Detection of Unstable Plaques in Patients with Carotid Stenosis Using B-Mode Ultrasonography

Abstract

<jats:p> Distal embolism is a detrimental complication of stent placement for the carotid artery stenosis. To evaluate usefulness of B-mode ultrasonography (US) for the detection of unstable plaques in patients with carotid artery stenosis, we examined US in 46 arteries of 35 patients with carotid stenosis of &gt;30%. </jats:p><jats:p> The echogenicity of 46 carotid plaques was hyperechoic in 20 plaques, hypoechoic in 15, and mixed-echoic in 11. The echogenicity of carotid plaques was correlated with severity of carotid stenosis, ipsilateral stroke or T1A, heart attack, and risk factors of systemic atherosclerosis. Hypoechoic plaques were associated with severe carotid stenosis and ipsilateral ischemic event. Mixed-echoic plaques had a high incidence of past history of heart attack. Hyperechoic plaques were less likely to associate with risk factors of systemic atherosclerosis. </jats:p><jats:p> We developed a new method of echodensity analysis. Using a computer software, echodensity values of seven plaque components were determined by comparing US findings and pathology of surgical specimens. The echodensity value was defined as a relative value to the arterial lumen. </jats:p><jats:p> The calcified part of plaques had the highest echodensity of 6.24 ± 0.86 (mean ± 2 S.D.); fibrosis or hyarynoid degeneration of 2.05 ± 0.40, foamy histiocytes of 1.47 ± 0.05, necrosis of 1.32 ± 0.16, cholestelin clefts of 1.28 ± 0.13, intraplaque hemorrhage of 1.02 ± 0.09, and intraluminal thrombus of 1.27 ± 0.07. Constructed from the echodensity value, an echo-densitometry color mapping of the carotid plaque illustrated the exact location and extent of plaque component. B-mode US of carotid plaques represents clinical characteristics relating distal embolism and systemic atherosclerosis. A new method of echodensity analysis and echo-densitometry color mapping of the carotid plaque is useful to detect unstable plaques in patients with carotid stenosis. </jats:p>

Cytochrome P450 Genetic Variants and Their Metabolite Levels Associated with Plaque Stability in Patients with Ischemic Stroke

“…Some studies have also shown that CYP450 plasma metabolite levels are associated with IS risk 17) , but few studies have focused on subclinical atherosclerosis. Certain carotid plaque phenotypes such as plaque instability may be important markers of vulnerable plaques susceptible to rupture, leading to stroke 21) . To our knowledge, our study is the first to investigate the association between the genetic variations of genes related to the CYP pathway and possible markers of vulnerable plaque or the effect of these genetic variants on CYP450 plasma echolucent plaques, indicating that these SNPs may be potential markers for plaque instability.…”

“…Bilateral internal and common carotid arteries, as well as bifurcations, were examined for atherosclerotic plaque presence and was defined as an endoluminal protrusion of at least 1.5 mm or a focal thickening 50% of the intima-media thickness relative to the adjacent wall segment 11,21) . Thereafter, patients were divided into two groups: carotid plaque and noncarotid plaque groups.…”

Genetic variants of PTGS2, TXA2R and TXAS1 are associated with carotid plaque vulnerability, platelet activation and TXA2 levels in ischemic stroke patients

“…Carotid plaque was defined as an endoluminal protrusion of at least 1.5 mm or a focal thickening >50% of the intima-media thickness relative to the adjacent wall segment [7,25]. According to the results, the patients were divided into two groups: carotid plaque and non-carotid plaque groups.…”

Rationale, Design, and Methodological Aspects of the BUDAPEST‐GLOBAL Study (Burden of Atherosclerotic Plaques Study in Twins—Genetic Loci and the Burden of Atherosclerotic Lesions)

“…The visualizable portions of the deep femoral artery and the superficial femoral artery were also assessed bilaterally. Endoluminal protrusions of ≥1.5 mm or a focal thickening >50% of the intima‐media thickness relative to the adjacent wall segment were considered plaques . In case of a plaque, we measured the plaque‐free arterial wall adjacent to the plaque.…”