Stress echocardiography for risk stratification of diabetic patients with known or suspected coronary artery disease

OBJECTIVE - Coronary artery disease (CAD) is a leading cause of mortality a nd morbidity in diabetic patients; therefore, their risk stratification is a relevant issue. Because exercise tolerance is frequently impaired in thes e patients, pharmacological stress echocardiography (SE) has I been suggest ed as a valuable alternative. Our aim was to evaluate the prognostic value of this technique in diabetic patients with known or suspected CAD. RESEARCH DESIGN AND METHODS - A total of 259 consecutive diabetic patients underwent pharmacological SE (dobutamine in 108 patients and dipyridamole i n 151 patients) and follow-up for 24 +/- 22 months. A comparison between th e prognostic value of SE and exercise electrocardiography (ECG) was made in a subgroup of 120 subjects. RESULTS - A total of 13 cardiac deaths and 13 nonfatal infarctions occurred during follow-up, and 58 patients were revascularized. Univariate predicto rs of outcome were known CAD, positive SE, rest and peak wall motion score index (WMSI), and peak/rest WMSI variation. Peak WMSI was the only signific ant and independent prognostic indicator (odds ratio 11; 95% Cl 4-29, P < 0 .0001) on multivariate Cox's analysis, After adjustment for the most predic tive clinical and exercise ECG variables, SE provided 43% additional progno stic information (gain in X-2 = 7. P < 0.01). Moreover, positive SE was ass ociated With a significantly lower event-free survival. CONCLUSIONS - SE effectively predicts cardiac events in diabetic patients w ith known or suspected CAD and adds additional prognostic information as co mpared with exercise ECG.