静脈動中の心経ショック後の耐火間
R J Sweeney1, R M Gill, P R Reid
1Department of Electrophysiology Research, Eli Lilly and Co, Indianapolis, Ind, USA. sweeneyrj@sjm.com
Circulation
|December 1, 1996
まとめ
デフィブリレーションショックは,心臓に短い耐火期を作り出し,ショック後すぐに再フィブリレーションを防ぐ. このショック後耐火間隔は,単相ショックよりも二相ショックで短くなります.
科学分野:
- 心臓病学 心臓病学
- 電気生理学 電気生理学
- 医療機器 医療機器について
背景:
- 快速な心房のペースは,除細動ショック後の耐火期を示唆する.
- フィブリレーション中のショック後の耐火間間の実験的検証が必要でした.
研究 の 目的:
- 室細動中の除細動ショック直後に耐火間が存在するかどうかを判断する.
- モノフェーシック・ショックとバイフェーシック・ショックの衝撃後耐火性インターバル期間を比較する.
主な方法:
- 麻酔を受けた犬は,単相または二相ショックを受け,その後,ショック後の刺激 (PSS) を受けました.
- 50%のデフィブリレーションの成功率に対する衝撃電流 (I50) を測定した.
- ショックに対するPSSのタイミングは様々でした.
主要な成果:
- 1.0-A PSSは,単相ショック後に50〜90 msを投与すると,I50を大幅に増加させた.
- 1.0-A PSSは,二相性ショック後のI50も増加したが,一相性ショック後のより大きな程度であった.
- 0.5-A PSSは,どのテストタイミングでもI50に影響を与えませんでした.
結論:
- 震動後の耐震間隔は,動中の単相および二相のショックの両方後に存在します.
- この耐火間隔は,単相ショックと比較して,二相ショックでは短くなります.
- 発見は,除細動のための耐火期延長仮説を裏付けている.
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