人間の心室における活性化と再偏極化のグローバルダイナミックカップリング
Arthur M Yue1, Tim R Betts, Paul R Roberts
1Wessex Cardiac Center, Southampton General Hospital, Southampton SO16 6YD, UK.
Circulation
|October 26, 2005
まとめ
ノンコンタクトマッピングは,心室再偏極化ダイナミクスを評価することができます. この研究は,活性化と再極化との間の逆結合を示し,健康な心室の電気的安定性を潜在的に保ちます.
科学分野:
- 心血管電気生理学 心血管電気生理学
- 心臓マッピングです.
- 静脈動力学 静脈動力学 静脈動力学
背景:
- 静脈の再偏極化変化を理解することは,心拍不良を引き起こすメカニズムを特定するために極めて重要です.
- ノンコンタクトマッピングは,ヒトの心室内のグローバル活性化-再偏極化結合を研究するための潜在的な方法を提供します.
研究 の 目的:
- 非接触マッピングを用いて,ヒトの心室におけるグローバル活性化-再偏極化結合を分析する可能性を調査する.
- 安定状態と早めの刺激を含む様々な電気生理学的条件下で,この結合を検査する.
主な方法:
- 活性化-回復間隔 (ARI) は,構造的な心臓病のない13人の患者で,エンサイトシステムを使用して,心室ごとに32箇所で測定されました.
- この方法は,単相アクションポテンシャル記録と単極コンタクト電図に対して検証されました.
- グローバルT波分布は3D心室モデルで可視化されました.
主要な成果:
- シヌスリズム,心室内外症,早めの刺激 (r=0.72,P<0.001) 時の活性化時間とARIの間に有意な逆相関が認められた.
- 短い結合間隔での早発刺激は,回帰の傾きを変えたが,グローバル再極化パターンを保持した.
- EnsiteシステムのARI測定は,ワイアット法 (r=0.34) と異なり,有意なカップリングを示した.
結論:
- 人間の心室のグローバル・ダイナミック・リポラライゼーション・マッピングは,非接触マッピングを用いて実現可能である.
- 安定状態と早めの刺激の間での活性化と再極化間の逆結合は,正常な心室における電気的安定性の維持に寄与する可能性があります.
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