We tested the hypothesis that a single oral dose of sildenafil (50 mg) would improe exercise capacity and exercise hemodynamics in patients with chronic systolic HF through pulmonary asodilation.

• 本研究中，我们考查了慢性收缩性心衰患者单剂昔多芬（50mg）能否通过扩张肺血管来改善患者的运动量以及运动血流动力学。