Active clinical trials for "Hypertension, Pulmonary"

The safety and efficacy at 100 mg once daily for oral dose of sitaxentan sodium were demonstrated in the STRIDE clinical trial program. Sitaxentan sodium was approved in the EU, Canada and Australia. In this study, the long-term safety and efficacy after administrations of sitaxentan sodium at a dose of 100 mg alone or in combination with another medication will be investigated in Japanese PAH patients.

Ambrisentan is an endothelin receptor antagonist used for the treatment of pulmonary hypertension (PH). Based on research suggesting a role for endothelin-1 in the pathogenesis of idiopathic pulmonary fibrosis (IPF) and the poor prognosis for patients with IPF who are also diagnosed with PH, this study was designed to evaluate the effectiveness and safety of ambrisentan in that patient population.

This protocol is for subjects with pulmonary arterial hypertension and is the first of 3 studies forming the Sitaxsentan efficacy and safety trial with Randomized Prospective Assessment of Adding Sildenafil (SR-PAAS) program.

The study will assess the effect of bosentan on pulmonary vascular resistance and exercise capacity in sickle cell disease (SCD) patients diagnosed with pulmonary arterial hypertension. It consists of 3 phases: Screening, Treatment and Follow-up. During the Screening visit, the study doctor will decide if patients meet the study requirements. All potential patients will have a diagnosis of increased pulmonary artery pressures that is shown by right heart catheterization conducted shortly prior to start of study treatment. Patients will be asked to perform exercise capacity test (walking as far as possible for 6 minutes). Following the Baseline visit, the treatment phase consists of 4 additional clinic visits during which the good and bad effects of the drug are reviewed and exercise capacity test will be repeated. Patients will be treated for 16 weeks. Blood samples will be collected every month, or more often, if needed. At the end of the study, patients will be asked to repeat the right heart catheterization and exercise capacity test. After completion of the study, patients will have the option of enrolling in a long-term follow-up study where all patients will receive active drug. Patients electing not to participate in the extension study will be followed up for safety assessments for about 28 days after the end of the study treatment.

The purpose of this multi-center international trial is to evaluate the safety and effectiveness of adding iloprost or placebo (an inactive substance that contains no active study drug) to sildenafil therapy for pulmonary arterial hypertension (PAH). The study will also examine whether patients on sildenafil can reduce the number of iloprost inhalations from the approved 6 doses per day to 4 doses per day.

This study will examine how blood pressure in the lungs is controlled in healthy people, people with HIV and people with HIV and pulmonary artery hypertension (high blood pressure in the lungs, also called PAH). PAH sometimes develops in people with HIV, but it is not known why this occurs or how best to treat it. Healthy volunteers and patients with HIV infection who are 18 years of age or older may be eligible for this study. All candidates are screened with a medical history, physical examination, electrocardiogram (EKG), chest x-ray, echocardiogram and blood tests. Participants undergo the following procedures: All participants have a right heart catheterization and forearm blood flow study. Catheterization study. A catheter (plastic tube) is placed in an arm vein and possibly in an artery in the arm. Then a large catheter is passed through a vein in the groin, neck or chest. Through this "introducer" catheter, another catheter is advanced into the right side of the heart and to the pulmonary artery. A facemask is put in place to measure the amount of nitric oxide produced by the lungs. Acetylcholine is infused through the catheter and its effects on blood pressure in the lungs and on the amount of nitric oxide exhaled is measured. After about 1 hour, the catheter and facemask are removed and a new catheter is inserted through the introducer catheter into the pulmonary artery. The subject is moved into an MRI scanner where blood flow is measured after infusion of three different medications: acetylcholine (causes blood vessels to expand and slows heart rate); sodium nitroprusside (causes blood vessels to expand and increases blood flow to the heart); and L-NMMA (decreases blood flow by blocking production of nitric oxide in cells lining the blood vessels). Blood flow study. Small tubes are inserted into the artery of the patient's forearm. These are used to infuse medicines and draw blood samples. Forearm blood flow is measured using pressure cuffs placed on the wrist and upper arm, and a strain gauge (a rubber band device) placed around the forearm. When the cuffs are inflated, blood flows into the arm, stretching the strain gauge, and the flow measurement is recorded. A small lamp is positioned over the hand to measure the light reflected from the hand and blood flow in the forearm. Blood samples are then drawn to measure blood counts and proteins and other natural body chemicals. Then, forearm blood flow is measured after administration of small doses of sodium nitroprusside, acetylcholine and L-NMMA. There is a 20- to 30-minute rest period between injections of the different drugs. In addition, HIV-infected patients with PAH undergo the following tests to determine the cause of their PAH: CT scan of the lungs, pulmonary function tests, 6-minute walk test, quality-of-life assessment, assessment of difficulty in breathing, exercise testing while measuring oxygen breathed in and carbon dioxide breathed out, blood tests, monitoring of oxygen saturation during sleep for 1 night and ventilation/perfusion scan. For the ventilation/perfusion scan, the subject breathes in a small amount of radioactive aerosol while images are obtained of the radioactivity as it enters the lungs, and then pictures of the lungs are taken from multiple angles. Next, the patient receives an injection of tiny particles of albumin (a protein) containing a small amount of radioactivity and pictures of the lungs are taken that show the pattern of blood flow to the lungs. Patients with HIV and PAH who may benefit from the investigational drug, sildenafil (commonly known as Viagra), may continue to participate in the next stage of the study. They receive the first dose of sildenafil after completing the forearm blood flow study. They continue the drug for 16 weeks, returning to the clinic 1 week after the first dose and then every other week to monitor the response to treatment and drug side effects. At the end of 16 weeks, patients return to the clinic for a repeat evaluation, including blood tests, 6-minute walk test, echocardiogram, right heart catheterization and forearm blood flow study. ...

