Disturbed Blood Flow Acutely Increases Endothelial Microparticles and Decreases Flow Mediated Dilation in Patients With Heart Failure With Reduced Ejection Fraction

Abstract

IntroductionDisturbed blood flow, characterized by high retrograde and oscillatory shear rate (SR), is associated with a proatherogenic phenotype. The impact of disturbed blood flow in patients with heart failure with reduced ejection fraction (HFrEF) remains unknown. We tested the hypothesis that acute elevation to retrograde and oscillatory SR provoked by local circulatory occlusion would increase endothelial microparticles (EMPs) and decrease brachial artery flow-mediated dilation (FMD) in patients with HFrEF.MethodsEighteen patients with HFrEF aged 55 ± 2 years, with left ventricular ejection fraction (LVEF) 26 ± 1%, and 14 control subjects aged 49 ± 2 years with LVEF 65 ± 1 randomly underwent experimental and control sessions. Brachial artery FMD (Doppler) was evaluated before and after 30 min of disturbed forearm blood flow provoked by pneumatic cuff (Hokanson) inflation to 75 mm Hg. Venous blood samples were collected at rest, after 15 and 30 min of disturbed blood flow to assess circulating EMP levels (CD42b−/CD31+; flow cytometry).ResultsAt rest, FMD was lower in patients with HFrEF compared with control subjects (P < 0.001), but blood flow patterns and EMPs had no differences (P > 0.05). The cuff inflation provoked a greater retrograde SR both groups (P < 0.0001). EMPs responses to disturbed blood flow significantly increased in patients with HFrEF (P = 0.03). No changes in EMPs were found in control subjects (P > 0.05). Disturbed blood flow decreased FMD both groups. No changes occurred in control condition.ConclusionCollectively, our findings suggest that disturbed blood flow acutely decreases FMD and increases EMP levels in patients with HFrEF, which may indicate that this set of patients are vulnerable to blood flow disturbances.

Effects of Postprandial Lipemia Combined With Disturbed Blood Flow on the Flow-Mediated Dilation, Oxidative Stress, and Endothelial Microvesicles in Healthy Subjects

“…Low shear rate (SR) reduces NO bioavailability by decreasing eNOS expression, thereby exposing the endothelium to the atherogenic effect of risk factors. In humans, it has been consistently shown that acute elevations to retrograde and oscillatory SR decrease the FMD of atherosclerosis-prone and resistant conduct arteries ( Thijssen et al, 2009 ; Schreuder et al, 2014 ; Silva et al, 2021 ). However, the interactive effect of blood flow disturbances and PPL on endothelial function is currently unknown.…”

“…Previous evidence showed that a single high-fat meal produced a significant increase of EMV plasma levels in healthy normolipidemic individuals ( Ferreira et al, 2004 ; Tushuizen et al, 2006 ). Also, acute elevations in retrograde and oscillatory SR on the brachial artery increases EMV levels in the circulation of healthy subjects ( Whittaker and Przyklenk, n.d. ; Jenkins et al, 2013 ) and patients with risk factors ( Rocha et al, 2018 ) and cardiovascular disease ( Silva et al, 2021 ). However, whether the combination of PPL and DBF exacerbate the increase in EMV levels is also unknown.…”