The diagnostic value of different enzymes and standard ECG in acute myocardial infarction.

Serum (S) enzyme activity of aspartate aminotransferase (ASAT, E.C. 2.6.1.1.), heat stable lactate dehydrogenase (LD, E.C. 1.1.1.27.), creatine kinase (CK, E.C. 2.7.3.2.) and CK-B subunit and the respective standard electrocardiograms (ECG) were compared in 463 patients with suspected acute myocardial infarction (MI) in order to evaluate sensitivity and specificity. Serum ASAT was analysed daily for 3 days, S-heat stable LD every 12 h for 48-108 h, S-CK and S-CK-B every 6 h for 48 h and ECG once daily for 3 days. All four enzymes had a high sensitivity, varying from 99% for LD to 97% for CK-B. The highest specificity was observed for CK-B and CK (98%) as compared with heat stable LD (91%) and ASAT (74%). Standard ECG showed a high specificity (96%) and a low sensitivity (80%).