Troponin T concentration 3 days after acute ST-elevation myocardial infarction predicts infarct size and cardiac function at 3 months.

OBJECTIVES

The evaluation of infarct size and left ventricular function after acute myocardial infarction is important for predicting the subsequent clinical course. This assessment can be achieved by non-invasive imaging methods, but biochemical assays are frequently used as an alternative. We investigated the ability of a single measurement of cardiac troponin T (cTnT) the third morning after onset of ST-segment elevation myocardial infarction (STEMI) to predict infarct size and left ventricular ejection fraction (LVEF).

METHODS

The study population consisted of 103 patients with their first STEMI treated with thrombolysis. Blood samples for determination of cTnT were drawn the third morning after onset of symptoms. Infarct size and LVEF were assessed by magnetic resonance imaging 3 months later.

RESULTS

Linear regression analysis showed a strong, significant correlation between third-day cTnT and infarct size at 3 months (r = 0.84, p < 0.0001). A significant but inverse and weaker correlation was obtained between third-day cTnT and LVEF (r = -0.63, p < 0.0001). Adjusting for age, gender, infarct location and medication changed the results marginally.

CONCLUSIONS

A single cTnT value the third morning after onset of STEMI predicted the final infarct size in this group of patients with their first STEMI, and might be useful for ruling out impaired LVEF.