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Neurosurgery Clinics of North America Jan 2023Individuals with Chiari malformation can present with symptoms of fatigue, lightheadedness, and syncope-the cardinal features of orthostatic intolerance. Similar... (Review)
Review
Individuals with Chiari malformation can present with symptoms of fatigue, lightheadedness, and syncope-the cardinal features of orthostatic intolerance. Similar orthostatic symptoms can complicate the clinical course following Chiari decompression. The presence of orthostatic intolerance in patients with Chiari malformation is not surprising given the location of the major circulatory control centers and their pathways in the brainstem. This article reviews the normal physiologic response to upright posture and the common forms of orthostatic intolerance encountered in clinical practice. The authors describe the relationship between orthostatic intolerance and Chiari malformation and provide suggestions regarding the evaluation and management of these disorders.
Topics: Humans; Orthostatic Intolerance; Hypotension, Orthostatic; Arnold-Chiari Malformation
PubMed: 36424063
DOI: 10.1016/j.nec.2022.09.002 -
European Journal of Applied Physiology Sep 2022Despite several studies that have been investigated physical inactivity and age-related effects on orthostatic tolerance, impaired hemodynamics and postural balance... (Review)
Review
Despite several studies that have been investigated physical inactivity and age-related effects on orthostatic tolerance, impaired hemodynamics and postural balance responses to orthostatic stress are incorrectly attributed to aging or sedentarism alone. The isolated effects from aging and sedentarism should be investigated through comparative studies between senior athletes and age-matched controls, and physical activity assessments on aging follow-up studies. On the other hand, bed rest and space flight studies mimic accelerated physical inactivity or disuse, which is not the same physiological decline provoked by aging alone. Thus, the elementary question is: could orthostatic intolerance be attributed to aging or physical inactivity? The main purpose of this review is to provide an overview of possible mechanisms underlying orthostatic tolerance contrasting the paradigm of aging and/or physical inactivity. The key points of this review are the following: (1) to counterpoint all relevant literature on physiological aspects of orthostatic tolerance; (2) to explore the mechanistic aspects underneath the cerebrovascular, cardiorespiratory, and postural determinants of orthostatic tolerance; and (3) examine non-pharmacological interventions with the potential to counterbalance the physical inactivity and aging effects. To date, the orthostatic intolerance cannot be attributed exclusively with aging since physical inactivity plays an important role in postural balance, neurovascular and cardiorespiratory responses to orthostatic stress. These physiological determinates should be interpreted within an integrative approach of orthostatic tolerance, that considers the interdependence between physiological systems in a closed-loop model. Based on this multisystem approach, acute and chronic countermeasures may combat aging and sedentarism effects on orthostatic tolerance.
Topics: Aging; Bed Rest; Hemodynamics; Humans; Orthostatic Intolerance; Postural Balance
PubMed: 35716190
DOI: 10.1007/s00421-022-04978-4 -
Progress in Cardiovascular Diseases 2020Although diagnostic criteria have been developed characterizing postural orthostatic tachycardia syndrome (POTS), no single set of criteria is universally accepted.... (Review)
Review
Although diagnostic criteria have been developed characterizing postural orthostatic tachycardia syndrome (POTS), no single set of criteria is universally accepted. Furthermore, there are gaps in the present criteria used to identify individuals who have this condition. The reproducibility of the physiological findings, the relationship of symptoms to physiological findings, the presence of symptoms alone without any physiological findings and the response to various interventions confuse rather than clarify this condition. As many disease entities can be confused with POTS, it becomes critical to identify what this syndrome is. What appears to be POTS may be an underlying condition that requires specific therapy. POTS is not simply orthostatic intolerance and symptoms or intermittent orthostatic tachycardia but the syndrome needs to be characterized over time and with reproducibility. Here we address critical issues regarding the pathophysiology and diagnosis of POTS in an attempt to arrive at a rational approach to categorize the syndrome with the hope that it may help both better identify individuals and better understand approaches to therapy.
