Creatine kinase release not associated with myocardial necrosis after short periods of coronary artery occlusion in conscious baboons

The effects of 15 minute periods of coronary artery occlusion on plasma creatine kinase (CK) and CK-MB isoenzyme activity, regional myocardial function and subsequent myocardial necrosis were studied in six conscious baboons 2 to 3 weeks after recovery from instrumentation. Mid left anterior descending coronary artery occlusion induced complete loss of systolic wall thickening (ultrasound transit time technique) and decreases in epicardial (-93%) and endocardial (-96%) blood flows (microsphere technique). Reperfusion after 15 minutes resulted in complete recovery of regional function 24 hours later. Serial plasma enzyme activity revealed a significant increase in total CK from 71 ± 11 to 976 ± 158 U/liter and in CK-MB from levels that were too low to measure to 21.4 ± 2.9 U/liter. At autopsy, neither gross pathologic evidence (triphenyltetrazolium chloride staining technique) nor histologic evidence of myocardial necrosis was observed. Thus, in the conscious baboon short episodes of myocardial ischemia are associated with a significant appearance of CK and CK-MB in the blood in the absence of cellular necrosis.