タイプ5の長QT症候群の国際的多センター評価:低浸透性一次不律症
Jason D Roberts1, S Yukiko Asaki2, Andrea Mazzanti3,4
1Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Western University, London, Ontario, Canada (J.D.R., I.E.H., M.D.Y., L.J.G., P.L.-S.).
Circulation
|January 17, 2020
まとめ
長QT症候群5型 (LQT5) に関連した稀なKCNE1変異は,低ECG浸透率を示し,これらの変異を持つほとんどの個人は臨床症状を発症しません. これは,KCNE1変異がQT延長を誘発するが,必ずしもLQT5疾患を誘発することはないことを示唆している.
科学分野:
- 心血管遺伝学
- イオンチャネル病
- 電気生理学
背景:
- 長いQT症候群5型 (LQT5) の臨床的および遺伝的特徴の理解は限られている.
- 以前の洞察は主に症例報告と小さな家族研究から得られた.
- LQT5における稀なKCNE1変異の包括的な分析の必要性
研究 の 目的:
- LQT5における希少なKCNE1変異の臨床表型と遺伝的特徴を調査する.
- LQT5におけるECGの浸透率と遺伝子型-フェノタイプの相関性を評価する.
- LQT5プロバンドと家族間の不律の発生リスクを比較する.
主な方法:
- 229人のLQT5および19人のJervellおよびLange- Nielsen症候群の患者を含む国際的多中心共同研究.
- 32の異なるKCNE1変異のEKG浸透性と分離の評価
- アリズム障害のリスク評価のための多変量コックス回帰分析
主要な成果:
- 89人のLQT5プロバンドと140人のファミリーメンバーで32種類のKCNE1を特定した.
- LQT5ファミリーのヘテロジゴスは,ECGの穿透率20. 7% (QTc>460 ms) を示した.
- LQT5試験参加者は,家族に比べて心律乱発症のリスクが著しく高かった (aHR 11. 6).
結論:
- KCNE1変異の機能喪失はQT延長を誘発する.
- 低ECG浸透度は,変異が臨床的に表れないことを示す.
- 2型JervellおよびLange- Nielsen症候群の患者で観察されたより軽いフェノタイプと一致しています.
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