機能ブロックの拡張が病変に関連した心房の作用
Y Tomita1, K Matsuo, J Sahadevan
1Department of Medicine, Division of Cardiology, Case Western Reserve University/University Hospitals of Cleveland, Cleveland, Ohio.
Circulation
|February 22, 2001
まとめ
右心房のブロックの位置は,心房動 (AFL) の再侵入回路の種類を決定する. この発見は,心臓手術後の慢性的なAFLを説明するのに役立ちます.
科学分野:
- 電気生理学 電気生理学
- 心臓の解剖学 心臓の解剖学
- アリズミーのメカニズム アリズミーのメカニズム
背景:
- venae cavae の間の右心房 (RA) のブロックラインは,古典的な心房 (AFL) に必要不可欠です.
- このブロックの正確な位置は,AFLのリエントラント回路タイプに影響を与える可能性があります.
研究 の 目的:
- RAにおけるブロックラインの位置が,AFL再入力回路のタイプを決定するという仮説を検証する (単回路対フィギュア・オブ・8).
主な方法:
- 13匹の犬の392箇所から同時に電気生理学的マッピングを行いました.
- 継続的なAFLの誘導は,RAフリー壁 (crista terminalisの前または後部) に線形的な病変を生成した後である.
主要な成果:
- 前頭部の病変を持つ4匹の犬では,AFLは病変の再侵入を伴う.
- 9匹の犬 (前部または後部損傷) で,AFLは前部RAフリー壁,心房隔膜,Bachmann's bundleの周りのシングルループ再入りを含む.
- どの犬にもフィギュア・オブ・8の再入力が誘発されませんでした.
結論:
- 固定ブロックの位置とその機能的な拡張が,AFLの再入国型を決定する.
- このメカニズムは,先天性心不全の手術後の患者の慢性AFLを説明する可能性がある.
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