Postural dysautonomia in response to head-up tilt in a military pilot aspirant: Aeromedical considerations

Intolerance to orthostasis encompasses a group of responses on assumption of upright posture. One such response is postural dysautonomia. One of the types of postural dysautonomia is postural orthostatic tachycardia syndrome, which is characterised by an increase in heart rate of more than 30 bpm without hypotension along with other features of dysautonomia on attaining an erect posture, either actively or passively. This paper brings out a case of postural dysautonomia in a pilot aspirant in response to Head-up tilt (HUT) test. A 23-year-old female military pilot aspirant reported for evaluation of Syncope and Air Sickness. She gave a history of solitary episode of loss of consciousness on ground while preparing for an early morning sortie. She was diagnosed with a case of neurocardiogenic syncope and was put back to flying training. Subsequently, after about 2 months, she developed features of air sickness while flying and also could not tolerate preliminary motion sickness desensitisation at her unit. A thorough medical evaluation failed to reveal any neurocardiological abnormality. Before commencing the air sickness desensitisation protocol at the Institute of Aerospace Medicine, she was subjected to HUT during which she developed signs and symptoms suggestive of postural dysautonomia. A test retest assessment with repeat HUT and passive standing test revealed similar responses.

Acrocianosis como primera manifestación de síndrome de taquicardia postural ortostática en dos adolescentes / Acrocyanosis as the first manifestation of orthostatic postural tachycardia syndrome in two adolescents

La acrocianosis desencadenada por la bipedestación como signo principal de la taquicardia postural ortostática (POTS, por su sigla en inglés) es poco conocida, aunque bien descrita en la bibliografía especializada. Se describen dos casos clínicos de adolescentes que consultaron en el Servicio de Urgencias por acrocianosis e intolerancia al ortostatismo. El primer paciente, de 13 años, presentó un aumento de la frecuencia cardíaca de 40 latidos por minuto (lpm) al pasar del decúbito a la bipedestación. El segundo, de 14 años, presentó un aumento de la frecuencia cardíaca hasta 125 lpm al incorporarse. En ambos, la tensión arterial y los estudios complementarios fueron normales. El POTS se define en la edad pediátrica como una intolerancia al ortostatismo que se acompaña de aumento de la frecuencia cardíaca excesiva sin hipotensión arterial. Conocer la acrocianosis como primer signo de presentación es de utilidad para el diagnóstico de esta enfermedad y para evitar estudios complementarios innecesarios.

Acrocyanosis triggered by standing position as the main sign of postural orthostatic tachycardia (POTS) is little known but well described in scientific literature. In pediatric age, POTS is defined as orthostatic intolerance that is accompanied by an excessive increase in heart rate without arterial hypotension. We present two clinical reports of teenagers who were admitted in the Emergency Department with acrocyanosis and orthostatic intolerance. The first patient was 13-year-old and had an increase in heart rate of 40 bpm when moving from a reclining to a standing position. The second patient was 14-year-old and showed an increasing in heart rate up to 125 bpm after upright position. In both patients' blood pressure was normal and all investigations were negative. They were finally diagnosed with postural orthostatic tachycardia. Recognizing acrocyanosis as first sign of this disease is useful for diagnosis and can help to avoid unnecessary testing.

Comparison of Health Education, Oral Rehydration Solution, Metoprolol and Midodrine Intervention in Children with POTS

