View clinical trials related to Constriction, Pathologic.
Filter by:The purpose of the study is to prospectively assess the use of a modified tracheal balloon dilator in children (<13 years old) with subglottic or tracheal stenosis. The hypothesis is that the device will effectively dilate the stenotic segment, whilst maintaining oxygenation (if applicable). The primary aim is to measure the stenosis prior to, and after dilatation; using diameter and the modified Myer-Cotton grading system. Secondary aims include assessment of stenosis at six-week follow-up and monitoring arterial oxygenation nadir (using peripheral plethysmography) during the procedure.
Aortic stenosis (AS) is the most frequent valvulopathy in Western countries. The prevalence of AS is constantly increasing due to the aging of the population. Although significant progress has been made in understanding the pathophysiological mechanisms underlying the onset and progression of AS, there is no medical treatment to slow or prevent its progression. The only treatment available is Aortic Valve Replacement (AVR) performed by surgery or by catheterization (TAVI). AS is associated with an increase of post-load which leads the left ventricular myocardium to hypertrophy. Associated with hypertrophy, myocardial fibrosis will gradually develop. Despite interesting data, many unknowns persist and remain to be identified. The aim of the study is to evaluate prospectively the progression and impact of AS in 500 patients using clinical, biological, echocardiographic and MRI parameters performed annually.
Aortic stenosis (AS) is the most frequent valvulopathy in Western countries. The prevalence of AS is constantly increasing due to the aging of the population. Although significant progress has been made in understanding the pathophysiological mechanisms underlying the onset and progression of AS, there is no medical treatment to slow or prevent its progression. The only treatment available is Aortic Valve Replacement (AVR) performed by surgery or by catheterization (TAVI). AS is associated with an increase of post-load which leads the left ventricular myocardium to hypertrophy. Associated with hypertrophy, myocardial fibrosis will gradually develop. Despite interesting data, many unknowns persist and remain to be identified. The aim of the study is to characterize prospectively the left ventricular remodeling and assess its changes after AVR and within 1 year in 500 patients using clinical, biological, echocardiographic and MRI parameters.
Lumbar spinal stenosis (LSS) is a common spinal disease that leads to pain and disability. LSS is defined as lower extremity and perineal symptoms (e.g. intermittent neurogenic claudication/numbness) that may occur with or without low back pain and that is attributed to congenital or acquired narrowing of space available for the neural and vascular tissues in the lumbar spine. Patients with LSS,who do not respond to conservative treatments after 3 months or more, will be eligible for spinal decompression surgery in order to improve functional outcomes. While various studies have shown that preoperative exercises (prehabilitation) may benefit patients receiving different surgeries (e.g, abdominal surgery, anterior cruciate ligament reconstruction), little is known regarding the effect of prehabilitation for patients undergoing LSS surgery. The aim of the current randomized controlled trial is to compare the effectiveness of a 6-week prehabilitation program with usual preoperative care in improving multiple outcomes of patients undergoing LSS surgery at baseline, 6 weeks after baseline evaluation, and at 3 and 6 months postoperatively. It is hypothesized that prehabilitation will yield significantly better pre- and post-operative clinical outcomes as compared to usual preoperative care.
The purpose of this study was to compare standard open laminectomy with ULBD approach in regard to efficiency, safety, and clinical outcome.
The FinnValve investigators planned a nationwide registry to investigate the early and late outcome of transcatheter aortic valve implantation (TAVI) compared to surgical aortic valve replacement (SAVR) in patients with aortic valve stenosis performed from 2008 to 2017 at five Finnish University Hospitals. Data will be collected in a dedicated electronic case report form.
