ペーシング誘発の慢性心房細動は,犬のシヌスノード機能を損なう. 電気生理学的な改造
1Krannert Institute of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, USA.
Circulation
|December 1, 1996
まとめ
ペースによって引き起こされる慢性心房細動 (AF) は,鼻腔節機能を損ない,伝導を遅らせます. 前頭房に対するこれらの悪影響は,AFが停止した後,徐々に逆転します.
科学分野:
- 心臓病学 心臓病学
- 電気生理学 電気生理学
- 心律不整症とは,心律不整症のこと.
背景:
- 慢性心房細動 (AF) は,心臓機能に著しく影響を与える可能性があります.
- 誘発されたAFの電気生理学的結果を理解することは,不律の管理に不可欠です.
研究 の 目的:
- シヌスノード機能に対するペース誘発性慢性心房細動 (AF) の影響を調査する.
- 慢性AFにおける心房内伝導と心房屈折性の変化を評価する.
- AF終了後のこれらの電気生理学的変化の可逆性を決定する.
主な方法:
- モンゴル犬はAVノードルブロックとVVIペースを施しました.
- 心房細動 (AF) は11匹の犬において,心房のペースを早めることで誘発された.
- シヌスノード回復時間,P波の持続時間,心拍数,心房有効耐火期 (ERP) を含む電気生理学的パラメータは,ベースラインおよびAF誘導後に測定されました.
主要な成果:
- 誘発された慢性AFは,修正されたシヌス節の回復時間とP波の持続時間を長引かせました.
- 最大心拍数と内在心拍数は低下し,心房ERPは短縮されました.
- AFの持続期間は著しく増加し,不律の持続を示唆しました.
- これらの変化は,シヌスリズムへの変換時に部分的な逆転を示しました.
結論:
- ペースによって引き起こされる慢性AFは,副鼻腔節機能不全と長時間の心房内伝導を引き起こします.
- 心房のリフレクター性は短縮され,AFの永続に寄与します.
- 慢性AFに関連した電気生理学的異常は,AF終了後に徐々に解消する.
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