The Role of Fractional Flow Reserve in Coronary Artery Bypass Grafting
Research type
Research Study
Full title
Fractional Flow Reserve-Guided Versus Angiography-Guided Coronary Artery Bypass Grafting: A Randomised Controlled Trial
IRAS ID
268982
Contact name
Marjan Jahangiri
Contact email
Sponsor organisation
St George's Hospital, Foundation Trust
Duration of Study in the UK
3 years, 0 months, 4 days
Research summary
Surgical treatment of coronary artery disease is coronary artery bypass graft surgery (CABG). All blockages are bypassed to provide symptomatic relief and good post-operative outcomes. However, carrying out unrequired bypasses prolongs the operation time, and can potentially worsen outcomes. Accurate assessment of blocked coronary arteries is crucial.
The number of grafts varies depending on the blockages seen on pre-operative coronary angiography, whereby visual images of blood flow through the coronary arteries are generated. These are interpreted by the surgeon and a decision on which blockages necessitate grafting is made. Several studies have demonstrated that visual assessment can be subjective, and interpretation varies between doctors. This is particularly the case for moderate-severity blockages (40 – 70% blocked).
A novel technology, known as ‘fractional flow reserve’ (FFR), can be used as an adjunct alongside coronary angiography. A pressure-transducing wire is passed through the blockages and provides an accurate indicator of the reduction in blood flow to the heart muscle. If the drop in pressure is significant (>20-25% drop), then the blockage warrants intervention.
FFR has been extensively studied in patients who are undergoing ‘percutaneous coronary intervention’, where a short mesh tube (a ‘stent’) is inserted and keeps the artery open as a less-invasive alternative to surgery. The use of FFR in this procedure has been shown to provide superior outcomes compared to standard coronary angiography alone and its use is now widespread to guide stenting. However, less evidence exists for the role of FFR in CABG.
Our aims are to investigate the outcomes following CABG guided by coronary angiography compared to CABG guided by FFR measurements.
In this randomised controlled trial, patients undergoing CABG will be randomly allocated to either receive CABG where the number and site of the grafts will be guided by FFR measurements or by angiographic images alone.REC name
London - Queen Square Research Ethics Committee
REC reference
19/LO/1844
Date of REC Opinion
16 Jan 2020
REC opinion
Further Information Favourable Opinion