充填パターンの変化がダイアストリック圧力-体積曲線に与える影響
T J Fraites1, A Saeki, D A Kass
1Department of Medicine, The Johns Hopkins University, Baltimore, Md 21287, USA.
Circulation
|January 7, 1998
まとめ
心臓が満たされる方法は,粘着弾性による室圧に影響を与えます. 早期から遅い充填比 (E:A) を変化させると,終盤腹圧に大きな影響があり,リラックスや体積変化の影響を緩和する可能性があります.
科学分野:
- 心血管生理学 心血管の生理学
- ディアストロジーはダイアストロジーです.
- 心臓の生体力学的性質について
背景:
- 早期から後半の心室充填比 (E:A) は,下痢機能の重要な指標である.
- 心筋の粘弾性性は,室圧に影響を与え,充填パターンと潜在的に相互作用する可能性があります.
研究 の 目的:
- ディアストリック充填パターンが室内圧力をどのように調節するかを調査するために.
- 充填フィードバックが,緩やかなリラックスと体積の負荷がダイアストリック圧力に与える影響を和らげることができるという仮説を検証する.
主な方法:
- 隔離された血液に浸透した犬の左心房は,制御された排泄と充填のためのサーボポンプを使用して研究されました.
- ダイアストリック充填パターンは,異なるプレロード下で特定のE:A比率 (3:1, 1:3, 1:1) を達成するために操作されました.
主要な成果:
- 早期充填 (E:A=3:1) は,リラクゼーション時間常数に比例して,粘度とともに下痢圧の上昇を示した.
- この粘度-圧力の依存性は,E:A比率の低下とともに減少した.
- より高いE:A比率は,同様の体積でより低い比率と比較して,末端ダイアストリック圧力が著しく低下しました.
結論:
- ダイアストリック充填パターンは,粘着弾性を通して,早期および遅期のダイアストリック室圧に直接影響します.
- E:A比率の変化は,リラックスが遅れたり,前負荷が増加したりなどの要因がダイアストリック圧力上昇に及ぼす直接的な影響を調節することができます.
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