Postural orthostatic tachycardia syndrome

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Postural orthostatic tachycardia syndrome (POTS) is a condition characterized by an abnormally large increase in heart rate upon sitting up or standing.<ref name="pmid23122672">Template:Cite journal</ref> POTS in adults is characterized by a heart rate increase of 30 beats per minute within ten minutes of standing up, accompanied by other symptoms.<ref name="pmid23122672" /> This increased heart rate should occur in the absence of orthostatic hypotension (>20 mm Hg drop in systolic blood pressure)<ref name="pmid25980576">Template:Cite journal</ref> to be considered POTS. POTS is a disorder of the autonomic nervous system that can lead to a variety of symptoms, including lightheadedness, brain fog, blurred vision, weakness, fatigue, headaches, heart palpitations, exercise intolerance, nausea, difficulty concentrating, tremulousness (shaking), syncope (fainting), coldness, pain or numbness in the extremities, chest pain, and shortness of breath.<ref name="pmid23122672" /><ref name="pmid32528589">Template:Cite journal</ref><ref name="pmid23999934">Template:Cite journal</ref><ref name="pmid34144933" /> Many symptoms are worsened with postural changes, especially standing up. POTS symptoms may be treated with lifestyle changes such as increasing fluid, electrolyte, and salt intake, wearing compression stockings, slowing down postural changes, exercise, medication, and physical therapy.

The causes of POTS are varied.<ref name="Ferri_2017">Template:Cite book</ref> In some cases, it develops after a viral infection, surgery, trauma, autoimmune disease, or pregnancy.<ref name="pmid18506020">Template:Cite journal</ref> It has also been shown to emerge in previously healthy patients after contracting COVID-19,<ref name="pmid33740207">Template:Cite journal</ref><ref name="pmid33786700">Template:Cite journal</ref><ref>Template:Cite journal</ref> in people with Long COVID (post-COVID-19 condition),<ref>Template:Cite journal</ref> or possibly in rare cases after COVID-19 vaccination, though causative evidence is limited and further study is needed.<ref name="Blitshteyn_2022">Template:Cite journal</ref> POTS is more common among people who got infected with SARS-CoV-2 than among those who got vaccinated against COVID-19.<ref name="pmid38000119">Template:Cite journal</ref> About 30% of severely infected patients with long COVID have POTS. Risk factors include a family history of the condition.<ref name="pmid23122672" />

Treatment may include:

Medications used may include:

More than 50% of patients whose condition was triggered by a viral infection get better within five years.<ref name="pmid18506020" /> About 80% of patients have symptomatic improvement with treatment, while 25% are so disabled they are unable to work.<ref name="Busmer_2011" /><ref name="pmid18506020" /> A retrospective study on patients with adolescent-onset has shown that five years after diagnosis, 19% of patients had full resolution of symptoms.<ref name="pmid26979650">Template:Cite journal</ref>

It is estimated that 1–3 million people in the United States have POTS.<ref name="Johns Hopkins Medicine-2022">Template:Cite news</ref> The average age for POTS onset is 20, and it occurs about five times more frequently in females than in males.<ref name="pmid23122672" />

Signs and symptoms

Person standing and measuring heart rate with a pulse oximeter which shows tachycardia of 108 bpm

POTS is a complex and multifaceted clinical disorder, the etiology and management of which remain incompletely understood. This syndrome is typified by a diverse array of nonspecific symptoms, making it a challenging condition to describe.<ref name="pmid38465412">Template:Cite journal</ref>

Individuals living with POTS experience a diminished quality of life compared to healthy individuals, due to disruptions in various domains such as standing, playing sports, symptom anxiety, and impacts on school, work, or spiritual (religious) domains—these disruptions affect their daily life and overall well-being.<ref name="pmid38364354">Template:Cite journal</ref>

In adults, the primary manifestation is an increase in heart rate of more than 30 beats per minute within ten minutes of standing up.<ref name="pmid23122672"/><ref name="pmid24982638">Template:Cite journal</ref> The resulting heart rate is typically more than 120 beats per minute.<ref name="pmid23122672"/> For people between the ages of 12 and 19, the minimum increase for a POTS diagnosis is 40 beats per minute.<ref name="Freeman_2011" />

POTS is often accompanied by common features of orthostatic intolerance—in which symptoms that develop while upright are relieved by reclining.<ref name="pmid24982638" /> These orthostatic symptoms include palpitations, light-headedness, chest discomfort, shortness of breath,<ref name="pmid24982638" /> nausea, weakness or "heaviness" in the lower legs, blurred vision, and cognitive difficulties.<ref name="pmid23122672" /> Symptoms may be exacerbated with prolonged sitting, prolonged standing, alcohol, heat, exercise, or eating a large meal.<ref name="pmid38401460">Template:Cite journal</ref>

