Postural Orthostatic Tachycardia Syndrome Associated with COVID-19: A Narrative Review.

Postural orthostatic tachycardia syndrome (POTS) is a complex condition marked by an atypical autonomic response to standing, leading to orthostatic intolerance and significant tachycardia without accompanying hypotension. In recent studies, a considerable number of individuals recovering from COVID-19 have been reported to experience POTS within 6 to 8 months post-infection. Key symptoms of POTS include fatigue, difficulty with orthostatic tolerance, tachycardia, and cognitive challenges. The underlying causes of POTS following COVID-19 remain unknown, with various theories proposed such as renin-angiotensin-aldosterone system (RAAS) dysregulation, hyperadrenergic reaction, and direct viral infection. Healthcare professionals should be vigilant for POTS in patients who have recovered from COVID-19 and are experiencing signs of autonomic dysfunction and use diagnostic procedures such as the tilt-up table test for confirmation. COVID-19-related POTS should be approached with a holistic strategy. Although many patients show improvement with initial non-drug treatments, for subjects who do not respond and exhibit more severe symptoms, medication-based therapies may be necessary. The current understanding of COVID-19-related POTS is limited, underscoring the need for more research to increase knowledge and enhance treatment approaches.

Individually tailored exercise in patients with postural orthostatic tachycardia syndrome related to post-COVID-19 condition - a feasibility study.

Postural orthostatic tachycardia syndrome (POTS) occurs in approximately 30% of people with highly symptomatic post-COVID-19 condition (PCC). It involves several symptoms that limit physical and psychological functions and cause reduced quality of life. Evidence for different treatments of POTS and PCC is limited, and this study aimed to evaluate the feasibility of individually tailored physical exercise. The secondary aim of the study was to evaluate the preliminary effectiveness of this intervention. Twenty-six participants (81% female, median age 41 years) were enrolled and performed individually tailored endurance and strength training, with progression, for twelve weeks. During the intervention period, the participants had weekly support from a physiotherapist. Feasibility was evaluated with good compliance, with 76% adherence to exercise prescription and 96% completing the study protocol. The treatment was safe, and the evaluation methods (questionnaires, physical assessments, and accelerometer monitoring) were judged to be feasible. After the intervention, improvements in symptom burden as well as in psychological and physical functions were observed. In conclusion, future randomized controlled trials can be performed with only minor adjustments and could include questionnaires, physical assessment and accelerometer monitoring, which were demonstrated as feasible by this study.

Acceleration index predicts efficacy of orthostatic training on postural orthostatic tachycardia syndrome in children.

