左心室機能不全を有するヒトにおけるレボシメンダンの直接的な心筋効果:力-周波数およびリラックス-周波数関係の変化
Michael M Givertz1, Costa Andreou, Chester H Conrad
1Cardiomyopathy Program and Cardiovascular Section, Boston University Medical Center, Boston, Mass, USA. mgivertz@partners.org
Circulation
|March 7, 2007
まとめ
レボシメンダン (Levosimendan) は,カルシウム感受剤であり,心不全の患者に軽度のイノトロピーおよびルシトロピー効果を提供します. 動力-周波数またはリラックス-周波数関係を変化させることなく,シストリックおよびダイアストリック機能を改善します.
科学分野:
- 心臓病学 心臓病学
- 薬理学 薬理学とは
背景:
- カルシウム感受剤は心不全の治療のために研究されているが,リラックス障害に関する懸念がある.
- レボシメンダンは,トロポニンCと結合することで,ミオフィラメントのカルシウム感受性を高め,インビトロで陽性なイノトロピーおよびルシトロピー効果を示します.
- ヒトの心不全 (ミオカルディアム) に対するレボシメンダンの直接的な効果を in vivo で調べることは極めて重要です.
研究 の 目的:
- 左心室機能不全のある人の心臓のシストリックおよびダイアストリック機能に対するレボシメンダンのインビボ効果を決定する.
- レボシメンダンの効果が心拍数に依存しているかどうかを評価する.
主な方法:
- 非乳房性伸縮性心筋症の10人の患者は,左心室カテーテル治療と右心房パスを受けました.
- 冠内レボシメンダンが投与され,イノトロピー (+dP/dt) とルシトロピー (Tau) の応答は,様々な心拍数で測定されました.
- コントロールの測定は,冠内塩素注入で行われました.
主要な成果:
- レボシメンダンはピーク+dP/dtを増加させ,様々な心拍数において,投与量に依存した方法でタウを減少させた.
- アトリアルペースだけでタウを低下させましたが,+dP/dtを増加させませんでした.
- レボシメンダンは,力-周波数またはリラックス-周波数関係を変化させなかった.
結論:
- レボシメンダンによる心筋カルシウム感受化は,左心室機能不全を有するヒトにおいて,軽度のイノトロピーおよびルシトロピー効果を提供します.
- レボシメンダンのシストリック機能とダイアストリック機能に対する有益な効果は,心拍数変化によって調節されません.
- この薬は,衰弱しているヒト心筋の固有の力-周波数またはリラックス-周波数ダイナミクスを変化させない.
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