Clinical role of intrarenal venous flow patterns in decompensated heart failure with worsening renal function

Abstract

Introduction: The clinical implication of intrarenal venous flow patterns in decompensated heart failure with worsening renal function is unknown. We aimed to study the relationship between intrarenal venous flow patterns, inferior vena cava volume status, caval index, clinical degree of congestion and the renal outcome in patients with decompensated heart failure and worsening renal function. Secondary objectives were to study the combined endpoint of readmission and mortality rate within 30 days (after the last scan) among intrarenal venous flow patterns and the effect of congestion status on the renal outcome. Methods: Twenty-three patients admitted for decompensated heart failure (ejection fraction ⩽40%) with worsening renal function (absolute increase in serum creatinine of 26.5 µmol/L or ⩾1.5-fold increment from baseline) were enrolled in this study. A total of 64 scans were performed. Patients were visited on day 0, 2, 4 and 7 (or earlier if discharged). Patients were called 30 days after discharge to evaluate readmission or mortality. Intrarenal venous flow patterns were ranked from continuous, interrupted, biphasic, to monophasic. Clinical congestion was scored from 0 to 7. Results: Intrarenal venous flow patterns had statistically significant positive correlations with inferior vena cava volume status (Spearman’s ρ, 0.51; p < 0.01) and congestion score ( ρ, 0.65; p < 0.01) and a significant negative correlation with caval index ( ρ, −0.53; p < 0.01). Intrarenal venous flow patterns were not significant in predicting estimated glomerular filtration rate improvement or the combined endpoint. Reduced congestion significantly predicted an estimated glomerular filtration rate improvement on the following scan day ( p = 0.04, odds ratio = 4.3, 95% confidence interval = 1.1–17.2). Conclusion: Although intrarenal venous flow patterns correlate with other congestive parameters, clinical congestion status rather than intrarenal venous flow patterns predicted the renal outcome.