Abstract
We have studied the changes in creatine kinase (CK) and creatine kinase MB (CK-MB) activity and concentration for the diagnosis of acute myocardial infarction in 73 patients admitted to the coronary care unit with cardiac symptoms of 12 h duration or less. Serial blood samples were obtained for an 8 h period following admission and CK, CK-MB activity and concentration measured. We compared the performance of single values at optimized diagnostic cut-offs and incremental change (log slope) for all three measurements. CK slope combined with CK-MB concentration measurements allowed accurate diagnosis at 4 h from admision. CK-MB concentration determination 8 h from admission (12–16 h from the onset of chest pain) was the most efficient single measurement. Rapid diagnostic categorization and possible selection of patients for thrombolysis in patients with an uncertain admission diagnosis is possible by these techniques.