大型心臓発作の余った上心部への高電流の刺激は,心室動脈性タヒカルディアを誘発する
K M Kavanagh1, J S Kabas, D L Rollins
1Department of Medicine, Duke University Medical Center, Durham, NC 27710.
Circulation
|February 1, 1992
まとめ
この研究は,特定の電気刺激プロトコルが,フィギュア8の再侵入経路を作り出すことによって,心室低血圧 (VT) または心室細動 (VF) を誘導できることを示しています. 組織の種類と周期の長さは,VTまたはVFが起こるか否かを決定し,不律を研究するための新しい方法を提供します.
科学分野:
- 心血管電気生理学 心血管電気生理学
- 心臓発作に関する研究
- 心筋梗塞のモデル
背景:
- Ventricular tachycardia (VT) と ventricular fibrillation (VF) は,フィギュア8の再入場経路から発生することがあります.
- アリズム障害のタイプ (VT vs. VF) は,誘導法だけでなく,組織特性とサイクル長さに依存します.
- 以前の研究では,特定の刺激プロトコルが心拍不全の結果に影響を及ぼす可能性があることが示唆されています.
研究 の 目的:
- 心筋梗塞の値決定に使用されるプロトコルが,心臓発作で保存された心筋組織にVTを誘導できるかどうかを調査する.
- 刺激パラメータ,組織特性,および持続的なモノモルフィックVTとVFの誘導の間の関係を調査する.
- VT研究のための既知のフィギュア8の再入国経路を誘導するための再現可能な方法を確立する.
主な方法:
- 心筋梗塞の犬のモデル (左前垂動冠動脈閉塞-再注血) を利用しました.
- さまざまな心室部部位からS1刺激を送り,その後,心臓発作の表面にS2刺激を送った.
- 体系的にS2刺激の強度と,減速するサイクル長度でダイアストリックカップリングの間隔を変化させ,不律を誘発する.
主要な成果:
- 持続的なモノモルフィックフィギュア8型VTは,VF (9種) よりも (24種) より頻繁に誘発された (p=0.03).
- VTは,VF (115 ± 13 msec) (p<0.001) と比較して,より長い平均サイクルの長さ (152 ± 33 msec) を示した.
- 心臓発作のトランスムラル範囲は,不律症のアウトカントと相関しており,より薄い心臓発作は静脈経路誘導を好む.
結論:
- 非トランスムラー性心臓発作に施された大きなS2刺激は,保存された心筋が薄い場合,信頼性の高いVTを誘導することができます.
- この研究は,予測可能なフィギュア8経路方向性を持つ持続的なモノモルフVTを誘導するための新しいテクニックを提示しています.
- この方法は,刺激パラメータとS1サイトを調整することによって,様々なVT形態の制御された誘導を可能にします.
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