Related Experiment Video
Updated: Mar 10, 2026
Single-Port Robotic-assisted Transaxillary Breast-conserving Surgery: A Prospective, Single-arm, Non-randomized Phase IIa Clinical Trial
Published on: August 19, 2025
Randomized Trial of Bilateral versus Single Internal-Thoracic-Artery Grafts
David P Taggart1, Douglas G Altman1, Alastair M Gray1
1From Nuffield Department of Surgical Sciences (D.P.T., B.L.), Centre for Statistics in Medicine, Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Sciences, Botnar Research Centre (D.G.A., S.G.), and the Health Economics Research Centre, Nuffield Department of Population Health (A.M.G.), University of Oxford, Oxford, the School of Clinical Sciences, University of Bristol and Bristol Royal Infirmary, Bristol (U.B.), and Norwich Medical School, University of East Anglia and Norfolk and Norwich University Hospital, Norwich (M.F.) - all in the United Kingdom.
Insights
Bilateral internal thoracic artery grafts in coronary-artery bypass grafting (CABG) showed no significant difference in 5-year mortality or cardiovascular events compared to single grafts. However, bilateral grafting increased sternal wound complications.
Area of Science:
- Cardiovascular Surgery
- Thoracic Surgery
- Grafting Techniques
Background:
- Coronary-artery bypass grafting (CABG) is a common procedure for treating coronary artery disease.
- The use of internal thoracic arteries (ITAs) as grafts is associated with superior long-term patency rates compared to vein grafts.
- Investigating the benefits of using bilateral internal thoracic arteries (BITAs) versus single internal thoracic artery (SITA) plus vein grafts is crucial for optimizing CABG outcomes.
Purpose of the Study:
- To compare the long-term efficacy and safety of bilateral internal thoracic artery (BITA) grafting versus single internal thoracic artery (SITA) grafting in patients undergoing coronary-artery bypass grafting (CABG).
- To evaluate the primary outcome of all-cause mortality at 10 years and secondary composite outcomes including myocardial infarction and stroke.
Main Methods:
- A randomized controlled trial involving 3102 patients undergoing CABG across 28 international cardiac surgical centers.
- Patients were assigned to either SITA grafting or BITA grafting.
- Primary outcome: all-cause mortality at 10 years. Secondary outcome: composite of death, myocardial infarction, or stroke. Interim analysis at 5 years.
Main Results:
- At 5-year follow-up, no significant difference in all-cause mortality (8.7% BITA vs. 8.4% SITA; P=0.77) or the composite outcome of death, myocardial infarction, or stroke (12.2% BITA vs. 12.7% SITA; P=0.69) was observed.
- Sternal wound complications were significantly higher in the BITA group (3.5%) compared to the SITA group (1.9%; P=0.005).
- Sternal reconstruction rates were also higher in the BITA group (1.9% vs. 0.6%; P=0.002).
Conclusions:
- Bilateral internal thoracic artery grafting does not offer significant advantages over single internal thoracic artery grafting in terms of mortality or major cardiovascular events at 5 years post-CABG.
- The use of bilateral internal thoracic arteries is associated with an increased risk of sternal wound complications and sternal reconstruction.
- Long-term 10-year follow-up data is still pending to fully ascertain the long-term benefits or risks of BITA grafting.
Background:
The use of bilateral internal thoracic (mammary) arteries for coronary-artery bypass grafting (CABG) may improve long-term outcomes as compared with the use of a single internal-thoracic-artery plus vein grafts.
Methods:
We randomly assigned patients scheduled for CABG to undergo single or bilateral internal-thoracic-artery grafting in 28 cardiac surgical centers in seven countries. The primary outcome was death from any cause at 10 years. The composite of death from any cause, myocardial infarction, or stroke was a secondary outcome. Interim analyses were prespecified at 5 years of follow-up.
Results:
A total of 3102 patients were enrolled; 1554 were randomly assigned to undergo single internal-thoracic-artery grafting (the single-graft group) and 1548 to undergo bilateral internal-thoracic-artery grafting (the bilateral-graft group). At 5 years of follow-up, the rate of death was 8.7% in the bilateral-graft group and 8.4% in the single-graft group (hazard ratio, 1.04; 95% confidence interval [CI], 0.81 to 1.32; P=0.77), and the rate of the composite of death from any cause, myocardial infarction, or stroke was 12.2% and 12.7%, respectively (hazard ratio, 0.96; 95% CI, 0.79 to 1.17; P=0.69). The rate of sternal wound complication was 3.5% in the bilateral-graft group versus 1.9% in the single-graft group (P=0.005), and the rate of sternal reconstruction was 1.9% versus 0.6% (P=0.002).
Conclusions:
Among patients undergoing CABG, there was no significant difference between those receiving single internal-thoracic-artery grafts and those receiving bilateral internal-thoracic-artery grafts with regard to mortality or the rates of cardiovascular events at 5 years of follow-up. There were more sternal wound complications with bilateral internal-thoracic-artery grafting than with single internal-thoracic-artery grafting. Ten-year follow-up is ongoing. (Funded by the British Heart Foundation and others; ART Current Controlled Trials number, ISRCTN46552265 .).
