Ischemia-dependent Elevation of Creatine Phosphokinase Myocardial Isoenzyme and Additive Effects to the Diagnostics of Exercise Testing

Myocardial isoenzyme of creatine phosphokinase (CKMB) has been demonstrated to rise slightly due to myocardial ischemia without necrosis. In our study, it was aimed to scrutinize this claim and to search whether there were or not additive effects to the diagnostics of exercise testing. For this purpose, 42 cases whose exercise test results for ischemia had been diagnosed as positive were studied before performing their coronary angiographies. The difference of CK-MB values (D CKMB), that was obtained just before testing and 6 hours latter, in the group of 32 cases (52±7 age, 25 male and 7 female) who had critical lesions on their coronary angiograms, were compared with those of 10 cases (42±7 age -p>0.3-, 9 male, 1 female) with normal coronary arteries (7.61±5.5, 1.75±2.3, p<0.001). In view of the shorter exercising periods of the first group (7.24±2.2 vs 9.53±2.3 minutes, p<0.02), it is likely that the significant difference was due to ischemia. By means of ? CKMB related results, a 60 % specificity and 84 % sensitivity have been obtained. These findings suggest that D CKMB of the sixth hour may be of additive value for the diagnostics of exercise testing.