クラスIの抗不律薬によって引き起こされる伝導の減速に対する再偏振後の反射性:抗不律および前不律効果
P F Kirchhof1, C L Fabritz, M R Franz
1Cardiology Division, Veterans National Administration Center, Washington, DC 20422, USA.
Circulation
|July 10, 1998
まとめ
薬剤誘発後の反偏断性 (PRR) は,心房細動 (VF) に対して保護します. しかし,プロパフェノンは,伝導と波長に影響することで,遅いモノモルフ的心室性短拍 (VT) を促進することができます.
科学分野:
- 電気生理学 電気生理学
- 心臓薬理学 心臓薬理学
背景:
- 導電ブロックは,抗不律性および前不律性の両方であり得る.
- 薬剤誘発後の反偏光性 (PRR) はタキアリズムを予防する可能性があります.
- プロパフェノンとプロカイナミドの抗不律性および前不律性効果が調査されました.
研究 の 目的:
- プロパフェノンとプロカイナミドが心臓の電気生理学に及ぼす影響を調査する.
- これらの薬剤の抗不律性または前不律性影響を決定する.
- 薬剤誘発性心律不整症におけるポストレポラライゼーション屈折性の役割を評価する.
主な方法:
- 孤立したランゲンドルフ浸透したウサギの心臓を使用した.
- モノフェーシックアクションポテンシャル (MAP) とEKGを記録した.
- 静脈動脈短拍 (VT) と動 (VF) は,薬剤投与前後の電気刺激によって誘発された.
主要な成果:
- プロパフェノンとプロカイナミドの両方が,アクションポテンシャル期間を延長し,PRRを誘発しました.
- プロカイナミドはVF誘導性を70%低下させ,プロパフェノンはVFを排除した.
- プロパフェノンは伝導を著しく遅らせ,波長を短くし,バースト刺激の57%で静脈伝導誘導につながった.
結論:
- 薬剤誘発PRRは,心房細動 (VF) に対して効果的に保護します.
- プロパフェノンは,VFを予防するにもかかわらず,遅いモノモルフのVTを促進することができます.
- プロパフェノンによる使用依存伝導の減速と波長の短縮は,おそらくVT促進の基礎となっている.
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