No abstract

Although limited by the small sample and lack of long-term observations, the study shows that oral sildenafil is a potent pulmonary vasodilator that acts synergistically with inhaled iloprost to cause strong pulmonary vasodilatation in both severe pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension.

Before iloprost therapy, the baseline 6-min walking distance was 217 +/- 31 m (mean +/- SEM), with an improvement to 305 +/- 28 m within the first three months of iloprost treatment and a subsequent decline to 256 +/- 30 m after 18 +/- 4 months. Adjunct therapy with sildenafil reversed the deterioration and increased the 6-min walk distance to 346 +/- 26 m (p = 0.002, Wilcoxon test) at three months of combined therapy, with a sustained efficacy up to 12 months (349 +/- 32 m, p = 0.002). The distribution of New York Heart Association functional classes (IV/III/II) improved from September 9, 2000, before sildenafil, to January 8, 2003, after nine to 12 months with sildenafil. All hemodynamic variables changed favorably: pulmonary vascular resistance decreased from 2,494 +/- 256 before sildenafil to 1,950 +/- 128 dynes.s.cm(-5).m(2) after three months of adjunct sildenafil (p = 0.036). Two patients died of severe pneumonia during the period of combined therapy. No further serious adverse events occurred. CONCLUSIONS; In patients with severe PAH deteriorating despite ongoing prostanoid treatment, long-term adjunct oral sildenafil improves exercise capacity and pulmonary hemodynamics. A combination of prostanoids and sildenafil is an appealing concept for future treatment of pulmonary hypertension.

No abstract

Only a small percentage of patients with chronic thromboembolic pulmonary hypertension are eligible for pulmonary thrombendarterectomy. We investigated the effects of oral sildenafil on hemodynamics and exercise capacity in 12 nonoperable chronic thromboembolic pulmonary hypertension patients. All patients were in disease progression despite sufficient long-term anticoagulation and the best supportive care and suffered from severe pulmonary hypertension (pulmonary vascular resistance index 1,935 +/- 228 dyn. s. cm-5. m2, cardiac index 2.0 l. min-1. m-2, 6-minute walking distance 312 +/- 30 m). After approximately 6 months of sildenafil treatment, pulmonary hemodynamics and exercise capacity improved significantly (pulmonary vascular resistance index 1,361 +/- 177 L. min-1. m2, p = 0.004, cardiac index 2.4 +/- 0.2 L. min-1. m-2, p = 0.009, 6-minute walking distance 366 +/- 28 m, p = 0.02). Therefore, oral sildenafil may offer a new option for medical treatment of this devastating disease.