title: Preserved flow-mediated dilation in adults with cyanotic congenital heart disease.
abstract: Adults with cyanotic congenital heart disease (CCHD) have been shown to have endothelial dysfunction in the forearm resistance vessels as assessed with venous occlusion plethysmography. Whether these abnormalities are confined to the microvasculature or reflect generalized endothelial dysfunction remain unknown. We used high-resolution ultrasound to compare flow responses and endothelial-dependent flow-mediated dilation (FMD) in the brachial artery of 13 adult patients with CCHD and 14 healthy controls. High-dose vitamin C was infused to evaluate the possible role of reactive oxygen species on endothelial vasomotor function. FMD was measured both prior to and after vitamin C infusion. Sublingual glyceryl nitrate was given to assess endothelium-independent responses. FMD did not differ among patients with CCHD and controls either before (6.2 +/- 4.1, 5.1 +/- 2.6%, p = 0.44) or after (5.1 +/- 2.8, 5.2 +/- 3.1%, p = 0.90) vitamin C infusion. Endothelium-independent vasodilatation was similar in both groups (14.3 +/- 3.7, 13.2 +/- 4.4%). There were no differences in baseline flow or in measures of reactive hyperemia. Adults with CCHD appear to have preserved endothelial function in their conduit arteries. This suggests that these patients are not at an increased risk of premature atherosclerotic cardiovascular events.
authors.affiliation: Department of Cardiology, Aarhus University Hospital Skejby, Brendstrupgaardsvej 100, 8200 Aarhus N, Denmark. Christian.M.Pedersen@ki.au.dk
authors.forename: Christian M
authors.initials: CM
authors.lastname: Pedersen
authors.forename: Michael R
authors.initials: MR
authors.lastname: Schmidt
authors.forename: Bente
authors.initials: B
authors.lastname: Mortensen
authors.forename: Hussain
authors.initials: H
authors.lastname: Contractor
authors.forename: Hans Erik
authors.initials: HE
authors.lastname: Bøtker
authors.forename: Rajesh K
authors.initials: RK
authors.lastname: Kharbanda
authors.forename: Keld E
authors.initials: KE
authors.lastname: Sørensen
mesh_terms: D000328:Adult; D001205:Ascorbic Acid / Q000008:administration & dosage; D001783:Blood Flow Velocity; D001916:Brachial Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D016022:Case-Control Studies; D003490:Cyanosis / Q000503:physiopathology*; D004541:Eisenmenger Complex / Q000503:physiopathology*; D004730:Endothelium, Vascular / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D005260:Female; D006330:Heart Defects, Congenital / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D005996:Nitroglycerin / Q000008:administration & dosage; D018384:Oxidative Stress; D018709:Statistics, Nonparametric; D014463:Ultrasonography
chemical_list: D005996:Nitroglycerin; D001205:Ascorbic Acid