Objective> Pulse wave velocity (PWV) or carotid intima-media thickness (IMT), an indicator of arterial stiffness, has been reported to be an independent predictor of coronary artery disease (CAD). This study aimed to investigate the usefulness of the circumferential strain and the distensibility of common carotid artery (CCA), the novel indicators of arterial stiffness, for the prediction of the concurrent CAD in comparison with PWV and carotid IMT. Methods> Thirty patients (CAD: non-CAD=15:15, age= 59짹10yrs) who underwent coronary angiography were enrolled. CAD was defined with stenosis of more than 50% in at least one major epicardial coronary artery. Carotid IMT as well as PWV (VP 1000, Colin Waveform analyzer) was obtained. Peak circumferential strain and distensibility of CCA were measured using 2D speckle tracking and M-mode images of CCA. Beta stiffness index I (BSI 1) and 2 (BSI 2) were calculated as the followings: BSI 1= (SBP/DBP)XDd/(Ds-Dd), BSI2 = (SBP/DBP)/Scirc (SBP, systolic blood pressure; DBP, diastolic blood pressure; Dd, diastolic diameter of CCA; Ds, systolic diameter of CCA; Scirc, circumferential strain of CCA) Results> The patients with CAD showed significantly higher BSI 1, BSI 2, carotid IMT, PWV than non-CAD patients (26.91짹10.01 vs. 18.79짹4.69, p<0.01 for BSI 1; 0.31짹0.13 vs. 0.17짹0.05, p<0.005 for BSI 2; 1.00짹0.23mm vs. 0.8짹0.11mm, p<0.05 for IMT; 1.63짹0.18m/s vs. 1.44짹0.28m/s, p<0.05 for PWV). Among those parameters, only BSI 2 and IMT had significant correlation each other (r=0.38, p<0.05). Receiver operating curve (ROC) analysis demonstrated the area under the curve (AUC) of BSI 2 was comparable to that of carotid IMT in predicting concurrent CAD (AUC = 0.869, 95%CI 0.743-0.995 for BSI 2; AUC = 0.767, 95%CI 0.592-0.942 for IMT). Each cut-off values of BSI 2 and IMT for prediction of concurrent CAD were 20.65 and 0.95mm (sensitivity 87%, specificity 80% for BSI 2; sensitivity 60X%, specificity 93% for IMT). Conclusion> BSI 2, an index for carotid arterial circumferential strain, rather than BSI 1 of an index for its distensibility, were closely associated with concurrent CAD. BSI 2 may be a useful alternative index to carotid IMT in determining the presence of concurrent CAD with comparable predictability.