Role of Elastin Metabolites in Aortic Remodelling in AS
Role of Elastin Metabolites in Aortic Remodelling in AS
Around 1-2% of people are born with a 'bicuspid' aortic valve, with only two cusps instead of
 the common 'tri-leaflet' valve. People with this valve develop dysfunction of the valve
 (narrowing or leakage) at a much earlier age. It is also more common for them to develop
 enlargement of the main blood vessel coming out of the heart, the aorta, and some studies
 suggest that they are also at higher risk of life-threatening tears in the aortic wall.
 Current guidelines recommend surgical replacement of the aorta at an earlier stage in these
 patients. The exact mechanism for the dilatation is not clear, and some studies have
 suggested greater 'stiffness' in the wall of the aorta. In this study, the investigators
 propose to 1.) study aortic size, stiffness and flow patterns using MRI in patients with
 bicuspid and tricuspid valves with a narrowing (aortic stenosis, 2.) measure markers in
 patients' blood that may be important in the process of expansion, 3.) compare the change in
 MRI and blood markers at before and 12 months after surgery, in patients who are due to have
 aortic valve replacement surgery.
Inclusion Criteria:

 -  Participant is willing and able to give informed consent for participation in the
 study.

 -  Age 18 years or above.

 -  Planned surgical AVR (+/- CABG or aortic root surgery) for severe AS.

 -  Ability to understand the written information in English.

 Exclusion Criteria:

 The participant may not enter the study if ANY of the following apply:

 -  Contraindication to MRI (e.g., non-compatible pacemaker or other device).

 -  Severe claustrophobia (unable to have MRI scan).

 -  eGFR<30ml/min (contra-indication to have contrast agent during MRI).

 -  Contraindication to Adenosine (severe asthma).

 -  Significant arrhythmia.

 -  Other valve disease > moderate in severity.

 -  Female participants who are pregnant or lactating.

 -  Previous aortic valve or aorta surgery, previous CABG or other surgery involving
 aortic cross clamping.

 -  Participant in an interventional cardiovascular clinical trial.