終末シストリック弾性度のシングルビート推定は,時間変動弾性度曲線のバイリニア近似を用いて行う
T Shishido1, K Hayashi, K Shigemi
1Department of Cardiovascular Dynamics, National Cardiovascular Center Research Institute, Osaka, Japan. tosjoe@res.ncvc.go.jp
Circulation
|October 18, 2000
まとめ
新しい方法は,単一のビートを使用して左心室末縮弾性 (Ees) を推定し,臨床的制限を克服します. このアプローチは,容易に入手可能なデータで収縮性の評価を簡素化します.
科学分野:
- 心血管生理学 心血管の生理学
- 心臓のメカニズム 心臓のメカニズム
- バイオメディカルエンジニアリング
背景:
- 左心室末筋収縮弾性 (Ees) は,重要な収縮率指数である.
- Eesの臨床応用は,測定の難しさと負荷状態の変動によって制限されています.
研究 の 目的:
- 簡素化されたシングルビート方法を開発し,Ees.を推定する.
- 伝統的なEes測定に関連する技術的な課題を克服するために.
主な方法:
- 2つの線形関数 (同体積収縮と射出相) を用いて時間変動弾性曲線を近似した.
- 圧力値,シストリック時間間隔,およびストローク容量を用いて,単一ビートベースで推定Ees.
- 麻酔を受けた犬のカヴァル閉塞に対する方法を検証した.
主要な成果:
- シングルビートEes推定方法は,合理的な精度 (r=0.929) を示しました.
- この方法は,収縮性と負荷条件の大きな変化にもかかわらず,正確であり続けました.
- 傾斜比は収縮性と負荷の変化によって変化したが,Eesの推定は堅固であった.
結論:
- Eesは,シングルビートベースで信頼性のある見積もりをすることができます.
- 時間変動弾性曲線の二線関数近似は,正確なEes計算を可能にします.
- この方法は,簡単に得られる変数を用いて,Eesの評価を簡素化します.
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