Aortic atheroma burden and cognitive dysfunction after coronary artery bypass graft surgery

Neurocognitive dysfunction (NCD) after coronary artery bypass graft (CABG) surgery is a common problem. Atherosclerotic disease of the aorta is a known risk factor for stroke after cardiac surgery, but its relationship to NCD is unclear. This study investigates the relationship between aortic atherosclerotic disease and NCD after CABG.

Patients undergoing primary elective CABG were enrolled in an ongoing investigation of NCD after CABG. Intraoperative transesophageal echocardiography (TEE) of the thoracic aorta was performed and analyzed off-line to quantify atheroma burden. Neurocognitive evaluation was performed, both preoperatively and at 6 weeks after surgery. Multivariable linear regression (controlling for age, years of education, and base line cognitive index) was used to determine the relationship between NCD and atheroma burden in the ascending, arch, and descending aorta.

One hundred sixty-two patients who had a complete neurocognitive evaluation and adequate TEE images were studied. No significant relationship was found between NCD and atheroma burden in the ascending (p = 0.22), arch (p = 0.89) or descending aorta (p = 0.64).

Although the etiology of NCD is likely multifactorial, our results suggest that aortic atherosclerosis may not be the primary factor in the pathogenesis of post-CABG cognitive changes.