Prognostic impact of plaque echolucency in combination with inflammatory biomarkers on cardiovascular outcomes of coronary artery disease patients receiving optimal medical therapy

Objective The incremental prognostic impact on cardiovascular outcomes of assessment of carotid plaque ultrasound characteristics in addition to inflammatory biomarkers remains controversial in coronary artery disease (CAD) patients receiving optimal medical treatment. The present study prospectively compared carotid ultrasonic imaging with several biomarkers to stratify cardiovascular risk. Methods One hundred and sixty patients with angiographically confirmed stable CAD underwent carotid ultrasonography and were prospectively followed with optimal medical therapy including statins. Carotid atherosclerotic burden was assessed by mean intima-media thickness (IMT) at the far-wall from the common carotid to proximal internal carotid artery. Carotid plaque echolucency was quantified by measuring gray-scale median value (GSM). Major cardiovascular event was defined as cardiovascular death, newly developed myocardial ischemia, or cerebrovascular infarction. Results Of 154 subjects completing follow-up, 27 experienced a major cardiovascular event during a median 41-month follow-up period. Events comprised cardiovascular death ( n =6), newly developed myocardial ischemia ( n =16), and ischemic stroke ( n =5). Univariate Cox regression analysis showed C-reactive protein (CRP) and several ultrasonic parameters to be significant determinants for cardiovascular events. Multivariate Cox analysis determined CRP and plaque echolucency to be independent variables predicting cardiovascular events after adjustment for classic CAD risk factors. In Kaplan–Meier plots, patients with both high CRP (≥1.0mg/L) and echolucent plaque (GSM≤65) showed higher event rates than did patients with high CRP but without echolucent plaque. Conclusion Ultrasonic findings of echolucent carotid plaque may have incremental prognostic impact on risk assessment by CRP in CAD patients receiving contemporary optimal medical therapy.