Diagnostic value of cardiac multi-detector computed tomography for detection of subclinical atherosclerosis in asymptomatic diabetic patients

Abstract

Purpose: Silent myocardial ischemia in asymptomatic subjects with no history of ischemic heart disease is a frequent condition in diabetic patients. Therefore the detection of subclinical atherosclerosis in asymptomatic diabetic patients is important. The aim of the present study was to investigate the prevalence, characteristics, and prognostic value of coronary 64-slice multi-detector computed tomography (MDCT) in asymptomatic diabetic patients. Methods: We retrospectively enrolled self-referred 444 diabetic patients (age = 58.2±8.3 years, 326 males) who underwent both coronary MDCT angiography and coronary calcium scoring from January 2008 to June 2011. For all subjects, we evaluated clinical risk factors and investigated cardiac events. Subclinical atherosclerosis was defined as the any detectable plaques on MDCT and significant stenosis was defined as more than 75% narrowing of coronary artery diameter in this study. Results: Subclinical atherosclerosis was found in 214 subjects (48.2%). The subclinical atherosclerosis group was older, more patients with male, smokers, high level of fasting serum glucose. Independent predictors of subclinical atherosclerosis were old age (≥ 65years) [odds ratio (OR): 1.099, 95% confidence interval (CI): 1.01-1.19, p=0.022], and high level of HbA1C (≥ 7.0%) (HR: 1.64, 95% CI: 1.02-2.66, p=0.042) in multivariate logistic regression analysis. And significant coronary stenosis in MDCT was found in 83 patients (18.7%). The significant stenosis group was older, more patients with hypertension, smokers, high level of high sensitivity C-reactive protein (hs-CRP). High level of hs-CRP high (≥ 2mg/L) was an independent predictor of significant stenosis (OR: 2.66, 95% CI: 1.67-4.02, p=0.012). 71 patients who showed significant stenosis underwent stress test, such as treadmill exercise test or myocardial SPECT. Among them, 48 patients underwent conventional coronary angiogram and 20 patients underwent percutaneous coronary intervention. During clinical follow-up (mean follow-up period=21.5±11.3 months), of all subjects myocardial infarction was developed in 3, unstable angina in 17, target lesion revascularization in 4 patients. Conclusions: In this study, the prevalence of subclinical coronary atherosclerosis in asymptomatic diabetic patients was nearly fifty percent. Cardiac MDCT will be an useful method for detection of subclinical atherosclerosis in diabetic patients.