白大衣高血压患者的心率变异性

Heart Rate Variability in White Coat Hypertension

目的探讨白大衣高血压(WCH)患者心率变异性的变化。方法选初诊的1,2级原发性高血压(EH)患者[诊室血压和24h动态血压均示140≤收缩压<180mmHg和(或)90≤舒张压<110mmHg],WCH患者(诊室血压>140/90mmHg,24h动态血压日间平均血压<135/85mmHg),正常血压者(诊室血压和24h动态血压均<140/90mmHg)各35例,通过24h动态心电图监测,比较3组血压、心率变异性时域和频域指标的差异。结果和正常血压组相比,EH组和WCH组相邻正常RR间期标准差(SDNN),正常RR间期差值的方差(RMSSD),高频功率均明显下降[SDNN:正常血压组(132.2±21.5)比EH组(115.9±18.9)比WCH组(120.6±17.5)ms;RMSSD:正常血压组(36.8±9.3)比EH组(28.6±8.9)比WCH组(27.5±8.5)ms;高频功率:正常血压组(206.8±99.7)比EH组(159.5±86.6)比WCH组(161.1±84.5)ms2/Hz;均P<0.05],低频功率与高频功率比增加(正常血压组2.1±0.9比EH组3.7±1.2比WCH组3.9±1.1;P<0.05)。EH组和WCH组两组之间,上述指标比较差异无统计学意义。结论WCH患者心率变异性有变化,提示存在自主神经功能紊乱。

Objective To investigate the change of heart rate variability（HRV） in patients with white coat hy pertension （WCH）. Methods Participants were classified as essential hypertension （EH） group （n=35）, white coat hypertension （WCH） group （n=35）, normotension （NT） group （n=35） based on clinic and 24 h ambulatory blood pressure monitoring. The time and frequency-domain measures of HRV were measured by 24 h ambulatory electrocardiographic recording. Results Compared with NT controls, the standard deviation of normal-to-normal intervals （SDNN}, rate-mean-square of the difference of successive RR intervals （RMSSD） and high frequence （HF） in the patients with EH and WCH were significantly decreased [ SDNN ： NT（ 132.2 ± 21.5 ） vs EH （ 115.9 ± 18.9 ） vs WCH（120.6±17.5）ms; RMSSD： NT（36.8±9.3）vs EH（28.6±8.9）vs WCH（27.5±8.5）ms; HF： NT （206.8±99.7）vs EH（159.5±86.6）vs WCH（161.1±84.5）ms2/Hz; all P〈0.05], while the low frequence（LF）/ HF ratio increased （NT 2.1 ± 0.9 vs EH 3.7± 1.2 vs WCH 3.9± 1.1, P〈0.05）. No significant difference of above parameters of HRV were found between the EH and WCH groups （P〉0.05）. Conclusion These changes in the parameters of HRV showed cardiac autonomic nerve dysfunction in white coat hypertensive patients.