The expected outcome of better and improved patency of bypass grafts and its direct relation to pre-operative iFR measurements of stenosis as compared to direct visual physiology of stenosis in the coronary angiogram.

To establish the correlation between the use of intracoronary physiology and improved graft patency at 12 months for patients undergoing CABG surgery.

It is a minimum of 28 and a maximum of 100 patients single-centre proof or concept/ observational study/ pilot study.

Patients suffering from coronary artery disease undergo coronary artery bypass grafting surgery (CABG) as the standard of care. The selection of which vessels to bypass is usually at the discretion of the surgeon forming an opinion based on the pre-operative angiographic imaging. Intra-coronary physiology (iFR measurements) is more accurate to determine the level of damage to the coronary arteries; however, currently it is not used for CABG pre-assessment, but only for percutaneous intervention also known as stenting as it has been shown to improve outcomes. Although, the use of intracoronary physiology has not been extensively studied or validated in patients undergoing CABG.

Patients with multi-vessel coronary artery disease (CAD) who are planned for surgical revascularization with coronary artery bypass grafting (CABG), will have iFR measurement taken during invasive coronary angiography as part of standard care, they will undergo CABG and will have echocardiography at 3 months and computed tomography coronary angiography (CTCA) at 12 months.

Early graft failure will be assessed by the presentation of any clinical symptoms, major adverse cardiovascular and cerebrovascular events (MACCE) and echocardiography at 3 months. The endpoint will be graft patency as assessed by CT coronary angiography at 12 months.

Anticipated recruitment is 12-24 months. Follow-up with echocardiography at 3 months and a CTCA at 12 months. Quality of Life questionnaire will be completed by the patient at 3 and 12 months during the follow-up appointment.

Patients will continue on optimal medical therapy. Clinic visit and quality of life scale questionnaires will be recorded at 3 and 12 months and echocardiography will be assessed at 3 months. Graft patency at 12 months will be assessed with a CT coronary angiography.

INCLUSION CRITERIA

1. Age of 25 to 80 years of age
2. Willing to participate and able to understand, read and sign the informed consent form (ICF) before standard of care elective CABG surgery
3. Undergoing isolated first-time elective CABG surgery
4. Available pre-operative angiography data with iFR measurements done during the pre-operative angiography

EXCLUSION CRITERIA

1. Emergency CABG surgery
2. Ejection Fraction≤ 40%
3. Severe valvular heart disease

Retrospective cohort study - approximately 250 pts Prospective cohort study - minimum 28 pts - maximum 100 pts

Anonymised individual participant data for all primary and secondary outcome measures will be made available.

36 months

According to study protocol