Background: Vasoactive intestinal peptide (VIP) is a peptidergic neurotransmitter and a vasodilator with positive inotropic and chronotropic properties. Whether and how VIP contributes to the neuroendocrine response in heart failure (HF) is disputed, and there are no data on VIP in pressure overload-induced HF.
Methods: We studied 129 adults with isolated aortic valve stenosis (AS). Blood was sampled from the aortic root and, in a subset of 48 patients, also from the coronary sinus for determination of VIP by radioimmunoassay. HF was diagnosed according to the European Society of Cardiology criteria.
Results: Plasma VIP (mean+/-S.E.M.) was slightly higher in patients with HF (22.6+/-0.9 pmol/l, n=41) than in patients free of HF (21.1+/-0.5 pmol/l, n=88) or in 11 control patients without structural heart disease (20.0+/-1.3 pmol/l, n=11) (p=0.030 across the groups). VIP did not correlate with any measurement of cardiac structure or function in AS. The change in plasma VIP from aortic root to coronary sinus averaged +1.2+/-0.4 pmol/l in the 11 control patients (p=0.021), +1.2+/-0.2 pmol/l in 33 AS patients free of HF (p<0.001) and +0.8+/-0.3 pmol/l in 15 AS patients with HF (p=0.037).
Conclusions: Both structurally normal and diseased hearts release VIP into the coronary sinus. Although marginally elevated in the systemic circulation, VIP is unlikely to contribute significantly to the neuroendocrine activation in HF due to pressure overload.