ヒトの心房動および動中のプロカイナミドと比較して,静脈注入イブチリドの抗リズム作用: 強化された変換有効性の電気生理学的決定因子
B S Stambler1, M A Wood, K A Ellenbogen
1West Roxbury Veterans Affairs Medical Center and Harvard Medical School, Mass 02132, USA.
Circulation
|January 7, 1998
まとめ
イブチリドは,アクションポテンシャル期間を長引かせて,プロカイナミドを上回り,心房振動 (AFL) と心房細動 (AF) を効果的に変換します. 終了メカニズムは,特にAFLでは,心房循環の長さとアクションポテンシャルの持続時間における変動性の増加を伴う.
科学分野:
- 電気生理学 電気生理学
- 心臓病学 心臓病学
- 薬理学 薬理学とは
背景:
- 抗リズム剤のイブチリドは,アクションポテンシャル期間を長引かせることで,心房振動 (AFL) と心房細動 (AF) を終了させます.
- ヒトにおけるイブチリドの有効性の正確なメカニズムについては,さらなる特徴づけが必要である.
- この研究では,イブチリドの効果とプロカナミドの効果をAFLとAFで比較しています.
研究 の 目的:
- ヒトにおけるイブチリドとプロカインアミドの抗リズム効果をAFLとAFと比較するために.
- AFLとAFの薬理学的終結を促進する電気生理学的特性を調査する.
主な方法:
- AFLまたはAF中の136人の患者で記録された右心房単相アクションポテンシャル.
- 静脈内投与されたイブチリド,プロカイナミド,またはプラセボ.
- アクションポテンシャル持続時間 (MAPD) やサイクル長さ (CL) などの変換率と電気生理学的パラメータを分析した.
主要な成果:
- イブチリドは,プロカナミド (AFLの0%,AFの5%) とプラセボ (両方とも0%) と比較して,AFL (64%) とAF (32%) に対してより高い変換率を示しました.
- イブチリドは,AFLにおけるプロカイナミドよりも心房MAPDを増加させ,プロカイナミドは,アクションポテンシャルダイアストリック間隔を延長した.
- AFにおけるイブチリドの有効性は,より長いベースライン心房CL (> 160 ms) またはMAPD (> 125 ms) と相関していました.
結論:
- AFLの変換におけるイブチリドの優れた有効性は,CLと比較してより大きなMAPD延長に関連しています.
- イブチリドによるAFL終結には,心房CLとMAPDの振動が含まれています.
- ベースラインの心房CLとMAPDは,イブチリドのAFの転換における成功を予測しています.
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