バンドル・ブランチ・ブロックと陰性電気生理学検査の患者における昏睡のメカニズム
M Brignole1, C Menozzi, A Moya
1Departments of Cardiology, Ospedali Riuniti, Lavagna, Italy. mbrignole@ASL4.liguria.it
Circulation
|October 24, 2001
まとめ
バンドル・ブランチ・ブロック (BBB) と原因不明の昏睡の患者では,パラキシズマル・アトリオベンチキュラー (AV) ブロックによるアシストリック休止が長期間続くことが,再発性昏睡の主な原因である. この発見は,負の電気生理学的研究を持つ人でのメカニズムを明確にします.
科学分野:
- 心臓病学 心臓病学
- 電気生理学 電気生理学
- 内科内科は,内科の内科である.
背景:
- バンドル・ブランチ・ブロック (BBB) の患者における (syncope) は,往々にして心房内膜 (AV) ブロックに起因すると疑われる.
- 正確なメカニズムは不明であり,特に電気生理学的研究が否定的な結果を生むとき.
研究 の 目的:
- BBB患者および従来の診断検査で否定的な症状の患者における昏睡のメカニズムを調査する.
- この患者集団における再発性昏睡の原因を特定するために.
主な方法:
- 埋め込み式ループレコーダーは,BBBと原因不明のシンコペと診断された52人の患者に使用されました.
- 患者は3ヶ月から15ヶ月間,シンコパルの再発をモニターした.
主要な成果:
- 昏睡は42%の患者 (22人中52人) で再発し,19人の患者で事件が記録された.
- 最も一般的な発見は,主に心房静脈 (AV) ブロックによる長時間のアシストリック休止 (17人の患者) でした.
- ブラディカーディックエピソードは突然発症し,時には心室早拍が先行し,平均47秒の持続時間を有しました.
結論:
- BBB患者における再発性シンコペと,電気生理学的研究で否定的な結果は,しばしば共通のメカニズムを共有しています.
- このメカニズムは,長時間のアシストリック休止を伴うもので,主として突然発症したパラキシズマルの心房動脈 (AV) ブロックによって引き起こされます.
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