The desire to avoid the perceived ill effects of coronary artery bypass graft (CABG) surgery with the use of cardiopulmonary bypass (on-pump CABG) has led to a renewed interest in bypass surgery on the beating heart (off-pump CABG). The off-pump procedure, however, is technically more demanding, and it is unknown whether off-pump surgery can match the long-term cardiac benefits of on-pump surgery or improve cognitive outcomes.

Diederik van Dijk, M.D., Ph.D., of the University Medical Center Utrecht, the Netherlands and colleagues assessed the five year cognitive and cardiac outcomes of 281 patients who were randomized to off-pump (n = 142) or on-pump (n = 139) CABG surgery. After 5 years, 130 patients were alive in each group.

Cognitive outcomes could be determined in 123 and 117 patients in the off-pump and on-pump groups, respectively. When applying the standard definition of cognitive decline (20 percent decline in 20 percent of the main test variables), 62 (50.4 percent) of 123 patients in the off-pump group and 59 (50.4 percent) of 117 patients in the on-pump group had cognitive decline.

Thirty patients assigned to undergo off-pump surgery (21.1 percent) and 25 patients assigned to undergo on-pump surgery (18.0 percent) had experienced a cardiovascular event. There were no differences between the 2 groups in the overall measure of quality of life or in angina status.

"We conclude that in low-risk patients undergoing CABG surgery, avoiding the use of cardiopulmonary bypass had no effect on cognitive or cardiac outcome 5 years after the procedure," the authors of the study conclude. "The present results suggest that factors other than cardiopulmonary bypass may be responsible for cognitive decline, such as anaesthesia and the generalized inflammatory response that is associated with major surgical procedures."; Source: American Medical Association