Assessment of inflammatory infiltration and angiogenesis in the thrombus and the wall of abdominal aortic aneurysms on the basis of histological parameters and computed tomography angiography study

Abstract

Abstract:The proliferation of vessels within the aneurysm's wall and the intraluminal thrombus of abdominal aortic aneurysm (AAA) may be the main factor responsible for progression and rupture of AAA. The aim of this study was to compare the parameters of the thrombus (size, density, contrast enhancement) measured by computed tomography (CT) with histological assessment of thrombi removed during surgery. 29 patients with AAA were examined with angio-CT. Post-surgery histopathological evaluation of AAA was performed. Slides were stained with markers of B-(CD20) and T-lymphocytes (CD3), and markers of endothelial cells (CD34). Thrombi were enhanced after contrast media administration in angio-CT (p = 0.002). There was a statistically significant correlation between contrast enhancement and the presence of B lymphocytes. Intensity of endothelial cell marker expression significantly correlated with the presence of inflammatory T-and B-cells. No statistical significant correlation was found between contrast enhancement of the thrombus and markers of endothelial cells. The accumulation of inflammatory cells in the wall of AAA thrombus results in the formation of new vessels which participates to the instability of the thrombus and AAA wall. Assessment of the inflammation and neovascularization in the wall and thrombus of the AAA might be an important factor in monitoring the progression and the risk of aneurysm's rupture.

Plasma cytokine levels and risks of abdominal aortic aneurysms: A population-based prospective cohort study

“…Instead, both plasma IFN-γ and IL17A levels correlated significantly and positively with a maximal cross-sectional area in a multivariate Pearson's correlation analysis when only 476 AAA patients were considered (Table 5). AAA formation includes both aortic wall expansion and inflammatory cell infiltration and proliferation, which are responsible for enlarged aortic diameters and lesion inflammation (47, 48). Reduced plasma IFN-γ and IL17A in AAA patients (Figure 1), insignificant correlation of these cytokines to maximal aortic diameters (Table 4), but positive and significant correlation with maximal cross-sectional AAA areas among 476 AAA patients (Table 5) suggest that enriched inflammatory cells in AAA lesions and possibly in the peripheral from this AAA population are responsible, at least in part, for plasma IFN-γ and IL17A from AAA patients, although this hypothesis was not tested in this study.…”

Evaluation of the thrombus of abdominal aortic aneurysms using contrast enhanced ultrasound - preliminary results

“…suggested that inflammatory cells in AAA thrombus may lead to vessel wall impairment and the increased the risk of aneurysm rupture 22 . Our previous results showed inflammatory cells infiltration accompanied by intensive angiogenesis within the AAA thrombus 24 . The proliferation of small vessels within the aneurysm wall and in the intraluminal thrombus may decrease the integrity and stability of AAA wall and be one of the factors responsible for both progression and increased risk of AAA rupture 8 .…”

C-reactive protein deficiency ameliorates experimental abdominal aortic aneurysms

“…Angiogenesis, an additional key AAA pathology, also contributes to the progression of AAAs ( 35 , 36 ). Angiogenesis, as determined by the density of CD31 + neovessels, was not differentiated between CRP -/- (50.82 ± 13.40/ACS) and WT (43.90 ± 12.23/ACS) mice ( Figure 5 ).…”