室細動除細動中の単発的,結合的,連続的なショックによって生成される心臓ポテンシャルおよびポテンシャルグラデントフィールド.
J M Wharton1, P D Wolf, W M Smith
1Department of Medicine, Duke University Medical Center, Durham, N.C. 27710.
Circulation
|April 1, 1992
まとめ
デフィブリレーションショックの有効性を理解するには,潜在的なグラデントフィールドを分析する必要があります. この研究は,最小グラデントが一貫している一方で,不均等なフィールドは,除細動障害や不律を招き,除細動の値電流に影響を及ぼすことを明らかにしています.
科学分野:
- 心血管の生理学 心血管の生理学
- バイオメディカルエンジニアリング
- 電気生理学 電気生理学
背景:
- 潜在的なグラデントフィールドの決定は,除細動のショック効果を理解するために重要です.
- 様々な電極構成を用いた défibrillation の確立された要件は欠けている.
研究 の 目的:
- デフィブリレーションのための潜在的なグラデントフィールドの要件を評価する.
- 異なる電極構成がデフィブリレーションの有効性に与える影響を評価する.
主な方法:
- デフィブリレーションショック中に12匹のオープンチェスト犬の74個のエピカーディアル電極を使用して潜在的なフィールドを記録しました.
- 4つの電極構成をテストした:R:V,L:V, (R+L):V,および連続的なR:V----L:Vショック.
- 測定された除細動値 (DFT) の電流と最小ポテンシャルグラデーション.
主要な成果:
- 連続的なR:V----L:V構成では,DFTの電流が著しく低下した.
- DFTでの最小ポテンシャルグラデーションは,構成全体で類似していました (約. 6~7V/cm) となっている.
- 潜在的グラデントフィールドは不均一で (15〜27倍の変化),特定の領域では弱いフィールドがあり,失敗したショック後の活性化部位と相関していました.
結論:
- 小さな心帯電極からの除細動場は,非常に不均一です.
- 両心室の間の最小のポテンシャル・グラデントは,除細動に不可欠である.
- このグラデントを達成するために必要な衝撃強さの変動は,構成間のDFTの違いを説明します.
- 高いグラデントの領域は,ショック後の子宮外活性化を誘導する可能性があります.
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