Active clinical trials for "Aortic Valve Stenosis"

This project will evaluate the impact of a patient decision aid created by the American College of Cardiology for patients considering treatment of aortic stenosis. The decision aid describes surgical aortic valve replacement (SAVR) surgery and transcatheter valve replacement surgery (TAVR).

Background and Project Rationale: Degenerative aortic valve stenosis affects 2% of the elderly population aged 70 years or older and progresses insidiously with advancing age [1] before manifesting with symptoms such as decreased exercise tolerance, shortness of breath, chest pain and syncope on exertion. Without aortic valve replacement, the survival prognosis of patients with symptomatic aortic stenosis is poor. In the PARTNER 1B trial, all-cause mortality among 179 inoperable patients with severe symptomatic aortic stenosis allocated to conservative management amounted to 51% at one year [2]. Consistently, prospective registry data reported a mortality rate of 55% at 1 year in 78 patients with severe aortic stenosis undergoing conservative management [3]. The rapid spread of the SARS-CoV-2 pandemic represents an unprecedented challenge for healthcare systems. A limited number of ventilators and ICU beds call for a careful allocation of healthcare resources. On March 20 2020, the Federal Council prohibited elective interventions in all hospitals in Switzerland. Patients with untreated severe aortic stenosis are particularly vulnerable to SARS-CoV-2 infection [4] and face the dual risk of cardiac death from aortic stenosis on one side, and death from acute respiratory distress syndrome secondary to SARS-CoV-2 infection on the other. While the balance between the two risks is a matter of clinical judgement, the investigators established an algorithm for the management of patients with severe aortic stenosis during the SARS-CoV-2 pandemic. Patients with aortic stenosis deemed critical will undergo valvular replacement in spite of the ongoing pandemic while patients with severe but not critical aortic stenosis will undergo deferred intervention once the number of new SARS-CoV-2 infections flattens. In the current situation, aortic valve replacement in patients with severe, non-critical aortic stenosis will be deferred in order to give priority to SARS-CoV-2 patients. This unique situation allows the investigators to study the effect of deferral of aortic valve replacement in patients with severe aortic stenosis. The study is an amendment to the Swiss-TAVI registry. In contrast to the Swiss-TAVI registry, patients are not enrolled at the time of aortic valve replacement, but already at the time of referral for aortic valve replacement. Primary Objective: The aim of the present observational study is to explore the effect of deferral of valvular replacement in patients with severe but not critical aortic stenosis on morbidity and mortality. The primary objective is to describe rates of morbidity and mortality among patients with severe but not critical aortic stenosis in the interval from referral/indication for valvular replacement to intervention. Project Design: The study is a prospective cohort study of patients with severe aortic stenosis referred for aortic valve replacement. All referrals for aortic valve replacement will be allocated to either "transcatheter aortic valve replacement (TAVR)/ surgical aortic valve replacement (SAVR) (standard of care)" or "deferred intervention" based on prespecified criteria. Patients with critical aortic stenosis as defined by an aortic valve area (AVA) <0.6 cm2 or a transvalvular mean gradient of >60 mmHg or a history of cardiac decompensation during the previous 3 months or clinical symptoms on minimal exertion (NYHA III) will be allocated to TAVR or SAVR. All other patients with severe aortic stenosis defined by an AVA <1.0 cm2 will be scheduled for a deferred intervention.

