急性不血性左心室不全における遅滞した頂上充填のメカニズム
K Steine1, M Stugaard, O A Smiseth
1Institute for Surgical Research, Rikshospitalet, Oslo, Norway.
Circulation
|April 20, 1999
まとめ
缺血中の左心室 (LV) の頂上充填の遅延は,ミトラルから頂上への圧力の低下と関連しています. これは,より遅い LV のリラックスと,充填パターンの変化を示しています.
科学分野:
- 心血管生理学 心血管の生理学
- エコーカルディオグラフィー エコーカルディオグラフィー
- 心不全に関する研究
背景:
- ドップラー心声撮影を用いて左心室 (LV) の頂上充填を評価する.
- 頂点填充と心室内圧差の間の関係を調査する.
研究 の 目的:
- 病気のLVのアピカル充填が遅くなったことが,ミトラルからアピカルへの圧力グラデントが低下していることを示すかどうかをテストする.
- イシュケミア中のLV補充の障害の背後にある生理学的メカニズムを探求する.
主な方法:
- 9匹のオープンチェスト犬のカラーMモードドップラーエコーカルディオグラフィとマイクロマノメーターを使用した.
- 冠動脈マイクロエンボリゼーションによる誘発された急性性性高血性LV不全.
- 流れの伝播とLV圧縮の測定時間遅延 (TD) (tau).
主要な成果:
- 血栓不全症は,LVの終末ダイアストリック圧力を有意に増加させ,エジェクション分数を減少させた.
- ミトラルからアピカルまでの圧力梯度 (DeltaPLVmitral-apex) は低下し,TDは著しく増加した.
- TDは,圧力の傾斜の減少とタウの増加と強く相関しており,緩やかなリラックスを示しています.
結論:
- ミトラルからアピカルへのドライビングプレッシャーの低下は,発血性LV不全におけるアピカル充填の遅延を引き起こし,リラクゼーションの障害を反映します.
- 変化したフローの伝播は,イシュケミア中にコラム運動からコンベクションが支配する充填にシフトします.
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