View clinical trials related to Pulmonary Hypertension.
Filter by:The purpose of the study is is to determine the effect, on the lung circulation, of BQ-123, an investigational compound which is not approved by the FDA.
Pulmonary hypertension (PHT) is an elevation of pulmonary arterial pressure (PAP) that can be the result of heart, lung or systemic disease. PHT also complicates chronic hemodialysis (HD) therapy immediately after the creation of an arteriovenous (AV) access, even before starting HD therapy. It tends to regress after temporary AV access closure and after successful kidney transplantation. Affected patients have significantly higher cardiac output. This syndrome is associated with a statistically significant survival disadvantage. The laboratory hallmark of this syndrome is reduced basal and stimulatory nitric oxide (NO) levels. It appears that patients with end-stage renal disease (ESRD) acquire endothelial dysfunction that reduces the ability of their pulmonary vessels to accommodate the AV access-mediated elevated cardiac output, exacerbating the PHT. Doppler echocardiographic screening of ESRD patients scheduled for HD therapy for the occurrence of PH is indicated. Early diagnosis enables timely intervention, currently limited to changing dialysis modality such as peritoneal dialysis or referring for kidney transplantation.An echocardiographic diagnosis of pulmonary hypertension (PHT) is made when the systolic pulmonary arterial pressure (PAP) exceeds normal values (30 mmHg). In mild PHT, PAP values range up to 45 mmHg, in moderate PHT, PAP is between 45 and 65 mmHg, and in severe PHT, PAP values are greater than 65 mmHg. Systolic PAP equals cardiac output times pulmonary vascular resistance (PVR), (i.e., PAP = cardiac output × PVR). Increased cardiac output by itself does not cause PH because of the enormous capacity of the pulmonary circulation to accommodate the increase in blood flow. Therefore development of PHT requires pathologic, marked elevation of pulmonary vascular resistance. The presence of PH may reflect serious pulmonary vascular disease, which can be progressive and fatal. Consequently, an accurate diagnosis of the cause of PHT is essential in order to establish an effective treatment program. Pulmonary hypertension can occur from diverse etiologies. In 1996 we first noted unexplained PH in some long-term hemodialysis (HD) patients during an epidemiologic study of this disorder (Nakhoul F and Yigla M Rambam Medical Cemter-Haifa). It was assumed that their PHT was related to end-stage renal disease (ESRD) or to long-term HD therapy via an arteriovenous (AV) access. There are several potential explanations for the development of PHT in patients with ESRD. Hormonal and metabolic derangement associated with ESRD might lead to vasoconstriction of pulmonary vessels and increased pulmonary vascular resistance. Values of PAP may be further increased by high cardiac output resulting from the AV access itself, worsened by commonly occurring anemia and fluid overload. Despite almost five decades of HD therapy via a surgically created, often large, hemodynamically significant AV access the long-term impact of this intervention on the pulmonary circulation has received little attention. RD versus AV HD via AV access Proposed Mechanisms: 1. Elevated Parathyroid hormone 2. Metastatic Calcification due to the increase of the calcium-phosphor multiple 3. High cardiac output 4. Nitric oxide-endothelin metabolism 5. A-v Access flow These observations indicate a role for AV access-mediated elevations in cardiac output in the pathogenesis of PH. The correlation between access flow and PAP values has not yet been studied. Since patients undergoing HD therapy via AV access had PH that reversed after successful kidney transplantation and after short AV access compression, we concluded that both ESRD and AV access-mediated elevated cardiac output are required for the development PH. From a physiologic point of view, due to the enormous capacity of the pulmonary microcirculation, increased cardiac output by itself cannot cause PH. It is the inability of the pulmonary circulation of some ESRD patients to accommodate the AV access-mediated elevated cardiac output that leads to the development of PH.
