RESPONSE OF SERUM INDICATORS OF MYOCARDIAL-INFARCTION FOLLOWING EXERCISE-INDUCED MUSCLE INJURY

The purpose of this investigation was to determine the response of thr ee parameters used in the assessment of acute myocardial infarction (A MI) after a single bout of eccentric exercise designed to elicit skele tal muscle injury. Total creatine kinase (CK), CK-MB isoenzyme (CK-MB) , and the leukocyte differential were determined after a 20-minute ben ch-stepping exercise in 21 men ranging in age from 30 to 45 years. Com parison of several criteria showed that the use of CK-MB or the relati ve lymphocyte percentage alone resulted in 11% and 1.8%, respectively, of data collection points exceeding cutoff values suggestive of AMI. However, the use of both parameters in combination completely eliminat ed false-positive results with no data collection points meeting the c riterion. It is thus suggested that CK-MB activity in conjunction with the relative lymphocyte percentage may not only provide incremental v alue in the detection of AMI but also reduce the incidence of misdiagn osis associated with exercise. Copyright (C) 1998 by W.B. Saunders Com pany.