Evaluation of Creatine Phosphokinase Isoenzyme Activity in Acute Myocardial Infarction

抄録

This study was performed to clarify the relationship between diagnosis of acuti myocardial infarction (AMl) and level of creatine phosphokinase (CPK) activity. We studied a patient with AMl (case preserltation). ln order to obtain the time course of CPK activity, the serial serum samples were assayed for the total CPK and for one of its isoenzymes, CPKMB.Six hours after the admission, the ratio of CPK-MB to total CPK was 18% and after 1 week, it returned to normal range. Seven weeks later the patient was discharged.
We next discussed the serum level of CPK-MB in AMl group (18 patients) and in non-AMl group (41 patients). The value of CPK-MB/total CPK in AMl was 2.5 fold compared with non-AMl within 24 hours and 2.2 fold within 24 to 48 hours after theadmission. We lastly investigated the relationship between the elapsed time after chest pain and the level of CPK activity.The CPK-MB activity diagnostically increased within 2 hours following onset of chest pain and markedly within 6 to 12 hours.The elevated level of more than 7% of CPK-MB/total CPK correlated well with diagnosis of AMl.
From these results, it has been definitely shown that subjects can bediagnosed as AMl in an early phase by the determination of CPK-MB in serum.