Renal Resistive Index as An Indicator of Atherosclerotic Changes and Renal Damage in Hypertension and Its Role in Therapeutic Intervention

Abstract

Background: Renal resistive index (RRI) was suggested as an indicator of renal atherosclerotic changes in hypertensive patients with possible prognostic role in treatment. Objectives: This study aimed to assess RRI in hypertensive subjects, its relation to other predictors of target organ damage and prognostic usefulness in management, specifically, with different antihypertensive drugs. Patients and methods: The study included 100 newly diagnosed hypertensive adult subjects, who underwent abdominal ultrasound with Doppler to assess RRI, which was correlated with their clinical parameters including estimated glomerular filtration rate (eGFR) and other subclinical atherosclerosis markers as carotid intima-media thickness (IMT) and aortic knob width (AKW) calculated from chest radiograph. Another 50 non hypertensive subjects were assessed for their RRI as a control group. In addition, some of hypertensive patients were followed up one year after starting treatment was done and effects of different antihypertensive agents on their RRI were compared. Results: The mean baseline RRI in hypertensive patients (0.71 ± 0.04) was significantly higher compared to control group (0.60 ± 0.02) and was positively significantly correlated with their clinical parameters (age, systolic, diastolic, pulse pressure and eGFR) and with their atherosclerotic parameters (IMT and AKW). In addition, ACE/ARBs treatment was associated with significant decrease of RRI compared to other drugs [beta blocker (BB) and calcium channel blocker (CCB)], indicating their more renal protective effect. Conclusion: Assessment of RRI in patients with primary hypertension not only reflecting intrarenal perfusion changes, but it indicates systemic atherosclerotic changes, so it can be useful as prognostic parameter in addition to its possible therapeutic implications.