患者における自発性心房細動の間,心筋収縮性は一定ではない
C I Brookes1, P A White, M Staples
1National Heart and Lung Institute, Imperial College School of Medicine,Royal Brompton and Charing Cross Hospitals, London, UK.
Circulation
|October 27, 1998
まとめ
動脈動では,筋動脈の収縮性がビート・トゥ・ビートに変化し,シヌスリズムとは違います. この変動は,力-間隔関係が心臓に及ぼす影響によるものです.
科学分野:
- 心臓病学 心臓病学
- 心臓電気生理学 心臓電気生理学
- 心不全に関する研究
背景:
- 動脈動 (AF) は通常,変数の脳卒中量と脈圧を示します.
- この変動は,しばしば単に心室の埋着の変化に起因する.
- この研究では,心筋収縮性がAFでも変動するかどうかを調査しています.
研究 の 目的:
- 心筋の収縮性が心房細動の患者でビートからビートに変化するという仮説を検証する.
- AF患者における終末シストリック圧力と体積の関係と,副鼻腔リズムにおける対照群を比較する.
主な方法:
- 左心室の圧力と体積は,導電性カテーテルを使用して継続的に測定されました.
- エンドシストリック圧力と体積の関係については,AF患者6名と対照患者4名で分析した.
- フォース・インターバル関係,機械的還元,エクストラシストリック後増強なども評価された.
主要な成果:
- シヌスリズムによる対照群の患者は,正常に正の終末シストリック圧力と体積の関係を示した.
- AFの患者は一貫したポジティブな関係を示さなかったが,傾きはゼロに近いか負のもので,収縮性の変化を示していた.
- 末期シストリック容量と前回のRR区間 (機械的還元) の間の有意な負の相関.
- 末期シストリック体積と前期R-R区間 (後期エクストラシストリック増強) の間に有意な正の相関がある.
結論:
- 心筋動では心筋動の収縮性が一定ではない.
- 収縮性のビート・トゥ・ビート・バリエーションは,力-間隔関係によって引き起こされます.
- 発見は,AFの血液動力学的変動を,心室の埋着にのみ起因する伝統的な見解に異議を唱える.
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