Exercise Oscillatory Breathing and Sildenafil in Heart Failure
Status:
Completed
Trial end date:
2010-06-01
Target enrollment:
Participant gender:
Summary
Exercise oscillatory breathing (EOB) is a ventilatory abnormality that occurs in
approximately 20% of heart failure (HF) patients and carries a very unfavourable prognosis.
Pathophysiology seems quite complex and putative mechanisms include increased pulmonary
capillary pressure and pulmonary vasoconstriction, circulatory blood-flow fluctuations in the
pulmonary arterial system and instability of ventilatory control.
Inhibition of the phosphodiesterase 5 (PDE5) isoenzyme favourably regulates pulmonary
vascular tone and permeability through over signaling of the endothelial nitric oxide
pathway. The investigators tested the hypothesis that sildenafil would reverse the EOB
pattern in patients with HF and pulmonary hypertension.