Abnormal vascular responses in human chronic cardiac failure are both endothelium dependent and endothelium independent

• Published in: Heart (British Cardiac Society) Vol. 80; no. 2; pp. 141 - 145
• Main Authors: Maguire, S M, Nugent, A G, McGurk, C, Johnston, G D, Nicholls, D P
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd and British Cardiovascular Society 01-08-1998; BMJ; BMJ Publishing Group LTD
• Subjects: Aged; Aged, 80 and over; Beta blockers; Biological and medical sciences; Blood pressure; Cardiology. Vascular system; Cardiovascular disease; Drug dosages; Endothelium; Endothelium, Vascular - drug effects; Endothelium, Vascular - physiopathology; Female; Forearm - blood supply; Heart; Heart failure; Heart Failure - physiopathology; Heart failure, cardiogenic pulmonary edema, cardiac enlargement; Humans; Hypertension; Laboratories; Male; Medical sciences; Muscle, Smooth, Vascular - drug effects; Muscle, Smooth, Vascular - physiopathology; Nitrates; Nitric Oxide Synthase - antagonists & inhibitors; Nitroglycerin - pharmacology; omega-N-Methylarginine - pharmacology; Plethysmography; Quality of life; Regional Blood Flow - drug effects; Serotonin; Serotonin - pharmacology; Smooth muscle; Studies; Vasodilator Agents - pharmacology; Human; Heart failure; Regional blood flow; Pharmacologic test; Pathophysiology; Serotonin; Cardiovascular disease; Exploration; Biosynthesis; Peripheral hemodynamics; Endothelium; Vasomotricity; Forearm; Heart disease; Nitric oxide; Nitroglycerin; Inhibition
• ISSN: 1355-6037; 1468-201X
• DOI: 10.1136/hrt.80.2.141

Objective To study underlying vascular responses in chronic heart failure in patients without ACE inhibitor treatment, and to compare them with age matched controls. Design Forearm blood flow was studied using venous occlusion plethysmography in patients with chronic heart failure (n = 12) and matched controls (n = 13), after infusion of L-NMMA (a nitric oxide synthase inhibitor), glyceryl trinitrate (an endothelium independent vasodilator), and serotonin (an endothelium dependent vasodilator). Results L-NMMA produced significant vasoconstriction in normal subjects (forearm blood flow reduced by 24%), but not in patients (6%; difference between groups p < 0.03). The vasodilator responses to glyceryl trinitrate were impaired in patients (p < 0.02). In normal controls, serotonin produced initial dilatation, followed by vasoconstriction at high doses. In patients, no vasodilator responses were observed, only late vasoconstriction (p < 0.03). Conclusions The vascular responses of patients are confirmed as being abnormal. The lack of response to L-NMMA suggests that nitric oxide does not contribute to basal vascular tone in patients with chronic heart failure. The responses to glyceryl trinitrate and to serotonin suggest that there is both smooth muscle and endothelial dysfunction in patients with chronic heart failure.