Use of carotid plaque neovascularization at contrast-enhanced US to predict coronary events in patients with coronary artery disease.

Abstract

To determine whether carotid plaque neovascularization as assessed with contrast-enhanced ultrasonography (US) can help predict future coronary events in patients with stable coronary artery disease (CAD). The study was approved by the hospital ethics committee, and informed consent was obtained from all patients. Three hundred twelve consecutive patients (228 men; mean age, 63 years ± 9; age range, 42-88 years) with both CAD and at least one carotid plaque thicker than 2.0 mm underwent both standard and contrast-enhanced carotid US. Patients with stable CAD were followed up for 8-47 months (mean, 33 months ± 9) or until a coronary event occurred. Statistical analysis was performed with the Student t test, χ(2) analysis, Kaplan-Meier method, and Cox proportional hazards regression models. Contrast material enhancement of plaque was seen in 42 of 51 patients (82%) with acute coronary syndrome (ACS) and 114 of 261 patients (43.7%) with stable CAD (P < .001). Coronary events occurred during the follow-up period in 24 of 111 patients (21.6%) with contrast material enhancement of plaque and only seven of 137 patients (5.1%) without enhancement (P< .001). In 248 patients with stable CAD and follow-up, Kaplan-Meier analysis demonstrated a significantly higher probability of developing coronary events in patients with contrast material enhancement of plaque than in those without contrast material enhancement (P < .001). The presence of contrast material enhancement of plaque was a significant and independent predictor of future coronary events in patients with stable CAD (odds ratio: 3.90; 95% confidence interval: 1.60, 9.46; P = .003). Contrast material enhancement of plaque is more common in patients with ACS than in those with stable CAD and is a significant and independent predictor of future coronary events in patients with stable CAD, suggesting that noninvasive contrast-enhanced carotid US may be used as a method for risk stratification of patients with stable CAD.