Prognostic implications of creatine phosphokinase levels after acute myocardial infarction--a study of low risk patients.

To determine the prognostic value of Creatine Phosphokinase (CPK) levels after acute myocardial infarction in patients thought to be at low risk of death or major complications, 94 consecutive patients with definite myocardial infarction were divided into two groups according to peak CPK levels. Group I contained 23 patients with a peak CPK of less than 1000 units and Group II contained 71 patients with a peak CPK level of greater than 1000. They were followed for six months or to death. A CPK of greater than 1000 was significantly associated with left ventricular failure, major arrhythmias and late death and seemed therefore to have value as an indicator of poor prognosis.