Patients who present with acute ischemic stroke, carotid bruit or significant coronary artery disease benefit from evaluation of cerebrovascular disease including carotid artery stenosis. Recently, this assessment has become increasingly vital since selected asymptomatic individuals with internal carotid artery stenosis greater than 70% can benefit from carotid endarterectomy1. Cerebrovascular ultrasound or Carotid Duplex Ultrasonography (CDUS) is often used in patients with planned Coronary Artery Bypass Grafting (CABG), known atherosclerosis (coronary or peripheral artery disease), and syncope. Although studies2, 3 have shown correlation of carotid artery disease and coronary artery disease, its utility in asymptomatic patients is unclear4. This study aimed to evaluate the effective use of CDUS to diagnose significant cerebrovascular disease (CBVD) in this group of patients.
After institutional IRB approval, we included 827 carotid ultrasounds consecutively ordered between March 1st, 2013 and August 31st, 2013 at Newark Beth Israel Medical Center. Demographic characteristics such as age, sex and clinical variables such as diabetes mellitus, systemic hypertension, coronary artery disease (CAD), peripheral artery disease (PAD), smoking status, carotid bruit and indications were formulated. This was a retrospective analysis and all investigators were blinded about the final report while performing chart review.
In addition to visualization of carotid arteries, vertebral and subclavian arteries were also examined. Stenosis in subclavian arteries, vertebral, basilar arteries or greater than 60% reduction in diameter of internal carotid artery (ICA) was considered significant cerebroavascular disease (CBVD). All carotid ultrasounds were performed in accordance with Intersocietal Commission for Accreditation of Vascular Laboratories (ICAVL) guidelines. Moreover, plaque characteristics were also identified in 79 of the available 88 carotid ultrasounds with CBVD. All results were read and confirmed by vascular surgeons.
Statistical analysis was completed using SPSS software version 22.0. Descriptive data such as age and sex were tabulated using frequency, median and interquartile range (IQR). Multivariate logistic regression analysis, odds ratio and 95% confidence intervals were calculated to determine association of various risk factors with CBVD.
Baseline characteristics and demographics are shown in Table I. Median age of participants was 69 (IQR 65-78) in patients with CBVD and 67 (IQR 55-76) in individuals with no CBVD. CDUS was positive in only 88 (10.6%) out of 827 cases and considering this was over a period of only 6 months makes it even more astounding. This includes 85 cases with greater than 60% occlusion in carotid arteries and 3 patients with isolated vertebral or subclavian artery occlusion. In addition, the yield of carotid ultrasound was different among various indications (Table I and Figure I). Patients...