On-Pump CABG Have Better Long Term Outcome than Off-Pump CABG

Proponents of off-pump CABG cite potentially lower rates of post–cardiopulmonary bypass complications, such as neurologic and kidney sequelae. Advocates of on-pump CABG raise concerns of potentially lower rates of completeness and effectiveness of revascularization as well as higher off-pump reintervention rates. To further investigate whether there may be long-term differences, Dr Jacquelyn A. Quin and her team conducted a study to evaluate the 10-year outcomes and costs of off-pump vs on-pump CABG in the Department of Veterans Affairs (VA) Randomized On/Off Bypass (ROOBY) trial.

Between February 2002 and May 2007, 2203 veterans in the ROOBY trial were randomly assigned to off-pump (n=1104) or on-pump (n=1099) CABG procedures at 18 participating VA medical centres. The researchers assessed the 10-year, post-CABG clinical outcomes and costs via centralized abstraction of electronic medical records combined with merges to VA and non-VA databases. The major outcome assessed was all-cause death and a composite endpoint identifying patients who had died or had undergone subsequent revascularization (ie, percutaneous coronary intervention [PCI] or repeated CABG). Secondary outcomes assessed were PCIs, repeated CABG procedures, changes in cardiac symptoms, and 2018-adjusted VA estimated costs. They used New York Heart Association functional class, Canadian Cardiovascular Society angina class, and atrial fibrillation to evaluate the changes from baseline to 10 years in post-CABG, clinically relevant cardiac symptoms.

Key findings of the study:

• Upon analysis, the researchers found that the 10-year death rates were 34.2% (n = 378) for the off-pump group and 31.1% (n = 342) for the on-pump group (relative risk, 1.05).
• They noted that the median time to the composite endpoint for the off-pump group (4.6 years) was approximately 4.3 months shorter than that for the on-pump group (5.0 years).
• They found no significant 10-year treatment-related differences for any other primary or secondary endpoints between the on-pump and the off-pump group.
• They also reconfirmed this in a sensitivity analysis after the removal of conversions.

The authors concluded, "No off-pump CABG advantages were found for 10-year death or revascularization endpoints; the time to composite endpoint was lower in the off-pump group than in the on-pump group. For veterans, in the absence of on-pump contraindications, a case cannot be made for supplanting the traditional on-pump CABG technique with an off-pump approach."

In an accompanying editorial, Dr Arnaldo Dimagli and his team wrote, "the 10-year results of the ROOBY trial support on-pump CABG as the default revascularization strategy, whereas off-pump CABG should be used selectively for patients who may gain benefit from it and, ideally, performed by surgeons experienced and skilled in its use."

For further information:

DOI: 10.1001/jamasurg.2021.7578