心率变异性各频域能量的药理学评价

目的:探讨药物部分阻断交感神经、迷走神经后心率变异各频域能量的变化,以推证本文采用的心率变异频域分析方法.方法:6例健康志愿者静脉注射美托洛尔5mg,6例健康志愿者静脉注射阿托品2mg,采集用药前30min以及用药后30min、60min、90min、120min的心电信号,采用重庆大学电气工程学院设计的心率变异计算机分析软件分析心率变异的时域和频域指标(高频、低频、极低频、超低频),分析其用药前后的动态变化.结果:静脉注射美托洛尔后,SDNN,rMSSD,及pNN50均增加,HRV三角指数下降.高频频谱在总功率谱中相对值由用药前的34.45%增加到用药30min的50.03%(P＜0.05),超低频频谱相对值由11.79%减小到4.45%(P＜0.05).注射阿托品后,SDNN、rMSSD、pNN50显著减小,HRV三角指数增大.高频频谱在总功率谱中相对值在用药后30min由34.45%减少到4.32%(P＜0.05),超低频频谱相对值增加到80.27%(P＜0.05).随时间延长,各频段能量逐渐恢复.结论:本文结果提示采用该心率变异计算机分析软件所得超低频频谱可以较好地反映纯交感神经活性的作用.

Pharmacological evaluation on the different frequency domain of heart rate variability

Objective:To observe the changes of the different frequency domain of heart rate variability after the partial block of the sympathetic and vagal activity and to prove the correctness of the analysis system.Methods:Six healthy volunteers were injected intravenously with metoprolol (5mg )and six with atropine (2mg).The heart electronic signals were collected 30 minutes before the injection and 30 minutes after the injection.The collection and analysis system were provided by the electrodynamic engineering college of the Chongqing University.The values of the HF,LF,VLF and ULF were assayed and the changes between two drugs and among the different time were compared.The time domain was calculated as well.Results:SDNN,rMSSD and pNN50 were increased while HRV triangle value was decreased after the injection of metoprolol.The comparative value of the HF increased from 34.45% to 50.03%(p<0.05)while the ULF decreased from 11.79% to 4.45%(P<0.05)in the first 30 minutes period after the injection of metoprolol.SDNN,rMSSD and pNN50 were decreased while HRV triangle value was increased after the injection of atropine.The comparative value of the HF was down to 4.32%(P<0.05)while the ULF was up to 80.27%(P<0.05)in the first 30 minutes period after the injection of atropine.The energy at the respective frequency spectrum was renewed as the time passed.Conclusion:ULF can reflect the relatively pure sympathetic activity in this HRV analysis system.