Blood urea nitrogen to creatinine ratio is associated with congestion and mortality in heart failure patients with renal dysfunction

Renal dysfunction (RD) and venous congestion are related and common in heart failure (HF). Studies suggest that venous congestion may be the primary driver of RD in HF. In this study, we sought to investigate retrospectively the relationship between common measures of renal function with caval congestion and mortality among outpatients with HF and RD. We reviewed data from 103 HF outpatients (45 males, mean age 74 years, ejection fraction 41.8 ± 11.6 %) with estimated glomerular filtration rate (eGFR) of 25.5 (adjusted OR 2.98, p 0.015) and eGFR ≤45.8 (adjusted OR 5.38, p 0.002) identify patients at risk for caval congestion; a BUN/Cr >23.7 was the best predictor of impaired collapsibility (adjusted OR 4.41, p 0.001). a BUN/Cr >25.5 (HR 2.19, 95 % CI 1.21–3.94, p < 0.001) and NYHA class 3 (HR 2.91, 95 % CI 1.60–5.31, p < 0.0005) were independent risk factors associated with all-cause death during a median follow-up of 31 months. In outpatients with HF and RD, a higher BUN/Cr and lower eGFR are reliable renal biomarkers for caval congestion. The BUN/Cr is associated with long-term mortality and may help to stratify HF severity.