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Updated: Jan 21, 2026

Surgical Swine Model of Chronic Cardiac Ischemia Treated by Off-Pump Coronary Artery Bypass Graft Surgery
Published on: March 27, 2018
Off-Pump Versus On-Pump Bypass Surgery for Left Main Coronary Artery Disease
Umberto Benedetto1, John Puskas2, Arie Pieter Kappetein3
1University of Bristol, Bristol, United Kingdom.
Background:
Concerns remain for a greater risk of incomplete revascularization and reduced survival with off-pump coronary artery bypass grafting (CABG) surgery compared with on-pump surgery particularly in patients with left main disease and extensive underlying myocardial ischemia.
Objectives:
This study sought to compare outcomes following off-pump versus on-pump surgery for left main disease by performing a post hoc analysis from the multicenter, randomized EXCEL (Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) trial.
Methods:
The EXCEL trial was designed to compare percutaneous coronary intervention with everolimus-eluting stents versus CABG in patients with left main disease. CABG was performed with or without cardiopulmonary bypass (on-pump vs. off-pump surgery) according to the discretion of the operator. The 3-year outcomes in the off-pump and on-pump groups were compared using inverse probability of treatment weighting (IPTW) for treatment effect estimation.
Results:
Among 923 CABG patients, 652 and 271 patients underwent on-pump and off-pump surgery, respectively. Despite a similar extent of disease, off-pump surgery was associated with a lower rate of revascularization of the left circumflex coronary artery (84.1% vs. 90.0%; p = 0.01) and right coronary artery (31.1% vs. 40.6%; p = 0.007). After IPTW adjustment for baseline differences, off-pump surgery was associated with a significantly increased risk of 3-year all-cause death (8.8% vs. 4.5%; hazard ratio: 1.94; 95% confidence interval: 1.10 to 3.41; p = 0.02) and a nonsignificant difference in the risk for the composite endpoint of death, myocardial infarction, or stroke (11.8% vs. 9.2%; hazard ratio: 1.28; 95% confidence interval: 0.82 to 2.00; p = 0.28).
Conclusions:
Among patients with left main disease treated with CABG in the EXCEL trial, off-pump surgery was associated with a lower rate of revascularization of the coronary arteries supplying the inferolateral wall and an increased risk of 3-year all-cause death compared with on-pump surgery.
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