QT分散の自動測定における鉛選択と集団の影響
P W Macfarlane1, S C McLaughlin, J C Rodger
1University of Glasgow (P.W.M., Glasgow, Scotland. peter.w.macfarlane@clinmed.gla.ac.uk
Circulation
|November 17, 1998
まとめ
QT分散 (QTd) は,健康な個体では年齢と性別にかかわらず,正常値上限は50 msである.QTdは,心筋梗塞後の患者で高く,ECGリードタイプによって異なります.
科学分野:
- 心臓病学 心臓病学
- エレクトロカーディオグラフィーです.
- 臨床的な測定 臨床的な測定
背景:
- QT分散 (QTd) は,臨床的に関心が高まっている.
- 大規模で健康な集団に関するデータは限られている.
- QTdと測定の変動性の関係については,説明が必要である.
研究 の 目的:
- 大規模で健康な集団で正常なQTd限界を確立する.
- QTdを年齢,性別,心電図のリード構成に関連して調査する.
- 前回の心筋梗塞を有する患者のQTdを評価する.
主な方法:
- 自動化された方法を使用して,1501人の健康な成人と1784人の子供の12鉛のECGを分析しました.
- 3対のリードECG (n=1220) から12リードECGを導出しました.
- 比較されたQTdは,正常な被験者と,前回の心筋梗塞を患った361人の患者を比較した.
主要な成果:
- 年齢や性別に関係なく,正常QTd上限50msを確立しました.
- オートゴナルリードから12リードのECGを導いたとき,QTdの有意な増加が観察されました.
- 健康な成人と比較して,前回の心筋梗塞を有する患者のQTdが有意に高かった.
結論:
- QTdは,年齢と性別にかかわらず,信頼性の高いマーカーであり,通常の上限は50ミリ秒です.
- ECGのリード構成は,QTd測定に影響します.
- QTdの上昇は,前回の心筋梗塞と関連しています.
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