Dual-Imaging Stress Echocardiography for Prognostic Assessment of High-Risk Asymptomatic Patients with Diabetes Mellitus

Background: In patients with diabetes, the utility of diagnostic screening cardiac tests in subjects without clinical coronary artery disease remains controversial. The aim of this study was to assess the prognostic meaning of dual-imaging stress echocardiography (conventional wall motion analysis and Doppler-derived coronary flow velocity reserve [CFVR] of the left anterior descending coronary artery) in high-risk asymptomatic individuals with diabetes. Methods: This was a prospective analysis of 230 asymptomatic patients with diabetes (128 men; mean age, 66 6 9 years) with no clinical evidence of coronary artery disease, no Q waves or deep negative waves on the electrocardiogram, and no wall motion abnormalities on resting echocardiography. Of these subjects, 147 (64%) had target organ damage and 83 (36%) had two or more associated cardiovascular risk factors. All patients underwent dipyridamole stress echocardiography with CFVR assessment of the left anterior descending coronary artery by transthoracic Doppler, and test results were entered into a database at the time of testing for a clinical and outcome follow-up (mean, 4.6 +/- 2.7 years). Results: Inducible ischemia and reduced CFVR (<= 2) were detected in six and 52 patients, respectively. A total of 54 subjects (23%) had abnormal test results (ischemia or reduced CFVR). During follow-up, 39 major adverse cardiac events (MACEs) occurred: 22 hard events (18 deaths and four nonfatal myocardial infarctions) and 17 coronary revascularizations. The yearly incidence rates of hard events and MACEs in the entire study population were 2.1% and 3.6%, respectively. Abnormal test results were the only multivariate indicator of both hard events (hazard ratio, 3.69; 95% CI, 1.54-8.80) and MACEs (hazard ratio, 6.12; 95% CI, 3.22-11.62). Conclusions: Abnormal test results were obtained in one of four cases and were a strong and independent predictor of future hard events and MACEs.