Renal arterial resistance index: a marker of renal dysfunction with an incremental role in predicting heart failure progression

Abstract

The aim of this study was to evaluate in a group of chronic heart failure (CHF) outpatients whether a parameter reflecting renal perfusion (Renal Resistance Index, RRI) could add an incremental prognostic information to the standard evaluation of renal dysfunction. We enrolled 250 outpatients (78% males, 64±13 years, NYHA class 2.2±0.6, left ventricular ejection fraction, LVEF, 34±10%) with CHF (ESC criteria) due to left ventricular systolic dysfunction, in stable clinical conditions (> 1 month) and in conventional therapy. Peak systolic velocity and end diastolic velocity of segmental renal artery was obtained by pulsed Doppler flow and RRI was then calculated. Standard renal function assessment was obtained by measurement of creatinine serum levels and the calculation of glomerulare filtration rate by MDRD formula. During follow-up (17.8±9.9 months), 37 patients experienced heart failure progression (hospitalization and/or heart transplantation and/or death due to heart failure worsening). As shown in part A of the figure, when the presence of RRI >75% was added to a Cox multivariate regression model including age >65 years, NYHA class III, LVEF 1500 pg/ml and GFR 75 was associated to a worse prognosis both in patients with preserved and impaired renal function. ![Figure][1] Figure 1 In conclusion, our findings demonstrate the possible clinical uselfuness of a parameter reflecting renal perfusion in order to better characterise cardiorenal syndrome and to better stratify patients' prognosis. [1]: pending:yes