View clinical trials related to Aortic Valve Stenosis.
Filter by:In the past years a substantial shift away from mechanical heart valves occurred and bioprosthetic heart valves claimed majority of market shares irrespective of patients' age.This indicates that population with failed surgical bioprostheses requiring ViV-TAVI will grow significantly and therefore, meticulous prospective data collection is necessary for future analyses in order to better understand potential limitations of this procedure.
Transcatheter aortic valve implantation (TAVI) is valuable treatment option for patients, who are at the high risk of surgical aortic valve replacement (AVR). Majority of procedures are performed through femoral arteries, however in some this access cannot be applied. Common carotid artery is one of the alternative routes of delivering the device in those patients. Established registry aims at collecting the data prospectively to assess outcomes of TAVI through common carotid artery.
The aim of this study is to compare the clinical outcome of patients with severe aortic valve stenosis and associated significant coronary artery disease treated with TAVI and a percutaneous myocardial revascularization dictated according to two different strategies: 1. the Angiographically-guided strategy; 2. the Physiologically-guided strategy.
Aortic stenosis is the most common valve disease requiring surgery in the Western world. It is defined by progressive calcification and fibrosis of the valve leaflets and restricted valve opening. This in turn exposes the heart muscle (left ventricle) to increasing pressure leading to heart muscle thickening (left ventricular hypertrophy, LVH) to normalise wall stress and maintain heart output (stroke volume). The only treatment available is relief of pressure overload by surgical or minimally invasive valve replacement (TAVI). Transthyretin (TTR) amyloidosis is a condition characterised by deposition of insoluble transthyretin protein (a small protein tetramer produced in the liver) in various tissues, predominantly in the heart. Although there are inherited forms caused by specific TTR gene mutations, most cases occur in older individuals with non-mutated TTR (wild-type). The finding of TTR plaques in elderly individuals is relatively common; in a post-mortem study 22-25% of patients over the age of 80 had evidence of cardiac amyloid deposition. However, there is significant progressive amyloid accumulation in a small percentage of individuals leading to heart muscle thickening and heart failure. No medical treatments are currently licensed although several agents are at advanced stages of clinical trials. As both the above conditions are increasingly common in the elderly population and characterised by increased heart muscle thickening, there is the potential for them to coexist unrecognised in individual patients. The prevalence of cardiac amyloidosis in clinical populations with significant aortic stenosis is not known however small series have estimated somewhere in the region of 6-29%. Other data have suggested that patients with aortic stenosis and concurrent cardiac amyloidosis have an adverse prognosis even despite AVR. It is therefore important to identify aortic stenosis patients with coexistent amyloidosis both in terms of predicting prognosis and because it may influence decisions about whether to proceed to valve intervention. PET/MR is an emerging technique, which combines the excellent temporal and spatial resolution of MRI with the sensitive molecular imaging of PET. PET/MR has significant advantages over PET/CT (the currently more widely used approach) in that it offers superior tissue characterisation, improved correction for cardiac and respiratory motion and major reductions in radiation exposure. Whilst there are concerns about its ability to provide reliable attenuation correction of the PET data, these issues appear to have been largely overcome with recent techniques proposed by our group. MR is also more naturally suited to the imaging of certain tissues in the body compared to CT including the left ventricular myocardium. In aortic stenosis, MRI has become the gold-standard technique for examining the heart muscle (myocardium) with the unique ability to assess its tissue composition. In particular both late gadolinium enhancement (LGE) and T1 mapping based techniques are able to detect heart scarring (fibrosis) which act as biomarkers of left ventricular decompensation and are strongly associated with poor patient outcomes. CMR is also the gold-standard non-invasive technique for detecting cardiac amyloid, which is associated with both a characteristic pattern of LGE and high native T1 values. However it is not currently able to differentiate between the two different types of cardiac amyloid TTR and AL amyloidosis, which have different prognoses and treatments. Preliminary studies conducted by our group have suggested that 18F-NaF PET when added to CMR can make this distinction on the basis that this tracer binds to TTR deposits but not AL deposits, may be able to differentiate between the two. Importantly we have also used the same PET tracer as a marker of calcification activity in the aortic valve, demonstrating its ability to predict disease progression and cardiac events. In this study, we will investigate whether PET/MR could be used as "one-stop" imaging in aortic stenosis in whom valve intervention is being considered to assess in detail functional and structural properties of both the valve and myocardium and identify cases of significant cardiac TTR amyloid deposition.
Severe aortic stenosis remains a major cause of morbidity and mortality of the elderly affecting approximately 3% of elderly patients with an increasing number of patients undergoing transcatheter aortic valve interventions. As part of pre-procedural planning these patients undergo CT scans and receive contrast during the procedure. These patients often have baseline renal insufficiency and are high risk of contrast induced nephropathy despite pre-hydration techniques. The purpose of this study is to evaluate the efficacy of this simple and safe procedure in preventing renal injury in this particular population.
Although aortic valve replacement is recommended for any symptomatic severe calcific aortic stenosis, the therapeutic decision may be difficult. because of patient age and comorbidities. Transcatheter Aortic Valve Implantation (TAVI) has recently extended the therapeutic indications in patients at high risk of surgery. However, the proportion of different treatments is not known in a contemporary population that can be treated according to the different resources currently available. The scientific goal of this observational research is to evaluate intra-hospital therapeutic decision in elderly patients referred because of symptomatic severe aortic stenosis. The one-year survival will be analyzed according to the therapeutic decision and the characteristics of the patients.
The purpose of this study is to confirm if myocardial protection effect can be obtained by intravenous administration of glutamine in patients undergoing aortic valve replacement with severe aortic stenosis (who are at high risk for ischemia-reperfusion injury). As a prospective double blinded randomized placebo-controlled trial, the investigators detect and compare the degree of myocardial damage(with CK-MB and Troponin T) and myocardial protection (through hsp 70 expression in atrial tissue), cardiovascular index, inflammatory reaction, and clinical manifestation.
Aortic stenosis is the most common heart valve disease requiring intervention in high income countries. It is characterised by progressive valvular thickening, and restriction as well is hypertrophy and fibrosis of the left ventricle in response to pressure overload. The pathological processes in the left ventricle that ultimately result in heart failure and death are incompletely understood. Further elucidation of these processes and how they correlate with novel blood biomarkers may help us design new treatments and optimise the timing of surgical intervention. In brief, recruited patients with severe aortic stenosis and scheduled to undergo valve replacement surgery will be invited for some simple tests (blood sampling, ECG, echocardiogram). A septal myocardial biopsy will be taken at the time of surgery and the disease valve retained. These will be examined histologically and pathological changes compared with results obtained from ECG, echocardiogram and blood tests.
This is a prospctive, unrandomized multicentric registry which will enrol patients with an indication for aortc valve replacement combined with myocardial reperfusion (CABG). The registry will collect patient specific baseline data and established risk scores (Logistic Euroscore I & II, STS-Score, KBA Score) to enable us to make an estimate about the perioperative risks.
The PROTEMBO SF Trial is a prospective, observational, multi-center, intention-to-treat study of the safety and feasibility of the ProtEmbo Cerebral Protection System in subjects with severe symptomatic native aortic valve stenosis indicated for TAVR.