弁動脈大動脈狭窄症と左心室高縮症の患者で,ダイアストリック左心室圧力-体積とストレス-ストレスの関係
Circulation
|July 1, 1978
まとめ
バルブ性大動脈狭窄では,単に太くなるだけでなく,心筋の硬さが増加すると,腹動脈充填圧が上昇します. この硬さは,大動脈弁の置換後に逆転することがあり,それが示唆されます.
科学分野:
- 心血管生理学 心血管の生理学
- 心臓のメカニズム 心臓のメカニズム
- バイオメディカルエンジニアリング
背景:
- 弁動脈大動脈狭窄症 (AS) は,しばしば同心的左心室 (LV) ハイパルトロフィーにつながる.
- ASにおけるダイアストリック機能不全の決定因子を理解することは,患者の管理に極めて重要です.
- 心筋と心室の硬さは,ダイアストリック充填に影響を与える重要な機械的特性です.
研究 の 目的:
- バルブ性AS患者における左心室 (LV) 腔と心筋硬直の定量化.
- 集中型縮症,心筋硬化,および下静脈圧力の間の関係を調査する.
- 大動脈弁置換手術後のダイアストリック硬さの可逆性を調査する.
主な方法:
- 17人の患者でカテーテルマイクロマノメトリーとLVシネアニオグラフィーを同時に行いました (正常患者4人,AS患者13人).
- 圧力 (P),体積 (V),壁の厚さ (h) を測定する.
- 室内剛性定数 (a, a') と心筋弾性剛性 (ES, EE) と剛性定数 (KS, KE) の計算.
主要な成果:
- 5人のAS患者 (1群) は,高縮にもかかわらず,正常な腹筋硬化パラメータを示した.
- 8人のAS患者 (IIグループ) は,ダイアストリック硬度 (dP/dV,dP/dV/V,ES,EE) が著しく増加し,室内硬度が増加する傾向を示した.
- 集中型縮は,下痢圧の上昇と相関しているが,筋肉の硬さが増加すると,一部の患者ではより重度の上昇が説明される.
結論:
- 集中高縮は,壁のストレスを軽減することによって,ASにおける高気圧の主要な決定因子です.
- ハイパルトロフィーを超えた心筋硬直の増加は,AS患者の一部で重度の腹動力機能不全に寄与する.
- 大動脈弁の置換後の可逆性静脈硬化症は,補償性多動症における硬さの増大の原因が常に線維症であるとは限らないことを示唆している.
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