Introduction

Coronary artery bypass grafting (CABG) is the most frequently performed open cardiac surgical procedure, with approximately 300,000 operations recorded annually in the STS Adult Cardiac Surgery Database (ASCD).[1][2] Perioperative stroke is a dreaded complication of CABG and can lead to permanent disability and death. Perioperative stroke is a dreaded complication of CABG and can lead to permanent disability and death. The incidence of perioperative stroke after CABG is 1.3-1.6%, with an associated mortality rate of >16%.[3][4][5]

Perioperative stroke is defined as an intraoperative stroke or stroke occurring within 30 days postoperatively. The diagnostic criteria for clinical stroke varies, but contemporary studies include new-onset focal neurologic symptoms lasting >24 hours from a determined vascular origin or symptoms lasting < 24 hours with radiographic evidence of infarction in the corresponding territory.[6] Radiographic evidence of a brain infarct after CABG is substantially more common: a 2017 meta-analysis by Cho et al. demonstrated a 27% rate of radiographic stroke in 204 patients whose clinical stroke rate was 2.4%.[7] Coronary artery and cerebrovascular diseases share common risk factors and pathophysiology. Therefore, patients with coronary artery disease often exhibit some degree of carotid stenosis.[8]

Carotid artery stenosis is seen in up to 14% of patients with coronary artery disease undergoing CABG.[9][10][11] Carotid stenosis is a risk factor for perioperative stroke, but the proportion of perioperative strokes directly attributable to carotid stenosis remains unclear as atherosclerosis of the ascending aorta and aortic arch also confer stroke risk.[12] Furthermore, patients with concomitant coronary artery and carotid disease are often asymptomatic. Thus, surgical management of these patients remains controversial, with literature to support various treatment paradigms.