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Updated: Jun 27, 2026

Increasing Pulmonary Artery Pulsatile Flow Improves Hypoxic Pulmonary Hypertension in Piglets
Published on: May 11, 2015
[Phosphodiesterase type 5 inhibitors for pulmonary arterial hypertension]
Masahito Sakuma1, Kunio Shirato
1Division of Internal Medicine, Onagawa Municipal Hospital.
Abstract:
The therapeutic effects of phosphodiesterase type 5 inhibitors in patients with pulmonary arterial hypertension (PAH) were reviewed. A double-blind, placebo-controlled study named SUPER-1 showed that sildenafil improved exercise capacity, WHO functional class, hemodynamics, and quality of life. Two randomized, double-blind, crossover studies, showed that sildenafil improved exercise tolerance and quality of life, and reduced estimated pulmonary artery systolic pressure. The dose independent effects of sildenafil on PAH are controversial. There are few case-reports that show vardenafil and tadalafil have benefits in PAH patients. A double-blind study of tadalafil in PAH patients is ongoing.
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