29 September 2006
Background: Prostanoids are a well-established therapy for pulmonary arterial hypertension (PAH), and observational studies suggest their efficacy even in chronic thromboembolic pulmonary hypertension (CTEPH) patients. Objective: To compare the effects of 6 months of treatment with beraprost, an orally-active prostacyclin analog, in patients with distal CTEPH and PAH. Design: Case-control study. Population: Sixteen patients with severe pulmonary hypertension (NYHA II–IV), eight with distal CTEPH matched with eight patients with idiopathic PAH for similar effort tolerance. Methods: All patients were in stable clinical and hemodynamic condition for 3 months with maximal standard therapy. During the titration phase (4 weeks) beraprost was increased to maximal tolerated dose (mean daily dosage: CTEPH 275 ± 47 µg, PAH 277 ± 47 µg) in adjunction of standard therapy, patients were followed-up for 6 months. Main Outcome Measures: World Heart Organization (WHO) functional class, exercise capacity measured by distance walked in 6 min, and systolic pulmonary pressure (echocardiography), were evaluated at baseline, and at 1-, 3- and 6-month interval. Results: At 6 months WHO class decreased significantly in both groups (CTEPH from 2.7 ± 0.6 to 2.0 ± 0.24, p < 0.05; PAH from 3.0 ± 0.26 to 2.1 ± 0.25, p < 0.05), similarly the 6-min walk distance increased significantly from baseline (CTEPH from 312 ± 31 to 373 ± 29 m, p < 0.003; PAH from 303 ± 31 to 347 ± 29, p < 0.0003). Systolic pulmonary artery pressure showed a trend toward lower value (CTEPH from 85 ± 7 m to 81 ± 6 mm Hg, p = NS; PAH from 89 ± 7 to 82 ± 5, p = NS). During the observation period we did not have any death. The drug was well-tolerated with minor side-effects. Conclusion: In patients with CTEPH beraprost had similar mid-term clinical and hemodynamic improvements than in patients with PAH.