The objective of this study was to examine the utility of the acceleration index observed in an electrocardiogram (ECG) for the prediction of the effectiveness of orthostatic training in pediatric patients diagnosed with postural orthostatic tachycardia syndrome (POTS). This investigation focused on children diagnosed with POTS and undergoing orthostatic training at the Department of Pediatrics of Peking University First Hospital from January 2012 to October 2022. Specifically, patients hospitalized from January 2012 to December 2019 were included in the training set (54 cases), while those hospitalized from January 2020 to October 2022 were included in the external validation set (37 cases). All children received a 3-month orthostatic training, and the baseline symptom score (SS) was calculated in agreement with the pretreatment orthostatic intolerance symptom frequency. Additionally, we determined post-treatment SS during follow-up via telephone after the 3-month treatment. Children with a decrease in post-treatment SS by ≥ 50% of the baseline were considered as responders; otherwise, they were considered as non-responders. Demographic data (age, sex, and body mass index), hemodynamic parameters (supine blood pressure, time to achieve a positive standing test, maximum increase in heart rate during the standing test, maximal heart rate reached during the standing test, and blood pressure at the point of maximal heart rate during the standing test), and electrocardiographic parameters (RR interval in the supine position, shortest RR interval in the upright position, and acceleration index) were collected from all the children prior to treatment. Univariate and multivariate regression analysis were conducted to investigate factors associated with the efficacy of orthostatic training. The predictive value of these indicators for the therapeutic effectiveness of orthostatic training in children with POTS was evaluated using receiver operating characteristic (ROC) analysis, and the indicators were validated using the validation set. Among the 54 children in the training set, 28 responded to orthostatic training, and 26 were nonresponsive. Compared with the non-responders, the responders demonstrated a significant reduction in acceleration index (P < 0.01). The ROC curve for the predictive value of the acceleration index exhibited an area under the curve = 0.81 (95% confidence interval: 0.685-0.926). With the acceleration index threshold < 27.93%, the sensitivity and specificity in the prediction of orthostatic training efficacy among children with POTS were 85.7% and 69.2%, respectively. The external validation results demonstrated that using acceleration index < 27.93% as the threshold, the sensitivity, specificity, and accuracy of predicting orthostatic training efficacy among children with POTS were 89.5%, 77.8%, and 83.8%, respectively. CONCLUSIONS: Electrocardiographic acceleration index can be used to predict the effectiveness of orthostatic training in treating children with POTS. WHAT IS KNOWN: • Postural orthostatic tachycardia syndrome (POTS) is a chronic orthostatic intolerance involving multiple mechanisms. Autonomic dysfunction is one of the main mechanisms of POTS in children and could be treated with orthostatic training. • In order to improve the efficacy of orthostatic training in children with POTS, it is particularly important to identify the patients with autonomic dysfunction as the main mechanism before the treatment. WHAT IS NEW: • We found acceleration index of the electrocardiogram (ECG) can be used as a satisfactory index to predict the efficacy of orthostatic training in the treatment of POTS in children. • Using the acceleration index to predict the efficacy of orthostatic training on POTS in children is easy to be popularized in hospitals at all levels because it is non-invasive, convenient, and not expensive.

Long-Term POTS Outcomes Survey: Diagnosis, Therapy, and Clinical Outcomes.

BACKGROUND: Limited data exist on long-term outcomes in individuals with postural orthostatic tachycardia syndrome (POTS). We designed an electronic questionnaire assessing various aspects of outcomes among patients diagnosed and treated in a single-center pediatric POTS clinical program. METHODS AND RESULTS: The LT-POTS (Long Term POTS Outcomes Survey) included questions about quality of life, symptoms, therapies, education, employment, and social impact of disease. Patients age≤18 years at POTS diagnosis who were managed in the Children's Hospital of Philadelphia POTS Program were included. A total of 227 patients with POTS responded with sufficient data for interpretation. The mean age of respondents was 21.8±3.5 years. The median age of symptom onset was 13 (interquartile range 11-14) years, with mean 9.6±3.4 years symptom duration. Multiple cardiovascular, neurologic, and gastrointestinal symptoms were reported. Symptom prevalence and severity were worse for female patients, with 99% of patients reporting ongoing symptoms. Quality of life showed moderate function and limitation, with more severe limitations in energy/fatigue and general health. Nearly three quarters of patients had diagnostic delays, and over half were told that their symptoms were "in their head." Multiple medications were used and were felt to be effective, whereas fewer nonpharmacologic interventions demonstrated efficacy. Nearly 90% of patients required continued nonpharmacologic therapy to control symptoms. CONCLUSIONS: POTS is a chronic disorder leading to significant disability with a range of multisystem problems. Although symptoms can be modifiable, it rarely spontaneously resolves. Improved understanding of POTS presentation and therapeutic approaches may inform provider education, improve diagnostic success, and help patients self-advocate for appropriate medical management approaches.

Deep abdominal breathing reduces heart rate and symptoms during orthostatic challenge in patients with postural orthostatic tachycardia syndrome.

