Colonic arteriovenous malformation (AVM) is one of the causes of lower GI bleeding. Unlike small vascular ectasia or angiodysplasia, colonic AVM tends to be solitary, large in size, and identified endoscopically as flat or as an elevated bright red lesion.n the case of the colon, wall tension refers to intramural tension, the pressure difference is that between the bowel lumen and the peritoneal cavity, and cylinder radius is the radius of the right colon. Wall tension is highest in bowel segments with the greatest diameter, such as the right colon.
Coagulative necrosis is the most common type of necrosis in which cells death happen after exogenous or endogenous stimuli, occurring after such stresses as ischemia, virus toxin, physical and chemical injury. It is manifested by severe cell rupture, denaturation and coagulation of cytoplasmic proteins.
Atherosclerosis is a form of chronic inflammation associated with the secretion of many cytokines, which are produced by T cells, macrophages, endothelial cells, and smooth muscle cells. Smooth muscle cells in particular produce cytokines that attract and activate leukocytes, induce proliferation of SMCs, promote endothelial cell dysfunction, and stimulate production of extracellular matrix components.