Semi-supervised exercise training program more effective for individuals with postural orthostatic tachycardia syndrome in randomized controlled trial.

PURPOSE: Exercise like any medication requires the correct dose; to be effective the appropriate frequency, duration, and intensity are necessary. This study aimed to assess if a semi-supervised exercise training (ET) program would be more effective at improving aerobic fitness (VO2PEAK), exercise tolerance, and symptoms in individuals with postural orthostatic tachycardia syndrome (POTS) compared to the standard of care (SOC). METHODS: Subjects were randomized to either the ET or SOC groups (n 26 vs. 23; age 33 ± 11 vs. 37 ± 10 years; VO2PEAK 66 ± 15 vs. 62 ± 15% predicted, ET vs. SOC respectively, p > 0.05). Composite Autonomic Symptom Score (COMPASS 31), 10 min stand test, and cardiopulmonary exercise test were performed at baseline and following 12 weeks. The ET group received an exercise consultation and eight semi-supervised in-person or virtual exercise sessions. RESULTS: The ET group demonstrated a greater improvement in VO2PEAK, higher or longer tolerance for baseline peak workload, and more often had a delayed symptom onset with exercise than the SOC group (ΔVO2PEAK 3.4 vs. - 0.2 mL/min/kg, p < 0.0001, ΔWorkload 19 ± 17 vs. 0 ± 10 W; Workload time 63 ± 29 vs. 22 ± 30 s; onset-delay 80% vs. 30%, p < 0.05). Individuals in the ET group reported a significant improvement in orthostatic intolerance domain score (p = 0.02), but there was not a significant difference in the improvement in total COMPASS score (- 11.38 vs. - 6.49, p = 0.09). CONCLUSION: Exercise training was more effective with greater improvements in aerobic fitness, orthostatic symptoms, and exercise tolerance for individuals with POTS when intensity and progression were personalized and delivered with minimal supervision compared to the SOC.

[A 10-year retrospective analysis of spectrums and treatment options of orthostatic intolerance and sitting intolerance in children].

OBJECTIVE: To analyze the disease spectrums underlying orthostatic intolerance (OI) and sitting intolerance (SI) in Chinese children, and to understand the clinical empirical treatment options. METHODS: The medical records including history, physical examination, laboratory examination, and imagological examination of children were retrospectively studied in Peking University First Hospital from 2012 to 2021. All the children who met the diagnostic criteria of OI and SI were enrolled in the study. The disease spectrums underlying OI and SI and treatment options during the last 10 years were analyzed. RESULTS: A total of 2 110 cases of OI and SI patients were collected in the last 10 years, including 943 males (44.69%) and 1 167 females (55.31%) aged 4－18 years, with an average of (11.34±2.84) years. The overall case number was in an increasing trend over the year. In the OI spectrum, postural tachycardia syndrome (POTS) accounted for 826 cases (39.15%), followed by vasovagal syncope (VVS) (634 cases, 30.05%). The highest proportion of SI spectrum was sitting tachycardia (STS) (8 cases, 0.38%), followed by sitting hypertension (SHT) (2 cases, 0.09%). The most common comorbidity of OI and SI was POTS coexisting with STS (36 cases, 1.71%). The highest proportion of treatment options was autonomic nerve function exercise (757 cases, 35.88%), followed by oral rehydration salts (ORS) (687 cases, 32.56%), metoprolol (307 cases, 14.55%), midodrine (142 cases, 6.73%), ORS plus metoprolol (138 cases, 6.54%), and ORS plus midodrine (79 cases, 3.74%). The patients with POTS coexisting with VVS were more likely to receive pharmacological intervention than the patients with POTS and the patients with VVS (41.95% vs. 30.51% vs. 28.08%, χ2= 20.319, P < 0.01), but there was no significant difference in the proportion of treatment options between the patients with POTS and the patients with VVS. CONCLUSION: POTS and VVS in children are the main underlying diseases of OI, while SI is a new disease discovered recently. The number of children with OI and SI showed an increasing trend. The main treatment methods are autonomic nerve function exercise and ORS. Children with VVS coexisting with POTS were more likely to take pharmacological treatments than those with VVS or POTS only.

Postural Orthostatic Tachycardia Syndrome: Prevalence, Pathophysiology, and Management.

Postural orthostatic tachycardia syndrome (POTS) is a debilitating disease that predominantly affects young women. It is a multifactorial disorder that is characterized by severe tachycardia and orthostatic intolerance. Patients with POTS experience a variety of cardiac, neurological, and immunological symptoms that significantly reduce quality of life. In this review, a comprehensive framework is provided to aid in helping identify and treat patients with POTS. Given its heterogenous nature, it is crucial to understand each component of POTS in relation to one another instead of distinct parts. The framework highlights the overlap among the five main subtypes of POTS based on its pathophysiology (neuropathic, hypovolemic, primary hyperadrenergic, joint-hypermobility-related, and immune-related). Emphasis is placed on incorporating a multidisciplinary approach when treating patients with POTS, especially with a new focus towards immunotherapy. Although research has advanced our knowledge of POTS, there is still a critically unmet need to further our understanding and provide patients with the relief they need.

