二相波形による除細動の強度-持続度および成功確率曲線
S A Feeser1, A S Tang, K M Kavanagh
1Department of Medicine, Duke University Medical Center, Durham, N.C. 27710.
Circulation
|December 1, 1990
まとめ
二相波形は,単相パルスよりもデフィブリレーションに有効です. この研究は,二相波形の有効性が傾きに依存していることを明らかにし,第2段階を超えて複数の除細動メカニズムを示唆しています.
科学分野:
- 心血管科学 心血管科学
- バイオメディカルエンジニアリング
- 電気工学 電気工学とは
背景:
- 双相波形は,単相パルスと比較してより高い有効性があるため,除細動のためにますます使用されています.
- 二相波形の効果を高める正確なメカニズムは,まだ完全に理解されていません.
- これらのメカニズムを理解することは,除細動戦略とデバイス設計の最適化に不可欠です.
研究 の 目的:
- 二相切断指数波形を用いた除細動のメカニズムを調査する.
- 単相パルスと二相パルスの除細動効率を,異なる持続時間と振幅で比較する.
- デフィブリレーションの成功における波形の傾きと第2相特性の役割を明らかにする.
主な方法:
- 単相波形と二相波形に対して,強度-持続時間および成功率の曲線が生成されました.
- 高低傾斜の二相波形と,相持続が異なる二相波形に対して,除細動の値が決定されました.
- 百分成功曲線は,二相波形の第2相の振幅を変更することによって構築されました.
主要な成果:
- 二相波形の除細動効率は,最初は改善され,その後は減少し,第2相の持続時間または振幅が増加するにつれて再び改善されます.
- >= 14 msec のパルスでは,高傾斜の二相波形の第2相値電圧は,同じ時間の単相パルスよりも高かった.
- 波形の傾きは,デフィブリレーションの有効性に大きく影響し,複雑な根本的なメカニズムを示唆しています.
結論:
- 双相除細動の効果は,心臓を刺激する第2相にのみ起因するものではありません.
- 少なくとも2つの異なるメカニズムが二相性除細動に寄与しています:一つは短い二相によって好まれ,もう一つはより長いまたはより高い振幅の二相によって好まれます.
- 二相波形における傾きの程度は,除細動の成功に影響を与える重要な要因である.
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