Creatine Kinase MB Isoforms in Patients with Skeletal Muscle Injury: Ramifications for Early Detection of Acute Myocardial Infarction

202 serum and plasma samples from nine groups: 39 with acute myocardial infarction (MI), 26 with chest pain (MI ruled out), 17 undergoing bypass surgery or cardiac catheterization, 17 with acute skeletal muscle injury, 30 marathon runners immediately after a race, 17 runners and other athletes > 12 h after training or a race, 12 with cerebral injury or seizures, 8 with closed head injury, and 38 normal subjects.

Measurement of total creatine kinase (CK), CK-MB isoenzyme, and MB isoforms (MB2/MB1)

Comparison across different patient groups (MI, skeletal muscle injury, normal subjects, etc.)

Levels of CK-MB (relative index) and MB isoforms (MB2/MB1 ratio)surrogate