Vasa vasorum

See color plate.) The development of neovascularization in a hypercholesterolemic model is shown in the right panel. The density of vasa vasorum in the aortic wall is clearly increased after administration of hypercholesterolemic diet, compared with the control group [leftpanel). Arrows indicate the vasa vasorum. Source From Ref. 72. 

Williams JK, Armstrong ML, Heistad DD. Vasa vasorum in atherosclerotic coronary arteries responses to vasoactive stimuli and regression of atherosclerosis. Circ Res 1988 62 515-523. 

Hayden MR, Tyagi SC. Vasa vasorum in plaque angiogenesis, metabolic syndrome, type 2 diabetes mellitus, and atheroscle-ropathy a malignant transformation. Cardiovasc Diabetol 2004 3 1. 

PC coated stent for inhibition of vasa vasorum of atherosclerotic plaque angiographic results in a rabbit atheromatic model. Hellenic J Cardiol 2006 47 7-10. 

Barger AC, Beeuwkes R, Lainey LL, Silverman KJ. Hypothesis vasa vasorum and neovascularization of human coronary arteries. A possible role in the pathophysiology of atherosclerosis. N Engl J Med 1984 3 10(3) 175-177. 

Wilson SH, Herrmann J, Lerman LO, Holmes DR, Napoli C, Lerman A. 2002. Simvastatin preserves the structure of coronary adventitial vasa vasorum in experimental hypercholesterolemia in-dipendent of lipid lowering. Circulation 105 415-18... 

M. Gossl, N. M. Malyar, M. Rosol, P. E. Beighley and E. L. Ritman, Impact of coronary vasa vasorum functional structure on coronary vessel wall perfusion distribution, Am J Physiol Heart Circ Physiol 285, H2019-H2026 (2003). 

A clinically relevant phenomenon is described in Chapter 5. Coronary microembolization which is a frequent event in ischemic heart disease due to plaque ruptures may compromise the microcirculation with subsequent events such as arrhythmias, cardiac dysfunction, infarcts and reduced coronary reserve. Furthermore, microembolization of coronary vasa vasorum may contribute to plaque instability and propagation of atherosclerosis into the more distal coronary vascular tree. Microembolization may offer an interpretation for some unexplained manifestations of ischemic heart disease in clinical practice. 

The normal artery is composed of three distinct layers (Fig. 34.21). That which is closest to the lumen of the vessel, the intima, is lined by a monolayer of endothelial cells that are bathed by the circulating blood. Just beneath these specialized cells lies the subintimal extracellular matrix, in which some vascular smooth muscle cells are embedded (the subintimal space). The middle layer, known as the tunica media, is separated from the intima by the internal elastic lamina. The tunica media contains lamellae of smooth muscle cells surrounded by an elastin- and collagen-rich matrix. The external elastic lamina forms the border between the tunica media and the outermost layer, the adventitia. This layer contains nerve fibers and mast cells. It is the origin of the vasa vasorum, which supply blood to the outer two thirds of the tunica media. 

A well-developed tunica adventitia and vasa vasorum, although wall layers are gradually thinning) ... 

Wall morphology Essentially the same as comparable major arteries but a much thinner tunica intima, a much thinner tunica media, and a somewhat thicker tunica adventitia contains a vasa vasorum... 

The bronchial arteries supply the trachea, pulmonary airways (both intra- and extrapulmonary), regional lymph nodes, (visceral) pleura, esophagus, and vasa vasorum of aorta and pulmonary artery and vein. 

The results for treated blood vessels showed that after 4 weeks, the BASYC -prosthesis was wrapped up with connective tissue, pervaded with small vessels like vasa vasorum. The BASYC -interposition was completely incorporated in the body without any rejection reaction. Results from micronerve surgery (white rat sciatic nerve) showed similar results. From 4 to 26 weeks following the intervention, the bacterial cellulose tube was covered with connective tissue and contained small vessels. No inflammation reaction or capsulation of the implant was observed. The regeneration nerve was improved after 10 weeks, compared to an uncovered anastomosed nerve. 

The periarterial plexus lies in the adventitia of the arteries, and its bundles anastomose with those of the extrachondral plexus. Fibres of the arterial plexus enter the media with the vasa vasorum and supply its outermost portion. The plexus continues distally as far as the arterioles. 

Originally, IMH was defined as a dissection of the aortic wall without intimal tear. The pathogenesis includes rupture of the vasa vasorum, structural aortic wall fatigue, and loss of residual strain, leading to mechanical failure. Other clinicians doubted the missing intimal tear. Rather, they postulated that an intimal tear exists. 

Complete tunica adventitia, external elastic lamina, tunica media, internal elastic lamina, tunica intima, subendothelium, endothelium, and vasa vasorum vascular supply Main branches 32 5 mm-2.25 cm 3.3-6 cm —2 mm 83.2 ml... 

Peripheral neuropathy, due to involvement of the vasa vasorum, is noted in 30% to 43% of patients during the course of the disease (3,5,79-81,91). Most common manifestations include mononeuritis multiplex or polyneuritis (3,5,79). Peripheral neuropathy is more common in males, older age, greater extent of disease, and higher titers of ANCA (79). In some patients, biopsy of the sural nerve or other affected nerves may substantiate the diagnosis. Both peripheral and CNS manifestations may be associated with irreversible damage, persisting even after the acute inflammation is adequately controlled. 

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