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Updated: Aug 17, 2026
Human Internal Mammary Artery (IMA) Transplantation and Stenting: A Human Model to Study the Development of In-Stent Restenosis
Published on: May 9, 2012
Early and long-term outcomes of bilateral internal mammary artery versus radial artery grafting: A national cohort
Juan A Montero1,2, Santiago Cubas1,2, Maximiliano Hernandez2
1Cardiac Surgery Department, Hospital de Clínicas, Centro Cardiovascular Universitario, Montevideo, Uruguay.
Insights
Bilateral internal mammary artery (BIMA) grafting showed better early outcomes but no consistent long-term survival advantage over left internal mammary artery (LIMA) plus radial artery (RA) grafting in coronary artery bypass grafting (CABG). Individualized approaches are suggested.
Area of Science:
- Cardiovascular Surgery
- Thoracic Surgery
- Cardiac Surgery Outcomes
Background:
- Coronary artery bypass grafting (CABG) is a common treatment for coronary artery disease.
- Multi-arterial grafting strategies aim to improve CABG outcomes.
- The comparative efficacy of bilateral internal mammary artery (BIMA) versus left internal mammary artery (LIMA) plus radial artery (RA) grafting requires further investigation.
Purpose of the Study:
- To compare early and long-term outcomes of BIMA versus LIMA+RA grafting in isolated CABG.
- To evaluate survival, ischemic events, and complications associated with these grafting strategies.
Main Methods:
- Retrospective national cohort study (2002-2022) of isolated CABG patients.
- Propensity score matching with multiple imputation for group comparison.
- Kaplan-Meier, Cox models, and restricted mean survival time (RMST) for survival analysis.
- Competing-risk regression for repeat revascularization assessment.
Main Results:
- BIMA grafting was associated with lower operative mortality and improved early outcomes.
- No significant difference in 10-year RMST between BIMA and LIMA+RA groups.
- BIMA grafting did not consistently demonstrate improved long-term survival in sensitivity analyses.
- No differences in major ischemic events, deep sternal wound infection, or repeat revascularization.
Conclusions:
- BIMA grafting offers early benefits but lacks consistent long-term survival advantage over LIMA+RA grafting in isolated CABG.
- Sensitivity analyses did not support a consistent survival benefit for BIMA.
- An individualized approach to graft selection is recommended based on patient factors.
Objective:
To compare early and long-term outcomes of bilateral internal mammary artery (BIMA) grafting versus left internal mammary artery (LIMA) plus radial artery (RA) grafting in patients undergoing isolated coronary artery bypass grafting (CABG).
Methods:
This retrospective national cohort study included patients undergoing isolated CABG with multiarterial grafting in Uruguay between 2002 and 2022. Patients undergoing BIMA grafting or LIMA+RA grafting were identified from a mandatory national cardiac surgery database. Propensity score matching with multiple imputation was used to balance baseline characteristics between the 2 groups. Long-term survival was assessed using Kaplan-Meier analysis, Cox proportional hazards models, and restricted mean survival time (RMST). Competing-risk regression (Fine-Gray) was used to evaluate repeat percutaneous coronary intervention. Effect modification by sex and diabetes was explored.
Results:
Among 2882 patients (2132 BIMA and 750 LIMA+RA), 4203 matched (with replacement) patients were analyzed. At 10 years, RMST did not differ between groups (9.06 years for BIMA vs 8.98 years for LIMA+RA; P = .36), and BIMA grafting was associated with improved long-term survival (hazard ratio, 0.73; 95% confidence interval, 0.55-0.93; P = .03) which was not supported by sensitivity analyses. There was no interaction with sex or with diabetes. BIMA grafting was associated with lower operative mortality but with a higher rate of mechanical ventilation and longer duration of inotrope use. No between-group differences were observed in major ischemic events, deep sternal wound infection, or repeat revascularization.
Conclusions:
In this national cohort, BIMA grafting improved early outcomes but did not confer a consistent overall long-term survival advantage compared with LIMA+RA grafting. A lack of support from sensitivity analyses implies the need for an individualized approach.