Endothelin-1 is a powerful substance that may be involved in causing hemodynamic instability (problems related to unstable blood pressure) during and after open heart surgery. Tezosentan is an investigational intravenous drug that blocks the endothelin receptors. This clinical trial will assess the potential benefit of tezosentan compared with placebo in the treatment of patients undergoing open heart surgery with cardiopulmonary bypass (CPB). Treatment time is from the start of surgery up to 24 hours.

The goal of this clinical research study is to learn if the drug nesiritide (Natrecor) is effective in lowering the pressure in your lungs. The primary objective of this study is to establish that Nesiritide (Natrecor) is effective in reducing pulmonary hypertension (PHTN) acutely as measured by a 20% reduction in the mean pulmonary arterial (PA) pressure. The secondary objectives will include: improvement in pulmonary vascular resistance (PVR), patient symptoms, exercise tolerance, frequency of toxicity, and surgeon's willingness to proceed with operation.

The purpose of the study is to see if the administration of sildenafil (Viagra) in patients with portopulmonary hypertension could be a safe and effective treatment. Portopulmonary hypertension (PTPH) is a special type of pulmonary hypertension. Pulmonary hypertension is high blood pressure in the pulmonary arteries that carry unoxygenated blood from the right ventricle of the heart to the lungs. Pulmonary hypertension results from constriction, or tightening, of the blood vessels that supply blood to the lungs. Consequently, it becomes difficult for blood to pass through the lungs, making it harder for the heart to pump blood forward. This stress on the heart leads to enlargement of the heart and eventually fluid can build up in the liver and tissues, such as in the legs. Affected patients can sometimes notice increasing shortness of breath and dizziness. There is a growing body of evidence suggesting a potential therapeutic role for this sildenafil in patients with primary pulmonary hypertension. Studies are ongoing regarding this area. Our hypothesis is that chronic oral sildenafil will successfully reduce pulmonary artery pressures by at least 25% (reduction in mean pulmonary artery pressure) and could be an effective treatment for PTPH, especially in candidates for liver transplantation Primary Hypothesis To measure the effects of a single dose of sildenafil on pulmonary arterial pressure in patients with PTPH Secondary Hypothesis To measure the effects of chronic (3 month) treatment with sildenafil on pulmonary arterial pressure, safety, and tolerability in patients with PTPH

This multicenter trial tested whether inhaled nitric oxide would reduce death or the need for oxygen in preterm infants (less than 34 weeks gestational age) with severe lung disease.