Contrast-enhanced ultrasound imaging of intraplaque neovascularization in carotid arteries: correlation with histology and plaque echogenicity.

Abstract

OBJECTIVES:

This study was designed to evaluate contrast-enhanced ultrasound imaging of carotid atherosclerosis as a clinical tool to study intraplaque neovascularization.

BACKGROUND:

Plaque neovascularization is associated with plaque vulnerability and symptomatic disease; therefore, imaging of neovascularization in carotid atherosclerosis may represent a useful tool for clinical risk stratification and monitoring the efficacy of antiatherosclerotic therapies.

METHODS:

Thirty-two patients with 52 carotid plaques were studied by standard and contrast-enhanced ultrasound imaging. In 17 of these patients who underwent endarterectomy, the surgical specimen was available for histological determination of microvessel density by CD31/CD34 double staining. Plaque echogenicity and degree of stenosis at standard ultrasound imaging were evaluated for each lesion. Contrast-agent enhancement within the plaque was categorized as absent/peripheral (grade 1) and extensive/internal (grade 2).

RESULTS:

In the surgical subgroup, plaques with higher contrast-agent enhancement showed a greater neovascularization at histology (grade 2 vs. grade 1 contrast-agent enhancement: median vasa vasorum density: 3.24/mm(2) vs. 1.82/mm(2), respectively, p = 0.005). In the whole series of 52 lesions, echolucent plaques showed a higher degree of contrast-agent enhancement (p < 0.001). Stenosis degree was not associated with neovascularization at histology or with the grade of contrast-agent enhancement.

CONCLUSIONS:

Carotid plaque contrast-agent enhancement with sonographic agents correlates with histological density of neovessels and is associated with plaque echolucency, a well-accepted marker of high risk lesions, but it is unrelated to the degree of stenosis. Contrast-enhanced carotid ultrasound imaging may provide valuable information for plaque risk stratification and for assessing the response to antiatherosclerotic therapies, beyond that provided by standard ultrasound imaging.

• Authors: Stefano Coli, Marco Magnoni, Giuseppe Sangiorgi, Massimiliano M Marrocco-Trischitta, Giulio Melisurgo, Alessandro Mauriello, Luigi Spagnoli, Roberto Chiesa, Domenico Cianflone, Attilio Maseri
• Journal: Journal of the American College of Cardiology (J Am Coll Cardiol) Vol. 52 Issue 3 Pg. 223-30 (Jul 15 2008) ISSN: 1558-3597 [Electronic] United States
• PMID: 18617072 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Contrast Media

Topics

• Aged
• Carotid Arteries (diagnostic imaging, pathology, surgery)
• Carotid Stenosis (diagnostic imaging, pathology, surgery)
• Contrast Media
• Endarterectomy
• Female
• Health Status Indicators
• Humans
• Immunohistochemistry
• Male
• Neovascularization, Pathologic (diagnostic imaging, surgery)
• Risk Assessment
• Ultrasonography