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Active clinical trials for "Aortic Valve Stenosis"

Results 751-760 of 802

Prevalence and Significance of Mutations in Genes Encoding NaPi-co-transporters in the Development...

Aortic Valve CalcificationAortic Stenosis

Mutations in the SLC34A2 gene, that encodes the sodium phosphate co-transporter (NaPi-IIb), cause defect cell-uptake of phosphate, which leads to formation of calcium-phosphate concretions in the lungs as seen in Pulmonary Alveolar Microlithiasis (PAM). Extra pulmonary calcifications, including heart valve calcification, have previously been reported in patients with PAM. Calcific Aortic Valve Disease (CAVD) is a common disease in the elderly and is characterised by thickening and calcification of the aortic valve leaflets in the absence of rheumatic heart disease. CAVD is present in more than 25% of patients older than age 65 years and is associated with an increased risk of cardiovascular events. Currently, there is no effective therapy for the disease other than surgical aortic valve replacement. Both calcium and phosphate are the major components of calcific deposits in PAM and CAVD. Based on these preliminary findings, the investigators hypothesize that mutations in sodium phosphate co-transporters may play a role in both pulmonary and extra pulmonary calcifications. Two studies will be performed: 1. A retrospective cross-sectional study including patients with an age ≤ 65 years with CAVD from Denmark and Örebro, will be carried out. Genetic association analysis will be performed to investigate the incidence of common variants in five genes representing sodium phosphate co-transporters (SLC34A1, SLC34A2, SLC34A3, SLC20A1, SLC20A2) compared to healthy controls. Associated genes will subsequently be sequenced to identify possible causal mutations. 2. In a prospective study, aortic valve tissue will be collected from patients with AS undergoing surgical valve replacement. Molecular characterisation of the transporters will be conducted by determining the level of specific mRNA and protein by RT-PCR/qPCR, and Western Blotting, respectively. The localisation and visualisation will be investigated by immunostaining and confocal laser microscopy. Fibroblasts and endothelial cells will be isolated and grown in cultures with subsequent functional studies of the phosphate uptake.

Unknown status6 enrollment criteria

Identification of Parameters in rapId-proGression Subgroup Patients With Moderate Aortic Stenosis...

Aortic Stenosis

The investigators aim to identify all clinical, biological, echo and imagistic parameters that predispose to increased progression rates in a prospective observational trial which will include ONLY patients with moderate AS, with the complete cardiological investigational tools provided in 2012. Once those parameters are found, medical and interventional treatment could be implemented to decrease the mortality rates.

Unknown status21 enrollment criteria

Clinical and Geriatric Assessment in Elderly Patients Before and After TAVI or MitraClip Positioning...

Mitral Valve InsufficiencyAortic Stenosis Senile

Since October of 2014, the Policlinico Umberto I Hospital has an "Heart Team", a group of selected specialists with the task of assessing and identifying eligible patients for valvular aortic transcatheter implantation (TAVI) or a placement of a MitraClip . The specialists taking part to Heart Team are: a cardiologist, a heart surgeon, a vascular surgeon, an anesthesiologist and a geriatrician. The Geriatrician is called to make a careful multidimensional assessment of the elderly patients who have been suggested for the interventions mentioned above. His role is to assess the degree of co-morbidity and polypathology, autonomy in the common activities of daily living, nutritional status, cognitive status and quality of life. Following this evaluation, together with the other components of Heart Team, it is expressed a collective judgment on the patient's eligibility to these interventions. So, the aim of the present study is to identify changes in the degree of cognitive decline, of autonomy in carrying out activities of daily living, quality of life, nutritional status, pre- and postoperatively (6 months after the procedure) polypathology degree in elderly patients to be undergone or undergoing TAVI or positioning MitraClip because suffering from aortic valvular stenosis or severe mitral insufficiency. The patients undergo to a battery of tests, to a 5 minutes electrocardiographic record to evaluate the Heart Rate Variability (HRV) and to a complete echocardiographic evaluation.

Unknown status7 enrollment criteria

Vascular Closure Device in Transcatheter Aortic Valve Replacement

Aortic Valve Stenosis

Evaluation of the safety and efficacy of a percutaneous plug-based large-bore vascular closure device for femoral artery closure in an unselected consecutive patient cohort undergoing transcatheter aortic valve implantation in a single-center prospective study.

Unknown status3 enrollment criteria

Water- and Salt-homeostasis in Healthy Humans, and in Patients With Heart- or Lung Disease

Healthy VolunteersHeart Failure3 more

The purpose of the study is to determine whether the excretion of renal water- and salt-channels in the urine reflects the handling of water and salt in the kidneys, and whether the excretion can be used to monitor and/or predict the effects of treatment of certain heart or lung diseases.

