Affiliation:
1. From Abteilung Kardiologie, Medizinische Hochschule Hannover, Hannover, Germany.
Abstract
Background
—Chronic heart failure (CHF) is associated with endothelial dysfunction including impaired endothelium-mediated, flow-dependent dilation (FDD). There is evidence for increased radical formation in CHF, raising the possibility that nitric oxide is inactivated by radicals, thereby impairing endothelial function. To test this hypothesis, we determined the effect of the antioxidant vitamin C on FDD in patients with CHF.
Methods and Results
—High-resolution ultrasound and Doppler was used to measure radial artery diameter and blood flow in 15 patients with CHF and 8 healthy volunteers. Vascular effects of vitamin C (25 mg/min IA) and placebo were determined at rest and during reactive hyperemia (causing endothelium-mediated dilation) before and after intra-arterial infusion of
N
-monomethyl-
l
-arginine (L-NMMA) to inhibit endothelial synthesis of nitric oxide. Vitamin C restored FDD in patients with heart failure after acute intra-arterial administration (13.2±1.7% versus 8.2±1.0%;
P
<.01) and after 4 weeks of oral therapy (11.9±0.9% versus 8.2±1.0%;
P
<.05). In particular, the portion of FDD mediated by nitric oxide (ie, inhibited by L-NMMA) was increased after acute as well as after chronic treatment (CHF baseline: 4.2±0.7%; acute: 9.1±1.3%; chronic: 7.3±1.2%; normal subjects: 8.9±0.8%;
P
<.01).
Conclusions
—Vitamin C improves FDD in patients with CHF as the result of increased availability of nitric oxide. This observation supports the concept that endothelial dysfunction in patients with CHF is, at least in part, due to accelerated degradation of nitric oxide by radicals.
Publisher
Ovid Technologies (Wolters Kluwer Health)
Subject
Physiology (medical),Cardiology and Cardiovascular Medicine
Reference25 articles.
1. Alterations in vasomotor tone in congestive heart failure
2. St Cyres lecture. Endothelium in control.
3. Endothelial function in chronic congestive heart failure
4. Hayoz D Drexler H Münzel T Hornig B Zeiher A Just H Brunner HR Zelis R. Flow-mediated arteriolar dilation is abnormal in congestive heart failure. Circulation . 1993;87(suppl VII):VII-92-VII-96.
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