Studies of the Vascular Properties of Bypass Grafts
The inner lining of a person’s arteries are made up of cells (specifically endothelial cells) that can control how the artery stretches or dilates. The measure of how well this mechanism works is called “endothelial function”. The term “endothelial dysfunction” is used to describe changes in the in the inner lining of the artery to a state that can lead to disease progression and atherosclerosis.
This study invited patients undergoing coronary artery bypass graft surgery at the John Radcliffe Hospital to participate in further investigation of their endothelial function to help better understand why some bypass grafts work better than others and how the function of them could possibly be improved in the future.
In addition to the pre-operative tests mentioned in the Participant Information Leaflet, participants consented to donating surplus samples of bypass graft vessel for scientific experiments in the laboratory.
Study Visits: Each study participant underwent a non-invasive, ultrasound assessment of endothelial function and thickness before heart surgery. A subgroup also underwent a non-invasive assessment of blood flow. Surplus segments of all harvested grafts were collected for laboratory studies.
The study aims to combine the pre-operative tests with laboratory measurements obtained from surgical samples during the time of the operation.
This information would then be used to investigate any predictive value of clinical outcome based on:
- Risk factors and medication at time of surgery
- Clinical outcome based on medical records
Study Recruitment: 231 patients undergoing coronary artery bypass graft surgery at the John Radcliffe Hospital, Oxford were successfully enrolled to the study. The study is no longer recruiting. Data collection continues through access to the patient’s medical records and extracting data from NHS Digital.
As this study is part of the Oxford Heart Vessels Fat (Ox-HVF) cohort, its results are interpreted together with the findings of other ox-HVF projects. Ox-HVF cohort is a cluster of clinical studies that provides synergistic results allowing the deployment of a multi-level strategy to understand the mechanisms of cardiovascular disease. This will add value to the research results and potentially allow the translation of the findings into clinical applications.
Patients may be contacted in the future for possible participation in future ethically approved studies.
Prof Charalambos Antoniades (CI), Prof Keith M Channon, Prof Paul Leeson, Prof David Taggart, n, Dr Colin Cunnington, Dr Rajesh Kharbanda, Mr Jonathan Diesch, Miss Laura Herdman
Research Funding: The study was funded by Oxford Health Services Research Committee (2004-2007) and received additional support from the British Heart Foundation, the Hellenic Cardiological Society, the European Society of Cardiology and the European Commission FP6 and FP7 programmes.
Study Approval: Ethical Approval was provided following review by the Division of Cardiovascular Medicine and the South Central Oxford Research Ethics Committee (Reference 04/Q1605/95). Document version 1.1 Oct 2016.
Announcements for the participants:
Announcement 25/5/2016: We are pleased to announce that since December 2015 the study chief investigator has changed (from Prof P Leeson to Prof C Antoniades). The new chief investigator can be contacted either directly by telephone (+441865228340) or by mail (West Wing level 6, John Radcliffe Hospital, Oxford University Hospital NHS Foundation Trust, Headley Way OX3 9DU, Oxford) or by using the online form found in this website.
Announcement 25/5/2016: In the original study documents and consent form (clause 3) we state that “I understand that the information gathered will be looked at by responsible individuals in the Department of Cardiovascular Medicine and Cardiothoracic Surgery or regulatory authorities where it is relevant to my taking part in research. I give permission for these individuals to access my records and to store them on a secure database linking my personal details, clinical notes and research findings”. This means that to keep your research records up to date throughout the duration of the study, we will send your NHS number and/or Date of Birth to the Oxford University Hospitals services and/or the NHS Digital who will link hospital admissions information to individual participants within the study. NHS Digital will then return your information to us with data about any health outcomes. NHS Digital will also link your NHS Number and/or Date of Birth to civil registration data from the Office for National Statistics (ONS) which provides information regarding mortality of participants over the time period of this research. All personal information exchanged between NHS Digital is protected and encrypted in line with strict regulations and codes of practice that ensure high security standards.