摘要: 目的 研究心房颤动（房颤）伴长R-R间期的老年患者心率变异性（HRV）的特征及相关因素。方法 收集98例房颤患者，行动态心电图（Holter）HRV分析，次日晨时抽空腹血查儿茶酚胺浓度。根据Holter中是否伴有长R-R间期（>2.5 s）分为病例组及对照组2组，比较2组的R-R间期总体标准差（SDNN）、每5 min R-R间期均值的标准差（SDANN）、相邻R-R间期标准差的平均值（rMSSD）、相邻R-R间期差值＞50 ms所占的百分比（pNN50）、血浆儿茶酚胺（肾上腺素、去甲肾上腺素）浓度水平。结果 98例房颤患者分为病例组(33例)和对照组(65例)2组，2组年龄、吸烟史、高血压病史、糖尿病史等比较差异均无统计学意义（P均>0.05）。病例组的SDNN、SDANN、rMSSD、pNN50分别为（143.5±29.5）ms、（95.9±37.0）ms、（100.0±28.6）ms、（57.0±17.6）%，对照组分别为（115.7±32.8）ms、（78.6±31.5）ms、（81.8±23.3）ms、（49.5±15.9）%。病例组的HRV参数均高于对照组，差异有统计学意义（P < 0.05）。病例组及对照组的血浆肾上腺素浓度分别为（30.2±20.6）pg/ml、（41.8±26.7）pg/ml；病例组及对照组的血浆去甲肾上腺素浓度分别为（120.5±59.3）pg/ml、（187.4±89.2）pg/ml，病例组均低于对照组，差异有统计学意义（P均 < 0.05）。结论 合并长R-R间期的老年房颤患者SDNN等HRV参数增高，血浆儿茶酚胺浓度降低，提示自主神经功能失调[迷走神经张力增高和（或）交感神经张力降低]在其机制中发挥重要作用。

Abstract: Objective To investigate the characteristics of heart rate variability and related factors in elderly patients diagnosed with atrial fibrillation complicated with long R-R interval. Methods Clinical data of 98 atrial fibrillation patients were collected. All patients received dynamic electrocardiogram (Holter) and detection of heart rate variability. In the next morning, the concentration of catecholamine was quantitatively measured by fasting blood test. All participants were divided into the case and control groups according to the presence of long R-R interval (>2.5 s). The standard deviation of NN interval (SDNN), standard deviation of average NN interval (SDANN), root mean square of successive differences (rMSSD), pNN50 and plasma concentration of catecholamine (epinephrine and noradrenaline) were statistically compared between two groups. Results Ninety-eight atrial fibrillation patients were assigned into the case (n=33) and control groups (n=65). No statistical difference was identified in age, medical history of smoking, hypertension and diabetes mellitus between two groups (all P>0.05). In the case group, the heart rate variability related parameters including SDNN, SDANN, rMSSD and pNN50 were (143.5±29.5) ms, (95.9±37.0) ms, (100.0±28.6) ms and (57.0±17.6)%, significantly higher compared with (115.7±32.8) ms, (78.6±31.5) ms, (81.8±23.3) ms and (49.5±15.9)% in the control group, respectively (all P < 0.05). In the case group, the plasma concentrations of epinephrine and noradrenaline were (30.2±20.6) and (120.5±59.3) pg/ml, considerably lower than (41.8±26.7) and (187.4±89.2) pg/ml in the control group (both P < 0.05). Conclusions For atrial fibrillation elderly patients complicated with long R-R interval, HRV parameters, such as SDNN are increased, whereas the plasma concentration of catecholamine is down-regulated, prompting that autonomic nerve dysfunction (increased vagus nervous tension and/or decreased sympathetic nervous tension) plays a pivotal role in the underlying mechanism.