The effects of reperfusion of infarct-related coronary artery on serum creatine phosphokinase and left ventricular function.

In 31 patients with transmural myocardial infarction in whom coronary arteriography was performed within 8 hours after the onset of symptoms, we examined (1) the effect of restoration of coronary blood flow on serum CPK time-activity curve and (2) the relationship between cumulative CPKr and the left ventricular function in the chronic phase. We divided 31 patients into 2 groups: Group A consists of 19 patients in whom coronary reperfusion was established. Group B consists of 12 patients whose coronary artery remained occluded. In group A, the time required to reach peak serum CPK activity was significantly shorter than in group B. When comparing CPKr with percent abnormally contracting segment (%ACS) in 2 groups, correlation between CPKr and %ACS was not good, but it revealed linear relation in both group A and B. CPKr divided by %ACS (CPKr/%ACS) was significantly higher in group A than in group B. We conclude that reperfusion of infarct-related coronary artery changes serum CPK time-activity curve resulting in earlier appearance of peak serum CPK and that infarct size cannot be estimated by serum CPK level alone.