Background: In the past few years, there has been growing attention to markers of subclinical organ damage because they are able to provide an accurate prediction of global cardiovascular outcome. The renal resistive index (RRI) measured using Doppler ultrasonography has been used as a diagnostic tool in the daily work-up of cardiovascular diseases. A better understanding of its relationship with preclinical organ damage may help in determining overall cardiovascular risk in hypertensive patients. The variability of RRI in hypertensive patients and the usefulness of the marker and interpretational difficulties of the index are an important matter of concern, which should not be underestimated in the course of diagnosis and management of cardiovascular diseases. This review summarizes current concepts in RRI interpretation against the cardiovascular pathologies, focusing on the vascular damage association with regard to the complex nature of RRI value variability. Currently, RRI measured in intrarenal segmental arteries is a well-known marker of renal vascular and interstitial damage, corresponding to an increased total cardiovascular risk. Conclusions: RRI has been shown to be a marker of renal and extrarenal organ damage in arterial hypertension. Several studies indicate that this index may in part reflect systemic vascular stiffness and entail a worse cardiovascular prognosis. On the basis of these results, the evaluation of RRI should be used to complement other signs of target organ damage in the assessment and management of hypertensive patients. Therefore under specific conditions, RRI could be considered as a renal vascular damage index.