High sensitivity C-reactive protein and vascular endothelial growth factor as indicators of carotid plaque vulnerability

BACKGROUND: Carotid atherosclerotic plaques are one of the causes of cerebral stroke. The risk is higher for the vulnerable plaques but there are no specific markers to identify them. The aim of our study was to identify vulnerable carotid plaques by the mean of atherosclerotic serological markers in patients undergoing carotid revascularization by endarterectomy (CEA) or stenting (CAS). METHODS: High sensitivity C-reactive protein (hsCRP) and vascular-endothelial-growth-factor (VEGF) levels were assessed preoperatively in patients undergoing carotid revascularization. Carotid plaques vulnerability were investigated in two different methods: the "biological vulnerability" with the histological evaluation of the plaques from CEA, scoring five parameters (microvessel density, fibrous-cap-thickness, calcification, inflammatory infiltrate and lipid core), and the "structural vulnerability" with the evaluation of the plaques debris detached during CAS and captured by the cerebral protection filter, in terms of percentage of filter pores occlusion (OP). Results were correlated using x(2), Fisher's, Mann-Whitney, Student's t-tests and regression analysis. RESULTS: The histological analysis was performed in 40 specimens, vulnerable plaques (30%) were correlated with higher hsCRP levels (>5mg/1; OR, 2.5; CI 95%, 1.1-5.5; P=0.01) and VEGF levels (VEGF>500 pg/I; OR 3.0, CI 95%, 1.1-7.7; P=0.01). All the filters (N.40) contained microscopic debris (mean OP 26.6%+/- 9.9); higher hsCRP levels (>5mg/1) were correlated with greater than 25% OP (OR, 2.6; CI 95%, 1.2-5.7). An increase in the percentage of OP was also observed in patients with VEGF>500 pg/1 (OR, 2.9; CI, 95% 1.3-6.3). CONCLUSIONS: This study suggests that serological determinants are useful in recognizing the structural and biological vulnerability of carotid plaques.