1)門脈圧亢進症

Portal Hypertension

　門脈圧亢進症による血行動態の変化は消化管壁に様々な影響を及ぼす．門脈圧亢進症により形成された側副血行路は食道・胃静脈瘤として消化管に現われる．食道静脈瘤上のred color sign陽性は出血のリスクが高く，内視鏡的食道静脈瘤硬化療法，内視鏡的食道静脈瘤結紮術による予防的，緊急時の治療が行われている．胃静脈瘤は噴門部，胃底部に形成される．いったん出血すると大量出血が起こるが，Histoacryl局注により止血されるようになった．消化管の血流うっ滞による微小循環の変化はportal hypertensive gastropathy(PHG)と称される胃粘膜所見として出現する．大腸でもportal hypertensive colopathyとして提唱されている粘膜変化や直腸静脈瘤がみられる．

　Changes in hemodynamics caused by portal hypertension exert various effects on the gastrointestinal wall. In the esophagus, collateral vessels resulting from portal hypertension manifest themselves as esophageal varices on the mucosal surface. A positive red color sign indicates a high risk of bleeding from an esophageal varix. Preventive and emergency treatment options include endoscopic injection scleropathy and endoscopic variceal ligation.

　Gastric varices form in the cardia and fornix of the stomach. Once bleeding begins, profuse blood loss results, but hemostasis can be achieved by local injection of n-butyl-2-cyanoacrylate (Histoacryl). Changes in the microcirculation caused by congested blood flow of the gastrointestinal tract manifest themselves as a gastric mucosal finding known as portal hypertensive gastropathy (PHG). Similar findings in the large intestine are the mucosal changes designated as portal hypertensive colopathy and rectal varices.