環状の形が小葉の曲線に与える影響は,小葉のミトラル・ストレスを軽減する
Ivan S Salgo1, Joseph H Gorman, Robert C Gorman
1Philips Medical Systems, Andover, Mass, USA. ivan_salgo@attbi.com
Circulation
|August 7, 2002
まとめ
ミトラアヌルスのサドル形は,フリレットストレスを軽減し,特にフリレット波が減少すると,フリレットストレスを軽減します. 哺乳類の間で保存されたこの形状は,心臓弁の機能のための重要な機械的利点を示唆しています.
科学分野:
- 心血管の力学 心血管の力学
- バイオメディカルエンジニアリング
- 心臓の解剖学 心臓の解剖学
背景:
- リーフレット曲線は,心臓弁の機械的ストレスを軽減するために重要です.
- ミトラアヌルスの形と小葉の波動は,小葉の曲線に大きく寄与する2つの要因です.
- 彼らの相対的な貢献を理解することは,心臓の健康に不可欠です.
研究 の 目的:
- リーフレットの波動とミトラルの環状の形がリーフレットの曲線に及ぼす独立と組み合わせた効果を調査する.
- 異なる環状幾何学の下,心臓弁の小冊子内のストレス分布を分析する.
- ミトラアヌルスの形によってもたらされる機械的利点を判断するために.
主な方法:
- 異なるミトラル環状ファントム (平らからサドル形) の数値シミュレーションを使用しました.
- 人間,羊,バビオンの3Dエコーカルディオグラフィとソノミクロメトリーの実験データを採用した.
- 環状の高さと状の幅の比率を用いて数値化された環状の形状.
主要な成果:
- ピーク・リーフレット・ストレスは,フラット・アヌリで最高であり,サドル形が大きくなるにつれて減少した.
- 最適なストレスの軽減は,指輪形の高さと指輪形の幅の比率15%から25%で発生しました.
- 哺乳類のアヌリ (人間,羊,バビオン) は,10%から15%の比率で類似した形状を示した.
結論:
- ミトラアヌルスのサドル形は,リーフレットの曲線を高めることで,重要な機械的利点を提供します.
- この利点は,環状の膨張による小葉の波の減少が曲線を損なう場合に特に重要です.
- 種間で保存されたの形は,進化上の利点を示唆し,ミトラル弁の義肢の設計に潜在的な応用がある.
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