Transcatheter aortic valve implantation (TAVI) has emerged as a valuable minimal-invasive treatment option in patients with symptomatic severe aortic valve (AV) stenosis at prohibitive or increased risk for conventional open-heart surgery. Recent randomized clinical trials reported a large treatment effect of TAVI over medical treatment among inoperable patients and similar or superior outcomes compared with surgical aortic valve replacement in high to intermediate risk patients. However, atrio-ventricular conduction disturbances and arrhythmias (in particular atrial fibrillation) before, during or after TAVI remain a matter of concern as they have important consequences. The objective of this study is to investigate the incidence, nature and prognostic significance of AV-conduction disturbances and arrhythmias among patients with severe, symptomatic aortic stenosis undergoing TAVI before, during and after the procedure using a small implantable cardiac monitoring system (ICM; Medtronic REVEAL LinQTM). One hundred patients will be enrolled in this study. Prior to TAVI (at least 4 weeks), at the time of preprocedural hemodynamic and anatomical assessment, the ICM will be inserted under the skin of the chest under local anesthesia. The device will be interrogated just prior to readmission for TAVI and thereafter at 1, 3, 6, and 12 months of follow-up. The incidence of symptomatic as well as silent brady- and tachyarrhythmias will be recorded, and its impact on medical and device treatment as well as clinical outcomes analyzed. The present study will provide information about the actual incidence and impact of symptomatic and silent arrhythmias and AV-conduction disturbances among patients with severe, symptomatic aortic stenosis undergoing TAVI. Specifically, the study estimate the burden of arrhythmias before TAVI and to accurately determine the incidence of new onset atrial fibrillation and complete AV-block within 12 months after the procedure. Identifying patients at risk for AV- conduction abnormalities, atrial fibrillation (AF), and non-sustained or sustained ventricular arrhythmias may guide future preventive measures, medical treatment and improve patients outcomes after TAVI.

This is an international, mutli-center, prospective, consecutively enrolled, observational registry. 2000 patients are planned to be enrolled over one year at up to 150 participating sites. 300 patients out of the 2000 patients enrolled in the main registry are planned to be consecutively enrolled in a select few sites for studying the valve performance. Echocardiogram and angiogram will be taken routinely.

Aortic stenosis is a major cause of morbidity around the world. Progressive aortic stenosis leads to cardiac hypertrophy as a compensatory response. A maladaptive response may lead to heart failure at varying degrees of severity of aortic stenosis in individual patients. The predicting factors for the occurrence of a maladaptive response are not well defined. Therefore current medical therapy for aortic stenosis is considered insufficient and may actually cause harm. The only effective therapy for severe, symptomatic aortic stenosis is aortic valve replacement. It has been found in an experimental study that Podocan determines the degree of cardiac hypertrophy in response to pressure overload via the Wnt-pathway. The possible prognostic role of secreted circulating Wnt modulators in aortic stenosis has also recently gained attention. This project will attempt to establish the prognostic role of circulatory Podocan and Wnt modulators for maladaptive left ventricular response to aortic stenosis. This may help identify patients at particular risk to develop left ventricular dysfunction with aortic stenosis and improve understanding of the mechanisms of left ventricular remodeling in aortic stenosis. Hence, this may also later act as an important background in finding more effective therapies to prevent or delay maladaptive left ventricular response in aortic stenosis.

The management of symptomatic patients with moderate Aortic Stenosis (AS) remains challenging and tests that would give more definitive answers are needed. The value of increase in Aortic Valve mean Gradient (AVMG), lack of change in Aortic Valve area (AVA) and calculation of valve compliance/resistance during stress echo (SE) in the symptomatic moderate AS population prognostication has to the investigators knowledge not been examined before. Similarly the additive value of myocardial blood flow reserve (MBFR), Computed Tomography (CT) calcium score, speckle tracking echocardiography, carotid ultrasonography, and N-Terminal pro B- type natriuretic peptide B (NT-proBNP) in the prognostication of this population group especially in combination with SE remains unclear.

Post-market registry on ACURATE TA™ Transapical Aortic Bioprosthesis and ACURATE TA™ Delivery System implantation in patients presenting severe symptomatic aortic stenosis to provide safety surveillance of the device.

Current care randomized clinical trial comparing the CE marked Symetis ACURATE neo™ Aortic Bioprosthesis and ACURATE TF™ Transfemoral Delivery System with the CE marked Medtronic CoreValve Evolut R TAVI system (or any future CE-marked CoreValve versions).

The CoreValve ADVANCE-II Study is a best practices investigation of patients implanted with the Medtronic CoreValve bioprosthesis.

The investigators decided to make a study with a cohort of patients as homogenous as possible with a cross clamp time around 70 min. Adult patients with a severe aortic stenoses without any other significant heart disease was included in our prospective randomised study. This group of patients was chosen for two reasons. First, these patients have left ventricular hypertrophy making the myocardium vulnerable to ischemia, secondly the investigators wanted to avoid the possible confounding effect of ischemia found in patients with variable degrees of coronary artery disease. Therefore, patients with additional significant coronary artery disease (≥ 50% stenoses) were excluded from the study.