Study of Sildenafil Effects in Combination With Rehabilitation in Patients With Chronic Obstructive Pulmonary Disease (COPD) and Associated Pulmonary Hypertension
Study of Sildenafil Effects in Combination With Rehabilitation in Patients With Chronic Obstructive Pulmonary Disease (COPD) and Associated Pulmonary Hypertension
Sildenafil is a phosphodiesterase-5 inhibitor that has been approved for the treatment of
 pulmonary arterial hypertension with orphan drug designation. Sildenafil modulates the nitric
 oxide (NO) pathway in the vessel wall. Since this pathway is impaired in pulmonary arteries
 of patients with pulmonary hypertension (PH) associated with chronic obstructive pulmonary
 disease (COPD), the investigators hypothesized that sildenafil might improve pulmonary
 hemodynamics and increase exercise tolerance in this condition.
It is a prospective, randomized, double-blind, placebo controlled trial to assess the effect
 of 3 months treatment with sildenafil (20 mg/8 h), added to a pulmonary rehabilitation
 program, on exercise tolerance. Subjects: 60 patients (30 by treatment group). Main end-point
 variable: endurance time in constant work exercise test (CWET). Other measurements: 6 min
 walk distance, performance in incremental exercise test, physiological and metabolic response
 at iso-time and iso-load in CWET, dyspnea, and health-related quality of life.
Inclusion Criteria:

 -  COPD, FEV1 < 80% ref. and FEV1/FVC < 0.7 post bronchodilator

 -  Age 40-80 years

 -  Pulmonary hypertension

 -  Consent to participate in the study

 Exclusion Criteria:

 -  Pulmonary or extrapulmonary disease that modifies gas exchange or pulmonary
 hemodynamics

 -  Recent exacerbation (<4 weeks) (temporally)

 -  Patients treated with nitrates or CYP3A4 inhibitors (ketoconazole, itraconazole,
 ritonavir)

 -  Ischemic optic neuropathy

 -  Patients treated with phosphodiesterase-5 inhibitors

 -  Patients with ischemic cardiopathy

 -  Systemic disease that could modified the results

 -  Patients unable to practise exercise