Introduction: The postural orthostatic tachycardia syndromeis heterogeneous group of disorder. When a healthy individualstands up, gravity causes about 10%-15% of his or her bloodto settle in the abdomen or limbs. This pooling of bloodmeans that less blood reaches the brain, the result of whichcan be a feeling of lightheadedness, darkening of vision, oreven fainting. Hence, the aim of the present study was toevaluate the clinical features and the effectiveness of nonpharmacological and pharmacological treatment in patientswith POTS.Material and Methods: A retrospective medical recordanalysis of the patients referred to pediatric cardiology unitof our Second Xiangya Hospital of Central South Universitysince June 2003 to February 2010 was done. This studyincluded 33 children patients aged 6 to 16 years old among17 male (mean 10.62±2.88 years) and 16 female (mean11.81±1.64 years) after medication within 14 days to 6 monthswith follow up record.Results: The most common presenting symptoms of POTSwere found to be dizziness or light-headedness (66.66%)followed by chest tightness (30.30%), syncope (27.27%),headache (24.24%) and pallor (24.24%) respectively. About75.5% of children patients met diagnostic criteria for POTSduring 5 to 10 minute of HUTT. There was significant statisticdifference in heart rate between before and after treatment oftotal patients during 5 and 10 minute of HUTT (P<0.05). Theoverall improvement found in 24(72.72%) patients whereas9(27.27%) patients not respond to the given treatment regimen.Conclusion: The most common presenting symptom of POTSwas dizziness or light-headedness. Most of the patients meetdiagnostic criteria for POTS during 5 to 10 minute durationof HUTT. Health education, ORS, propranolol and midodrinewere effective in treatment of POTS and helpful to diminishthe upright tachycardia. Whereas health education and healtheducation with midodrine hydrochloride treatment methodwere more likely effective than health education with ORSand health education with metoprolol method

Small Fiber Neuropathy and Postural Orthostatic Tachycardia Syndrome after Human Papillomavirus Vaccination

We describe a 44-year-old woman with paresthesia, fatigue, and palpitation, 10 days after human papillomavirus (HPV) vaccination. The quantitative sensory test showed abnormal detection threshold in her foot. Tilt test result indicated postural orthostatic tachycardia syndrome. Symptoms were improved after immunomodulating therapy, pain control drug, and oral beta blocker medication. This is first case report for small fiber neuropathy and autonomic dysfunction after HPV vaccination in Korea.

Autonomic Dysfunction in Dizziness Clinic / 대한평형의학회지

Orthostatic dizziness is a common type of dizziness. In general, orthostatic dizziness is provoked by standing or tilting, and subsided by supine position. The patient with orthostatic intolerance complains multiple symptoms such as dizziness, palpitation, lightheadness, fatigue and rarely syncope. Common orthostatic intolerance is orthostatic hypotension (classic, initial, transient, and delayed orthostatic hypotension) and postural orthostatic tachycardia syndrome. Transcranial Doppler is a noninvasive technique that provides real-time measurement of cerebral blood flow velocity. It can be useful for understanding the relationship between orthostatic symptoms and cerebral autoregulatory function. The reciprocal causal relationship between vestibular and autonomic dysfunction should always be kept in mind.

Syndromes of Orthostatic Intolerance: Pathophysiology and Diagnosis / 대한소아신경학회지

Orthostasis means standing upright. Thus, orthostatic intolerance (OI) can be simply defined as “the development of symptoms during upright standing, that are relieved by recumbency.” However, OI might be a confusing topic in clinical practice because of the recent appreciation of the condition's clinical variant, emerging understanding of its diverse mechanisms, and its nomenclature, which seems to change annually. OI is not fatal but should be differentiated from potentially lethal disorders, including seizures or cardiogenic syncope. Typical signs and symptoms include loss of consciousness, lightheadedness, and visual difficulties. However, patients also experience multiple and nonspecific symptoms that seem unrelated to orthostatic intolerance, such as headache, fatigue, nausea, abdominal pain, and exercise intolerance. This review was aimed at expanding the comprehension of this confusing and easily missed topic by providing better understanding of the normal hemodynamic response to orthostasis and the basic pathophysiological concepts of major syndromes of OI.

Orthostatic Hypotension and Postural Orthostatic Tachycardia Syndrome in Children: Comparison of Clinical Features and Neurophysiology Test / 대한소아신경학회지

PURPOSE: The clinical characteristics and neuropsychological tests of orthostatic hypotension (OH) and postural orthostatic tachycardia syndrome (POTS) in children were compared. METHODS: From August 2011 to April 2015, we enrolled patients who visited hospital with dizziness or syncope. According to the results of head-up tilt test (HUTT), the patients were classified into 4 groups; OH group, POTS group, normal group I who had no orthostatic symptom during HUTT, and normal group II who had orthostatic symptom during HUTT. RESULTS: Eighty-eight patients were enrolled with 11(12.5%) in OH group, 13(14.7%) in POTS group, 49(55.7%) in normal group I and 15(17.0%) in the normal group II. During HUTT, the temporal changes of systolic, diastolic, and mean blood pressure of OH group were significantly different from those of POTS group, normal group I, and normal group II. Heart rate changes after tilt showed increase trend in all 4 groups and there was no significant different between OH and POTS group. In normal group II, the temporal changes of diastolic and mean blood pressure were similar to those in POTS group and were significantly different from normal group I. In the autonomic nervous system test, the heart rate response to deep breathing (HRDB) was significantly different between normal group I and II CONCLUSIONS: In pediatric OH patients, heart rate may be increased with blood pressure fall. And if orthostatic symptoms are associated with HUTT, we should not exclude OI even if the test result do not meet the criteria for diagnosis.

