Plaque features linked with worse fibrous cap status
MedWire News: The size of the lipid-rich necrotic core (LRNCs) and the presence of hemorrhage are independently associated with the vulnerability of atherosclerotic plaque to rupture, in vivo imaging of the carotid artery suggests.
Large LRNCs and hemorrhage were independently associated with a worse fibrous cap status in carotid arteries with mild-to-severe stenosis in the magnetic resonance imaging (MRI) study.
Chun Yuan (University of Washington, Seattle, USA) and colleagues say their findings “reveal part of the process of atherosclerosis progression.”
They add: “Because fibrous cap rupture is considered a critical factor for subsequent thromboembolic events, the present results provide important information for the management of patients with carotid artery atherosclerosis.”
The team studied 77 patients with 50% or more carotid stenosis in at least one side by duplex ultrasound who underwent bilateral multi-contrast carotid MRI scans.
Measurement of wall and LRNC size, assessment of hemorrhage, and classification of the fibrous cap status as intact thick, intact thin, or ruptured were recorded.
Among 798 MRI slices studied, multivariate ordinal regression analysis demonstrated that a larger percentage of LRNC was independently associated with an intact thin or ruptured fibrous cap, with an odds ratio (OR) of 1.49 per 10% increase.
The same was true for the presence of hemorrhage, which had an OR of 5.91 for an intact thin or ruptured fibrous cap.
In artery-based multivariate analysis, a larger maximum percentage LRNC and the presence of hemorrhage were independently associated with worse fibrous cap status. No hemorrhage was detected in arteries with thick fibrous caps, the authors note.
Reporting in the journal Arteriosclerosis, Thrombosis, and Vascular Biology, they write: “These results add to the understanding of mechanism of fibrous cap destabilization which results in thromboembolic events.”
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By Anita Wilkinson