海拔4520m健康人安静及运动负荷下的心功能  

CHANGES OF CARDIAC FUNCTION AT REST AND DURING EXERCISE IN HEALTHY RESIDENTS AT4 520M ALTITUDE

作　　者：吴天一 张丽珠 李万寿 

机构地区：[1]青海高原医学研究所

出　　处：《中国应用生理学杂志》1989年第2期147-153,共7页Chinese Journal of Applied Physiology

摘　　要：在海拔4 520m对健康世居藏族及移居汉族各15名,用心阻抗图测定了静息及逐级递增运动负荷后和恢复期的每搏量、心输出量及心缩间期(SV,CO及STI)。结果表明静息时SV、CO值两组均处于平原正常值的偏低水平,运动负荷后,移居组SV、CO于低、中强度负荷时增高,高强度负荷时反下降;世居组SV在低、中强负荷时上升,高强度负荷时恒定,CO随负荷增加呈持续上升且幅度大。最大氧耗量(VO_2max)值世居组为54ml/kg/min,移居组为44ml/kg/min(P<0.001)。运动负荷后STI出现与心泵功能相印证的变化,负荷开始之初两组PEP,LVET均缩短,PEP/LVET比值下降,但中强度负荷后,移居组PEP缩小不显且趋于稳定,LVET缩短,PEP/LVET比值出现回升;而世居组PEP、LVET逐级缩短,PEP/LVET比值逐级降低。SV、HR、CO、STI各值于运动后的恢复在世居组均较移居组为快。以上结果揭示,在低氧环境中,高原世居藏族比移居汉族的心储备更强,有更高的最大摄氧能力和负荷能力。Cardiac function was examined with electrical impedance at rest, during exercise and on recovery at altitude (4 520m). The experimental subjects were divided into two groups: 15 Tibetan natives(Tibetan group-TG) and 15 Han lowlanders who had lived at 4 520m for 1～2 years(Han group-HG). The results showed that (1) The values of SV and CO were slightly lower than the sea level values in both groups at rest. (2) during exercise, the SV, CO increased under lower(300-600kg.m/min) and moderate (900kg.m/min) work load and decrersed under submaximal (1 200kg.m / min) work load in the HG; the SV increased under lower and moderate work load, and tended to be stable under submaximal work load, HR, CO increased gradually with increased work load in the TG. (3) VO_2max were 54 ml/kg/min in TG and 44 ml / kg / min in HG (P < 0.001). (4)During exercise, PEP, LVET were shorter and PEP / LVET decrease under lower work load in both groups, but with increased work load, the PEP tended to be stable, the LVET shortened and the PEP/LVET increased in the HG; the PEP, LVET tended to shorten gradually and PEP/LVET showed a significant successive reduction in the TG. The recovery periods of SV, CO and STI after exercise were longer in the HG than in the TG. These results suggested that the native Tibetants adapted to hypoxic environment muchbetter than the lowlanders who had lived at altitude for 1-2years, because their cardiac reserve capacity and maximum oxygen uptake were better than those of lowlanders.

关 键 词：心输出量 心缩间期 运动 高原 

分 类 号：R339.54[医药卫生—人体生理学]