Studying human coronary microvascular function
Research type
Research Study
Full title
Matching in vivo to ex vivo human coronary microvascular function
IRAS ID
337891
Contact name
Kim Dora
Contact email
Sponsor organisation
Address University of Oxford Research Governance, Ethics & Assurance
Duration of Study in the UK
2 years, 5 months, 31 days
Research summary
Blood flow to the heart muscle is normally regulated by microscopic arteries in the heart. These micro-arteries are able to change their size, either increasing or reducing blood flow to meet the demands of the heart. In many people these micro-arteries are dysfunctional, called “microvascular dysfunction”, leading to symptoms and worse heart outcomes, but very little is known about the mechanisms leading to dysfunction.Microvascular function can be estimated in-vivo using pressure wires in the coronary arteries. However the underlying mechanisms that lead to dysfunction are difficult to explore in detail. The diameter of these micro-arteries is less than 300 μm, below the limits of medical imaging, so studies exploring mechanisms of dysfunction must be performed ex-vivo on micro-arteries dissected form human heart tissue. We have recently shown how to isolate and study these micro-arteries from human right atrial muscle. However it is unclear if our model based on right atrial tissue can be used as a surrogate for the clinically more relevant left ventricle. It is also unclear how our ex-vivo measures of micro-artery function relates to clinically used in-vivo measures.
This project is an observational study in patients who are undergoing mitral valve heart surgery. During their operation surplus right atrial and left ventricular tissue is normally removed and discarded but we will retain this surplus tissue for research.
We can then compare micro-artery function from paired left ventricular and right atrial tissue. We will also compare this to clinical in-vivo measurements of microvascular function obtained in the pre-operative period. This linking of in-vivo and ex-vivo measures of microvascular function will provide important insights into molecular mechanisms leading to microvascular dysfunction. Finally we will use peri-operative blood tests and patient demographic information to look for any correlations between patient risk factors and microvascular function.
REC name
South Central - Oxford B Research Ethics Committee
REC reference
24/SC/0148
Date of REC Opinion
10 Jun 2024
REC opinion
Further Information Favourable Opinion