左心室アシスタンス後の正常化された腹動質の特性は,室内幾何学の逆転改造の結果である
A Barbone1, M C Oz, D Burkhoff
1Department of Surgery, Columbia University, New York, NY, USA.
Circulation
|September 25, 2001
まとめ
左心室 (LV) 補助は,組織の硬さを変化させることによってではなく,心臓のサイズを小さくすることによって,下痢性特性を正常化します. この幾何学的な改造は,LVアシストデバイスのサポートの後,ダイアストリック機能の改善の鍵です.
科学分野:
- 心血管生理学 心血管の生理学
- バイオメディカルエンジニアリング
- 心不全に関する研究
背景:
- 立方体機能不全は,心不全の特徴である.
- 左心室 (LV) アシストデバイスは,心不全を支えるために使用されます.
- LVアシスト後のダイアストリック特性の正常化は観察されていますが,その基礎となるメカニズムについては議論されています.
研究 の 目的:
- LVアシスト後の改善されたLVダイアストリック特性は,主に室内幾何学の改造によるものであるという仮説を検証する.
- 心筋膜の物質特性の変化と幾何学的変化を区別する.
主な方法:
- 拡張性心筋症 (DCM) の心臓移植患者からの心臓の分析,LVアシストとなし.
- パッシブな圧力-体積曲線と室の寸法を測定する.
- 中壁の張力-伸縮関係の計算と,トラベキュラにおける受動的張力-伸縮関係の測定.
- 筋細胞のサイズとコラーゲン領域分数の組織学的な分析.
主要な成果:
- LVアシストは,正常化された受動的圧力-体積曲線である.
- 室の寸法は,LVアシスト後,著しく減少した.
- 中壁の張力-伸縮関係と受動的張力-伸縮関係も変わらなかった.
- 筋細胞のサイズとコラーゲン含有量は変化しませんでした.
結論:
- LVアシスト後のダイアストリック特性の早期正常化は,左心室の幾何学的な改造に起因する.
- 心筋組織の硬さの変化は,観察された静脈収縮の改善を説明しません.
- 静脈の幾何学は心臓のメカニズムにおいて重要な役割を果たし,心臓の縮小は自動的に壁のストレスを軽減するものではありません.
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