Co-morbidity of vasovagal syncope and postural tachycardia syndrome with allergic diseases in children / 北京大学学报(医学版)

Objective:To explore the clinical characteristics of the co-morbidity of vasovagal syncope (VVS) and postural tachycardia syndrome (POTS) with allergic diseases in children.Methods:A retrospective analysis was launched to summarize the clinical data of children with VVS and POTS.They were divided into allergic group and non-allergic group according to the history of allergic diseases.The participants' clinical characteristics were compared between allergic group and non-allergic group using independent sample t test or rank sum test;composition comparisons were completed by Chi-square test.Bi-variate correlation analysis was used to explore the association between eosinophil percentage/count and symptom scores/frequency of syncope episodes.A P value ＜ 0.05 was defined as statistically significant.Results:Sixty-seven children complaining of orthostatic intolerance (43 patients diagnosed as VVS and 24 cases diagnosed as POTS) were enrolled.Totally 21 cases (31％) had allergic diseases,inclu ding allergic rhinitis,atopic eczema,asthma,as well as food allergy.And allergic rhinitis is the most common co-morbidity.There were no significant differences between the two groups in age,gender ratio,height,body weight and basement blood pressure.Compared with the non-allergic group,the allergic group showed later onset age (year) (11 ± 2 vs.9 ± 3,P ＜ 0.05) of orthostatic intolerance and shorter course of the diseases (month) [8.0 (0.1,0.1) vs.24.0 (0.1,144.0),P＜0.05].The frequency of syncope episodes in the allergic group among VVS children (times per month) [2.50 (0.08,30.00) vs.O.25 (0.03,5.00),P ＜ 0.05] was much higher than that in the non-allergic group.Additionally,the eosinophil percentage (％) [3.50 (0.70,0.59) vs.1.65 (0.30,6.20),P＜0.001] and eosino phil count (×109) [0.18 (0.05,0.71) vs.0.10 (0.02,0.38),P＜0.001] were increased in the allergic group.However,there were no remarkable differences in the results of head-up tilt test in children with VVS or in the maximum change of heart rate during standing test in children with POTS were involved.Conclusion:Allergic diseases are common co-morbidities in children with both VVS and POTS.Allergic rhinitis is the most common co-morbidity.Children with co-morbidity of VVS/POTS and allergic diseases had a later onset of symptoms of orthostatic intolerance,and were more likely to be hospitalized for intensive attacks of symptoms during a short period when compared with those without allergic diseases.Children diagnosed as VVS combined with allergic diseases had more frequent episodes of syncope.

Reduced Systolic Volume: Main Pathophysiological Mechanism in Patients with Orthostatic Intolerance? / Volume Sistólico Reduzido: Mecanismo Fisiopatológico Principal em Pacientes com Intolerância Ortostática?

