Novel serum biomarkers in carotid artery stenosis: Useful to identify the vulnerable plaque?

Objectives: Serum biomarkers representing inflammatory activity in vulnerable carotid plaques may be used to identify high-risk patients for cerebral ischemic events. We aimed to analyze the relationship between concentrations of four novel biomarkers and neurological symptoms: Neopterin, PTX3, sCD163, and sTREM-1. In addition, we analyzed the relationship between these markers and the presence of coronary (CAD) and peripheral (PAD) artery disease. Design and methods: Serum biomarker levels were determined in 100 patients undergoing carotid endarterectomy: 33 for stroke, 32 for transient ischemic attack, and 23 for amaurosis fugax. 12 Patients were asymptomatic. Risk factors for atherosclerotic disease and history of CAD and PAD were also assessed. Results: Symptomatic patients did not show significantly elevated biomarker levels compared to asymptomatic patients and levels did not differ among symptomatic subgroups. Neopterin levels were elevated in patients with concomitant coronary and peripheral artery disease (CAD (32%) 10.2 +/- 6.6 vs no CAD (68%) 7.6 +/- 2.9 nmol/L, PAD (20%) 12.3 +/- 7.4 vs no PAD (80%) 7.5 +/- 3.0 nmol/L, p<0.05). sTREM-1 was elevated in patients with CAD (50.8 +/- 53.2 vs 28.0 +/- 31.6 ng/L, p < 0.05). PTX3 and sCD163 were not significantly elevated in CAD nor PAD. Conclusion: Our findings suggest that serum neopterin and sTREM-1 levels may be related to the presence of atherosclerotic disease, but not to carotid plaque vulnerability. (C) 2011 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.