View clinical trials related to Constriction, Pathologic.
Filter by:Narrowing of coronary arteries interferes with blood flow and can cause chest pain. Cardiologists sometimes quantify the extent of the narrowing by measuring the fractional flow reserve (the ratio of the pressure in the aorta to the pressure downstream of the narrowing under conditions of maximal flow). We propose a new technique based on principles of wave intensity analysis (WIA) to better assess coronary stenosis and the significance of the narrowing without the need for administration of vasodilator agents such as adenosine. This would simplify assessment and improve our ability to advise patients whether stent treatment will help their symptoms.
Narrowing of the main valve which controls blood leaving the heart leads to a marked increase in death. To overcome this narrowing the heart muscle thickens abnormally and contracts more vigorously. However, in doing so, blood flow patterns to the heart muscle change through mechanisms which are incompletely understood. New technology allows such heart valve blockages to be fixed using balloons and metal stents inserted through tubes placed in arteries in the leg. Using sensors placed in these tubes it is possible to make detailed measurements of coronary flow and pressure, and apply new mathematical techniques to allow a better understanding of the detrimental effects that aortic stenosis has on coronary flow, before and after valve surgery.
A single arm, prospective multicenter non-randomized pivotal clinical trial evaluating the Edwards SAPIEN XT™ transcatheter heart valve (model 9300TFX), NovaFlex™ transfemoral delivery system, Ascendra2™ transapical delivery system and crimper accessories. The trial includes a premarket pivotal cohort to evaluate the system performance as well as a post market clinical follow-up phase involving long term follow-up of all patients to evaluate the safety of investigational devices up to 5 years.
The purpose of this study is to collect long-term follow-up data of the CryoValve SG Pulmonary Human Heart Valve.
Benign biliary strictures can be endoscopically treated with plastic or self-expandable metal stents (SEMS). The purpose of the prospective randomized study is to compare the safety and feasibility of covered SEMS with multiple plastic stents in the treatment of benign biliary stricture caused by chronic pancreatitis.
The aim of the trial is to assess the efficacy of the Paclitaxel-coated SeQuent®Please angioplasty balloon in the treatment of stenoses in native coronary arteries compared to a drug eluting stent.
Pulmonary hypertension is common in patients with aortic stenosis and is associated with worse operative and long-term outcomes. Sildenafil has been shown to reduce pulmonary artery pressure and improve exercise performance in patients with left-sided heart failure, but this has not been tested in patients with aortic stenosis. We hypothesize that Sildenafil will produce a clinically significant decrease in pulmonary artery pressure in patients with severe aortic stenosis. The dose of Sildenafil that produces a significant decrease in pulmonary artery pressure will be safe and well tolerated in patients with and without a depressed ejection fraction.
Neurogenic intermittent claudication is a specific symptom complex occurring in patients with lumbar spinal stenosis. Characteristic of this disease is the occurrence of increasing leg, buttock or groin pain with or without lower back pain when walking a certain distance or reclining. Bending forward or sitting leads to a rapid pain relief. Lumbar spinal stenosis is defined as a reduction of the diameter of the spinal canal. The mechanism leading to stenosis is a remodeling and overgrowth of the spinal canal with osteophyte formation. Any loss of tissue or decrease of the disc height results in a relative laxity of the ligament structures and accelerates the degeneration of the spinal joints. As a therapy option, conservative therapy with oral analgesics and physical therapy is considered. This treatment can be intensified by adding epidural pain treatment. Is the conservative treatment not successful surgical intervention is necessary. In patients over 65 years of age operative decompression of the lumbar spinal stenosis constitutes the most common surgical operation of the spine. A relatively new therapy alternative is the interspinous process decompression (IPD). Studies have shown that the IPDs prevent narrowing of the spinal canal and neural foramens. The study is intended as a randomised, monocentre study to investigate the safety and the benefit of a minimally invasive percutaneous IPD-device in comparison with the best non-surgical operative treatment of lumbar spinal stenosis.
The purpose of the study is to evaluate the safety and effectiveness of the PTX-coating on the Formula PTX Balloon-Expandable Stent in treatment of renal artery stenosis.
A randomized clinical trial of transcatheter aortic valve implantation (TAVI) versus conventional surgical aortic valve replacement (SAVR) in patients older than 70 years of age suffering from severe aortic valve stenosis. Study hypothesis: TAVI will reduce post-interventional morbidity and mortality compared to SAVR.