Prevalence of Transthyretin Cardiac Amyloidosis in Clinically Significant Aortic Stenosis
Aortic StenosisTransthyretin Amyloidosis2 moreThe purpose of this study is to determine the prevalence of transthyretin cardiac amyloidosis (TTR-CA) among patients with moderate and severe aortic stenosis in Southeast Minnesota using 99mTc-PYP single-photon positive emission computed tomography with computed tomography (SPECT/CT).
On Dose Efficiency of Modern CT-scanners in Chest Scans
PneumoniaLung Cancer3 moreCT scans of the chest / thorax are of great importance both in the initial diagnosis and in the follow-up of pulmonary or thoracic diseases. As an example, CT angiography of the pulmonary arteries (CTPA) is worldwide considered to be gold standard test in patients with a suspicion for pulmonary embolism. The aim of this study is to measure and compare dose efficiency of modern CT scanners for unenhanced and contrast-enhanced scan protocols of the chest/thorax. Patients who are referred for a CT of the chest/thorax will be randomly assigned to one of the three CT scanners currently in use at our institution.
The Effect of Remote Ischemic Preconditioning in Aortic Valve Replacement Surgery
Aortic Valve StenosisCardiopulmonary BypassThe study objective is to verify if a non-invasive remote ischemic preconditioning procedure (blood pressure cuff on the arm) is cardioprotective when applied before an aortic valve replacement surgery.
Early Valve Replacement Guided by Biomarkers of LV Decompensation in Asymptomatic Patients With...
Aortic Valve StenosisHypertrophy1 moreAortic stenosis is the most common valvular disease in the Western world. It is caused by progressive narrowing of the aortic valve leading to increased strain on the heart muscle which has to work increasingly hard to pump blood through the narrowed valve. Over time the heart muscle thickens to generate more force, but eventually the heart fails leading to death if the valve is not replaced with an operation. No medical treatments exist to stop or reverse the heart valve narrowing. Current clinical guidelines suggest that an operation should be performed only when symptoms develop or the heart muscle is visibly weak on cardiac ultrasound scanning. However, symptoms can be difficult to interpret and in many patients the heart muscle has become irreversibly damaged and the heart fails to recover following surgery. Using MRI scans of the heart, the investigators have identified heart scarring which seems to develop as the heart muscle thickens. Several studies now show that people who have developed this scarring are more likely to suffer poor outcomes including death. The investigators have also identified clinical risks that predict the presence of scarring. The investigators propose a study where patients with severe aortic stenosis but no indications for valve replacement as per current guidelines are assessed for those clinical risks. If a participant's risk of having scarring is higher they will undergo a cardiac MRI scan. If scarring is present participants will be randomised to routine clinical care, or referral for valve replacement surgery. Participants with no evidence of scarring will be randomised routine care with study follow or not. The investigators of this study hypothesize that early surgery will lead to fewer complications and reduced risk of death compared to standard care.
The Nordic Aortic Valve Intervention Trial
Critical Aortic StenosisA randomized clinical trial of transcatheter aortic valve implantation (TAVI) versus conventional surgical aortic valve replacement (SAVR) in patients older than 70 years of age suffering from severe aortic valve stenosis. Study hypothesis: TAVI will reduce post-interventional morbidity and mortality compared to SAVR.
Strategies to Prevent Transcatheter Heart Valve Dysfunction in Low Risk Transcatheter Aortic Valve...
Aortic Stenosis100 subjects in the each of the treatment arms of the study (total 200 treatment arm subjects) and up to 100 subjects in the registry arm of the study.
Imaging Histone Deacetylase in the Heart
Heart Failure With Normal Ejection FractionLeft Ventricular Hypertrophy2 moreThe overall goal of this PET-MR imaging trial is to evaluate 11C-Martinostat, a histone deacetylase targeted radioligand, in patients with aortic stenosis, individuals with diabetes, and healthy volunteers.
The HALT Biomarker Study
Aortic StenosisHypo-attenuated Leaflet Thickening1 moreThe purpose of the HALT Biomarkers study are to identify a panel of circulating proteins that discriminates between patients with and without Hypo-Attenuated Leaflet Thickening (HALT) and can be used to supplement the diagnosis of HALT; to characterize changes in circulating proteins after treatment of HALT with systemic anticoagulation; and to identify circulating proteins that predict the occurrence of HALT. The study population will be adult patients undergoing transfemoral transcatheter aortic valve replacement (TAVR) for severe aortic stenosis (AS) or bioprosthetic valve degeneration. Enrollment will continue until 30 patients with HALT are identified for completion of phase 1. Based on a HALT incidence rate of 10%, we anticipate enrolling 300 patients. Patients are enrolled prior to undergoing transfemoral TAVR. Blood samples, clinical data and echocardiograms will be collected at the following timepoints: baseline (pre-TAVR, T0), post-TAVR (pre-discharge, T1), 30-day follow-up (window 3-9 weeks, T2), and 6-month follow-up (T3). Cardiac 4D CT will be performed at the 30-day follow-up visit to screen for the occurrence of HALT. Patients with HALT will be treated with systemic anticoagulation for 5-6 months, at which point a follow-up CT scan and blood sample will be obtained. Control subjects will also undergo a 6-month study visit with blood sample collection. The study will be conducted within two phases. Phase 1 will serve as a derivation / discovery study in which candidate protein biomarkers of HALT will be identified. Once this is successfully completed, a second cohort will be enrolled within phase 2. Phase 2 will be performed under the auspices a future contract or amendment and will seek to cross-validate the initial study findings.
A Study to Evaluate a Computerized Stethoscope Called ©Voqx to Diagnose Heart Disease
Isolated Aortic StenosisMitral RegurgitationThe purpose of this study is to determine whether recording heart sounds with an acoustic stethoscope, combined with artificial intelligence (computer information), will show similar abnormalities to an echocardiogram or cardiac catheterization.
Predictive Value of Pre-TAVI Infrahissian Conduction Time in the Occurrence of Complete Atrioventricular...
Aortic StenosisSevereThe purpose of the study is implantation of a Pacemaker at 30 days for occurrence of a high-grade conduction disorder per- or post-procedure (yes/no)