Topics: Blood Pressure; Diagnosis, Differential; Heart Rate; Humans; Postural Orthostatic Tachycardia Syndrome; Posture; Predictive Value of Tests; Prognosis; Reproducibility of Results
PubMed: 32222376
DOI: 10.1016/j.pcad.2020.03.010 -
Obesity Surgery May 2021Predisposing factors of new-onset orthostatic intolerance (OI) after bariatric surgery (BS) are unknown. The purpose of this study is to summarize current existing data... (Review)
Review
Predisposing factors of new-onset orthostatic intolerance (OI) after bariatric surgery (BS) are unknown. The purpose of this study is to summarize current existing data on new-onset OI after BS. Materials and methods were considered for a search of articles that were published by the 30 of July 2020. A systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and in line with the protocol agreed by all authors was conducted. Of the 604 initially identified articles, four studies were found to match the established criteria and were extracted for eligibility. 83.3% were female. Hypertension, type 2 diabetes mellitus, and obstructive sleep apnea syndrome were the most frequently reported comorbidities. Surgical intervention such as revision, conversion, or reversal was not documented in these studies. Awareness of this issue must be raised due to the possibility of reduced quality of life and the risk of syncope.
Topics: Bariatric Surgery; Diabetes Mellitus, Type 2; Female; Humans; Male; Obesity, Morbid; Orthostatic Intolerance; Quality of Life
PubMed: 33655427
DOI: 10.1007/s11695-021-05266-4 -
Neuroscience Bulletin Feb 2019
Review
Topics: Blood Coagulation Disorders; Blood Pressure; Hemodynamics; Humans; Orthostatic Intolerance; Platelet Count; Posture
PubMed: 30315398
DOI: 10.1007/s12264-018-0295-6 -
Annual Review of Medicine Jan 2020Postural orthostatic tachycardia syndrome (POTS) is a clinically heterogeneous disorder with multiple contributing pathophysiologic mechanisms manifesting as symptoms of... (Review)
Review
Postural orthostatic tachycardia syndrome (POTS) is a clinically heterogeneous disorder with multiple contributing pathophysiologic mechanisms manifesting as symptoms of orthostatic intolerance in the setting of orthostatic tachycardia (increase in heart rate by at least 30 beats per minute upon assuming an upright position) without orthostatic hypotension. The three major pathophysiologic mechanisms include partial autonomic neuropathy, hypovolemia, and hyperadrenergic state. Patients often will exhibit overlapping characteristics from more than one of these mechanisms. The approach to the treatment of POTS centers on treating the underlying pathophysiologic mechanism. Stockings, abdominal binders, and vasoconstrictors are used to enhance venous return in partial neuropathic POTS. Exercise and volume expansion are the main treatment strategies for hypo-volemic POTS. For hyperadrenergic POTS, beta-blockers and avoidance of norepinephrine reuptake inhibitors is important. Attempts should be made to discern which pathophysiologic mechanism(s) may be afflicting patients so that treatment regimens can be individualized.
Topics: Adrenergic beta-Antagonists; Cardiovascular Agents; Clonidine; Combined Modality Therapy; Female; Humans; Ivabradine; Male; Methyldopa; Postural Orthostatic Tachycardia Syndrome; Quality of Life; Risk Assessment; Severity of Illness Index; Survival Analysis; Treatment Outcome
PubMed: 31412221
DOI: 10.1146/annurev-med-041818-011630 -
Journal of the American College of... Mar 2019Postural orthostatic tachycardia syndrome (POTS), the most common form of orthostatic intolerance in young people, affects approximately 500,000 people in the United... (Review)
Review
Postural orthostatic tachycardia syndrome (POTS), the most common form of orthostatic intolerance in young people, affects approximately 500,000 people in the United States alone, typically young women at the peak of their education and the beginning of their working lives. This is a heterogeneous disorder, the pathophysiology and mechanisms of which are not well understood. There are multiple contributing factors and numerous potential mimics. This review details the most current views on the potential causes, comorbid conditions, proposed subtypes, differential diagnoses, evaluations, and treatment of POTS from cardiological and neurological perspectives.
Topics: Causality; Comorbidity; Diagnosis, Differential; Humans; Patient Care Management; Postural Orthostatic Tachycardia Syndrome
PubMed: 30871704
DOI: 10.1016/j.jacc.2018.11.059 -
The Physician and Sportsmedicine Oct 2022Orthostatic intolerance (OI) following pediatric concussion is not well understood. Assessing the prevalence of concussion-related OI and how it compares to...
