diabetes; 45% had abnormal preoperative E.C.G. patterns. Three patients experienced myocardial infarction during or within 36 hours of operation, all of the occult type ; all were in the preoperative abnormal groups. Non-specific postoperative E.G.G. changes were equally common in the groups of patients with normal or abnormal preoperative electrocardiograms. A relationship existed between a rise in serum lactic dehydrogenase (L.D.H.) concentration and the field of the operation, but the diagnosis of infarction was not confused provided serum L.D.H. isoenzyme patterns and a rise in serum aspartate aminotransferase (S.G.O.T.) levels were consistent with the diagnosis. © 1968, British Medical Journal Publishing Group. All rights reserved.