Background and Purpose-The intima-media thickness (IMT) of the common carotid artery (CCA) is well correlated with the degree of arteriosclerosis and is a predictor of cardiovascular morbidity and mortality. The (hemodynamic) resistive index (RI) of the internal carotid artery (ICA) correlates with the degree of arteriosclerosis just as well as IMT. The aim of the study was to compare the predictive values of RI and IMT with regard to cardiovascular morbidity and mortality. Methods-A total of 146 patients with cardiovascular risk factors or established arteriosclerosis were included. Duplex sonography of the CCA and ICA was performed, and the IMT and RI were measured in both vessels. During follow-up for a median of 36 months, the occurrence of cardiovascular events (myocardial infarction, stroke, or cardiovascular death) was assessed.

Our results confirm the predictive value for cardiovascular events of RI and IMT in long-term follow-up. In contrast to RI, IMT increases over six years, above all in patients suffering a cardiovascular event. The results suggest that IMT is suitable for cardiovascular risk prediction as well as for progression measurements, while RI cannot be recommended for progression measurements. The effect of drug therapy on RI needs further clarification.

PROCAM-, FRAMINGHAM- and SCORE-risk score seem to be barely useful in a secondary prevention setting. In patients with overt atherosclerosis, the cardiovascular risk seems to be better assessed by means of the SMART score.