Screening carotid artery duplex in patients undergoing cardiac surgery

We sought to determine the prevalence of carotid artery stenosis (CAS)>50% in a large, multi-institutional health maintenance organization found during duplex ultrasonography screening before cardiac surgery and to identify risk factors to increase the yield of a preoperative screening program.

This retrospective review study was conducted on 722 patients who had undergone duplex ultrasonography screening of the carotid artery before cardiac surgery between June 2008 and February 2011. The primary outcome was CAS>50% detected on duplex ultrasonography screening.

Seven hundred twenty-two patients (66.2% men; median age: 71 years) underwent duplex ultrasonography screening of the carotid artery before cardiac surgery. The main indications for cardiac surgery were valvular disease (39.5%) and coronary artery disease (36.3%). One hundred eighteen patients (16.3%) had CAS≥50%. Among the patients found to have carotid stenosis, 38 patients (32.2%) had bilateral stenosis>50% and 37 patients (31.4%) had at least 70% unilateral stenosis. The presence of peripheral vascular disease (odds ratio [OR]: 2.93 [95% confidence interval {CI}: 1.87-4.60]; P<0.001), and history of cerebrovascular disease within 12 months (OR: 4.57 [95% CI: 1.18-17.77]; P=0.028) were risk factors associated with CAS. Patients who have coronary artery disease with cardiac catheterization showing left main disease (OR: 6.80 [95% CI: 3.02-15.29]; P<0.001), 3-vessel disease or more (OR: 2.78 [95% CI: 1.43-5.43]; P=0.003), or both (OR: 4.13 [95% CI: 1.89-9.06]; P<0.001) were found to be significantly more likely to have CAS>50%.

Independent risk factors that are predictive of the presence of CAS are peripheral vascular disease, having had a previous cerebrovascular accident, and coronary artery disease with left main or 3-vessel disease. Routine carotid duplex ultrasonography scanning may not be necessary for all patients undergoing cardiac surgery, and selective carotid screening programs may be considered in patients with symptomatic atherosclerosis disease or advanced coronary artery disease.