Echoes of the heart and kidneys: exploring intrarenal hemodynamics in heart failure with preserved ejection fraction

Abstract Introduction Renal impairment is a prevalent condition associated with poor prognosis across all phenotypes of heart failure (HF). The renal arterial resistance index (RRI) has shown potential in assessing renal function and predicting outcomes in patients with heart failure with preserved ejection fraction (HFpEF) [1]. Purpose This study aimed to explore intrarenal hemodynamics and left ventricular filling pressure in patients with heart failure with preserved ejection fraction (HFpEF). Methods The study involved 200 patients who underwent transthoracic echocardiography with color and pulsed Doppler imaging. Doppler ultrasound of the renal vessels was also performed, during which the following parameters were assessed: renal resistance index (RRI), renal pulsatility index (RPI), acceleration time (AT), renal volume (RV), and the RV/RRI ratio. Results Analysis of the relationship between left ventricular diastolic function parameters and the arterial stiffness index revealed a statistically significant negative correlation between RRI and the E/A ratio (r = -0.280, p < 0.01) and a statistically significant positive correlation between RRI and the E/E′ ratio (r = 0.372, p < 0.01), indexed left atrial volume (r = 0.410, p < 0.01), and peak velocity of tricuspid regurgitation (r = 0.354, p < 0.01). These findings indicate that intrarenal hemodynamics (IRH) parameters are strongly associated with the presence of diastolic dysfunction. Conclusions In our study, patients with higher IRR and IPR values exhibited elevated E/e′ ratio values. The E/e′ ratio is widely recognized as an index reflecting increased left ventricular filling pressures due to diastolic dysfunction. RRI could serve as a predictor of prognosis in patients with heart failure with preserved ejection fraction.