BACKGROUND AND PURPOSE: This study investigated the effects of deep abdominal breathing on cardiovascular parameters and symptoms in patients with postural orthostatic tachycardia syndrome (POTS) during head-up tilt-table (HUT) challenge. METHODS: Thirty POTS patients completed two consecutive rounds of 10-min HUT in a crossover design. One round was HUT without intervention, and one round combined the HUT with deep breathing at a rate of 6 breaths/min. Cardiovascular parameters, including mean blood pressure and maximum and mean heart rate (HR), were measured supine and standing. Symptoms were assessed using the Vanderbilt Orthostatic Symptom Score (VOSS). RESULTS: During the breathing technique, the mean HR increase was -7.35 bpm (95% confidence interval [CI] = -11.71 to -2.98), and the maximum HR increase was -6.27 bpm (95% CI = -11.85 to -0.68, p = 0.041), significantly lower compared to normal breathing. Additionally, improvements were observed in all absolute cardiovascular parameters during standing, with VOSS symptoms simultaneously and significantly decreasing by -5.38 (95% CI = -10.43 to -0.36). CONCLUSIONS: Slow deep abdominal breathing can act as a simple technique to reduce the standing HR increase upon HUT in patients with POTS. This suggests that modulation of the cardiopulmonary neurocircuits and the respiratory pump may reduce HR increase and symptoms in patients with POTS. The findings of this study highlight the use of a safe, zero-cost, and simple behavioral tool to suggest to POTS patients for symptom relief apart from standard treatment. The observed improvements in cardiovascular parameters and symptoms offer a promising therapeutic approach for patients in times of inadequate treatment options.

Postural orthostatic tachycardia syndrome in a Thai male patient.

Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous autonomic disorder. All patients have exaggerated tachycardia upon standing, but the pathophysiology may be diverse. We present a young adult Thai male with a chief complaint of palpitations while in an upright posture since childhood. The patient underwent a modified Ewing test battery which included standing test, deep breathing, and Valsalva maneuver. His heart rate increased more than 30 beats per minute (bpm) during repeated active stand tests (65 to 110 bpm and 77 to 108 bpm), while upright diastolic blood pressure increased more than 10 mmHg. Normal Valsalva ratio (2.01 and 1.86) and baseline heart rate variability (HFRRI = 4030.24 ms2 and 643.92 ms2) indicated intact vagal function. High low-frequency systolic blood pressure variability (LFSBP = 20.93 mmHg2), increased systolic blood pressure overshoot in phase IV of Valsalva (42 mmHg), and increased upright diastolic blood pressure indicated a hyperadrenergic state. In conclusion, the overall autonomic profile was compatible with hyperadrenergic POTS. Thus, we confirmed the first male POTS case reported in Thailand. We demonstrated the importance of autonomic function testing with continuous measurements to confirm POTS. There is a need for further research in POTS in Thailand.

Long COVID: lights and shadows on the clinical characterization of this emerging pathology.

More than 800 million individuals have contracted SARSCOV2 infection worldwide. It was estimated that almost 10-20% of these might suffer from Long COVID. It is a multisystemic syndrome, which negatively affects the quality of life with a significant burden of health loss compared to COVID negative individuals. Moreover, the risk of sequelae still remains high at 2 years in both nonhospitalized and hospitalized individuals. This review summarizes studies regarding long COVID and clarifies the definitions, the risk factors and the management of this syndrome. Finally, it delves into the most frequent long-term outcomes, especially postural orthostatic tachycardia syndrome" (POTS), myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), brain fog, and their therapeutical possibilities.

The Contribution of Psychological Symptoms to Cognitive Difficulties in Youth With Postural Orthostatic Tachycardia Syndrome and Chronic Pain.

INTRODUCTION: Subjectively experienced cognitive difficulties are common in youth with postural orthostatic tachycardia syndrome. The pathophysiological and psychological contributions of these cognitive impairments remain unclear. METHOD: Participants were 96 adolescents and young adults diagnosed with postural orthostatic tachycardia syndrome and admitted to an intensive pain treatment program. Participants completed cognitive assessment and measures of postural orthostatic tachycardia syndrome symptoms, pain intensity, pain catastrophizing, anxiety, depression, and functional disability. RESULTS: Self-reported autonomic symptom intensity, but not severity of heart rate change, was associated with cognitive performance. Symptoms of depression were associated with decreases in most measures of cognitive functioning. Pain intensity, pain catastrophizing, and depression but not cognitive scores and physiological measures, were significant predictors of disability. CONCLUSION: Depression appears to be a significant contributor to the cognitive difficulties in youth with postural orthostatic tachycardia syndrome. These findings highlight the importance of assessing and treating affective symptoms in this population along with medical and lifestyle approaches to treating postural orthostatic tachycardia syndrome symptoms.

