室内タキアリズム症の予測因子としてのマイクロボルトT波変数: atrial pacingを用いた将来性研究
Kaoru Tanno1, Syunsho Ryu, Norikazu Watanabe
1Third Department of Internal Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan. k-tanno@p02.itscom.ne
Circulation
|April 7, 2004
まとめ
心拍数が低いマイクロボルトのT波代替 (TWA) 患者では,心室性タキアリズム症のリスクが高くなります. この発見は,突然の心臓死のリスクに対するTWAの評価における心拍数の重要性を強調しています.
科学分野:
- 心臓病学 心臓病学
- 電気生理学 電気生理学
- 心臓発作に関する研究
背景:
- マイクロボルトのT波変数 (TWA) は,急性心臓死 (SCD) と心室性短拍 (VT) の認識されたマーカーです.
- 以前の研究は,TWAの表れと心拍数との間に有意な相関関係があることを示しています.
- 心拍数によるTWAの心室性タキアリズム症の予測値への影響については,さらなる調査が必要である.
研究 の 目的:
- 低心拍で検出されたTWAと心室性タキアリズム症のリスクとの関係を調査する.
- 心拍数が低下した状態でTWAを呈している患者が,生命を脅かす不律症により脆弱であるかどうかを判断する.
主な方法:
- 1997年から2000年の間に248人の患者を対象に電気生理学的研究が行われました.
- TWAは,シヌスリズムと心房ペースで1分90回,100回,110回,120回のペースで記録されました.
- 代替電圧 (V(alt)) を測定し,患者さんにはVT,VF,SCD,または適切なインプラント可能な心変容器-除細動器療法について追跡しました.
主要な成果:
- VT/VF/SCDの発生率が高かったのは,90 , 100 , 110 bpm (それぞれ56%,28%,18%) でV{alt) >1.9 microVの患者で観察された.
- 90bpmで>2.9マイクロVのV{\alt}は,VT/VF/SCD.の70%のポジティブな予測値を示しました.
- 120bpmで0.9microV未満のAVは100%の負の予測値を示し,より高い心拍数での安全性を示唆しました.
結論:
- 比較的低い心拍で検出されたTWAの患者は,心室性タキアリズム症に対する感受性が高まっている.
- 心拍数は,TWAの解釈において,突然の心臓死のリスク層分化の重要な要因である.
- これらの発見は,不律症のリスクに対するTWAを評価する際に心拍数を考慮することの重要性を強調しています.
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