Dobutamine stress echocardiography and troponin T as a marker of myocardial injury

Introduction and objectives. Troponin T (TnT) is a very specific marker of myocardial damage. Our objective was to describe TnT behavior after dobutamine stress echocardiography (EDOB) and evaluate its usefulness for improving the diagnostic power of EDOB. Methods. Blood levels of TnT were measured at baseline and 3, 6, 12, and 24 h after EDOB in 63 patients (mean age: 69 +/- 9; 38 males). Coronary angiography was performed on 36 patients. Results. EDOB was positive in 29 patients and there was an increase over baseline values in 15 of them (51%); EDOB was negative in 34 patients and there was only a rise in TnT in 7 (20%; p < 0.01). The TnT increment was higher in patients with a positive response to EDOB (0.033 +/- 0.02 vs. 0.026 +/- 0.01; p < 0.01). The ischemia score index was higher in patients in which a significant increase in TnT values was later detected (0.41 +/- 0.31 vs. 0.38 +/- 0.20; p < 0.01). Coronariography was performed in 36 patients. EDOB was positive in 22 of the 29 patients with coronary artery disease (76%) and TnT was raised in 14 of them (48%; p < 0.05). Conclusion. The rise in TnT levels during EDOB suggests that this test may produce myocardial damage associated with the appearance of contractility disorders during dobutamine infusion.