Calcified aortic stenosis is the most frequent valvulopathy in Europe and North America. Aortic stenosis is an obstacle to the ejection of blood from the left ventricle to the aorta and leads to morphological changes in the left ventricle and hemodynamic modifications. Intrinsic ventricular performance can be characterized using three parameters: - Ventricular elastance (Ees for End Systolic Elastance) which represents the index of ventricular contractility independently of the load. - Arterial elastance (Ea for Arterial Elastance) which represents the post-load - The ventriculo-arterial coupling index (Ees / Ea) which represents energy efficiency. For patients with high surgical risk (EuroSCORE II> 6), TAVI (Transcatheter Aortic Valve Implantation) is recommended for aortic valve replacement. Many complications may occur after TAVI (haemorrhagic, embolic, renal, myocardial ischemia). Post-TAVI complications may also be cardiac decompensation of the underlying cardiac disease to cardiogenic shock. However, literature on left ventricular performance after aortic valvular replacement is poor because of the difficulty and invasiveness of the analysis involved. Cardiac energy analysis plays an additional role in understanding the clinical patients conditions. On this point, cardiac energy modifications, based on ventriculo-arterial coupling, could be indicators of cardiac function. Two methods (ultrasound and pulse contour) are used to understand and explore the ventriculo-arterial coupling, preload, postload, contractility and hemodynamic changes interactions. Echocardiography allows the Ees / Ea and SW / PVA (Stoke work/ pressure-volume area) ratios mesurements. PRAM (Pressure Recording Analytical Method) through the MostCare® monitor, gives common hemodynamic parameters and more specific parameters such as arterial elastance (Ea) cardiac cycle efficiency (CCE), dP / dt. Cardiac cycle efficiency (CCE) is an exclusive variable that describes the hemodynamic performance in terms of energy expenditure in the patient being followed. TAVI procedure is an acute model of ventriculo-arterial coupling modification by treatment of the ventricular ejection obstacle. The PRAM method evaluates the ventriculo-arterial coupling. The aim of our study is to evaluate by PRAM the changes in cardiac energy variables before and after aortic valve replacement by TAVI
To date, no formal, randomized, prospective, head-to-head comparisons of surgical aortic valve replacement (SAVR) versus transcatheter aortic valve replacement (TAVR) have been undertaken in the severe aortic stenosis (AS) population with small aortic annuli. Objectives of the present study are to compare the hemodynamic performance (incidence of severe PPM and ≥ moderate AR) and clinical outcomes (death, stroke, major or life threatening bleeding) between TAVR and SAVR in patients with severe AS and small aortic annuli.
Renal artery stenosis is one the leading cause of secondary hypertension. Previous randomized controlled trials in humans have failed to demonstrate an improvement of renal function after stenosis dilation, probably because of a selection bias with more severe patients being excluded from randomization. Renal ischemia-reperfusion injuries have also not been taken into account. Indeed, reperfusion leads to a rapid renal blood flow recovery associated with renal ischemia-reperfusion injuries. Mitochondrial permeability transition pore (mPTP) is a key player in the occurrence of ischemia reperfusion injuries because its opening leads to mitochondria leakage and cell death. However, preconditioning whether pharmacological or ischemic can prevent mPTP opening and protect cells. Ciclosporin A can prolong mPTP closing during reperfusion and reduce renal and cardiac tissular lesions. Another mPTP blocker (Bendavia) has been associated with an improvement of renal blood flow (RBF) and glomerular filtration rate (GFR) after renal artery stenosis dilation at 6 weeks in pigs. Based on a recent study, dilation overall benefit could be secondary to an improvement of the contralateral kidney GFR and tissue oxygen content, requiring a single kidney evaluation of those renal functional parameters. The investigators previously demonstrated that dose and timing of ciclosporin A preconditioning is key to protect kidneys from ischemia-reperfusion injuries. Previous controlled trials that failed to demonstrate a benefit of ciclosporin A conditioning have used post conditioning on necrotic cells. Considering kidney ischemia-reperfusion injuries, preconditioning have led to more encouraging results compared to ciclosporin A post conditioning in animals. Therefore the investigators aim to conduct the first clinical study of ciclosporin A preconditioning for prevention of kidney ischemia-reperfusion injuries after renal artery stenosis dilation. Using renal functional imaging and the new PET-MRI (Positron Emission Tomography-Magnetic Resonance Imaging) combined device, the investigators will evaluate kidney perfusion, oxidative metabolism, glomerular filtration rate and oxygen content before and 3 months after renal artery stenosis dilation with or without a ciclosporin A preconditioning.
This is a pivotal Randomized Clinical trial to compare the safety and effectiveness of the Pedicle Lengthening Osteotomy Procedure with implantation of the Altum® Device to open surgical decompression and Transforaminal Lumbar Interbody Fusion (TLIF) in patients with symptomatic, one or two level lumbar spinal stenosis (LSS) and one level grade I degenerative spondylolisthesis requiring surgical treatment.