Phenylephrine alters phase synchronization between cerebral blood velocity and blood pressure in ME/CFS with orthostatic intolerance.

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) with orthostatic intolerance (OI) is characterized by neurocognitive deficits perhaps related to upright hypocapnia and loss of cerebral autoregulation (CA). We performed N-back neurocognition testing and calculated the phase synchronization index (PhSI) between arterial pressure (AP) and cerebral blood velocity (CBV) as a time-dependent measurement of cerebral autoregulation in 11 control (mean age = 24.1 yr) and 15 patients with ME/CFS (mean age = 21.8 yr). All patients with ME/CFS had postural tachycardia syndrome (POTS). A 10-min 60° head-up tilt (HUT) significantly increased heart rate (109.4 ± 3.9 vs. 77.2 ± 1.6 beats/min, P < 0.05) and respiratory rate (20.9 ± 1.7 vs. 14.2 ± 1.2 breaths/min, P < 0.05) and decreased end-tidal CO2 (ETCO2; 33.9 ± 1.1 vs. 42.8 ± 1.2 Torr, P < 0.05) in ME/CFS versus control. In ME/CFS, HUT significantly decreased CBV compared with control (-22.5% vs. -8.7%, P < 0.005). To mitigate the orthostatic CBV reduction, we administered supplemental CO2, phenylephrine, and acetazolamide and performed N-back testing supine and during HUT. Only phenylephrine corrected the orthostatic decrease in neurocognition by reverting % correct n = 4 N-back during HUT in ME/CFS similar to control (ME/CFS = 38.5 ± 5.5 vs. ME/CFS + PE= 65.6 ± 5.7 vs. Control 56.9 ± 7.5). HUT in ME/CFS resulted in increased PhSI values indicating decreased CA. Although CO2 and acetazolamide had no effect on PhSI in ME/CFS, phenylephrine caused a significant reduction in PhSI (ME/CFS = 0.80 ± 0.03 vs. ME/CFS + PE= 0.69 ± 0.04, P < 0.05) and improved cerebral autoregulation. Thus, PE improved neurocognitive function in patients with ME/CFS, perhaps related to improved neurovascular coupling, cerebral autoregulation, and maintenance of CBV.NEW & NOTEWORTHY We evaluated cognitive function before and after CO2, acetazolamide, and phenylephrine, which mitigate orthostatic reductions in cerebral blood velocity. Neither CO2 nor acetazolamide affected N-back testing (% correct answers) during an orthostatic challenge. Only phenylephrine improved upright N-back performance in ME/CFS, as it both blocked hyperventilation and increased CO2 significantly compared with those untreated. And only phenylephrine resulted in improved PSI values in both ME/CFS and control while upright, suggesting improved cerebral autoregulation.

Small fiber neuropathy in children, adolescents, and young adults with chronic orthostatic intolerance and postural orthostatic tachycardia syndrome: A retrospective study.

PURPOSE: To determine in children, adolescent and young adult (CAYA) patients presenting with Orthostatic Intolerance (OI) or Postural Orthostatic Tachycardia Syndrome (POTS) associated with the additional symptoms of neuropathic discomfort (pain, paresthesia and/or allodynia): 1) the incidence of small fiber neuropathy, and 2) assess if there was serologic evidence for an underlying inflammatory or autoimmune state. METHODS: A cohort of 109 CAYA patients with the above symptoms underwent epidermal skin biopsy for nerve fiber density. Blood biomarkers for inflammation were tested (CRP, ESR, ANA, complement (C3), thyroid function testing with antibodies (thyroid peroxidase antibody and thyroglobulin antibody), and cytokine panel 13). Patients completed a Quality of Health questionnaire. Statistical analysis was performed using Wilcoxon rank sum tests. RESULTS: In CAYA patients with OI or POTS and neuropathic symptoms, skin biopsy for small fiber neuropathy was abnormal in 53 %. The sample population was predominantly female and Caucasian with moderately decreased perceived quality of health. OI /POTS patients with small fiber neuropathy had a 3-fold probability of having a positive ANA or anti-thyroid antibody, suggesting an underlying autoimmune or inflammatory process. CONCLUSION: Our data suggest a link between OI and POTS and small fiber neuropathy. Small fiber neuropathy was found by skin biopsy in over half of the patients tested. OI and Postural orthostatic tachycardia patients with small fiber neuropathy expressed multiple markers suggesting an underlying autoimmune or inflammatory process. Future research will be done to evaluate the symptomatic implication of SFN and whether immune or pharmacologic manipulation can alter patient symptoms.

