高度暴露对冠状动脉流量储备的影响
Christophe A Wyss1, Pascal Koepfli, Gregory Fretz
1Department of Cardiology, University Hospital, Zurich, Switzerland.
Circulation
|August 27, 2003
概括
患有冠状动脉疾病 (CAD) 的患者在2500米的海拔上经历了减少的炼储备. 健康的个体保持储备高达4500米,建议对中等高度的CAD患者保持谨慎.
科学领域:
- 心脏病学 心脏病学
- 高度生理学 高度生理学
- 心血管研究研究心血管研究
背景情况:
- 关于高度暴露对冠状动脉流量储备 (CFR) 的影响的数据有限.
- 建议冠状动脉疾病 (CAD) 患者避免在2500米以上的高度.
- 这项研究研究了高度对健康个体和CAD患者心肌动脉血流 (MBF) 的影响.
研究的目的:
- 评估不同高度对心肌动脉血流 (MBF) 和冠状动脉流量储备 (CFR) 的影响.
- 为了比较健康对照组与冠状动脉疾病 (CAD) 患者对高度的生理反应.
主要方法:
- 用15O标记水的正子发射断层扫描 (PET) 用于测量休息和压力 (腺和运动) 期间的MBF.
- 测量是在normoxia和模拟高度 (对照组4500米,CAD患者2500米) 进行.
- 调整了工作量,以保持可比的心率-血压产品在正常和缺氧条件下.
主要成果:
- 在4500m (+24%) 的对照组和在2500m (+24%) 的CAD患者中,休息的MBF显著增加.
- 在任何一组中,腺素诱导的高血压和CFR都不受高度的影响.
- 运动引起的高血压在4500米的对照人群中增加,但在2500米的CAD患者中减少,导致对照人群中保持运动储备和CAD患者中减少储备.
结论:
- 在海拔2500米处,CAD患者的运动诱导储备显著下降.
- 即使在中等高度,CAD患者的补偿机制也可能受到损害.
- 患有CAD和CFR受损的患者应在中等高度的体力活动中谨慎行事.
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