OBJECTIVE Coronary artery disease (CAD) is a major cause of heart failure associated with left ventricular systolic dysfunction (LVSD). The prognosis of LVSD is significantly influenced by the etiology of heart failure and therefore, differentiation of significant CAD from other etiologies is important. Carotid intima-media thickness (IMT) and plaque are useful predictors for cardiovascular events, including stroke and CAD. The purpose of this study was to evaluate the predictive value of carotid IMT and plaque for the diagnosis of CAD in LVSD patients. METHODS Seventy-three (n= 73, 47 male, 67.6±12.4 years) patients hospitalized for heart failure with severe LVSD were retrospectively enrolled. The severity of CAD was analyzed by the Duke Jeopardy Score system, and carotid IMT and plaque were measured according to the Mannheim Carotid IMT Consensus. RESULTS Significant CAD was found in 41 patients (56.1%, CAD group) on coronary angiography. Mean common carotid artery (CCA) IMT (0.74±0.05 mm vs. 1.04±0.04 mm, p<0.01) was significantly higher in the CAD group. Plaque in CCA (6.25% vs. 19.5%, p<0.01) and plaque in bulb (25.0% vs. 60.9%, p<0.001) were significantly higher in the CAD group. Mean CCA IMT {odds ratio (OR) 2.61, 95% confidence interval (CI) 1.134-4.469, p<0.01} and plaque in bulb (OR 4.69, 95% CI 1.702-12.965, p<0.01) were significant predictors for the diagnosis of CAD according to multivariate logistic regression analysis. CONCLUSIONS In patients with severe LVSD, mean CCA IMT and bulb plaque can be useful additional predictors for the diagnosis of CAD.