Significant MRFF grant awarded to support coronary bypass research project

Professor Alistair Royse, Department of Surgery, has been awarded $5 million from the Medical Research Future Fund (MRFF) to advance the TA Trial, a prospective randomised trial into the use of total arterial compared to non-arterial coronary surgery.

Project lead Alistair Royce in surgery. Project lead Professor Alistair Royse in surgery.

This grant is the first to be awarded by NHMRC or MRFF for a coronary bypass surgery project. It builds on an extensive body of work in Australia which culminated in a recent publication in the leading Journal of the American College of Cardiology , where more than 250,000 patients were matched and compared.

The TA Trial addresses a major gap in research and knowledge regarding the use of total arterial grafts in cardiac bypass surgery in patients with multiple co-morbidities. It is one of the largest fully funded cardiothoracic trials to proceed in Australia to date, and will aim to answer the question: is the exclusive use of arterial grafts during cardiac surgery bypass associated with superior perfect patency of grafts, and hence a reduction in direct and indirect cardiac, neurocognitive, cerebrovascular, and renal complications?

Coronary artery disease (CAD) is the leading single cause of disease burden (12.3%) and death (44,000 per year), affecting four million Australians annually. Patients presenting for treatment of CAD represent a cohort of patients with a high burden of co-existing cardiovascular co-morbidities and risk factors, who are at risk of complications post-CABG in multiple organ systems. Graft failure post-CABG occurs in approximately 12.9% of patients, affecting 2,193 Australians each year, and can lead directly to cardiac dysfunction, and indirectly to increased risk of cerebral and renal dysfunction, and/or death.

A major contributor to graft failure and the need for reintervention is the type of graft (arterial vs venous) used at surgery. Arterial grafts are associated with reduced atherosclerosis compared to venous grafts. The team found that arterial grafts rarely develop progressive atherosclerosis whereas most vein grafts do. By ten years, 40-50% of vein grafts have completely failed (occluded). Total arterial revascularisation (TAR) uses arterial grafts exclusively, and represents 5% of total CABG internationally, compared to the current standard of care which uses one or more venous grafts (non-TAR).

This multicentre RCT proposes that TAR (vs non-TAR) will be associated with superior perfect patency of grafts, and hence a reduction in direct and indirect cardiac, neurocognitive, cerebrovascular and renal complications.

Professor Royse, who has championed TAR for more than 20 years, and his multidisciplinary team will leverage their existing influential positions to advocate for TAR to become the standard of care for patients undergoing CABG, thus improving postoperative outcomes and survival of patients with cardiovascular disease.