Abstract
CPK-MM, one of the CPK-isozyme, is divided into the three subbands (isoform) MMa, MMb, MMc. It has reported that in acute myocardial infarction serum MMa and MMa/MMc increased earlier than other myocardial intracellular enzyme, such as CPK-MB. In this study, we measured serum CPK, CPK isozyme, and CPK isoforms during and after open heart surgery and examined whether CPK isoforms would serve as a marker for myocardial damage during open heart surgery. CPK-MB peaked at 153.3±85.1IU six hours after cardiopulmonary bypass (CPB) was taken off and subsequently decreased. On the other hand, MMa/MMc peaked at 5.6±2.2 immediately after CPB was taken off. Moreover, we found that there was a statistically significant positive correlation (Y=24.46X+16.68, r=0.63, p<0.05) between MMa/MMc immediately after CPB was taken off and CPK-MB six hours after CPB was taken off. The maximum value of CPK-MB correlates with the degree of myocardial damage. Therfore, it is reasonable to suggest that the maximum value of MMa/MMc immediately after CPB is taken off also correlates with the degree of myocardial damage. We concluded that serum CPK isoform, especially MMa/MMc served as a marker to estimates the degree of myocardial damage in open heart surgery at an early stage.
