Modulation of Pulsatile Left Ventricular Afterload by Renal Denervation in Heart Failure With Preserved Ejection Fraction

Abstract

Background: Arterial stiffening contributes to hemodynamic derangements in heart failure with preserved ejection fraction (HFpEF). We sought to investigate the impact of renal denervation on pulsatile left ventricular loading in patients with HFpEF and hypertensive patients without heart failure (control). Methods: Patients underwent renal denervation for treatment of hypertension and were followed up at 3 months at a single center. A validated computer model of the arterial tree, noninvasive aortic flow curves, left ventricular volumes, and E/e′ as inputs were used to determine key parameters of left ventricular vascular load. Results: In comparison to controls (n=30), patients with HFpEF (n=30) demonstrated lower total arterial compliance (mean difference, −0.41 [95% CI, −0.72 to −0.10] mL/mm Hg), higher impedance of the proximal aorta (Zc: 0.02; 0.01 to 0.04 mHg·s/mL), premature wave reflections (shorter backward wave transit time normalized to ejection time: −3.5; −6.5% to −0.5%), and higher wave reflection magnitude (reflection coefficient: 7.3; 2.8% to 11.9%). Overall, daytime systolic (−9.2; −12.2 to −6.2 mm Hg) and diastolic blood pressures (−5.9; −7.6 to −4.1 mm Hg) as well as blood pressure variability (−2.0; −3.0 to −0.9 mm Hg) decreased after renal denervation. In patients with HFpEF, total arterial compliance (0.42; 0.17 to 0.67 mL/mm Hg) and backward transit time normalized to ejection time (1.7; 0.4% to 3.0%) increased; Zc (−0.01; −0.02 to −0.01 mm Hg·s/mL) and reflection coefficient (−2.6; −5.0% to −0.3%) decreased after renal denervation. This was accompanied by a symptomatic improvement in patients with HFpEF. Conclusion: HFpEF is characterized by heightened aortic stiffness and unfavorable pulsatile left ventricular load. These abnormalities are partly normalized after renal denervation.