The use and effectiveness of exercise for managing postural orthostatic tachycardia syndrome in young adults with joint hypermobility and related conditions: A scoping review.

PURPOSE: Postural Orthostatic Tachycardia Syndrome (POTS) is a form of dysautonomia. It may occur in isolation, but frequently co-exists in individuals with hypermobile variants of Ehlers-Danlos Syndrome (EDS) and related conditions (chronic fatigue syndrome [CFS] and fibromyalgia). Exercise is recommended for non-pharmacological POTS management but needs to be individualised. This scoping review explores the current literature on use and effectiveness of exercise-based management for POTS, with specific focus on individuals with joint hypermobility and related conditions who experience hypermobility, and/or pain, and/or fatigue. METHODS: A systematic search, to January 2023, of Medline, EMBASE, AMED, CINAHL and the Cochrane library was conducted. Studies that reported on adolescents and adults who had been diagnosed with POTS using standard criteria and underwent an exercise-based training intervention were included. RESULTS: Following full-text screening, 10 articles were identified (2 randomised control trials, 4 comparative studies and 4 case reports). One comparative study reported a small subset of participants with EDS and one case report included an individual diagnosed with CFS; the remainder investigated a wider POTS population. Overall, 3 months of endurance followed by resistance exercise, graduating from the horizontal-to-upright position reduced POTS symptoms and improved quality-of-life. CONCLUSION: The findings highlight a paucity of higher-level studies documenting exercise for POTS management in people with joint hypermobility and related conditions. Results from the wider POTS population demonstrate exercise is safe and effective. Large, well-designed clinical studies exploring exercise for POTS management adapting to meet the complex musculoskeletal and non-musculoskeletal features of symptomatic joint hypermobility are needed.

Fifteen-minute consultation: Pathophysiology of postural orthostatic tachycardia syndrome in children and adolescents: diagnosis and management strategies.

Postural orthostatic tachycardia syndrome (POTS) affects children and adolescents-normally fit and well and yet troubled by a myriad of everyday symptoms. Understanding the pathophysiology of this not uncommon disorder together with a review of the clinical features may well assist the attending clinicians to arrive at a clear diagnosis without the need for extensive testing and multiple investigations. Simple lifestyle measures such as increasing fluid intake, electrolyte and/or salt supplements, adequate sleep, not missing out on meals and instituting an exercise programme to improve muscle tone and strength may avoid the need of pharmacological management. These simple measures may benefit symptoms which generally improve as adulthood approaches. In addition, it is important to recognise the comorbidities that may be associated with POTS, each of which may require specific management strategies. This paper reviews the pathophysiology, clinical features and recommended treatment in the management of POTS.

Effect of High Dietary Sodium Intake in Patients With Postural Tachycardia Syndrome.

