Preoperative extracranial carotid artery examination with ultrasonography in patients undergoing coronary artery bypass grafting in Japan

We investigated the incidence, degree, and plaque characteristics of extracranial carotid stenosis with carotid ultrasonography (CUS) in patients undergoing coronary artery bypass grafting (CABG). Preoperative CUS was performed on 221 patients (442 carotid arteries) undergoing CABG. The degree of extracranial carotid stenosis was calculated based on the area stenosis, and it was classified into six grades as follows: grade (G) 0, G1 (1%-29%), G2 (30%-49%), G3 (50%-69%), G4 (70%-99%), and G5 (occlusion). The incidence of G4 was 4.1% and G5 1.6%. There were 48 arteries rated G3 or G4. Hypoechoic plaque was detected in 28 of the 48 arteries (58%), and heterogeneous plaque was detected in 37 arteries (73%). Ulcerative plaque was detected in 27 arteries (56%); when comparing the G3 and G4 groups, ulcerative plaque was found more frequently in G4 than in G3 (14/18 vs 13/30 arteries, P < 0.02). Our study demonstrated that patients undergoing CABG with extracranial severe carotid stenosis tend to have heterogeneous, hypoechoic, and ulcerative plaque. We believe that preoperative CUS should be used to evaluate the plaque characteristics of extracranial carotid stenosis.