Renal Dysfunction in Heart Failure Is Due to Congestion but Not Low Output

Background: Renal dysfunction in heart failure is thought to be due to poor perfusion of the kidney. Hypothesis: We tested the hypothesis that passive congestion is more important than poor perfusion. Methods: We retrospectively studied the data on 178 patients who underwent right heart catheterization for evaluation of heart failure and had serum creatinine (Cr) measured on the same day. Results: Serum Cr and glomerular filtration rate (GFR) correlated with central venous pressure (r = 0.22, P = 0.001 and r = -0.55, P < 0.0001, respectively) and renal perfusion pressure (r = 0.21, P = 0.001 and r = 0.27, P = 0.015, respectively). Neither correlated with cardiac index or left ventricular ejection fraction. Serum Cr was significantly higher and GFR was significantly lower in the upper tertile of central venous pressure, pulmonary capillary wedge pressure as well as in the lower tertile of renal perfusion pressure. Conclusions: Renal dysfunction in heart failure is determined more by passive congestion than by low perfusion.