The vasa vasorum density of thoracic aorta in the aneurism formation

Background and Aims : Damaged connective tissue structures and cystic degeneration of the medial layer can play a primary role in the pathogenesis of the thoracic aorta aneurysm. The underlying mechanisms remain poorly studied. The aim of the study was to examine the vasa vasorum density and endothelium cells abundance in tunica adventitia under the presence/absence of inflammatory infiltrates in the aortic wall.Methods: Histological samples were obtained from 30 patients of both genders aged 37 to 82 years. Histological analysis is performed by examining a thin slice of thoracic aortic aneurysm tissue with an optical microscope. IHC staining was performed using monoclonal antibodies against coagulation factor VIII, and NO synthase (eNOS), and T-lymphocytes (CD3 and CD4 antigens).Results: Examination of histological slides of thoracic aorta aneurism allowed to reveal significant infiltration of lymphocytic cells (n = 6) in the arterial wall, and a high density of vasa vasorum adventitia endothelial cells, expressing VIII factor and nitric oxide synthase. The number of vasa vasorum endothelium cells expressing NO synthase and VIII factor was equal.Conclusions: There may be a direct correlation between the number of vasa vasorum in the tunica adventitia of the thoracic aorta aneurysm and the degree of its infiltration by immunocytes. Secondary angiogenesis may play an important role in the remodeling of the arterial wall during the aortic aneurysm progression. This work was supported by Russian Science Foundation (Grant #20-45-08002). Background and Aims : Damaged connective tissue structures and cystic degeneration of the medial layer can play a primary role in the pathogenesis of the thoracic aorta aneurysm. The underlying mechanisms remain poorly studied. The aim of the study was to examine the vasa vasorum density and endothelium cells abundance in tunica adventitia under the presence/absence of inflammatory infiltrates in the aortic wall. Methods: Histological samples were obtained from 30 patients of both genders aged 37 to 82 years. Histological analysis is performed by examining a thin slice of thoracic aortic aneurysm tissue with an optical microscope. IHC staining was performed using monoclonal antibodies against coagulation factor VIII, and NO synthase (eNOS), and T-lymphocytes (CD3 and CD4 antigens). Results: Examination of histological slides of thoracic aorta aneurism allowed to reveal significant infiltration of lymphocytic cells (n = 6) in the arterial wall, and a high density of vasa vasorum adventitia endothelial cells, expressing VIII factor and nitric oxide synthase. The number of vasa vasorum endothelium cells expressing NO synthase and VIII factor was equal. Conclusions: There may be a direct correlation between the number of vasa vasorum in the tunica adventitia of the thoracic aorta aneurysm and the degree of its infiltration by immunocytes. Secondary angiogenesis may play an important role in the remodeling of the arterial wall during the aortic aneurysm progression. This work was supported by Russian Science Foundation (Grant #20-45-08002).