原发性高血压合并2型糖尿病患者心率变异性与心脏变时功能不全的特点及相关性

目的 探讨原发性高血压合并2型糖尿病患者的心率变异性和心脏变时功能不全特点. 方法 原发性高血压合并2型糖尿病患者与健康人各40例,行24 h动态心电图检查,计算心脏变异性指标SDNN、SDANN、RMSSD、PNN50;行平板运动试验检查,计算运动中最大心率、心脏变时指数、心率储备率,分析心脏变时指数和心率储备率与SDNN、SDANN、RMSSD、PNN50的相关性. 结果 原发性高血压合并2型糖尿病患者SDNN、SDANN 、RMSSD、PNN50均较健康者降低（P〈0.01）.最大心率、心脏变时指数、心率储备率明显低于健康者（P〈0.01）;SDNN、SDANN、RMSSD及PNN50与心脏变时指数（r=0.522、0.472、0.337、0.321）和心率储备率（r=0.541、0.480、0.351、0.285）均存在明显正相关. 结论 原发性高血压合并2型糖尿病患者心脏自主神经受损明显,表现为迷走神经功能减退和交感神经兴奋性增高.

Characteristics of Heart Rate Variability and Chronotropic Incompetence in Hypertensive Patients with Type 2 Diabetes Mellitus

Objective To investigate features of heart rate variability （HRV） and chronotropie incompetence in hypertensive patients with type 2 diabetes mellitus（T2DM）. Methods The standard deviation of NN intervals（SDNN）, the standard deviation of 5-minute means of NN intervals （SDANN）, the root-mean-square of differences of adjacent RR intervals （RMSSD） and the percent of differences between adjacent NN intervals 〉50 ms （PNN50） on 24 hours dynamic ECG, and the maximal heart rate（Max HR）, chronotropic response index（CRI） and heart rate reserve（HRR） during exercise test were measured in 40 hypertensive patients with T2DM （T2DM group） and 40 healthy people （control group）. Results SDNN, SDANN, RMSSD, PNNS0, Max HR, CRI and HRR were significantly lower in T2DM group than in control group （P〈0.01）. SDNN, SDANN, RMSSD and PNN50 were positively correlated to CRI （r=0.522, 0.472, 0.337, 0.321） and HRR（r=0.541, 0.480, 0.351, 0.285）, respectively. Conclusion Cardiac autonomic nervous modulation is disturbed in hypertensive patients with T2DM, which may manifest as reduced vagal tone and enhanced sympathetic tone.