門脈圧亢進症の血行動態（左側門亢症も含めて）

Hemodynamics of portal hypertension including sinistral subtype

要旨

門脈系循環が障害されると，正常門脈圧においては本来存在しても無視しうる細い門脈系-大循環系交通路が拡張し，脾腫を伴って年月の経過とともにsplanchnic caput Medusae（SCM）なる形態変化をきたしてくる。SCMは，脾動静脈血流量増加という局所循環亢進状態と，全身血管抵抗の減少，心拍出量の増加，動静脈血酸素含量較差狭小化という全身循環亢進状態を伴いさまざまな病態とリンクしてくる。門脈圧亢進症における治療目標は，まずは消化管静脈瘤の出血制御であり，次に脾腫対策を含めた門脈圧制御，そして脳症や循環異常の是正を含めた門脈圧亢進症全体の系統的制御である。一般消化器内視鏡医にはSCMなる形態変化を伴う門脈圧亢進症血行動態の正しい理解と，脾腫対策を含めた体系的治療の理解が求められる。

　When portal circulation is impaired, the narrow portosystemic circulation channels, which are negligible under normal portal venous pressure, dilate, causing splenomegaly. Over time, a morphological change called splanchnic caput Medusae (SCM) occurs. SCM is linked to various pathological conditions, including a local hyperdynamic state of increased splenic arteriovenous blood flow volume and a systemic hyperdynamic state of decreased systemic vascular resistance, increased cardiac output, and narrowed arteriovenous blood oxygen content difference. The treatment goal for portal hypertension is first to control bleeding from gastrointestinal varices, then to control portal venous pressure and splenomegaly, and then to systematically control the entire portal hypertension including encephalopathy. General gastrointestinal endoscopists are required to correctly understand the hemodynamics of portal hypertension accompanied by morphological changes known collectively as SCM, and to understand systematic treatment including measures against splenomegaly.