[Uselessness of high-sensitivity cardiac troponins to improve diagnostic accuracy of dobutamine stress echocardiography in high-risk diabetic patients]

Abstract

Background and aim: Dobutamine stress echocardiography (DSE) is a well-established noninvasive stress modality for the detection and evaluation of coronary artery disease in diabetic patients. High-sensitivity cardiac troponin T recently emerged as a highly sensitive dosage for the detection of ischemia. The aim of the study was to examine whether high-sensitivity cardiac troponin T may improve the diagnostic accuracy of silent ischemia by DSE in high-risk diabetic patients.

Methods and results: Twenty-one patients with long-standing (>10years) and/or complicated type II DM but no established CAD were included. In addition to DSE, venous blood samples for measurement of hs-cTnT were collected prior to DSE, 6hours and 24hours after the test. Troponins were deemed positive if>1.5 upper limit for normality. Patients with positive troponins underwent coronary angiography or CT scan regardless of the result of DSE. Among the 21 patients, 7 had positive troponins measured 6hours after stress, (mean peak troponin=44.5). DSE were negative in all of them. Mean age was 64years significantly higher than patients with negative troponins. No differences were noted between the groups in terms of epidemiological, clinical or echocardiographic characteristics. Patients with positive cardiac troponins were evaluated for the presence of coronary lesions but none of them had significant disease. After an 18-month mean follow-up, no adverse cardiac events were noted in either group.

Conclusion: In high-risk diabetic patients, the measurement of hs-cTnT during DSE does not improve the sensitivity at least in those with negative DSE tests.

Keywords: Diabetes mellitus; Diabète; Dobutamine stress echocardiography; Hypersensitive cardiac troponins; Troponines hypersensibles; Échocardiographie de stress à la dobutamine.