Prognostic value of troponin T, myoglobin, and CK-MB mass in patients presenting with chest pain without acute myocardial infarction

Objective-To assess the prognostic value of minor myocardial damage in patients presenting with chest pain without myocardial infarction. Design-The relative risk of suffering a cardiac event in the next six months was assessed in patients with minor myocardial damage assessed by the cardiac markers CK-MB, myoglobin, and troponin T. Setting-Emergency department of a large university hospital. Patients-In 128 consecutive patients with chest pain, acute myocardial infarction (by WHO criteria) was ruled out; of these, 39 had a rise and fall of one or more markers, indicating minor myocardial damage. The presence of a documented history of coronary artery disease was assessed on admission. Results-24 patients had a event (cardiac death, acute infarction, percutaneous transluminal coronary angioplasty, coronary artery bypass grafting) in the next six months. An abnormal troponin T predicted a subsequent event while abnormal CK-MB or myoglobin did not. The relative risk for troponin T was 2.8 (95% confidence interval: 1.0 to 7.9), for myoglobin 1.0 (0.3 to 3.2), and for CK-MB 0.9 (0.2 to 3.4). A documented history of coronary artery disease predicted subsequent events with a relative risk of 3.9 (1.3 to 11.3). Conclusions-Troponin T was the only marker that predicted future events, but a documented history of coronary artery disease was the best predictor in patients in whom an acute myocardial infarction had been ruled out.