Asymptomatic carotid artery stenosis and cognitive outcomes after coronary artery bypass grafting

Abstract

Objective. Cognitive decline has a negative impact on early postoperative morbidity and affects subjective quality of life. The role of asymptomatic cerebrovascular disease in developing postoperative neurocognitive damage remains controversial. The aim of our study was to evaluate the impact of asymptomatic carotid artery stenosis on postoperative cognitive decline. Design. We investigated 127 patients undergoing coronary artery bypass grafting. The neuropsychological examination, including a cognitive battery of seven tests and two scales for evaluation of mood disorders, was conducted the day before surgery and before the discharge from hospital. Results. Early postoperative cognitive decline (POCD) was detected in 46% of patients. POCD was associated with longer duration of surgery (p = 0.02), low cardiac output syndrome perioperatively (p < 0.05), postoperative bleeding (p = 0.03), longer postoperative mechanical ventilation time and intensive care unit stay (p < 0.05). Carotid artery lesion was detected in 42 (68.8%) patients. Multivariate regression analysis showed that carotid artery stenosis of more than 50% was an independant predictor of POCD (OR 26.89, CI 6.44–112.34). Conclusions. Asymptomatic carotid artery stenosis is a risk factor for cognitive decline after coronary artery bypass grafting.