Abstract Background: Orthostatic intolerance patients' pathophysiological mechanism is still obscure, contributing to the difficulty in their clinical management. Objective: To investigate hemodynamic changes during tilt test in individuals with orthostatic intolerance symptoms, including syncope or near syncope. Methods: Sixty-one patients who underwent tilt test at - 70° in the phase without vasodilators were divided into two groups. For data analysis, only the first 20 minutes of tilting were considered. Group I was made up of 33 patients who had an increase of total peripheral vascular resistance (TPVR) during orthostatic position; and Group II was made up of 28 patients with a decrease in TPVR (characterizing insufficient peripheral vascular resistance). The control group consisted of 24 healthy asymptomatic individuals. Hemodynamic parameters were obtained by a non-invasive hemodynamic monitor in three different moments (supine position, tilt 10' and tilt 20') adjusted for age. Results: In the supine position, systolic volume (SV) was significantly reduced in both Group II and I in comparison to the control group, respectively (66.4 ±14.9 ml vs. 81.8±14.8 ml vs. 101.5±24.2 ml; p<0.05). TPVR, however, was higher in Group II in comparison to Group I and controls, respectively (1750.5± 442 dyne.s/cm5 vs.1424±404 dyne.s/cm5 vs. 974.4±230 dyne.s/cm5; p<0.05). In the orthostatic position, at 10', there was repetition of findings, with lower absolute values of SV compared to controls (64.1±14.0 ml vs 65.5±11.3 ml vs 82.8±15.6 ml; p<0.05). TPVR, on the other hand, showed a relative drop in Group II, in comparison to Group I. Conclusion: Reduced SV was consistently observed in the groups of patients with orthostatic intolerance in comparison to the control group. Two different responses to tilt test were observed: one group with elevated TPVR and another with a relative drop in TPVR, possibly suggesting a more severe failure of compensation mechanisms.

Resumo Fundamento: O mecanismo fisiopatológico de pacientes com intolerância ortostática ainda é obscuro, contribuindo para a dificuldade no manejo clínicos desses pacientes. Objetivo: Investigar as alterações hemodinâmicas durante teste de inclinação (tilt teste) em indivíduos com sintomas de intolerância ortostática, incluindo síncope ou pré-síncope. Métodos: Sessenta e um pacientes, com tilt teste a 70º negativo na fase livre de vasodilatador, foram divididos em dois grupos. Para análise dos dados foram considerados apenas os primeiros 20 minutos de inclinação. Grupo I (33 pacientes) que tiveram elevação da resistência vascular periférica total (RVPT) durante posição ortostática e Grupo II (28 pacientes) com queda da RVPT (caracterizando insuficiência de resistência vascular periférica). O grupo controle consistia de indivíduos saudáveis e assintomáticos (24 indivíduos). Os parâmetros hemodinâmicos foram obtidos por um monitor hemodinâmico não invasivo em 3 momentos distintos (posição supina, tilt 10' e tilt 20'), ajustados para idade. Resultados: Na posição supina, o volume sistólico (VS) foi significantemente reduzido tanto no Grupo II quanto no I, quando comparado ao do Grupo controle, respectivamente (66,4 ±14,9 ml vs. 81,8±14,8 ml vs. 101,5±24,2 ml; p<0,05.) A RVPT, no entanto, foi mais elevada no Grupo II, quando comparada a do Grupo I e controles, respectivamente (1750,5± 442 dyne.s/cm5 vs.1424±404 dyne.s/cm5 vs. 974,4±230 dyne.s/cm5; p<0,05). Na posição ortostática, aos 10', houve repetição dos achados, com valores absolutos inferiores de VS Comparado aos controles (64,1±14,0 ml vs 65,5±11,3 ml vs 82,8±15,6 ml; p<0,05). A RVPT, todavia, apresentou queda relativa no Grupo II comparado ao I. Conclusão: Volume sistólico reduzido foi consistentemente observado nos grupos de pacientes com intolerância ortostática, quando comparado ao grupo controle. Foram observadas duas respostas distintas ao teste de inclinação: um grupo com elevação de RVPT e outro com queda relativa desta, indicando, possivelmente, falência mais acentuada dos mecanismos de compensação.

Orthostatic Intolerance Syndrome

Orthostatic intolerance is the inability to tolerate an upright posture as a consequence of varying degrees of autonomic nervous system dysfunction. Orthostatic intolerance syndromes can be classified into at least 3 categories: 1) orthostatic hypotension, 2) neurally mediated (reflex) syncope, and 3) postural orthostatic tachycardia syndrome. In this review, we discuss the pathophysiology and etiologies of orthostatic hypotension and postural orthostatic tachycardia syndrome, and propose their diagnostic and therapeutic alternatives.

