原发性肺动脉高压（PPH）预后不良，一般于5年内死于进行性右心衰竭。本病尚无特效疗法。抗凝疗法能预防血栓栓塞。血管扩张疗法的目的是抑制肺动脉收缩，从而降低右室后负荷，增加右心排血量；血管扩张疗法的终点是降低肺循环血管阻力，而不引越明显的体循环低血压。已用过的 Primary pulmonary hypertension (PPH) has a poor prognosis and generally dies of progressive right heart failure within 5 years. There is no effective treatment for this disease. Anticoagulant therapy can prevent thromboembolism. The purpose of vasodilatation therapy is to suppress pulmonary artery contractions, thereby reducing the right ventricular afterload and increasing right ventricular output; the end point of vasodilatation therapy is to reduce vascular resistance in the pulmonary circulation without inducing obvious systemic hypotension. Used