Impaired renal blood perfusion is closely related to right heart volume overload in congestive heart failure

BACKGROUND: This study investigated the impact of right heart volume overload on renal perfusion in patients with heart failure (HF). We retrospectively analyzed 304 ambulatory HF patients enrolled between October 2017 and August 2022. Echocardiographic parameters-including left atrial diameter (LAD), left ventricular end-diastolic diameter (LVEDD), right atrial diameter (RAD), right ventricular diameter (RVD), and left ventricular ejection fraction (LVEF)-were measured and adjusted for body surface area (BSA). Renal perfusion was assessed via time-to-peak of renal blood flow (TTPr) using renal scintigraphy. Relationships between echocardiographic measures and TTPr were evaluated using Spearman correlation and multivariable ordinal logistic regression analyses. RESULTS: In the overall cohort, RAD/BSA showed the strongest correlation with TTPr (rs = 0.608, P < 0.001), which remained significant after multivariable adjustment. LVEDD/BSA and LVEF showed weak or no associations. Subgroup analyses demonstrated that RAD/BSA had the strongest correlation in HF with reduced ejection fraction (rs = 0.602, P < 0.001) and HF with preserved ejection fraction (rs = 0.496, P < 0.001), while LAD/BSA was most strongly correlated in HF with mildly reduced ejection fraction (rs = 0.586, P < 0.001), all remaining significant after adjustment. CONCLUSIONS: Echocardiographic parameters of the right heart volume overload were associated with TTPr, suggesting a connection between right heart overload and renal perfusion in cardiorenal syndrome. This points to potential therapeutic targets to improve renal perfusion and outcomes in CHF patients.