Meta-analysis of effect of β-blockers on treatment of postural orthostatic tachycardia syndrome in children / 中华实用儿科临床杂志

Objective To evaluate the efficacy of β-blockers in treatment of postural orthostatic tachycardia syndrome( POTS) in children. Methods Clinical controlled trials were collected from a variety of medical electronic databases including PubMed(1990-2014),Excerpta Medica database(EMBASE 1990-2014),ELSEVIER(1990-2014),China National Knowledge Internet(CNKI 1990—2014) and WANFANG(1990—2014) by 2 researchers simultaneously and respectively based on same inclusion and exclusion criteria. Studies were assessed based on the Juni scale evaluation,and the Meta-analysis was conducted using the Rev-Man 5. 0 software. Results In total 8 clinical trials were included out of over 200 papers. Possible publication bias were assessed by Funnel plot analysis. Meta analy-sis of the 8 studies demonstrated that compared with the placebo group, metoprolol group showed significantly better ef-ficacy in treating children with POTS(RR=0. 37,95%CI:0. 21-0. 64,P=0. 000 5). Furthermore,these included trials were divided into different subgroups based on trial design ( randomized controlled trial/non-randomized con-trolled trial and Scored/N-scored) . Although no statistical heterogeneities were detected within each subgroups by the subgroup analysis,marked heterogeneities were found among subgroups; there was no significant difference of efficacy between metoprolol and placebos in treating POTS in non-randomized controlled trial group(RR=0. 68,95%CI:0. 45-1. 02,P=0. 06). Conclusions Low-dose metoprolol is effective in treating POTS,but the conclusion still needs to be tested by more large-scaled,multi-centered and standardized clinical randomized controlled trials.

Advance in postural orthostatic tachycardia syndrome in children / 国际儿科学杂志

Postural orthostatic tachycardia syndrome (POTS)is a clinical syndrome and the main clinical manifestation is the increase of heart rate.POTS is significantly related to position change.During the first 10 min of position change from supine to standing,if heart rate increases over a certain extent,POTS can be diagnosised.The pathogenesis of POTS has not been completely clear.The current studies show that it is closely related to the changes of central blood volume,dysautonomia,muscle pump dysfunction,vascular endothelium function disorder,etc.

Efficacy of oral saline plus health education and autonomic nerve exercise on the treatment of postural orthostatic tachycardia syndrome in children / 中华实用儿科临床杂志

Objective To compare the efficacy of oral rehydration salts(ORS),health education and autonomic nervous activity training with health education and autonomic nervous activity training on children with postural orthostatic tachycardia syndrome (POTS).Methods Fifty-two children with POTS based on head-up test or head-up tilt test were divided into ORS treatment group and conventional treatment group.ORS treatment group included 33 children,and they received ORS and health education and autonomic nervous activity training therapy.Conventional treatment group included 19 children who received health education and autonomic nervous activity training therapy only.Telephone follow-ups were made after the therapy for 1-3 months.The contents of follow-up were the compliance of ORS treatment,the implementation of health education and POTS related symptom frequency.Results 1.The compliance of doctor's advice in ORS treatment group was better than that in the conventional treatment group.2.There was no significant difference in the symptom scores before therapy between ORS treatment group and conventional treatment group [(6 ± 3) scores in ORS treatment group vs (5 ± 3) scores in conventional treatment group,t =0.799,P ＞ 0.05].After 1 to 3 months therapy,the symptom scores were significantly lowered in both groups.The symptom scores in ORS treatment group was lower than those of the conventional treatment group[(2 ± 1) scores in ORS treatment group vs(3 ± 1)scores in conventional treatment,t =-2.189,P ＜ 0.05].3.If the therapy was determined to be effective when the symptom scores decreased by at least 2 scores,the effective rate in ORS treatment group was significantly higher than that of the conventional treatment group(78.8％ in ORS treatment group vs 42.1％ in conventional treatment group,x2 =7.169,P ＜ 0.01).Conclusions The efficacy of ORS,health education and autonomic nervous activity training therapy is better than that of the health education and autonomic nervous activity training therapy only in POTS children.