Orthostatic intolerance (OI) following pediatric concussion is not well understood. Assessing the prevalence of concussion-related OI and how it compares to non-concussion-related OI will improve care for patients suffering with these symptoms. OBJECTIVE: We set out to describe concussion-related OI in adolescence, with particular emphasis on time to recovery and differences from non-concussion-related OI (including male vs. female prevalence). Retrospective chart reviews were completed on post-concussion patients endorsing symptoms of OI. The patients' sex, sport history, previous concussions, time since injury, and recovery time were analyzed and compared between males and females as well as against general OI statistics. Thirty-nine pediatric patients, representing 8.7% of all new patients referred to a specialized concussion clinic over a 13-month interval, were included in the chart review. Mean age of onset was 15.0 ± 2.5 years and 18 (46%) were males. The median times from evaluation to symptom resolution were 120 days. Of 18 patients who completed head-up tilt table testing, 17 (94%) had orthostatic tachycardic response (>40 bpm heart rate increment). Post-concussive OI differs from other orthostatic intolerance etiologies, lacking a strong female predominance and exhibiting a shorter time course to recovery compared to other etiologies of OI (but longer recovery time compared to concussion patients in general). Clinical orthostatic vital signs may not be sensitive for diagnosing orthostatic intolerance in athletes, likely due to higher vagal tone and more efficient skeletal muscle pump.
Topics: Adolescent; Brain Concussion; Child; Female; Heart Rate; Humans; Male; Orthostatic Intolerance; Retrospective Studies; Tilt-Table Test
PubMed: 34236936
DOI: 10.1080/00913847.2021.1953357 -
Herzschrittmachertherapie &... Jun 2018Orthostatic intolerance is characterized by symptoms of light-headedness or syncope that is provoked upon standing or in an upright posture. It is most commonly caused... (Review)
Review
Orthostatic intolerance is characterized by symptoms of light-headedness or syncope that is provoked upon standing or in an upright posture. It is most commonly caused by postural orthostatic tachycardia syndrome (POTS) or orthostatic hypotension (OH). Its pathophysiology is complex and commonly involves abnormal autonomic nervous system regulation, autoimmunity, a hyperadrenergic state, and hypovolemia. This article reviews the pathophysiology underlying orthostatic intolerance, as well as the current treatment available.
Topics: Humans; Hypotension, Orthostatic; Orthostatic Intolerance; Postural Orthostatic Tachycardia Syndrome; Posture; Tachycardia
PubMed: 29696346
DOI: 10.1007/s00399-018-0563-1 -
Journal of Internal Medicine Apr 2019Postural orthostatic tachycardia syndrome (POTS) is a variant of cardiovascular autonomic disorder characterized by an excessive heart rate increase on standing and... (Review)
Review
Postural orthostatic tachycardia syndrome (POTS) is a variant of cardiovascular autonomic disorder characterized by an excessive heart rate increase on standing and orthostatic intolerance. POTS affects younger individuals 15-45 years old with a distinct female predominance (≈80%). The prevalence ranges between 0.2% and 1.0% in developed countries. The onset of POTS is typically precipitated by immunological stressors such as viral infection, vaccination, trauma, pregnancy, surgery or psychosocial stress. The most common complaints are dizziness, weakness, rapid heartbeat and palpitation on standing. Moreover, patients often report physical deconditioning and reduced exercise capacity as well as headache, 'brain fog', dyspnoea, gastrointestinal disorders and musculoskeletal pain. The aetiology of POTS is largely unknown and three main hypotheses include an autoimmune disorder, abnormally increased sympathetic activity and catecholamine excess, and sympathetic denervation leading to central hypovolaemia and reflex tachycardia. The golden standard for POTS diagnosis is head-up tilt test with a non-invasive beat-to-beat haemodynamic monitoring. Although long-term prognosis of POTS is poorly explored, around 50% of patients spontaneously recover within 1-3 years. After the diagnosis has been established, patient should be thoroughly educated about non-pharmacological measures alleviating the symptoms. Exercise training may be very effective and counteract deconditioning. In more symptomatic patients, different drugs directed at controlling heart rate, increasing peripheral vasoconstriction and intravascular volume can be tested. However, the overall effects of pharmacological therapy are modest and the most affected patients remain handicapped. Future efforts should focus on better understanding of POTS pathophysiology and designing randomized controlled trials for selection of more effective therapy.
Topics: Cardiovascular System; Humans; Postural Orthostatic Tachycardia Syndrome
PubMed: 30372565
DOI: 10.1111/joim.12852