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.

• 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

Patients referred for surgery for aortic valve disease (aortic stenosis group) and those referred for non-aortic valve cardiac surgery or elective ascending aorta surgery (control group)