Chronic obstructive pulmonary disease (COPD)can be complicated by an increased pressure in the pulmonary circulation. This worsens the prognosis, but so far it is unknown whether treatment of the increased pulmonary blood pressure betters the patients symptoms. In this study 32 patients with increased pulmonary blood pressure due to COPD will be randomized to 3 months treatment with placebo or sildenafil, which is known to lower the pulmonary blood pressure in other types of pulmonary hypertension. Our hypothesis is that treatment with sildenafil in these patients will improve the functional capacity measured by the distance walked in 6 minutes and life quality.
The purpose of this study is to evaluate the efficacy and safety of vardenafil in the treatment of pulmonary arterial hypertension.
The study is being done to investigate what happens to sildenafil in the body and how long it takes to get rid of this drug. Understanding how long the drug stays in the body and how it is changed by the body will help doctors determine the best dose. We also want to learn how well the medicine works based on the size of the dose or amount in the bloodstream.
A two-stage prospective observational cohort study in scleroderma patients to evaluate screening tests and the incidence of pulmonary arterial hypertension and pulmonary hypertension
The purpose of this study is to establish single-dose tolerability of inhaled treprostinil sodium in idiopathic pulmonary fibrosis (IPF) patients with pulmonary hypertension, and to explore the acute hemodynamic effects over a range of tolerable doses. The safety and pharmacodynamic information obtained from this study will inform the design and conduct of future studies in inhaled treprostinil sodium in this population.
Bosentan has been largely used in the treatment of pulmonary hypertension (PH). It can improve exercise capacity, lower Borg dyspnoea score nad these effects are usually associated with the concomitant improvement in cardiopulmonary haemodynamics. No physiological study has so far verified the hypothesis that Bosentan may laso have an effect on the "respiratory side" of the cadio-pulmonary system (i.e. on pulmonary mechanics and work of breathing)
This study will determine if a rehabilitation exercise program can help people with pulmonary hypertension (PH) increase their physical activity. Patients with PH have an increase in blood pressure in the pulmonary blood vessels (artery, vein or capillaries) that leads to shortness of breath, dizziness, fainting and other symptoms. Healthy volunteers and people with pulmonary hypertension between 21 and 75 years of age may be eligible for this study. All participants undergo the following tests and procedures: - Medical history and physical examination - 6-minute walk test: Subjects walk as fast as they can for 6 minutes on a walking track to determine their ability to participate in physical activity. - Questionnaires: Subjects complete nine questionnaires related to their fatigue, daily physical activity, mood, and so forth. - Maximum treadmill test: The exercise begins at an easy level and gradually increases until the subject says he or she can no longer continue or the investigator decides it is not safe to continue. Subjects are fitted with a mask, electrodes and light sensors to measure how well the heart is working and how well the muscles use oxygen. Patients with pulmonary hypertension undergo the following additional procedures: - Activity monitoring: Patients wear a monitor for 3 days that measures movement and heart rate. - Group assignment: Patients are randomly assigned to Group 1 (education plus aerobic exercise) or Group 2 (education followed by exercise). - Group 1 patients will attend classes three days a week at either Inova Fairfax Hospital Pulmonary Rehabilitation Center or The National Institutes of Health for 10 weeks. Two sessions a week will include a 1 hour education session as well as a 30-45 minute track or treadmill exercise session. The third session will only include exercise. During the education patients will learn about a healthy lifestyle with pulmonary hypertension. After the 10 weeks of education and exercise, subjects repeat the 6-minute walk test, maximum treadmill test and questionnaires. - Group 2 patients participate in 2; 1-hour educational session at either the Inova Pulmonary Rehabilitation Center or The National Institutes of Health for 10 weeks. After the classes, they repeat the 6-minute walk test, maximum treadmill test and questionnaires. The following 10 weeks will consist of 3 days a week of 30-45 minute track or treadmill walking at either Inova or NIH, after which they again repeat the questionnaires, treadmill and walk tests.
A 3-month open label study to evaluate the safety and efficacy of PRX-08066 in patients with pulmonary hypertension and COPD.