BACKGROUND: High sodium intake is recommended for the treatment of postural tachycardia syndrome (POTS) to counteract the hypovolemia and elevated plasma norepinephrine that contribute to excessive orthostatic tachycardia, but evidence of its efficacy is not available. OBJECTIVES: This study tested whether a high sodium (HS) diet reduces orthostatic tachycardia (Δ heart rate) and upright heart rate compared with a low sodium (LS) diet in POTS patients, and secondarily its effect on plasma volume (PV) and plasma norepinephrine. METHODS: A total of 14 POTS patients and 13 healthy control subjects (HC), age 23 to 49 years, were enrolled in a crossover study with 6 days of LS (10 mEq sodium/day) or HS (300 mEq sodium/day) diet. Supine and standing heart rate, blood pressure, serum aldosterone, plasma renin activity, blood volume, and plasma norepinephrine and epinephrine were measured. RESULTS: In POTS, the HS diet reduced upright heart rate and Δ heart rate compared with the LS diet. Total blood volume and PV increased, and standing norepinephrine decreased with the HS compared with the LS diet. However, upright heart rate, Δ heart rate, and upright norepinephrine remained higher in POTS than in HC on the HS diet (median 117 beats/min [interquartile range: 98 to 121 beats/min], 46 beats/min [interquartile range: 32 to 55 beats/min], and 753 pg/ml [interquartile range: 498 to 919 pg/ml] in POTS vs. 85 beats/min [interquartile range: 77 to 95 beats/min], 19 beats/min [interquartile range: 11 to 32 beats/min], and 387 pg/ml [interquartile range: 312 to 433 pg/ml] in HC, respectively), despite no difference in the measured PV. CONCLUSIONS: In POTS patients, high dietary sodium intake compared with low dietary sodium intake increases plasma volume, lowers standing plasma norepinephrine, and decreases Δ heart rate. (Dietary Salt in Postural Tachycardia Syndrome; NCT01547117).

Postural orthostatic tachycardia syndrome (POTS) and other autonomic disorders after COVID-19 infection: a case series of 20 patients.

OBJECTIVE: To describe clinical features, diagnostic findings, treatments, and outcomes in patients with new-onset postural orthostatic tachycardia syndrome (POTS) and other autonomic disorders following SARS-CoV-2 infection (COVID-19). METHODS: We retrospectively reviewed medical records for patients who presented with persistent neurologic and cardiovascular complaints between April and December 2020 following COVID-19 infection. RESULTS: Twenty patients (70% female) were included in this study.Fifteen had POTS, 3 had neurocardiogenic syncope, and 2 had orthostatic hypotension. Six patients had abnormalities on cardiac or pulmonary testing, and 4 had elevated autoimmune or inflammatory markers. All patients were treated with non-pharmacologic therapies, and most required pharmacologic therapies. Six to 8 months after COVID-19, 17 (85%) patients had residual autonomic symptoms, with 12 (60%) unable to return to work. CONCLUSIONS: POTS can follow COVID-19 in previously healthy patients. Appropriate diagnostic investigations and therapies are necessary to identify and treat autonomic dysfunction after COVID-19.

Decreased Stroke Volume and Venous Return in School Children with Postural Tachycardia Syndrome.

In postural tachycardia syndrome (POTS), a subtype of orthostatic intolerance, the changes in hemodynamics due to postural changes are poorly understood. We speculated that inappropriate venous return, which may occur in the upright position in patients with school-aged POTS, could be detected by echocardiography. Our prospective study was conducted with 100 POTS patients (45 boys and 55 girls), aged 13.1 ± 1.5 years and 52 age- and sex-matched healthy subjects (control). Echocardiography was performed in the supine and sitting positions. Cardiac parameters [stroke volume index, cardiac index, heart rate, and the maximum inferior vena cava diameter (max IVC)] were evaluated in addition to pulse pressure. Unlike the control subjects, POTS patients demonstrated decreased stroke volume index (P = 0.02) and max IVC (P < 0.01) irrespective of posture. The rates of max IVC change did not differ between control and POTS groups. The enrolled POTS patients were divided into two subgroups [dilatation (n = 57) and contraction (n = 43)] based on whether the change rate of max IVC was less than zero or not. The contraction group showed a significantly higher heart rate than the dilatation group with respect to posture (P = 0.03), indicating the poor response of peripheral vessels in the lower limbs only in the contraction group. In conclusion, echocardiographic assessment detected decreased stroke volume and venous return in POTS. The changes in max IVC in response to postural changes may indicate an underlying pathophysiology in POTS.

Cutaneous alpha-synuclein deposition in postural tachycardia patients.

