Best Bypass Surgery—Cognitive Study - BBS—Cognitive Study


The goal of the trial was to evaluate cognitive outcomes in elderly high-risk patients after off-pump compared with conventional coronary artery bypass grafting (CABG) surgery.


Degree and frequency of postoperative stroke and cognitive dysfunction will be lower after off-pump CABG (OPCAB) compared with conventional CABG (CCAB).

Study Design

Study Design:

Patients Enrolled: 120
Mean Follow Up: 3 months postoperatively
Mean Patient Age: Mean age 76 years
Female: 40
Mean Ejection Fraction: Mean baseline ejection fraction 49%

Patient Populations:

Known ischemic three-vessel disease affecting one of the marginal coronary arteries, scheduled for elective or subacute CABG, age ≥55 years, and who had a EuroSCORE ≥5


Previous heart surgery, ejection fraction <30%, unstable preoperative condition, or unable to give informed consent

Drug/Procedures Used:

Patients were randomized to CCAB or OPCAB surgery. The cohort of elderly patients who met the substudy inclusion criteria and were enrolled included 61 OPCAB patients and 59 CCAB patients. Neuropsychological tests were performed at baseline and follow-up.

Principal Findings:

Baseline characteristics were similar between the treatment groups, with a mean age of 76 years and a mean EuroSCORE of 6.68. There was no difference in the length of the operation time (159 minutes for OPCAB and 152 minutes for CCAB). Mean cardiopulmonary bypass time was 60 minutes in the CCAB group. Four patients in the OPCAB group actually received CCAB, and one patient in the CCAB group received OPCAB.

There was no difference in cognitive dysfunction, defined as ≥2 of the 7 possible deficits, between treatment groups (7.4% for OPCAB vs. 9.8% for CCAB, p = 0.7). A cognitive decline of 20% or greater in scores at 3 months compared with baseline also occurred at a similar frequency between groups (20.4% for OPCAB vs. 23.5% for CCAB, p = 0.8).


Among elderly high-risk patients undergoing CABG surgery, there was no difference in cognitive outcomes at 3 months associated with OPCAB compared with CCAB.

Prior studies have evaluated cognitive outcomes between OPCAB and CCAB with varied results, but many of these trials were conducted in lower risk, often younger patients. The present study is one of the first randomized studies to focus on elderly patients, whom are thought to be at the highest risk for cognitive impairment. It is unknown if similar results would be shown with longer follow-up.


Jensen BO, Hughes P, Rasmussen LS, Pedersen PU, Steinbruchel DA. Cognitive outcomes in elderly high-risk patients after off-pump versus conventional coronary artery bypass grafting: a randomized trial. Circulation 2006;113:2790-5.

Clinical Topics: Cardiac Surgery, Invasive Cardiovascular Angiography and Intervention

Keywords: Cognition, Stroke, Follow-Up Studies, Neuropsychological Tests, Coronary Artery Bypass, Off-Pump, Cardiopulmonary Bypass, Coronary Artery Bypass

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