Autonomic nervous system dysfunction in adolescents with postural orthostatic tachycardia syndrome and chronic fatigue syndrome is characterized by attenuated vagal baroreflex and potentiated sympathetic vasomotion

作     者：Stewart, JM 

作者机构：New York Med Coll Ctr Pediat Hypotens Dept Pediat Valhalla NY 10595 USA 

出 版 物：《PEDIATRIC RESEARCH》 (Pediatr. Res.)

年 卷 期：2000年第48卷第2期

页      面：218-226页

核心收录：

学科分类：1002[医学-临床医学] 100202[医学-儿科学] 10[医学] 

基　　金：NIAID NIH HHS [1RO3-AI45954-01] Funding Source: Medline 

摘      要：The objective was to determine the nature of autonomic and vasomotor changes in adolescent patients with orthostatic tachycardia associated with the chronic fatigue syndrome (CFS) and the postural orthostatic tachycardia syndrome (POTS). Continuous electrocardiography and arterial tonometry was used to investigate the heart rate and blood pressure responses before and 3-5 min after head-up tilt in 22 adolescents with POTS and 14 adolescents with CFS, compared with control subjects comprising 10 healthy adolescents and 20 patients with simple faint. Heart rate and blood pressure variability, determined baroreceptor function using transfer function analysis, and measured cardiac vagal and adrenergic autonomic responses were calculated using timed breathing and the quantitative Valsalva maneuver. Two of 10 healthy controls and 14 of 20 simple faint patients experienced vasovagal syncope during head-up tilt. By design, all CFS and POTS patients experienced orthostatic tachycardia, often associated with hypotension. R-R interval and heart rate variability were decreased in CFS and POTS patients compared with control subjects and remained decreased with head-up tilt. Low-frequency (0.05-0.15 Hz) blood pressure variability reflecting vasomotion was increased in CFS and POTS patients compared with control subjects and increased further with head-up tilt. This was associated with depressed baroreflex transfer indicating baroreceptor attenuation through defective vagal efferent response. Only the sympathetic response remained. Heart rate variability declined progressively from normal healthy control subjects through syncope to POTS to CFS patients, Timed breathing and Valsalva maneuver were most often normal in CFS and POTS patients, although abnormalities in select individuals were found. Heart rate and blood pressure regulation in POTS and CFS patients are similar and indicate attenuated efferent vagal baroreflex associated with increased vasomotor tone. Loss of beat-to-bea