The release of cardiac specific serum enzymes as an index for the evaluation of myocardial protection with cold blood and crystalloid cardioplegia

摘要

Myocardial protection during open heart surgery was studied in 52 patients with complex congenital heart disease. Twenty-six patients received b1ood cardioplegia (BCP) and 26 crystalloid cardioplegia (CCP). Release of serum enzymes (creatine kinase, CK; hybrid muscle-brain CK isoenzyme, CK-MB; aspartate aminotransferase, ASTF and 1actic dehydrogenase, LDH) was determined pre-and post-operatively. DUring the first 72 h post-operation, release of CK, CK-MB, AST and LDH in the 2 groups was different, In case of tetralogy of Fallot (TOF) the CK-MB released in l3CP and CCP 12 h after operation were 51. 29±9. 42 and 85. 77±22. 39 U/L respectively (P<0. 05). In the CCP group of TOF, CK-MB level increased significantly even at 72 h after operation (30. 91±14. 32 U/L vs the pre-operative value of 14. 57±7. 51 U/L). The results show a better myocardial preservation in the BCP group as compared with the CCP group. BCP can maintain metabolic homeostasis of the myocardium, reduce myocardial injury and increase the content of myocardial high energy phosphate during ischemia. Tolerance to ischemia is poor in patients with complex congenital heart disease. Therefore, preservation of high energy phosphates is necessary for severe-grade patients and BCP is superior to crysta1loid cardioplegia in this regard. It is concluded that CCP results in a higher release of CK-MB as compared with BCP group. BCP is superior to CCP for myocardial protection in patients with complex congenital heart disease.