Renal arterial and venous doppler phenotypes in acute heart failure: insight into diastolic renal perfusion

Background

Renal dysfunction is a key determinant of outcomes in acute heart failure (AHF). While venous congestion has been increasingly recognized as a contributor to cardiorenal interactions, the role of renal arterial perfusion—particularly its diastolic component—remains incompletely characterized in the acute setting.

Methods

Patients admitted for AHF with a BNP value exceeding 200 ng/ml and who received a minimum of 40 mg of intravenous furosemide in the first 24 hours, underwent comprehensive cardiac (EF-LVOT VTI) and renal vessel ultrasound upon admission (T0) and on day 5 (T5). Renal arterial assessment included total renal VTI and diastolic renal VTI normalized for heart rate (VTIdiast/HR), while renal venous congestion was evaluated according to Venous Doppler Profile (VDP) and classified as normal, pulsatile, biphasic, monophasic. Clinical and laboratoristic variables were recorded. Associations and temporal changes were assessed using nonparametric analyses.

Results

Twenty-eight patients had paired renal Doppler measurements. Mean age was 79.9 ± 6.5

years, 39% of patients were male, median left ventricular EF at admission was 38.5%, and median LVOT VTI at T0 was 19.6 cm. No association was found between LVOT VTI or EF and Renal VTI. At admission, both renal arterial VTI and VTIdiast/HR were positively associated with eGFR (ρ=0.42, p=0.028 and ρ=0.38, p=0.049, respectively), whereas no significant association was observed between eGFR and the systolic component of renal flow, defined as the difference between total and diastolic VTI. Across worsening renal venous flow patterns, VTIdiast/HR showed a stepwise reduction at T0. From T0 to T5, no significant population-level change in diastolic perfusion indices was observed; however, patients without improvement in renal venous flow exhibited a consistent trend toward increased diastolic perfusion over time. At T5, renal Doppler indices were no longer significantly associated with eGFR.

Conclusions

In AHF, renal function at admission is more closely related to diastolic renal arterial perfusion than to systolic flow or venous congestion alone. These findings highlight the complexity of renal hemodynamics and merit further investigation to better elucidate the underlying pathophysiology and the specific role of diastolic flow in cardiorenal interactions.For image description, please refer to the figure legend and surrounding text.For image description, please refer to the figure legend and surrounding text.