Background : Stroke can be a devastating complication after coronary artery bypass grafting (CABG). Silent cerebral infarction (SCI) is common in elderly patients, and – like previous cerebrovascular disease (CVD)– is a risk factor for stroke. We examined the ultrasonographic features of the carotid arteries as predictors of SCI in patients undergoing CABG.
Methods : Data for 633 CABG patients aged ≥ 60 yr were collected, and the patients were divided into three groups : control (n = 348), SCI (n = 175), and CVD (n = 110). We compared the images of carotid plaque, and the risk factors and incidence of stroke among the three groups, and calculated the probability of SCI.
Results : In the SCI group, the plaque score (PS) was 7.7 ± 4.7, the incidence of carotid stenosis (> 75%) was 13%, that of echolucent plaque was 37%, that of cerebral artery stenosis (> 50%) was 26%, and that of severe aortic atherosclerosis was 19%, being almost equal to the data for the CVD group. The incidence of stroke was 6.4% in the CVD group, 4.5% in the SCI group, and 1.4% in the control group (P < 0.05). Univariate analysis revealed that 5 factors were correlated with SCI : PS > 5.1, stenosis > 75%, echolucent plaque, peripheral artery disease (PAD), and creatinine ≥ 1.5 mg/dL. The probability of SCI in patients with all 5 risk factors was 0.77.
Conclusions : Ultrasonographic features combined with PAD and creatinine would be useful for prediction of SCI.
