View clinical trials related to Constriction, Pathologic.
Filter by:ABSORB IV is a prospective, randomized (1:1, Absorb BVS to XIENCE), single-blind, multi-center study, registering approximately 2610 subjects from approximately 140 sites in the United States and outside the United States. ABSORB IV is a continuation of ABSORB III (NCT01751906) trial which are maintained under one protocol because both trial designs are related. The data from ABSORB III and ABSORB IV will be pooled to support the ABSORB IV primary endpoint. Both the trials will evaluate the safety and effectiveness of Absorb BVS. The ABSORB IV Randomized Controlled Trial (RCT) is designed to continue to evaluate the safety and effectiveness as well as the potential short and long-term benefits of Abbott Vascular Absorb™ Bioresorbable Vascular Scaffold (BVS) System, and the Absorb GT1™ BVS System (once commercially available), as compared to the commercially approved, control stent XIENCE.
This is a prospective, single blinded, randomized study of EndoMAXX Endoluminal Valve Technology (EVT) Fully Covered Esophageal Stent with Valve for the treatment of malignant strictures of the lower esophagus. The purpose of this study is to evaluate improvement of dysphagia due to esophageal stricture with EndoMAXX Endoluminal Valve Technology (EVT) Fully Covered Esophageal Stent with Valve (investigational device) compared to the EndoMAXX Fully Covered Esophageal Stent (reference device).
The purpose of this study is to evaluate the safety and performance of the HLT System in patients with severe aortic stenosis who present at High Risk for aortic valve replacement surgery.
The purpose of the proposed research is to explore the relationship between objectively measured physical activity and surgical intervention for lumbar spinal stenosis (LSS). Our primary hypothesis is that post-surgery, LSS patients will demonstrate increased physical activity compared to their baseline assessment. A non-intervention control group will be measured at the same time intervals as the surgical group to look at test re-test reliability. In the event that our hypothesis is rejected, and surgery does not lead to a decrease in sedentary behaviour analysis of questionnaire-based sedentary behaviour measures and objective activity-based measurement can examine the relationship between self-report and actual performance-based objective measures. The primary objective of our proposal is to determine if surgical intervention leads to increased activity, and decreased sedentary behaviour. The findings of the proposed research will inform healthcare stakeholders that if surgery alone does not lead to increased activity, a more concerted research effort may need to be made for post-surgical rehabilitation, lifestyle and physical activity counselling so that post-surgical patients may make changes toward leading more active and productive lives.
Aortic stenosis is a common valvular heart disease, affecting mainly people over age 60. It is characterized by years to decades of slow progression followed by rapid clinical deterioration and a high death rate once symptoms develop. The onset of symptoms confers a poor prognosis: patients die within an average of five years after the onset of angina, three years after the onset of syncope, and two years after the onset of heart failure symptoms. The overall mortality rate is 75% at three years without surgery. Drug therapy for it remains ineffective, and aortic valve replacement is the only recommended long-term treatment.
The purpose of this study is to document the performance of a new Fully Covered Self Expanding Metal Stents (FCSEMS) for treatment of refractory pancreatic duct strictures in patients with painful chronic pancreatitis.
Aortic stenosis is a condition whereby one of the heart valves (aortic valve) becomes narrowed, due to calcium deposition, over time. This can lead to chest pain, heart failure and sudden death. It is the commonest valve disease requiring surgery in the developed world and as the population becomes increasingly older, it is predicted that the prevalence of aortic stenosis will double in the next 20 years. Currently the only treatment is replacement of the aortic valve. Whilst this is excellent treatment, not everyone is suitable for it. The primary objective of our study is to determine whether 2 drugs used in the treatment of osteoporosis (a condition of bone thinning) can halt/retard the progression of aortic stenosis. This is on the basis that studies have suggested that altered regulation of calcium metabolism may be an important mechanism perpetuating the disease. Both drugs work by reducing calcium release into the bloodstream from bones and therefore calcification of the aortic valve. 150 patients will therefore be randomly allocated to either of the trial drugs which are denosumab,the bisphosphonate (alendronic acid), or a placebo. Positron Emission Tomography (PET) scanning is a technique where biochemically active molecules are injected and are taken up at sites of ongoing calcification activity where they emit radiation and can be detected by the PET scanner. We have previously shown that this technique can demonstrate areas of newly developing calcification on an aortic valve. We therefore propose that patients receiving bisphosphonates or denosumab will have reduced evidence of active calcification and slower progression of their disease at two years as assessed by Echocardiography (ultrasound) and a change in their calcium score (quantity of calcium on the aortic valve measured using Computed Tomography [CT] ). The data from this study will then be used to design a larger trial.
Stent placement is now widely accepted to improve the results of angioplasty (an operation to widen the blood vessel) and decreasing the need for further surgery. Despite their worldwide acceptance, stent usage is still limited by renarrowing which occurs within the stent (restenosis) in some patients within the first six months. In addition there still exists a small risk of heart attacks soon after the stent is placed. The purpose of this study is to test the safety and tolerability of trying to place the stents using a different strategy of using low pressure oversized balloon inflations as opposed to the usual high pressure balloon inflations. This may reduce injury to the artery and reduce the chance of renarrowing of the stent. In order to ensure this is a safe and effective way of performing the procedure the investigators intend to use an Intravascular ultrasound (IVUS) catheter to look from inside the artery at the stents. IVUS has proven to be the best way of ensuring optimal stent placement. Primary hypothesis: Stents will be equally well expanded and apposed using a strategy of oversized stenting at normal inflation pressures ( < 10 atmospheres ) as compared to high pressure inflation (≥14 atmospheres) as guided by intravascular ultrasound imaging. Secondary Hypothesis: There will be no difference in acute clinical endpoints (death, myocardial infarction, urgent revascularisation or stent thrombosis) using a strategy of oversized stenting at normal inflation pressure as compared to high pressure inflation. Tertiary Hypothesis: If the above is shown to be true the investigators would hope to expand the study in order to reveal a decrease in stent restenosis using a strategy of lower pressure balloon inflations. The investigators will assess the deployment characteristics of drug eluting versus bare metal stents
The primary objective of this study is to determine the reasons for balloon aortic valvuloplasty (BAV) in the current clinical setting and to determine the outcomes of BAV in patients with aortic stenosis. The ultimate aim is to establish the safety, effectiveness, and appropriate role of BAV therapy as definitive therapy (palliation) or as a "bridge" to surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR).
The objectives of the proposed research are to quantify the impact on motor performance of a single SM intervention on surgical waitlist patients with degenerative Lumbar Spinal Stenosis (LSS) using a recently established lower extremity movement task: 1) using alterable levels of task difficulty that is resistant to learning and 2) using measurement of movement kinematics.