固定された障害物の周りのリエントラント刺激は,均一なアニゾトロプ的心室性心筋膜に均一にアニゾトロプ的心室性心筋膜に存在する
J Brugada1, L Boersma, C J Kirchhof
1Department of Physiology, University of Limburg, Maastricht, The Netherlands.
Circulation
|September 1, 1991
まとめ
組織アニソトロピーと早急な鼓動は,均一な心筋組織で繊維の方向に平行な伝導ブロックを引き起こすことによって,再侵入性心室低心率 (VT) を開始します. この発見は,VT開始メカニズムを明確にします.
科学分野:
- 心血管生理学 心血管の生理学
- 電気生理学 電気生理学
- 心律不整症とは,心律不整症のこと.
背景:
- リエントラント心室性短拍 (VT) は,生命を脅かす不律性です.
- VT開始の理解は,効果的な治療法の開発に不可欠です.
- 組織アニソトロピーと屈折性の分散は,VTの病原性に関与しています.
研究 の 目的:
- 組織アニソトロピーの作用を調査し,再侵入性心室性タヒカルディア (VT) を開始する.
- VT開始に対する屈折性の分散の影響を調べる.
- 均一なアニゾトロプ的心筋に再侵入性VTを潜むメカニズムを解明する.
主な方法:
- Langendorff-perfusedウサギの心臓で内臓凍結技術を使用して,均一なアニゾトロピック室内膜の環を作成しました.
- 高解像度マッピング (248チャンネル) を利用して,上心部活性化パターンを分析した.
- リエントラントVT開始を評価するために,複数のポイントで早発の鼓動を誘発.
主要な成果:
- リエントラントVTは,272のテストポイントのうち43で開始されました.
- 導電速度は,繊維の方向性に対して平行 (60cm/sec) と垂直 (25cm/sec) よりも著しく高かった.
- 片方向の伝導ブロックは,主に光ファイバーの指向に並行して発生した (41/43例).
- 断裂性の分散はブロック形成 (12/43例) に起因する小さな役割を果たした.
結論:
- 均一なアニソトロプ的心筋筋では,再侵入性VTは早発のビートによって開始されます.
- 早期ビートの刺激効果が低下すると,繊維の指向に並行して優先伝導ブロックが形成されます.
- この優遇ブロックは,このモデルにおける再入国者VT開始の主なメカニズムです.
さらに関連する動画
関連する概念動画
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01:30Cardiac Action Potential
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Ionic Basis of Cardiac Action Potentials
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