The goal of this study is to establish a prospective study to focus on the high-risk stroke population who require coronary artery bypass graft surgery. It will divide the eligible patients into 1:1 group by simple randomization method. The control group adopt the traditional diagnosis and treatment mode, and only head CT plain scan and carotid artery ultrasound shall be performed. If necessary, relevant disciplines would be consulted but no integrated assessment of cervicocerebral vessels be arranged. The final treatment plan would be decided by the surgeon alone. The experimental group adopt the multidisciplinary collaboration and integrated evaluation mode. In addition to routine diagnosis and treatment as above-mentioned, integrated assessment of cervicocerebral vessels shall be performed, including transcranial color-coded doppler, cerebral perfusion with multislice CT, and cognitive function assessment. Based on the above results, surgical plans will be formulated jointly by multiple disciplines including neurologists, vascular surgeons, ICU physicians and cardiac surgeons. Researchers will compare the two groups to investigate whether integrated assessment of cervicocerebral vessels can reduce the incidence of brain injury compared with conventional diagnosis and treatment mode.