The follow-up study on the treatment of children with postural orthostatic tachycardia syndrome / 国际儿科学杂志

Objective To compare the short-term and long-term therapeutic effects of oral rehydration salts,metoprolol or midodrine hydrochloride in children with postural tachycardia syndrome (POTS).Methods Two hundred and forty-four children with POTS diagnosed in the First Hospital Peking University of from Dec.2004 to Jan.2013 were followed up in clinics or by telephone.They were divided into oral rehydration salt group (n =75),metoprolol group (n =66) and midodrine hydrochloride group (n =103).The patients were followed up for 3 ～ 100 months.Results After 3 months of treatment,the symptom scoring of the three groups was improved greatly as compared with the baseline data.Therapeutic effect of midodrine hydrochloride group was significantly superior to metoprolol group and oral rehydration salt group (x2 =8.750,P =0.013).One hundred and forty-two out of 244 children were followed up and their head-up tilt test(HUT)was repeated.The HR increment of children in 3 groups became smaller as compared with before treatment (P ＜ 0.05).After follow-up,the symptom scoring was improved greatly as compared with the baseline scoring (P ＜ 0.05).The short-term effect of midodrine hydrochloride group was significantly better than that of metoprolol group or oral rehydration salt group (x2 =8.750,P =0.013).The Kaplan-Meier curves showed that the long-term effect of midodrine hydrochloride group was significantly superior to metoprolol group and oral rehydration salt group (89.3％vs 78.8％,P =0.033;89.3％ vs 76.0％,P =0.002).Conclusion Oral rehydration salts,midodrine hydrochloride or metoprolol were all effective for POTS in children.And the short-term and long-term effect of midodrine hydrochloride might be superior to metoprolol and oral rehydration salts.

A Case of Postural Orthostatic Tachycardia Syndrome Associated with Migraine and Fibromyalgia

Postural orthostatic tachycardia syndrome (POTS) refers to the presence of orthostatic intolerance with a heart rate (HR) increment of 30 beats per minute (bpm) or an absolute HR of 120 bpm or more. There are sporadic reports of the autonomic nervous system dysfunction in migraine and fibromyalgia. We report a case of POTS associated with migraine and fibromyalgia. The patient was managed with multidisciplinary therapies involving medication, education, and exercise which resulted in symptomatic improvement. We also review the literature on the association between POTS, migraine, and fibromyalgia.

Orthostatic symptoms does not always manifest during tilt-table test in pediatric postural orthostatic tachycardia syndrome patients / 소아과

PURPOSE: Chronic day-to-day symptoms of orthostatic intolerance are the most notable features of postural orthostatic tachycardia syndrome (POTS). However, we have encountered patients with such symptoms and excessive tachycardia but with no symptoms during the tilt-table test (TTT). We aimed to investigate whether POTS patients with chronic orthostatic intolerance always present orthostatic symptoms during the TTT and analyze the factors underlying symptom manifestation during this test. METHODS: We retrospectively examined patients who presented with POTS at the Gyeongsang National University Hospital between 2008 and 2011. Diagnosis of POTS was based on chronic day-to-day orthostatic intolerance symptoms as well as excessive tachycardia during the TTT. The patients were divided two groups depending on the presentation of orthostatic symptoms during the TTT. Clinical data and the results of the TTT were compared between these groups. RESULTS: In 22 patients, 7 patients (31.8%) did not present orthostatic symptoms during the test. Diastolic blood pressure (BP) was significantly lower in the symptom-positive group. The head-up tilt resulted in a significant increase in diastolic BP in the symptom-negative group (P=0.04), while systolic BP had a tendency to decrease in the symptom-positive group (P=0.06). CONCLUSION: Significant patients with POTS did not present orthostatic symptoms during the TTT despite having chronic daily symptoms. This finding may be important for establishing definitive diagnostic criteria for pediatric POTS. Development of symptoms during TTT might be related to low diastolic BP and abnormal compensatory responses to orthostasis.

Taquicardia postural ortostática en 15 pacientes: disautonomía compleja / Postural orthostatic tachycardia syndrome (POTS): Report of 15 cases

Background: Patients with postural orthostatic tachycardia syndrome (POTS) report dizziness, lightheadedness, weakness, blurred vision, and fatigue upon standing. The diagnosis of the syndrome is made when an orthostatic intolerance and tachycardia appear in the standing position. Aim: To report 15 patients with POTS. Material and Methods: Review of Tilt test reports in a period of 15 years. Those reports in which orthostatic postural tachycardia and symptoms compatible with POTS appeared, were selected for analysis. Results: We identified 15 patients (3.1% of all positive Tilt test reports) with compatible signs and symptoms. There was a lag of 8 -10 years between the onset of symptoms and the time of diagnosis. Most patients complained of orthostatic intolerance, dizziness and frequent fainting. Orthostatic tachycardia and symptoms occurred on average after 2.9 and 6.1 minutes, respectively,of staying in the standing position. These patients had a high frequency of family history of syncope orpresyncope (66% frequency) and hyper mobility syndrome (53% prevalence). Only 33% of the patients reported relief of their symptoms after being treated (most of them with fludrocortisone). Most patients that reported little or no relief, did not use medications or were treated for a short period. Conclusions: POTS syndrome is uncommon but disturbs quality of life of those who suffer it. Its association with hyper mobility syndromes must be investigated.

