窦性心动过速对心率变异的影响

目的 进一步认识心率变异,探讨心脏自主神经系统功能.方法 对58例心电图诊断正常者与心电图诊断窦性心动过速患者进行24h动态心电图观察,检测出最快心率、最慢心率、平均心率,再采用时域法、频域法进行心率变异分析,了解自主神经系统对窦房结的支配有无改变.结果 心电图诊断正常组与心电图诊断窦性心动过速组相比较,窦性心动过速组24h的最快心率、最慢心率、平均心率增高,心率变异的RR间期标准差(SDNN)、RR间期平均值标准差(SDANN)、相邻RR间期差值均方根(RMSSD)、相邻RR间期差值＞50 ms所占百分比(PNN50)、三角指数(HRVI)等时域指标有所降低,频域指标低频域值(LF)增高,高频域值(HF)降低.结论 心率变异是评价心脏自主神经系统功能的指标.交感神经兴奋,迷走神经功能相对降低,可减弱对窦房结的支配.

Sinus tachycardia on heart rate variability

Objective To further understand the heart rate variability, and to investigate the cardiac au- tonomic nervous system function. Methods 58 cases were selected for the study and they were divided into two groups according to ECG diagnosis results： sinus tachycardia group and normal control group. The 24-hour ambu- latory ECG of all subjects were analyzed and the fastest heart rate, the slowest heart rate, average heart rate were observed. The heart rate variability was analyzed by using the time domain and frequency domain method. Results Compared with eontrol group, the fastest heart rate, the slowest heart rate and average heart rate in sinus tachy- cardia group were significantly increased. The time domain index such as heart rate variability, SDNN, SDANN, RMSSD, PNN50, HRVI in sinus taehycardia group were significantly decreased. The frequency domain indexes of LF, HF were reduced in sinus tachycardia group. Conclusion The heart rate variability is the index of evaluating the cardiac autonomic nervous system function. The experiment shows that the excitation of sympathetic nerves and the function reduces relatively in vagus nerve can weak the domination to sinus node.