Cerebrovascular responses to muscle metaboreflex activation in patients living with heart failure with reduced ejection fraction

• DOI: 10.1152/japplphysiol.00834.2024
• Publication Date: 2025-03-04T08:30:47Z
• Authors: Thomas J. Jurrissen; Adam M. S. Luchka...; Natasha G. Boyes; Rory A. Marshall; M. Rafique Khan; Alexander Zhai; Haissam Haddad; Darcy D. Marciniuk; Corey R. Tomczak; T. Dylan Olver

Impaired cerebrovascular control in patients with heart failure reduced ejection fraction (HFrEF) has been attributed to cardiac impairment and exaggerated sympathetic-mediated cerebral vasoconstriction. The goal of this study was examine the effect muscle metaboreflex activation (MMA) on hemodynamics HFrEF under conditions preserved output. It hypothesized that reductions index blood flow conductance (CVCi) during MMA would be independent Middle velocity (MCAVmean; transcranial Doppler), pressure, output (Finometer) end-tidal CO2 were examined at rest, isomteric handgrip, (post-exercise circulatory occlusion) 18 21 healthy, sex- age-matched controls. To minimize differences β-adrenergic control, withdrew from β-blockade medications prior study. Cardiac pressure not significantly different between groups any condition. MCAVmean lower rest exercise HFrEF. CVCi (MCAVmean/mean arterial pressure) decreased group. In contrast, remained unchanged increased Despite similar systemic hemodynamics, display an increase MMA. These novel findings implicate aspects other than or sympathetic constriction as underlying causes altered regulation