VIRTU-AS
Research type
Research Study
Full title
The (virtual) assessment of coronary blood flow before and after treatment of severe aortic stenosis.
IRAS ID
301021
Contact name
Julian Gunn
Contact email
Sponsor organisation
Sheffield Teaching Hospitals NHS Foundation Trust
Duration of Study in the UK
2 years, 6 months, 6 days
Research summary
Summary of Research
The aortic valve allows blood out of the heart. Patients with a narrowed valve (aortic stenosis, AS) can also develop narrowed arteries in the heart (coronary artery disease, CAD). It is hard to know whether to treat CAD in patients with AS, because AS can change the flow through the arteries, and treating the AS with a new valve (Transcatheter aortic valve implantation - TAVI) could reverse some of the changes. The accepted standards for treating CAD may therefore not apply in AS. We have developed a computer model of the circulation, and plan to adapt this to solve this problem. To do this, we will study patients who have AS and are being considered for treatment with TAVI. We will obtain data about their symptoms and quality of life with questionnaires, measure their activity levels with wearable technology and perform a simple walking test. The measurement of activity levels and questionnaires will be performed at the patients’ homes, the walk test at the pre-admission clinic, and the invasive procedures at the cardiac catheter laboratories of the Northern General Hospital, Sheffield. We will also perform a cardiac MRI before and after TAVI. We will then measure the blood flow down their coronary arteries using a tube in the circulation (this is a standard clinically approved method) before and after TAVI. We will repeat the questionnaires, activity monitoring, MRI and blood flow measurements some months later.
This study is funded by the Heart Trust Charity Fund and Sheffield Hospitals Charity and will recruit 20 elective patients attending Sheffield Teaching Hospitals (STH) and referred to STH from District General Hospitals.Summary of Results
Measuring blood flow in the coronary arteries before and after treatment of aortic stenosis with a minimally invasive method of aortic valve replacement (TAVI) was a useful investigation because it allowed us to differentiate the positive effects of TAVI from coronary artery disease/stenting. We found that treatment with TAVI provides significant improvement in coronary artery blood flow regardless of the degree of coronary artery narrowing or treatment with conventional stenting procedures. This means that conventional wisdom of treating coronary arteries with stenting prior to treatment of the aortic valve with TAVI, may not in fact be necessary, and treatment of the valve in isolation may be enough to promote positive effects at the heart muscle and artery level. This requires more investigation and research to be definitive, but if true, it would help to save patient time, medication requirements, risk and procedure numbers.REC name
North West - Preston Research Ethics Committee
REC reference
22/NW/0017
Date of REC Opinion
8 Feb 2022
REC opinion
Favourable Opinion