Characteristics of creatine release during acute myocardial infarction, unstable angina, and cardiac surgery.

Creatine release was compared in various conditions of muscle damage: acute myocardial infarction (AMI), unstable angina, and cardiac surgery. After AMI, serum and urine creatine concentrations increased transiently. After cardiopulmonary resuscitation, serum creatine values were significantly higher because of impaired renal function, whereas urinary creatine concentrations were comparable. In 38 patients with unstable angina, no significant changes in serum and urine creatine concentrations were seen. In 37 of 92 AMI patients, secondary creatine peaks were observed 20.9 +/- 8.1 h after onset of symptoms. The magnitudes of the first and second peaks were correlated: Spearman r = 0.66. In 24 patients who underwent cardiac surgery, the changes in creatine concentration in serum during surgery were very small, despite the presence of muscle trauma.