Predicting microvascular obstruction with cardiac troponin T after acute myocardial infarction: a correlative study with contrast-enhanced magnetic resonance imaging

The presence of microvascular obstruction (MVO) is associated with more severely impaired left ventricular function and adverse prognosis. The aim of this study was to evaluate whether a single cardiac troponin T-value (cTnT) was able to predict the presence of MVO and whether cTnT is an independent predictor of MVO as compared to usual risk factors. Sixty-one consecutive patients with reperfused ST-elevation myocardial infarction (STEMI) were enrolled in the study. cTnT was measured serially at admission and after 24, 48, 72 and 96 h. Contrast-enhanced cardiac magnetic resonance imaging (CE-MRI) was performed on a 1.5T MR-scanner 4 +/- A 1 days after STEMI. cTnT-time concentration kinetics in the presence of MVO differs from cTnT release in the absence of MVO showing a higher peak and a slower release. At single point measurement 24 h-cTnT correlates at least as well with the presence of MVO (P < 0.001) as peak cTnT (P = 0.0016) and sampling over 96 h (P < 0.001). Using ROC analysis, at single measurement a cTnT concentration > 2.52 mu g/l at 24 h was a predictor for MVO (AUC 0.91) with a sensitivity of 100% and a specificity of 80% with a positive predictive value of 76% and a negative predictive value of 100%. In multivariate regression analysis 24 h-cTnT remained independent predictor for MVO. In STEMI, a single 24 h-cTnT value is an independent predictor for MVO and a convenient and inexpensive way to help define this important risk parameter in clinically routine.