Long-term changes in renal function and perfusion in heart failure patients with reduced ejection fraction

Little is known about the natural course of renal function and renal hemodynamics in heart failure patients with reduced ejection fraction (HFREF).

We prospectively studied effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) in 73 HFREF patients with ¹²⁵I-iothalamate/¹³¹I-hippuran clearances with a mean follow-up of 34.6 ± 4.4 months. Fifteen percent were female, with age 58 ± 12 years and left ventricular ejection fraction (LVEF) 29 ± 10 %. Baseline GFR was 81 ± 23 mL/min/1.73 m² and declined 0.6 ± 4.7 mL/min/1.73 m² per year. Baseline ERPF was 292 ± 83 mL/min/1.73 m² and declined 4.3 ± 19 mL/min/1.73 m² per year. Of the baseline variables, older age and high urinary kidney injury molecule-1 were the only variables associated with GFR decline (p < 0.05). Following stepwise backward analysis, only age (p < 0.001) remained significant. In addition, we found an association between change in GFR and changes in ERPF, N-terminal pro-brain natriuretic peptide and renovascular resistance. In the multivariable analysis, only the change in ERPF remained significantly associated with a change in GFR (p < 0.001).

In this cohort of stable chronic HFREF patients, the average decline in GFR over time was small. The decline of GFR was associated with a higher age and a lower baseline GFR, and was strongly related to changes in renal perfusion.