Unknown status8 enrollment criteria

Role of Elastin Metabolites in Aortic Remodelling in AS

Aortic Stenosis

Around 1-2% of people are born with a 'bicuspid' aortic valve, with only two cusps instead of the common 'tri-leaflet' valve. People with this valve develop dysfunction of the valve (narrowing or leakage) at a much earlier age. It is also more common for them to develop enlargement of the main blood vessel coming out of the heart, the aorta, and some studies suggest that they are also at higher risk of life-threatening tears in the aortic wall. Current guidelines recommend surgical replacement of the aorta at an earlier stage in these patients. The exact mechanism for the dilatation is not clear, and some studies have suggested greater 'stiffness' in the wall of the aorta. In this study, the investigators propose to 1.) study aortic size, stiffness and flow patterns using MRI in patients with bicuspid and tricuspid valves with a narrowing (aortic stenosis, 2.) measure markers in patients' blood that may be important in the process of expansion, 3.) compare the change in MRI and blood markers at before and 12 months after surgery, in patients who are due to have aortic valve replacement surgery.

Unknown status14 enrollment criteria

Change in Coronary Microcirculation and FFR After TAVI in Patients With Cardiovascular Comorbidities...

Severe Symptomatic Aortic Stenosis

Change in coronary microcirculation and Fractional Flow Reserve after Transcatheter Aortic Valve Implantation in patients with concomitant coronary artery disease and severe aortic stenosis. Severe aortic stenosis is the most common indication of valvular replacement in developed countries. Stable coronary artery disease (CAD) is frequently associated with severe aortic stenosis in patients treated by Transcatheter Aortic Valvular Implantation (TAVI). Its prognostic impact is not clearly established, and available studies uncommonly used functional assessment of severity from a coronary stenosis to stratify the risk in this situation. Fractional Flow Reserve (FFR) is recommended to guide revascularization by percutaneous coronary intervention (PCI) in clinical practice. Its use is not validated in patients with severe aortic stenosis. Left ventricular hypertrophy induced by aortic obstruction leading to microvascular disorders, and can alter coronary reserve, possibly biasing FFR values. After aortic valvular replacement, a myocardial reverse remodeling is described, generating a decrease in hypertrophy, interstitial oedema, and inflammation. Its effect on coronary microcirculatory reserve is not known. Some studies have shown improvement in coronary reserve immediately after TAVI and this effect seemed to last long after treatment. The aim of the study is to assess the effects of inverse myocardial remodeling on coronary microcirculatory function and its association with FFR values before and after TAVI.

Unknown status9 enrollment criteria

Type II Diabetes Influence on Left Ventricular Remodeling and Outcomes in Patients Undergoing Aortic...

Type II Diabetes

This project focuses on the physiopathology of left ventricular remodeling associated with type II diabetes in patients with aortic valve stenosis referred for surgical aortic valve replacement. The main objective is to compare the reverse left ventricular remodeling between patients with type II diabetes and case-control patients without diabetes at one(1) year after surgical aortic valve replacement. The secondary objectives are : assess the influence of type II diabetes on left ventricular remodeling in patients presenting with aortic valve stenosis, assess the predictive value of myocardial fibrosis and other LV characteristics present prior to aortic valve surgery on the LV reverse remodeling and their influence on cardiovascular events at one (1) year after surgery, assess the influence of type II diabetes on cardiovascular morbidity and mortality post aortic valve surgery. The investigators main hypothesis is that patients with type II diabetes and aortic valve stenosis requiring aortic valve replacement have poorer LV function and less favorable post surgery clinical outcomes than patients without type II diabetes.

Unknown status17 enrollment criteria

A Registry to Evaluate the Direct Flow Medical Transcatheter Aortic Valve System

Aortic Valve Stenosis

The purpose of this postmarket Registry is to assess the standard of care and clinical outcomes of the Direct Flow Medical Transcatheter Aortic Valve System used in clinical routine according to the approved commercial indications. Procedures and assessments required by this registry are generally considered standard of care for Transcatheter Aortic Valve Replacement patients. Evaluation criteria will be the incidence of mortality/morbidity and adverse events clinical performance, and hemodynamic performance of the DEVICE via ultrasound (echo) and angiographic imaging.

Unknown status8 enrollment criteria

Determination of the Acute Effects of Aortic Stenosis on Coronary Artery Haemodynamics

Aortic Valve Stenosis

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.

Unknown status8 enrollment criteria
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