A Comparison of Advanced Imaging Techniques in Aortic Stenosis

Study Overview
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Brief Summary
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In patients with aortic stenosis the valve through which blood is pumped out of the main heart chamber is narrowed. This results in heart muscle working harder to open the valve so blood can circulate around the body. The muscle adapts to the increased pressure load to maintain efficiency. This can cause long-term muscle damage. To predict when this deterioration will require a valve replacement is difficult and untimely operation exposes patients to unnecessary risk. We aim to compare all validated techniques looking at different aspects of heart muscle strain in these patients. These will be a blood sample measuring a specific hormone (BNP) and enzyme (Troponin), a nuclear scan to assess nerve activation, an MRI identifying scarring and an exercise echocardiogram that measures heart muscle response and pressure changes across the valve. Tests will be performed at recruitment and either after one year or after valve replacement, which ever comes first. In comparing these different imaging techniques we aim to identify patients who will benefit from an early operation, those whose muscle is likely to recover back to normal and which patients it is safe to wait longer for the surgery, avoiding unnecessary risk. The results of the study will benefit patients as it will help doctors more accurately assess the timing of valve surgery and improve their prediction of long term heart muscle recovery. It may also increase convenience in clinical management by reducing unnecessary tests and hospital trips. This would translate into cost savings for the NHS.

Official Title
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A Comparative Study of Advanced Imaging Techniques in Predicting the Clinical Outcome in Aortic Stenosis

Conditions
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Aortic Stenosis

Intervention / Treatment
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* Radiation: Cardiac I123-MIBG Scintigraphy
* Other: Cardiac MRI
* Other: Stress and rest Echocardiogram
* Other: High Sensitivity Troponin I
* Other: Brain Natriuretic Peptide


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: (Group A) Asymptomatic patients with moderate to severe Aortic Stenosis Ejection fraction greater than 50% Not yet being considered for valve surgery (Group B) Severe Aortic Stenosis (as per ESC guidelines) Listed for immediate aortic valve replacement Exclusion Criteria: (Group A and B) Inability to provide informed consent Concurrent primary valve lesions greater than mild (as defined by ESC criteria) Previous myocardial infarction (regional wall motion abnormality on resting echo) Cardiomyopathy Congenital heart disease Previous cardiac surgery Renal failure (CKD stage 3, eGFR >30ml/min/1.73m2) Pregnancy, risk of pregnancy, breast feeding

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| A - Symptomatic severe AS<br>Patients with symptomatic severe aortic stenosis (AS) as per ESC guidelines, requiring aortic valve replacement. | Radiation: Cardiac I123-MIBG Scintigraphy<br> <br> Other: Cardiac MRI<br> <br> Other: Stress and rest Echocardiogram<br> <br> Other: High Sensitivity Troponin I<br> <br> Other: Brain Natriuretic Peptide<br> <br> |
| B - Asymptomatic moderate to severe AS<br>Asymptomatic patients with moderate to severe aortic stenosis (AS) as per ESC guidelines ,with Left Ventricular ejection fraction >50%, not yet requiring aortic valve replacement. | Radiation: Cardiac I123-MIBG Scintigraphy<br> <br> Other: Cardiac MRI<br> <br> Other: Stress and rest Echocardiogram<br> <br> Other: High Sensitivity Troponin I<br> <br> Other: Brain Natriuretic Peptide<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Need for aortic valve replacement |  | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Improvement in measured indices post aortic valve replacement |  | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Left Ventricular Function, Aortic Valve Replacement, Late Gadolinium Enhancement, Cardiac I123 MIBG, Longitudinal Strain, Brain Natriuretic Peptide, High Sensitivity Troponin I