Evaluation of syncope: focus on diagnosis and treatment of neurally mediated syncope.

Syncope, defined as a transient loss of consciousness secondary to global cerebral hypoperfusion, is common in the general population. The single most helpful "test" in the evaluation of patients with syncope is a thoughtful history, with recent evidence that structured histories are remarkably effective in arriving at a diagnosis. In addition to the history, physical examination, and electrocardiogram, arriving at a diagnosis of syncope can involve monitoring and provocative strategies. The majority of patients with syncope have neurally mediated syncope and a favourable prognosis. The management of neurally mediated syncope continues to largely revolve around education, avoidance of triggers, reassurance, and counter-pressure maneuvers. The evidence surrounding medical therapy in vasovagal syncope is not strong to date. Pacemaker therapy is reasonable in older patients with recurrent, unpredictable syncope with pauses, but should be considered as a last resort in younger patients.

Adolescent fatigue, POTS, and recovery: a guide for clinicians.

Many teenagers who struggle with chronic fatigue have symptoms suggestive of autonomic dysfunction that may include lightheadedness, headaches, palpitations, nausea, and abdominal pain. Inadequate sleep habits and psychological conditions can contribute to fatigue, as can concurrent medical conditions. One type of autonomic dysfunction, postural orthostatic tachycardia syndrome, is increasingly being identified in adolescents with its constellation of fatigue, orthostatic intolerance, and excessive postural tachycardia (more than 40 beats/min). A family-based approach to care with support from a multidisciplinary team can diagnose, treat, educate, and encourage patients. Full recovery is possible with multi-faceted treatment. The daily treatment plan should consist of increased fluid and salt intake, aerobic exercise, and regular sleep and meal schedules; some medications can be helpful. Psychological support is critical and often includes biobehavioral strategies and cognitive-behavioral therapy to help with symptom management. More intensive recovery plans can be implemented when necessary.

Does goal-directed fluid therapy affect postoperative orthostatic intolerance?: A randomized trial.

BACKGROUND: Early mobilization is important for postoperative recovery but is limited by orthostatic intolerance (OI) with a prevalence of 50% 6 h after major surgery. The pathophysiology of postoperative OI is assumed to include hypovolemia besides dysregulation of vasomotor tone. Stroke volume-guided fluid therapy, so-called goal-directed therapy (GDT), corrects functional hypovolemia, and the authors hypothesized that GDT reduces the prevalence of OI after major surgery and assessed this in a prospective, double-blinded trial. METHODS: Forty-two patients scheduled for open radical prostatectomy were randomized into standard fluid therapy (control group) or GDT groups. Both groups received a fixed-volume crystalloid regimen supplemented with 1:1 replacement of blood loss with colloid, and in addition, the GDT group received colloid to obtain a maximal stroke volume (esophageal Doppler). The primary outcome was the prevalence of OI assessed with a standardized mobilization protocol before and 6 h after surgery. Hemodynamic and hormonal orthostatic responses were evaluated. RESULTS: Twelve (57%) versus 15 (71%) patients in the control and GDT groups (P = 0.33), respectively, demonstrated OI after surgery, group difference 14% (CI, -18 to 45%). Patients in the GDT group received more colloid during surgery (1,758 vs. 1,057 ml; P = 0.001) and reached a higher stroke volume (102 vs. 89 ml; P = 0.04). OI patients had an increased length of hospital stay (3 vs. 2 days; P = 0.02) and impaired hemodynamic and norepinephrine responses on mobilization. CONCLUSION: GDT did not reduce the prevalence of OI, and patients with OI demonstrated impaired cardiovascular and hormonal responses to mobilization.

Common syndromes of orthostatic intolerance.

The autonomic nervous system, adequate blood volume, and intact skeletal and respiratory muscle pumps are essential components for rapid cardiovascular adjustments to upright posture (orthostasis). Patients lacking sufficient blood volume or having defective sympathetic adrenergic vasoconstriction develop orthostatic hypotension (OH), prohibiting effective upright activities. OH is one form of orthostatic intolerance (OI) defined by signs, such as hypotension, and symptoms, such as lightheadedness, that occur when upright and are relieved by recumbence. Mild OI is commonly experienced during intercurrent illnesses and when standing up rapidly. The latter is denoted "initial OH" and represents a normal cardiovascular adjustment to the blood volume shifts during standing. Some people experience episodic acute OI, such as postural vasovagal syncope (fainting), or chronic OI, such as postural tachycardia syndrome, which can significantly reduce quality of life. The lifetime incidence of ≥1 fainting episodes is ∼40%. For the most part, these episodes are benign and self-limited, although frequent syncope episodes can be debilitating, and injury may occur from sudden falls. In this article, mechanisms for OI having components of adrenergic hypofunction, adrenergic hyperfunction, hyperpnea, and regional blood volume redistribution are discussed. Therapeutic strategies to cope with OI are proposed.

Predictors of mortality, rehospitalization for syncope, and cardiac syncope in 352 consecutive elderly patients with syncope.

