Features of Unstable Carotid Plaque During and After the Hyperacute Period Following TIA/Stroke

Vascular Surgery Group, Department of Cardiovascular Sciences, University of Leicester, LE2 7LX, UK. Electronic address: .
European journal of vascular and endovascular surgery: the official journal of the European Society for Vascular Surgery (Impact Factor: 2.49). 12/2012; 45(2). DOI: 10.1016/j.ejvs.2012.11.023
Source: PubMed


BACKGROUND: The aim was to test the hypothesis that histologically unstable carotid plaque features were more prevalent in patients undergoing carotid endarterectomy (CEA) in the acute period after onset of symptoms and that the plaque would assume more stable histological characteristics as the delay from the most recent event increased. METHODS: Seven histological features of plaque instability (haemorrhage, large lipid core, chronic plaque inflammation, chronic cap inflammation, marked vascularity, cap rupture and many foam cells) were independently quantified and then correlated with recency of symptoms in patients undergoing CEA. RESULTS: In patients undergoing CEA ≤14 days of their last event, 87/119 (73%) exhibited ≥5/7 unstable histological plaque features, compared with 22/40 (55%) of patients undergoing delayed surgery (P = 0.048). As expected, there was a sustained decline in the prevalence of unstable plaque features in 61 patients undergoing surgery between days 7-28. However, there was then a marked increase in the prevalence of plaque haemorrhage (59% up to 65%), large lipid core (41% up to 78%), chronic plaque inflammation (71% up to 91%), cap rupture (35% up to 39%), many foam cells (24% up to 43%) and marked vascularity (71% up to 91%) in 23 patients undergoing CEA after 29 days had elapsed. CONCLUSION: Patients undergoing surgery ≤14 days had a significantly higher overall burden of high risk plaque features compared with those undergoing delayed CEA. However, the secondary upsurge across a range of unstable plaque features in patients undergoing CEA after ≥29 days had elapsed suggests that the relationship between recency of symptoms and plaque histology is more complex than had been anticipated in previous studies.

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Available from: Ross Naylor, Jul 17, 2014
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    • "Currently, clinical non-invasive ultrasound-based methods for plaque characterization are limited to visual assessment of plaque morphology, hypoechoic area, and echo reflection in the plaque (Gray-Weale et al 1988, Kakkos et al 2013). There have been quantitative plaque characterization attempts by grey-scale median (GSM) measurements of the plaque (Biasi et al 1999, Kanber et al 2013, Salem et al 2013) as well as using contrast-enhanced ultrasound imaging in combination with Tissue Doppler imaging (Deyama et al 2013), however both techniques suffer from various limitations. Thermal Strain Imaging (TSI) has also been used in vivo to detect lipids in atherosclerotic plaques in the femoral arteries of rabbits (Mahmoud et al 2013) but the technique is not ready for clinical use. "
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