PRインターバルが長引いた個体または1度目の心房静脈閉塞を有する個体における長期的なアウトカム
Susan Cheng1, Michelle J Keyes, Martin G Larson
1Framingham Heart Study, Framingham, Massachusetts, USA.
JAMA
|June 25, 2009
まとめ
1度目の心房動脈閉塞の兆候であるPRインターバルが長引くことは,心房細動 (AF),ペースメーカーインプラント,および出院患者における全原因死亡率のリスクを大幅に増加させます.
科学分野:
- 心臓病学 心臓病学
- 電気生理学 電気生理学
- 予防医学は,予防的な医療です.
背景:
- 200ミリ秒を超えるPR間隔で定義される第一度の心房閉塞は,一般的な心電図の発見です.
- 無症状の個体におけるPR延長の臨床的意義については,さらなる解明が必要である.
研究 の 目的:
- コミュニティベースのコホートにおけるPR間隔延長の長期的な臨床的影響を調査する.
- PR延長と心房細動,ペースメーカーインプラント,全原因死亡率との関連性を評価する.
主な方法:
- フレミングハム心臓研究から7575人の個人を対象とした将来性のあるコミュニティベースのコホート研究.
- ベースライン12リード心電図とPR間隔評価.
- 2007年までのフォローアップは,多変数調整のコックス比例リスクモデルを用いて行われます.
主要な成果:
- PR間隔>200msの個人は,心房細動 (AF),ペースメーカーインプラント,全原因死亡率の有意に高い発生率を示しました.
- PR間隔の20msの増加ごとに,AF,ペースメーカーインプラント,全原因死亡率の調整された危険比率が増加しました.
- 第1度の心房静脈閉塞は,調整したAFのリスクの2倍,ペースメーカーインプラントのリスクの3倍,全原因死亡のリスクの1.4倍を伴う.
結論:
- PR間隔の延長は,有害な心血管疾患の結果の有意な独立した予測因子です.
- PR間隔が長い個人を特定することは,リスクの階層化と予防戦略に役立ちます.
- この発見は,通常の臨床実務における心電図評価の重要性を強調しています.
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