OBJECTIVES: To investigate the etiologies of syncope and predictors of all-cause mortality, rehospitalization, and cardiac syncope in consecutive elderly patients presenting with syncope to our emergency department. PARTICIPANTS: Participants were 352 consecutive patients aged 65 years or older with syncope admitted to hospital from the emergency department. DESIGN: Observational retrospective study. MEASUREMENTS: Review of medical records for history, physical examination, medications, and tests to determine causes of syncope. Cox stepwise logistic regression analysis was performed to identify significant independent prognostic factors for rehospitalization with syncope, all-cause mortality, and cardiac syncope. RESULTS: Of 352 patients, mean age 78 years, the etiology of syncope was diagnosed in 243 patients (69%). Vasovagal syncope was diagnosed in 12%, volume depletion in 14%, orthostatic hypotension in 5%, cardiac syncope in 29%, carotid sinus hypersensitivity in 2%, and drug overdose/others in 7% of patients. During a mean follow-up of 24 months, 10 patients (3%) were readmitted to the hospital for syncope and 39 (11%) died. Stepwise logistic regression analysis identified history of congestive heart failure (OR 5.18; 95% CI 1.23-21.84, P = .0257) and acute coronary syndrome (OR 5.95; 95% CI 1.11-31.79, P = .037) as independent risk factors for rehospitalization. Significant independent prognostic factors for mortality were diabetes mellitus (OR 2.08; 95% CI 1.09-3.99, P = .0263), history of smoking (OR 2.23; 95% CI 1.10-4.49, P = .0255), and use of statins (OR 0.37; 95% CI 0.19-0.72, P = .0036). Independent risk factors for predicting a cardiac cause of syncope were an abnormal electrocardiogram (OR 2.58; 95% CI 1.46-4.57, P = .0012) and reduced ejection fraction (OR 2.92; 95% CI 1.70-5.02, P < .001). The San Francisco Syncope Rule and Osservatorio Epidemiologico sulla Sincope nel Lazio scores did not predict mortality or rehospitalization in our study population. CONCLUSIONS: Significant independent risk factors for rehospitalization for syncope were congestive heart failure and acute coronary syndrome. Significant independent risk factors for mortality were diabetes mellitus, history of smoking, and use of statins (inverse association).

Mechanisms of sympathetic regulation in orthostatic intolerance.

Sympathetic circulatory control is key to the rapid cardiovascular adjustments that occur within seconds of standing upright (orthostasis) and which are required for bipedal stance. Indeed, patients with ineffective sympathetic adrenergic vasoconstriction rapidly develop orthostatic hypotension, prohibiting effective upright activities. One speaks of orthostatic intolerance (OI) when signs, such as hypotension, and symptoms, such as lightheadedness, occur when upright and are relieved by recumbence. The experience of transient mild OI is part of daily life. However, many people experience episodic acute OI as postural faint or chronic OI in the form of orthostatic tachycardia and orthostatic hypotension that significantly reduce the quality of life. Potential mechanisms for OI are discussed including forms of sympathetic hypofunction, forms of sympathetic hyperfunction, and OI that results from regional blood volume redistribution attributable to regional adrenergic hypofunction.

Neurocardiogenic syncope coexisting with postural orthostatic tachycardia syndrome in patients suffering from orthostatic intolerance: a combined form of autonomic dysfunction.

INTRODUCTION: There is anecdotal evidence that one or more forms of orthostatic intolerance (OI) subgroups may coexist in the same patients. However, there is a paucity of published data on the clinical features and management of patients who suffer from coexisting features of postural tachycardia syndrome (POTS) and neurocardiogenic syncope (NCS). We herein present our experience of 18 patients who we found displayed evidence of coexisting NCS and POTS. METHODS: We reviewed charts of 300 POTS patients seen at the University of Toledo Syncope and Autonomic Disorders Center from 2003 to 2010 and found 18 patients eligible for inclusion in this study. Patients were included in this study if they reported clinical symptoms consistent with both POTS and NCS and then demonstrated a typical POTS pattern (a rise in heart rate without change in blood pressure [BP]) on head up tilt table (HUTT) within the first 10 minutes of upright posture followed by a neurocardiogenic pattern (a sudden fall in heart rate and/or fall in blood pressure) reproducing symptoms that were similar to the patients spontaneous episodes. RESULTS: We found 18 patients, mean age (30 ± 12), with 15 (84%) women and three (16%) men, who met the inclusion criterion for this study. Each of these 18 patients demonstrated a typical POTS pattern within the first 10 minutes on initial physical exam and on a HUTT. Continued tilting beyond 10 minutes resulted in a sudden decline in heart rate (which in some patients manifested as an asystole that lasted anywhere between 10 and 32 seconds [mean of 18 seconds]) and/or a fall in BP in each of these patients demonstrating a pattern consistent with neurocardiogenic subtype of OI. The mean time to the NCS pattern of a fall in BP and heart was 15 minutes with a range of 13-20 minutes. This group of patients was highly symptomatic and reported frequent clinical symptoms that were suggestive of OI. Recurrent presyncope, syncope, orthostatic palpitations, exercise intolerance, and fatigue were the principal symptoms reported. CONCLUSION: NCS may coexist with POTS in a subgroup of patients suffering from OI.