Essential hypertension was associated with markedly impaired flow-mediated dilatation (3.6% vs 10.2% in normotensive controls), which was strongly determined by reduced peripheral flow reserve.
Observational (n=81)
Does reduced peripheral flow reserve impair endothelial function in conduit arteries of patients with essential hypertension?
Reduced peripheral flow reserve contributes to endothelial dysfunction in upstream conduit arteries in patients with essential hypertension.
Absolute Event Rate: 3.6% vs 10.2%
BACKGROUND: A diminished flow reserve in resistance vessels is a hallmark of hypertensive microvascular disease. Hypertension is associated with structural alterations in the microcirculation and a reduced endothelium-dependent dilation in conduit arteries. Both have been demonstrated to predict future cardiovascular events. OBJECTIVE: We hypothesized that a reduced peripheral flow reserve impairs endothelial function in upstream conduit arteries in patients with arterial hypertension. DESIGN: In 43 hypertensive patients (HT) and 38 normotensive controls (NT) endothelial function of the brachial artery was assessed by measurement of flow-mediated dilatation (FMD), using high-resolution ultrasound. Peripheral flow reserve (FR) was determined via measurements of forearm blood flow at rest and during increments of reactive hyperaemia, using venous occlusion plethysmography. RESULTS: FMD was markedly impaired in HT (3.6 +/- 0.3%) as compared with NT (10.2 +/- 0.3%), whereas maximum brachial artery diameter following endothelium-independent dilatation was similar in both groups. In hypertensive patients FR was significantly reduced (HT, 3.2 versus NT, 6.0) during reactive hyperaemia after 5 min of ischaemia. FR was associated with FMD (r = 0.68, P < 0.01). Multiple stepwise regression analysis identified FR as a strong independent variable determining the extent of FMD (r2 = 0.46, P < 0.01). In HT the dose-response curve of FMD upon stepwise increases of FR was shifted significantly to the right. Normalization of FR improved FMD in HT by more than 60%. CONCLUSIONS: In essential hypertension a reduced FR contributes to the endothelial dysfunction of upstream conduit arteries. These findings may have therapeutic and prognostic implications in patients with arterial hypertension.
Lauer et al. (Tue,) conducted a observational in Essential hypertension (n=81). Essential hypertension vs. Normotensive controls was evaluated on Flow-mediated dilatation (FMD). Essential hypertension was associated with markedly impaired flow-mediated dilatation (3.6% vs 10.2% in normotensive controls), which was strongly determined by reduced peripheral flow reserve.