Detection of coronary artery disease in asymptomatic patients with type 2 diabetes mellitus

OBJECTIVES We sought to verify the effectiveness of current American Diabetes Association screening guidelines in identifying asymptomatic patients with coronary artery disease (CAD) in type 2 diabetes mellitus (DM2). BACKGROUND In DM2 patients, CAD generally is detected in an advanced stage with an extensive atherosclerosis and poor outcome, whereas CAD in an asymptomatic stage is commonly missed. METHODS This study, included 1,899 asymptomatic DM2 patients (age <= 60 years). Of these, 1,121 had >= 2 associated risk factors (RFs), group A, and the remaining 778 had <= 1 RF, group B, for CAD. All patients underwent dipyridamole myocardial contrast echocardiography (MCE), and in those with myocardial perfusion defects, the anatomy of coronary vessels was analyzed by selective coronary angiography. RESULTS In the two study groups, the prevalence of abnormal NICE (59.4% vs. 60%, p = 0.96) and of a significant CAD (64.6% vs. 65.5%, p = 0.92) was similar, irrespective of RF profile. But coronary anatomy differed: group B had a lower prevalence of three-vessel disease (7.6% vs. 33.3%, p < 0.001), of diffuse disease (18.0% vs. 54.9%, p < 0.001), and of vessel occlusion (3.8% vs. 31.2%, p < 0.001), whereas one-vessel disease was more frequent (70.6% vs. 46.3%, p < 0.001). Coronary anatomy did not allow any revascularization procedure in 45% of group A patients. CONCLUSIONS An aggressive diagnostic approach, requiring coronary angiography in asymptomatic DM2 patients with <= 1 associated RF for CAD and abnormal MCE, identified patients with a subclinical CAD characterized by a more favorable angiographic anatomy. The criterion of <= 2 RFs did not help to identify asymptomatic patients with a higher prevalence of CAD and is only related to a more severe CAD with unfavorable coronary anatomy.