Impaired baroreflex sensitivity and sympathovagal balance in syndrome X
Impaired baroreflex sensitivity and sympathovagal balance in syndrome X
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DOI：
10.1016/s0002-9149(98)00493-7
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发表时间：
1998-10-01
影响因子：
2.8
通讯作者：
Coats, AJS
中科院分区：
文献类型：
--
作者：
Adamopoulos, S;Rosano, GMC;Coats, AJS
X综合征中描述了心脏功能的自主神经控制的改变。然而，X综合征患者心血管系统自主控制的特征尚未得到充分研究，因此，本研究的目的是探讨压力感受器敏感性和交感迷走神经平衡在X综合征中的作用。研究组包括12名X综合征患者，12名年龄和性别匹配的冠状动脉疾病对照患者，以及12名年龄和性别匹配的无心脏病证据的对照患者。压力感受器敏感性通过计算回归线来评估，回归线将苯肾上腺素诱导的收缩压升高与RR间期的伴随变化联系起来。交感迷走神经平衡通过在时间和频率域中使用心率变异性和测量静息和递增自行车运动期间的血浆去甲肾上腺素来评估。X综合征患者的压力感受器敏感性显著低于正常对照组（7.4 +/- 1.2 vs 16.8 +/- 2.3 ms/mm Hg; p <50 ms，X综合征患者相邻RR间期差异的均方根较低，高频成分的对数值较正常对照组低。X综合征患者与对照缺血患者相比，压力感受器敏感性降低的趋势不显著（7.4 +/- 2 vs 12.2 +/- 1.3 ms/mmHg）。与两个对照组相比，X综合征患者的低频与高频比值也呈非显著性升高趋势。3组间静息或运动时的去甲肾上腺素水平或运动诱导的去甲肾上腺素升高均无差异。缺血性患者和正常受试者之间的压力感受器敏感性或心率变异性测量也没有差异。显著相关性（r = 0.80，p
Alterations of autonomic nervous control of cardiac function have been described in syndrome X. The characteristics, however, of the autonomic control of the cardiovascular system in patients with syndrome X have not been adequately studied thus, the aim of the present study was to investigate the role of baroreceptor sensitivity and sympathovagal balance in syndrome X. The study group included 12 patients with syndrome X, 12 age- and sex-matched control patients with coronary artery disease, and 12 age- and sex-marched controls with no evidence of heart disease. Baroreceptor sensitivity was evaluated by calculating the regression line relating phenylephrine-induced increases in systolic blood pressure to the attendant changes in the RR interval. Sympathovagal balance was assessed by using heart rate variability in the time and frequency domain and measuring plasma norepinephrine at rest and during incremental bicycle exercise. Baroreceptor sensitivity was significantly reduced in syndrome X compared with that in control normal subjects (7.4 +/- 1.2 vs 16.8 +/- 2.3 ms/mm Hg; p 50 ms, lower root-mean-square of the difference of adjacent RR intervals, and lower logarithmic value of the high-frequency component in patients with syndrome X compared with normal subjects. A nonsignificant trend toward lower baroreceptor sensitivity was found in patients with syndrome X compared with control ischemic patients (7.4 +/- 2 vs 12.2 +/- 1.3 ms/mm Hg). A nonsignificant trend toward a higher value of the low- to high frequency ratio was also observed in patients with syndrome X than in both control groups, No difference was detected in norepinephrine levels either at rest or during exercise or in the exercise-induced norepinephrine increase between the 3 groups. No difference was also observed between ischemic patients and normal subjects in either baroreceptor sensitivity or heart rate variability measurements. A significant correlation (r = 0.80, p