Non-cardiac creatine kinase-B activity in serum after abdominal aortic bypass surgery.

Serum creatine kinase (CK) and creatine kinase isoenzyme MB (CK-B) were measured and electrocardiogram (ECG) recorded preoperatively and 24, 48 and 72 hours and 7 days after abdominal aortic bypass grafting in ten patients. No ECG abnormality indicating acute myocardial infarction (AMI) appeared and no patient had chest pain. CK-B was below the discrimination value for AMI in all cases preoperatively, but increased significantly after the operation to a maximal median value of 15 (range 5-32) U/l at 48 hours. The time-activity curve of CK paralleled that of CK-B, reaching a maximal median value of 814 (range 289-1972) U/l at 48 hours. On day 7 CK and CK-B had normalized. The CK-B activity relative to CK activity remained below 6% in all patients. Elevated serum CK-B activity should be utilized with caution for the diagnosis of perioperative AMI in patients undergoing aortic bypass grafting.