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Cardiac Pressure-Volume Loop Analysis Using Conductance Catheters in Mice
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イソボラム収縮中の心筋加速:収縮性との関係
Erik Lyseggen1, Stein Inge Rabben, Helge Skulstad
1Institute for Surgical Research and Department of Cardiology, Rikshospitalet University Hospital, Oslo, Norway.
Circulation
|March 9, 2005
まとめ
心筋の同体積加速 (IVA) は,地域的な心筋の収縮性を確実に反映するものではありません. この測定は負荷に依存しており,イシュケミア中の収縮性ではなく,遅期ダイアストリックイベントを示す可能性があります.
科学分野:
- 心臓病学 心臓病学
- 生理学 生理学とは
- バイオメディカルエンジニアリング
背景:
- イソボリューム収縮中のミトラリング加速は,全左心室 (LV) 収縮の負荷独立指数として提案されました.
- この研究は,心筋のイソボリューム加速度 (IVA) が地域収縮性を反映しているかどうかを決定することを目的とした.
研究 の 目的:
- 心筋のイソヴォルミック加速 (IVA) と地域左心室 (LV) の収縮性との関係を調査する.
- IVAの負荷依存度を評価する.
- イシュケミア中の地域性心筋機能不全の検出におけるIVAの有用性を評価する.
主な方法:
- 麻酔を受けた犬の組織ドップラー画像 (TDI) とソノミクロメトリーを使用して,LV圧力,心筋長軸速度,およびIVAの測定.
- グローバルLV収縮性 (ドブタミン) とプレロード (ボリュームロード) の操作.
- 左前垂下冠動脈の流れを減らすことにより,地域性心筋不全の誘導.
主要な成果:
- ドブタミンは,IVAとLV dP/dtmaxを並行して増加させた.
- ボリューム負荷はIVAを低下させたが,LV dP/dt (最大) や地域収縮性は変化しなかった.
- 地域性缺血は地域機能を低下させ,IVAは変化しなかった.
- TDIとソノミクロメトリーによるIVA測定は一貫した結果を出しました.
結論:
- ピークIVAは,地域性心筋収縮性との一貫した関係を示さなかった.
- ピークIVAは著しく負荷依存でした.
- ピークIVAは,イシュケミア中の心筋動脈機能障害を反映していない.
- ピークIVAは,後期ダイアストリックイベントと壁の振動によって影響を受け,地域性心筋機能の評価におけるその使用を制限する可能性があります.
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