RESUMO
OBJECTIVE: Vasoactive intestinal peptide (VIP) is a powerful vasodilatory neuropeptide with positive inotropic and chronotropic properties. The aim of the study was to investigate the pathophysiological role of VIP in heart failure. DESIGN AND RESULTS: VIP was assayed in plasma within the first in-hospital day in 52 patients with heart failure due to dilated cardiomyopathy. The concentration of VIP was: (i) higher in patients than in healthy subjects; (ii) higher in elderly but not in younger patients compared with healthy controls; (iii) inversely related to NYHA class: higher in NYHA 2 than in NYHA > 2 patients and in normal subjects, in both young and elderly groups; (iv) not correlated with echocardiographic parameters and (v) not influenced by the aetiology of dilated cardiomyopathy. CONCLUSIONS: The physiological properties of VIP suggest that the increased plasma concentrations in patients with heart failure contribute to restore the compromised haemodynamic balance either by improving myocardial performance or by counteracting the harmful effects related to simultaneous activation of other neuroendocrine systems, i.e. the sympathetic and renin-angiotensin systems. Decreased VIP concentrations are related to progressive worsening of heart failure. The higher VIP concentrations in elderly patients compared with healthy controls suggest that the capacity to increase VIP production is preserved in older people.
