冠内アミオダロン投与の薬理動力学および地域電気生理学的効果
Circulation
|January 15, 1995
まとめ
アミオダロン注入は,時間と濃度に依存した方法で,心筋伝導速度を遅らせました. これらの電気生理学的効果は,全身濃度ではなく,心筋アミオダロン濃度と相関していた.
科学分野:
- 薬理学 薬理学とは
- 心血管生理学 心血管の生理学
- 薬物電気生理学 薬物電気生理学
背景:
- アミオダロンの抗リズム効果と電気生理学的変化の遅れた発症は十分に理解されていません.
- アミオダロンの心筋度とその電気生理学的効果との関係は不明である.
研究 の 目的:
- 冠内輸液中のアミオダロンの電気生理学的効果の時間経過を調査する.
- これらの電気生理学的変化を心筋内アミオダロン濃度と相関させるため.
主な方法:
- 選択的冠内アミオダロン注入は,胸を開けた犬に10時間以上.
- 電気生理学研究 (EPS) と心筋組織の薬理学的サンプル採取 (PS)
- 薬に曝露した心筋と非曝露した心筋における伝導速度とアミオダロン濃度の測定.
主要な成果:
- 冠内アミオダロン注入は,心筋伝導速度 (縦横) の時間依存的な減少につながった.
- 伝導速度の変化は,心筋アミオダロン濃度 (R2 = .83) と有意に相関していた.
- アミオダロン濃度は,薬に曝された心筋に時間とともに有意に増加したが,暴露されていない心筋では低いままである.
結論:
- 選択的冠内アミオダロン注入は局所薬の蓄積を引き起こし,時間の経過とともに心筋伝導速度を低下させます.
- 心筋アミオダロン濃度,冠動脈または全身レベルではなく,導電速度の低下と相関しています.
- アミオダロンは,心筋リポラライゼーションを有意に変化させなかった.
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