電気的異質性の誘導は,心室除細動を損なう:地域的な伝導速度を遅らせることに特異的な効果
M R Ujhelyi1, J J Sims, A W Miller
1University of Georgia College of Pharmacy, Augusta VA Medical Center, and Medical College of Georgia School of Medicine, Augusta, USA. michael.ujhelyi@medtronic.com
Circulation
|December 22, 1999
まとめ
導電速度における分散は,反射性ではなく,除細動エネルギー要件 (DERs) を増加させる. リドカインは伝導を遅くし,DERを増加させ,d-sotalolはDERを変化させずに屈折性を影響し,伝導速度分散がデフィブリレーションの有効性の鍵であることを示唆しています.
科学分野:
- 心血管生理学 心血管の生理学
- 電気生理学 電気生理学
- 医療機器工学 医療機器工学とは
背景:
- デフィブリレーションエネルギー要求 (DER) は,正常な心拍の回復に不可欠です.
- DERに影響を与える要因は,電気伝導性や反射性など,完全に理解されていません.
- これらの要因を理解することで, défibrillation 戦略を最適化することができます.
研究 の 目的:
- 導電速度,屈折性,興奮性の変化が二相ショック除細動エネルギー要件 (DERs) に与える影響を調査する.
- これらの電気特性における分散が DERs に影響するかどうかを判断する.
- デフィブリレーションの有効性の基礎となるメカニズムを解明する.
主な方法:
- 24匹の豚は,リドカイン,d-ソタロール (低用量および高用量),または塩水による地域性心筋内注入を受けた.
- 効果的な耐火期 (ERP) と伝導速度を複数の心筋部位で測定した.
- デフィブリレーションエネルギー要求 (DERs) と心房細動 (VF) パラメータを評価した.
主要な成果:
- 地域のリドカイン注入は,DERを84%増加させ,伝導速度を23-35%減速させ,伝導速度分散を増加させました.
- 地域的なd-sotalolはERPを14-17%増加させ,ERP分散を140%増加させましたが,DERや伝導速度には影響しませんでした.
- リドカインはほとんどの動物で心房細動 (VF) を誘導したが,d-sotalolは誘導しなかった.両剤はVFのサイクル長さを延長し,その分散を増加させた.
結論:
- 地域伝導速度の減速とその分散は,DERsを著しく増加させる.
- 導電速度を変えることなく,屈折性の分散が増加しても,DERsには影響はありません.
- 導電速度の分散は,屈折率の分散よりも,除細動の有効性の決定的な決定因子であるようです.
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