China
Africa
Explore chapters and articles related to this topic
Clinical Effects of Pollution
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 5, 2017
William J. Rea, Kalpana D. Patel
The vasa vasorum are specialized vessels. All types of arterial vasa vasorum (AVV) are recognized. The first type is the vasa vasorum interna, which originate from the large vessel going to the378 media359,379 and branching out into the adjacent artery wall.380 The second type is the vasa vasorum externa, which are found primarily in the adventitia at its border with the media. They originate from various anatomic locations like the nearby major branches (external vasa vasorum) of the large vessel. These small vessels nourish the larger vascular wall and clean them of toxic substances and debris. These vasa vasorum include the brachiocephalic and coronary arteries in the ascending aorta, the intercostal branches in the descending thoracic aorta, the lumbar and mesenteric arteries in the abdominal aorta, and bifurcation segments of epicardial vessels in coronary arteries.381 These vessels supply nutrients and oxygen to the arterial walls and microcirculation and help detoxify substances (Figure 2.19).
Cardiovascular system
Published in A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha, Clark’s Procedures in Diagnostic Imaging: A System-Based Approach, 2020
A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha
The aorta is the largest artery in the human body and transports oxygenated blood from the heart to the rest of the body. The thoracic aorta consists of the ascending, arch and descending aorta. There are three major branches from the thoracic aorta, all from the aortic arch: the brachiocephalic, left common carotid and left subclavian arteries. The aorta passes into the abdomen through the diaphragmatic hiatus at T12. The abdominal aorta has three ventral branches (coeliac axis, superior mesenteric and inferior mesenteric arteries) and two lateral branches (right and left renal arteries).
Flow disturbance around dynamically interacting aortic junctions
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2019
A. I. Barakat, G. Vilaplana, T. Seo
The preferential development of atherosclerotic lesions near arterial branches and bifurcations suggests that localizing factors such as fluid mechanical disturbances are involved in the etiology of the disease. Numerous experimental and computational studies of arterial flow fields have demonstrated the highly dynamic nature of flow disturbance at arterial branches (Karino et al. 1990; Cheer et al. 1998). In the aorta in vivo, major branches are often in close anatomic proximity and thus interact fluid mechanically with one another. A prominent example where atherosclerotic lesions are prevalent is in the abdominal aorta where two major branches, the celiac and superior mesenteric arteries, emerge from the aorta along the ventral wall to form T-junctions. Interestingly, the spacing between these two branches varies significantly among individuals and across species, and this spacing is expected to have a profound impact on the fluid mechanical interactions between the two branches and thus on the overall flow field in the abdominal aorta. How fluid mechanical interactions between two aortic branches modulate flow disturbance in the vicinity of each branch remains incompletely understood. The goal of the present study is to computationally investigate the effect of fluid mechanical interactions between the celiac and superior mesenteric arteries on the local flow field and wall shear stress distribution.