Cardiac troponin-T and the prediction of acute and long-term mortality after acute pulmonary embolism

Background: Although cardiac troponin elevation during acute pulmonary embolism (PE) predicts in-hospital death, its long-term prognostic significance, and the role of troponin-T concentration in this prediction, is unknown. Moreover, its use in acute PE in elderly populations with multiple comorbidities is not well described. Methods: Consecutive patients presenting with confirmed PE to a tertiary hospital between 2000 and 2007 with troponin-T measured were identified retrospectively and their outcomes tracked from a state-wide death registry. Results: There were 577 patients, (47% male) with a mean age (± standard deviation) of 70.1 ± 15.2 years, of whom 19 died during index admission. Of the 558 patients who survived to discharge, 186 patients died during a mean follow-up of 3.8 ± 2.4 years. There were 187 (32%) patients with elevated troponin-T (≥ 0.01 μg/L). Troponin-T concentration was significantly and independently associated with in-hospital and long-term mortality whether analyzed as a continuous or categorical variable (p < 0.001). However, different cut-points were required to optimally predict in-hospital and post-discharge long-term mortality in multivariate analysis. Troponin-T ≥ 0.01 μg/L was not an independent predictor of in-hospital or post-discharge survival. A cut-point of troponin-T ≥ 0.03 μg/L was required to independently predict in-hospital death (p = 0.03), and troponin-T ≥ 0.1 μg/L was required to independently predict long-term mortality (hazard ratio 2.3, 95% confidence interval 1.4-3.8, p = 0.001). Conclusions: Troponin-T elevation during acute PE shows a concentration-dependent relationship with acute and long-term outcome. Concentrations of troponin-T well above the threshold for detection may be required to independently contribute to prediction of outcome in elderly populations with acute PE.