Analysis of Carotid Ultrasound Findings on Cardiovascular Events in Patients with Coronary Artery Disease during Seven-Year Follow-Up

BACKGROUND AND OBJECTIVES Both carotid intima-media thickness (CIMT) and carotid plaque are important factors in the primary prevention of cardiac disease. However, it is unclear which one is more important for prognosis, especially in patients with coronary artery disease (CAD). SUBJECTS AND METHODS In total, 1426 consecutive CAD patients, proven by angiography, were followed-up for a mean of 85 months. The study population was divided into four groups depending on the CIMT (≥0.83 mm, >95 percentile in Korea) and the presence or absence of carotid plaque. RESULTS Patients with carotid plaque and thick CIMT (n=237, 16.6%) had a higher prevalence of hypertension, diabetes mellitus, and dyslipidemia than those had plaque and thin CIMT (n=213, 14.9%), those without plaque and thick CIMT (n=265, 18.6%) and those without plaque and thin CIMT (n=711, 49.9%). The patients with carotid plaque and thick CIMT group had a higher cardiac mortality rate (20.7% vs. 13.1%, 9.4% and 3.9%, respectively, p<0.001) and higher major adverse cardiovascular events (MACE) including death, acute myocardial infarction, and stroke (27.8% vs. 18.8%, 15.5% and 9.3%, respectively, p<0.001) than any other groups. Multivariate Cox regression analysis showed that the presence of carotid plaque with thick CIMT had the highest hazard ratio (HR) compared to other groups (HR 2.23 vs. 1.81, 2.01) for cardiac mortality. Also, carotid plaque had a higher HR than CIMT for mortality (HR 1.56 vs. 1.37) and MACE (HR 1.54 vs. 1.36) in the total study population. CONCLUSION Carotid plaque is a more important prognostic factor than CIMT in patients with CAD, and adding a thick CIMT to carotid plaque increases the prognostic power for cardiac events.