[Analyses of creatine kinase isoforms to detect early diagnosis of reinfarction and reperfusion after acute myocardial infarction].

The detection of reinfarction and reperfusion of the acute myocardial infarction (AMI) in the early phase was studied by monitoring the 34 AMI patients of their changes in creatine kinase (CK, EC 2.7.3.2) isoforms level. CK isoform was assayed by immunoinhibition method using monoclonal antibody. The increased ratio of serum CK-MM3/CK-MM1 after the onset was observed earlier than conventional serum parameters such as CK-MB, CK-MM3, PK and LD and it was almost the same as myoglobin in both reperfused and non-reperfused patients. The increased ratio of CK-MM3/CK-MM1 in reperfusion group was gradually reduced after 5 hours of onset earlier and lowered to reference level two to three times more rapidly than in non-reperfusion group. The ratio of serum CK-MM3/CK-MM1 with AMI increased much more sharply compared to that of after hard exercise. Therefore, monitoring the ratio of patients serum CK-MM3/CK-MM1 with AMI (at serial times, or periodically, or every 3 hours, etc.) is significant for clinical diagnosis.