亜急性心筋梗塞における再侵入性心室リズムに対するアドレネルジック効果
G S Butrous1, W B Gough, M Restivo
1Department of Medicine, State University of New York Health Science Center, Brooklyn.
Circulation
|July 1, 1992
まとめ
交感刺激は,心臓発作後の心室不律を誘発し,再入りを促すことができる. しかし,ノレピネフリン注入は,損傷した心臓の電気的性質を変更することによって,これらの不律を軽減することができます.
科学分野:
- 心臓病学 心臓病学
- 電気生理学 電気生理学
- 心臓病理生理学 心臓病理生理学
背景:
- リエントリーは,心筋梗塞後の心房不律症の重要なメカニズムです.
- 空間的折射性は,プログラムされた刺激中に導電ブロックに影響します.
- 心筋梗塞は,心臓の交感性内置に影響し,不律に影響を与えます.
研究 の 目的:
- 犬の心筋梗塞の4日後の再侵入媒介性心室不律症における交感神経系の役割を調査する.
- アドレナージック刺激が,心筋不全および正常な心臓組織における伝導性と折射性にどのように影響するかを理解する.
主な方法:
- 心筋梗塞の4日後の犬に128チャンネルコンピュータ化された記録システムを使用した.
- アンセ・サブクラビアの双方向刺激と静脈内注入のノレピネフリンを施した.
- 測定された興奮性の変化と,イシュケミックゾーンと正常ゾーンの有効な耐火期.
主要な成果:
- 交感刺激は正常なゾーンでの伝導性を改善し,そこで耐火期を短縮したが,不血性ゾーンではそうではなかった.
- ノルエピネフリン注入は,イシュケミックゾーンにおける耐火期を好ましく短縮し,デナーベーション過敏症を示唆した.
- 両方の介入は,屈折性の空間的分散と機能的伝導ブロックの弧のサイズを減少させた.
- 以前は誘導可能だったリエントラントリズムが非誘導的になった.
結論:
- 交感刺激は,このモデルではリズムを誘発する介入として作用します.
- ノルエピネフリン注入は,発作後の再侵入の文脈で抗不律性潜在能力を示しています.
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