Clinical Characteristics and Neurophysiologic Findings of Postural Orthostatic Tachycardia Syndrome in Pediatric Patients / 대한소아신경학회지

PURPOSE: No domestic report has been published on postural orthostatic tachycardia syndrome (POTS) in adolescents, although it has been increasingly studied in adolescents since first reported in 1999. This study analyzed the clinical characteristics and neurophysiologic findings of POTS in Korean pediatric patients. METHODS: We reviewed the medical records of pediatric patients (<18 years) with POTS who visited Gyeongsang National University Hospital in Jinju between January 2008 and March 2010. All patients underwent tilt-table and autonomic function tests. RESULTS: We identified 18 patients (72.2% male, mean age 13.6 +/- 2.1 years). The mean orthostatic heart rate increment was 43.0 +/- 9.1 beats/min. Most patients (83.3%) had mild autonomic dysfunction, and three (16.6%) had moderate autonomic dysfunction. Half of patients had sudomotor abnormalities in the lower limbs, implying peripheral postganglionic sympathetic denervation in the legs. Of these patients, 66.6% also had adrenergic impairment. The degree of autonomic dysfunction correlated with the orthostatic heart rate increment (P=0.047). Patients needing pharmacologic treatment had a higher orthostatic heart rate increment (P=0.017), composite autonomic severity score (P=0.002), and sudomotor score (P=0.006), compared with non-pharmacologically treated patients. CONCLUSION: Autonomic dysfunction or autonomic neuropathy seems to be the main pathophysiology of POTS in pediatric patients, especially adolescents. Further, the degree of autonomic dysfunction influenced the prognosis of POTS. Additionally, unlike previous adult series, most of our patients were male. This male predominance in adolescents suggests that the growth spurt is an important factor triggering POTS at this age.

A Case of Multiple Sclerosis with Sick Sinus Syndrome and Postural Orthostatic Tachycardia Syndrome / The Japanese Journal of Rehabilitation Medicine

A 19-year-old girl was admitted to our hospital with nausea, vomiting, hiccups, constipation and syncope. After hiccups or vomiting sinus arrest developed and lasted more than 5-8 seconds. She lost consciousness every one hour. Based on an electrocardiographic diagnosis of sick sinus syndrome (SSS), a temporary pacemaker was implanted. The next day, although her syncope and bradycardia disappeared, she had orthostatic tachycardia of over 120 beats/minute and swelling of the legs, which led to a diagnosis of postural orthostatic tachycardia syndrome (POTS). Neurologically, she showed the right-sided tongue deviation and parasympathetic system disorders revealed by coefficient of variation of R-R interval (CV_R-R), the Achner eye-ball pressure test, the valsalva ratio, and the head-up-tilt test. Brain MRI disclosed a small hyperintense lesion on a T2-weighted image with gadolinium enhancement in the right dorsal medulla including the hypoglottis nucleus and the posterior nucleus of vagus. After steroid pulse therapy (methyl prednisolone 1 g/day×3 days, 5 times) was administered, this lesion became smaller and finally disappeared. Before the lesion disappeared, she was able to begin rehabilitation by wearing elastic stockings and treatment with midodrine hydrochloride. The following year, she developed other MRI-proven brain lesions, suggestive of demyelination. Such a spinal and temporal distribution of lesions led to a diagnosis of multiple sclerosis (MS). A case of POTS caused by MS has not been reported previously, however, MS often affects the medullary paraventricular regions associated with autonomic failures. Autonomic failures often prevent patients from experiencing early rehabilitations. We should promptly give symptomatic treatment against autonomic failures, which leads to good patient recovery not only in patient vitality but also functionality.