OBJECTIVE: To report a case series of patients with neuropathic POTS and cutaneous phosphorylated alpha-synuclein (P-SYN) deposition on skin biopsy and compare these to neuropathic POTS patients without P-SYN deposition. METHODS: The medical history, physical examination findings, autonomic function testing, and skin biopsy neuropathology of patients under the age of 50 with a postural tachycardia and a diagnosis of POTS were retrospectively reviewed. Included patients completed the composite autonomic severity score (COMPASS 31), the Wood Mental Fatigue Inventory, the Epworth Sleepiness scale, the REM Behavior Disorder Questionnaire, the Patient-Reported Outcomes Measurement Information System (PROMIS-10), and the Gastroparesis Cardinal Symptom Index. RESULTS: Of 296 patients seen with POTS, 22 patients with suspected neuropathic POTS had skin biopsies performed during their evaluation. Seven of 22 patients had P-SYN present on skin biopsy, while 15 individuals did not. Those with P-SYN on biopsy: (1) were more likely to be male; (2) had features of REM sleep behavioral disorder; (3) reported less sleepiness and cognitive impairment; and (4) noted greater symptoms of gastroparesis. On autonomic testing, the group with P-SYN deposition was more likely to have a hypertensive response to tilt-table testing and abnormal QSART responses. INTERPRETATION: Phosphorylated alpha-synuclein deposition is present in some postural tachycardia patients with neuropathic features. Individuals with a postural tachycardia and cutaneous phosphorylated alpha-synuclein deposition may be distinguished from other patients with neuropathic POTS.

The Postural Tachycardia Syndrome (PoTS) Bladder-Urodynamic Findings.

OBJECTIVE: To evaluate the urodynamics (UDS) of patients with postural tachycardia syndrome (PoTS). METHODS: Patients with a confirmed diagnosis of PoTS referred by the department of neuro-cardiology to the neuro-urology were identified and their UDS were retrospectively reviewed. RESULTS: In total, 50 patients (47 = 94.0% female) with confirmed PoTS and available UDS were identified. Mean age of females and males was 32.4 and 28.2 years, P = .15. Intermittent self-catheterisation was being used by 15/47 (31.9%) females at assessment. Detrusor overactivity was observed in 6 females (12.8%) (all at end fill and associated with urgency). In total, 14 (29.8%) females had no sensation of filling. No patients had an "unsafe" bladder. In total, 15/47 (31.9%) of women were unable to void with UDS catheters. Straining was reported in 22/35 (68.8%) of females. The female bladder outflow obstruction index = PDetQmax - 2.2(Qmax) was over 5 in 10/28 (35.7%) and over 18 in 5 (17.9%). The bladder contractility index = PDetQmax + 5Qmax was under 100 in 18/28 (28.6%) women. CONCLUSION: The UDS of patients with "PoTS bladder" often demonstrate a poorly sensate but stable and safe bladder with functional obstruction and impaired bladder contractility that may necessitate straining or intermittent self-catheterisation.

gAChR antibodies in children and adolescents with acquired autoimmune dysautonomia in Japan.

OBJECTIVE: Patients with acquired autonomic dysfunction may have antibodies specific to the ganglionic nicotinic acetylcholine receptor (gAChR). However, the clinical features of children and adolescents with acquired autonomic dysfunction (AAD) remain unclear. This study aimed to determine the clinical features of pediatric patients with acquired autonomic dysfunction. METHODS: This study retrospectively examined a series of patients of AAD with serum gAChR antibodies who were referred to our laboratory for antibody testing between January 2012 and April 2019. The study included 200 patients (<20 years, 20 cases; ≥20 years, 175 cases) with clinical features of AAD. RESULTS: Upon comparing pediatric and adult patients, we found that antecedent infection and autonomic symptoms at onset with gastrointestinal symptoms occurred more frequently in children with AAD. We confirmed that four children (20.0%) met the diagnostic criteria for postural orthostatic tachycardia syndrome (POTS). A significantly higher number of children than adults had POTS (P = 0.002). In addition, upper GI dysfunction was more prevalent in children than in adults (P = 0.042). In particular, nausea and vomiting occurred in 60.0% of children with AAD and in 21.1% of adults (P < 0.001). The frequency of paralytic ileus was significantly higher in children with AAD (20.0%) relative to adults (6.3%) (P = 0.030). Regarding extra-autonomic manifestations, encephalopathy was more frequent in children (15.0%) than in adults (1.1%) (P < 0.001). INTERPRETATION: Pediatric AAD patients have their own clinical characteristics, and these features may be unique to children and adolescents.