Cognitive outcomes five years after not undergoing coronary artery bypass graft surgery.

BACKGROUND: Patients with coronary artery disease who underwent coronary artery bypass graft surgery have a high risk of cognitive decline 5 years after the procedure. It is conceivable that this is not caused by the operation, but by natural aging. METHODS: Psychologists repeatedly administered a battery of seven neuropsychological tests with eight main variables to 112 subjects without known coronary artery disease, with a time interval of 5 years. Cognitive decline was defined as deterioration in performance beyond normal variation in at least two of the eight main variables. The incidence of cognitive decline in the control subjects was compared with the incidence of cognitive decline in the 281 participants of the Octopus Study, who underwent coronary artery bypass graft surgery 5 years earlier. Patients and control subjects were age-matched. RESULTS: After 5 years, cognitive outcome could be determined in 99 of 112 control subjects (88%) and 240 of 281 coronary artery bypass graft surgery patients (85%). Cognitive decline was present in 82 (34.2%) of 240 coronary artery bypass graft surgery patients and in 16 (16.2%) of 99 control subjects (crude odds ratio, 2.69; 95% confidence interval, 1.48 to 4.90). However, after correction for differences in age, sex, education, and baseline comorbidity between the patients and the control subjects, the odds ratio was 1.37 (95% confidence interval, 0.65 to 2.92). CONCLUSIONS: We were unable to demonstrate that patients who underwent coronary artery bypass graft surgery have more cognitive decline after 5 years than control subjects without coronary artery disease.

Beating heart versus conventional cardiopulmonary bypass: the octopus experience: a randomized comparison of 281 patients undergoing coronary artery bypass surgery with or without cardiopulmonary bypass.

In the Octopus Study, 281 coronary artery bypass surgery patients were randomized to surgery with or without cardiopulmonary bypass. The primary objective was to compare cognitive outcome between off-pump and on-pump coronary artery bypass surgery. Before and after surgery, psychologists administered a battery of 10 neuropsychological tests to the patients. Cognitive decline was defined as a decrease in an individual's performance of at least 20% from baseline, in at least 20% of the main variables. According to this definition, cognitive decline was present in 21% in the off-pump group and 29% in the on-pump group, 3 months after the procedure (P = .15). At 12 months, cognitive decline was present in 31% in the off-pump group and 34% in the on-pump group (P = .69). These results indicated that patients undergoing coronary artery bypass surgery without cardiopulmonary bypass had improved cognitive outcomes 3 months after the procedure, but the effects were limited and became negligible at 12 months. The same definition of cognitive decline was also applied to 112 volunteers not undergoing surgery. The definition labeled 28% of the control subjects as suffering from cognitive decline, 3 months after their first assessment. This suggests that the natural fluctuations in performance during repeated neuropsychological testing should be included in the statistical analysis of cognitive decline. Using an alternative definition of cognitive decline that takes these natural fluctuations in performance into account, the proportions of coronary artery bypass surgery patients displaying cognitive decline were substantially lower. This indicates that the incidence of cognitive decline after coronary artery bypass surgery has been overestimated.

Cognitive self-assessment one year after on-pump and off-pump coronary artery bypass grafting.

BACKGROUND: Coronary artery bypass grafting (CABG) is associated with significant cerebral morbidity. This is usually manifested as cognitive decline and may be caused by cardiopulmonary bypass. The primary objective of this study was to explore whether patients report more cognitive failures 1 year after CABG than preoperatively. Secondary objectives were to evaluate whether there is a difference in reported cognitive failures between patients undergoing on-pump and off-pump CABG and whether a difference between CABG patients and healthy control subjects exists. Finally the relation between objective and subjective cognitive functioning was quantified. METHODS: In this prospective study, the Cognitive Failures Questionnaire (CFQ) was assigned preoperatively and 1 year postoperatively to 81 patients who were randomly assigned to undergo off-pump (n = 45) or on-pump (n = 36) CABG. A control sample of 112 age-matched healthy subjects was included who were administered the CFQ once. RESULTS: No difference was found in the total CFQ score (p = 0.222) and CFQ worry score (p = 0.207) between 1 year after CABG and before CABG. There was no difference between on-pump and off-pump CABG (total score, p = 0.458; worry score, p = 0.563). A significant difference was found in CFQ total score between CABG patients and control subjects (p < 0.001), with control subjects reporting more cognitive failures than CABG patients. Finally, patients who showed cognitive decline in the Octopus trial did not have a higher CFQ total score (p = 0.671) and CFQ worry score (p = 0.772) than patients without cognitive decline 1 year after CABG. CONCLUSIONS: The present findings suggest that CABG does not result in a substantial proportion of patients with subjectively experienced cognitive decline 1 year after the procedure, irrespective of the type of surgical technique (on-pump versus off-pump).

Cognitive outcome after off-pump and on-pump coronary artery bypass graft surgery: a randomized trial.

CONTEXT: Coronary artery bypass graft (CABG) surgery is associated with a decline in cognitive function, which has largely been attributed to the use of cardiopulmonary bypass (on-pump procedures). Cardiac stabilizers facilitate CABG surgery without use of cardiopulmonary bypass (off-pump procedures) and should reduce the cognitive decline associated with on-pump procedures. OBJECTIVE: To compare the effect of CABG surgery with (on-pump) and without (off-pump) cardiopulmonary bypass on cognitive outcome. DESIGN AND SETTING: Randomized controlled trial conducted in the Netherlands of CABG surgery patients enrolled from March 1998 through August 2000, with 3- and 12-month follow-up. PARTICIPANTS AND INTERVENTION: Patients scheduled for their first CABG surgery (mean age, 61 years; n = 281) were randomly assigned to off-pump surgery (n = 142) or on-pump surgery (n = 139). MAIN OUTCOME MEASURES: Cognitive outcome at 3 and 12 months, which was determined by psychologists (blinded for randomization) who administered 10 neuropsychological tests before and after surgery. Quality of life, stroke rate, and all-cause mortality at 3 and 12 months were secondary outcome measures. RESULTS: Cognitive outcome could be determined at 3 months in 248 patients. Cognitive decline occurred in 21% in the off-pump group and 29% in the on-pump group (relative risk [RR], 0.65; 95% confidence interval [CI], 0.36-1.16; P =.15). The overall standardized change score (ie, improvement of cognitive performance) was 0.19 in the off-pump vs 0.13 in the on-pump group (P =.03). At 12 months, cognitive decline occurred in 30.8% in the off-pump group and 33.6% in the on-pump group (RR, 0.88; 95% CI, 0.52-1.49; P =.69). The overall standardized change score was 0.19 in the off-pump vs 0.12 in the on-pump group (P =.09). No statistically significant differences were observed between the on-pump and off-pump groups in quality of life, stroke rate, or all-cause mortality at 3 and 12 months. CONCLUSION: Patients who received their first CABG surgery without cardiopulmonary bypass had improved cognitive outcomes 3 months after the procedure, but the effects were limited and became negligible at 12 months.