Mechanism of Decompensation Evaluation - Aortic Stenosis

Study Overview
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Brief Summary
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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.

Official Title
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Mechanism of Left Ventricular Decompensation Evaluation - Aortic Stenosis

Conditions
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Left Ventricular Hypertrophy, Aortic Stenosis, Myocardial Fibrosis

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria (aortic stenosis group): Age over 18 Severe aortic stenosis with planned aortic valve replacement Inclusion Criteria (control group): Age over 18 Planned non-aortic valve cardiac or elective ascending aorta surgery Exclusion Criteria (aortic stenosis group): Coexistent severe aortic or mitral regurgitation Coexistent mitral stenosis greater than mild in severity Acute valvular heart disease (e.g. acute mitral regurgitation or endocarditis) Acute pulmonary oedema or cardiogenic shock Coexistent hypertrophic cardiomyopathy Unable to give informed consent Exclusion Criteria (control group): Significant aortic valve disease (mild aortic stenosis / regurgitation or greater) Acute valvular heart disease (e.g. acute mitral regurgitation or endocarditis) Acute pulmonary oedema or cardiogenic shock Coexistent hypertrophic cardiomyopathy Unable to give informed consent

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 |
| --- | --- |
| Severe aortic stenosis<br>Patients with severe aortic stenosis who are scheduled to undergo aortic valve replacement surgery | |
| Control group<br>Patients scheduled to undergo non-aortic valve cardiac or elective ascending aortic surgery | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation of blood biomarkers with pathological changes on myocardial biopsy | Correlation between biomarkers (e.g. high sensitivity troponin I, BNP) with levels of myocardial fibrosis (collagen volume fraction as measured by picrosirius red staining) | Biomarkers collected within 1 month prior to date of surgery (and myocardial biopsy) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation of echocardiographic and ECG measures with pathological changes on myocardial biopsy | Correlation between imaging measures (e.g. LV diastolic function, longitudinal systolic function, ECG LVH criteria, ECG strain pattern) with levels of myocardial fibrosis (collagen volume fraction as measured by picrosirius red staining) | Biomarkers collected within 1 month prior to date of surgery (and myocardial biopsy) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Troponin