Changes in Cerebral Blood Flow and Cognitive Function in Patients Undergoing Coronary Bypass Surgery With Cardiopulmonary Bypass

Purpose: to study effect of coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB) on regional cerebral blood flow and cognitive function in patients with ischemic heart disease (IHD). Material and methods. We included into this study 22 patients with IHD subjected to CABG surgery with CPB. All patients underwent brain SPECT scanning and comprehensive neuropsychological testing 1 day before, 10-14 days and 6 months after surgery. Results. Overall CABG with CPB was followed by reduction of regional cerebral blood flow relative to baseline in frontal and parietal cortex (p < 0.01). Substantial reduction (>5%) of cerebral perfusion in early postoperative period was observed in 15 patients (68%) while seven patients (32%) had no significant changes of regional cerebral blood flow. Changes of cerebral perfusion correlated with dynamics of cognitive status. Mean measures of immediate verbal memory, delayed memory, and learning decreased after surgery by 25.6 (p=0.002), 43.3 (p=0.000003), and 23.1% (p=0.00000), respectively. Moreover after CABG with CPB patients demonstrated slowing of psychomotor speed by 13.6% (p=0.03). Conclusion. CABG with CPB was associated with reduction of cerebral perfusion leading to cognitive dysfunction. Immediate and delayed verbal and visual memory, learning and psychomotor speed were most sensitive to the negative effects of surgery.