標高曝露が冠動脈の流れ準備量に及ぼす影響
Christophe A Wyss1, Pascal Koepfli, Gregory Fretz
1Department of Cardiology, University Hospital, Zurich, Switzerland.
Circulation
|August 27, 2003
まとめ
冠動脈疾患 (CAD) の患者は,標高2500mでの運動の準備が低下した経験があります. 健康な個人は4500mまで予備を維持し,中程度の高度でのCAD患者の注意を促します.
科学分野:
- 心臓病学 心臓病学
- 高度生理学 高度生理学
- 心血管科学の研究について
背景:
- 冠動脈フロー・リザーブ (CFR) に対する高度曝露の影響に関するデータは限られている.
- 冠動脈疾患 (CAD) の患者は,2500m以上の高度を避けることをお勧めします.
- この研究は,健康な個人およびCAD患者における心筋動脈血流 (MBF) に対する高度の影響を調査しています.
研究 の 目的:
- 心筋血流 (MBF) と冠動脈血流準備量 (CFR) に対する高度の変動の影響を評価する.
- 健康な対照群の高度に対する生理学的反応を,冠動脈疾患 (CAD) の患者と比較するために.
主な方法:
- 15Oラベル付き水によるポジトロン放出トモグラフィー (PET) は,休息状態およびストレス (アデノシンおよび運動) 時のMBFを測定するために使用されます.
- 測定はノルモキシアとシミュレートされた高度 (対照群では4500m,CAD患者では2500m) で行われました.
- 労働負荷は,ノルモキシカル条件とヒポキシカル条件の両方で,比較可能な心拍数-血圧製品を維持するために調整されました.
主要な成果:
- 休息時のMBFは,4500m (+24%) のコントロール群で,2500m (+24%) のCAD患者で有意に増加しました.
- アデノシン誘発性高血症とCFRは,どちらのグループでも高度の影響を受けなかった.
- 運動誘発性高血圧は,対照群では4500mで増加したが,CAD患者では2500mで減少し,対照群では運動予備が維持され,CAD患者では予備が減少した.
結論:
- CADの患者は,標高2500mでの運動誘発予備の有意な減少を示しています.
- CAD患者の補償メカニズムは,適度な高度でも損なわれることがあります.
- CADおよびCFR障害の患者は,適度な高度での身体活動中に注意を払う必要があります.
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