Up to one-third of POTS patients experience fainting for many reasons, including but not limited to standing, physical exertion, or heat exposure.<ref name="pmid23122672" /> POTS patients may also experience orthostatic headaches.<ref name="pmid20819844">Template:Cite journal</ref> Some POTS patients may develop blood pooling in the extremities, characterized by a reddish-purple color of the legs and/or hands upon standing.<ref name="pmid12010910">Template:Cite journal</ref><ref name="Abou-Diab-2018">Template:Cite journal</ref><ref name="Mathias_2012" /><ref name="pmid16943900" /> 48% of people with POTS report chronic fatigue and 32% report sleep disturbances.<ref name="pmid25071706">Template:Cite journal</ref><ref name="pmid21509337">Template:Cite journal</ref><ref name="pmid38364354"/><ref name="Haensch-2012">Template:Cite journal</ref><ref name="pmid28442939">Template:Cite journal</ref> Other POTS patients only exhibit the cardinal symptom of orthostatic tachycardia.<ref name="Mathias_2012" />

POTS and dysautonomia sometimes present with narrowed pulse pressures. In such cases, patients experience a drop in pulse pressure to 0 mm Hg upon standing, rendering them practically pulseless while upright. This condition leads to significant morbidity, as many affected individuals struggle to stand at all.<ref name="pmid29494015">Template:Citation</ref>

Additional signs and symptoms are varied, and may include excessive sweating, lack of sweating, heat intolerance, digestive issues such as nausea, indigestion, bloating, constipation or diarrhea, post-exertional malaise, coat-hanger pain, brain fog, and syncope or presyncope.<ref name="Cleveland-Clinic-2021-Symptoms">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Whereas POTS is primarily characterized by its impact on the autonomic and cardiovascular systems, it can lead to substantial functional impairment. This impairment, often manifesting as symptoms such as fatigue, cognitive dysfunction, and sleep disturbances, can significantly diminish the patient's quality of life.<ref name="pmid38364354"/>

Brain fog

One of the most disabling and prevalent symptoms in POTS is "brain fog",<ref name="pmid32528589" /> a term used by patients to describe the cognitive difficulties they experience. In one survey of 138 POTS patients, brain fog was defined as "forgetful" (91%), "difficulty thinking" (89%), and "difficulty focusing" (88%). Other common descriptions were "difficulty processing what others say" (80%), "confusion" (71%), "getting lost" (64%), and "thoughts moving too quickly" (40%).<ref name="pmid23999934" /> The same survey described the most common triggers of brain fog to be fatigue (91%), lack of sleep (90%), prolonged standing (87%), and dehydration (86%).<ref name="pmid23999934" />

Neuropsychological testing has shown that a POTS patient has reduced attention (Ruff 2&7 speed and WAIS-III digits forward), short-term memory (WAIS-III digits back), cognitive processing speed (symbol digits modalities test), and executive function (Stroop word color and trails B).<ref name="pmid29628432">Template:Cite journal</ref><ref name="pmid25001527">Template:Cite journal</ref><ref name="pmid25009504">Template:Cite journal</ref>

A potential cause for brain fog is a decrease in cerebral blood flow (CBF), especially in the upright position.<ref name="pmid10037116">Template:Cite journal</ref><ref name="pmid27525257">Template:Cite journal</ref><ref name="pmid19502561">Template:Cite journal</ref>

There may be a loss of neurovascular coupling and reduced functional hyperemia in response to cognitive challenge under orthostatic stress, perhaps related to a loss of autoregulatory buffering of beat-by-beat fluctuations in arterial blood flow.<ref name="pmid25510829">Template:Cite journal</ref>

Comorbidities

Conditions that are commonly reported with POTS include:<ref name="pmid34144933">Template:Cite journal</ref><ref name="pmid35288409">Template:Cite journal</ref>

There are some overlaps between POTS and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), with evidence of POTS in 10–20% of ME/CFS cases.<ref name="Dipaola_2020">Template:Cite journal</ref><ref name="pmid19088364" /> Fatigue and reduced exercise tolerance are prominent symptoms of both conditions, and dysautonomia may underlie both conditions.<ref name="pmid19088364" />

Causes

The pathophysiology of POTS is not attributable to a single cause or unified hypothesis—it is the result of multiple interacting mechanisms, each contributing to the overall clinical presentation; the mechanisms may include autonomic dysfunction, hypovolemia, deconditioning, hyperadrenergic states, etc.<ref name="pmid38465412"/>

The symptoms of POTS can be caused by several distinct pathophysiological mechanisms.<ref name="pmid24982638"/> These mechanisms are poorly understood,<ref name="Freeman_2011" /> and can overlap, with many patients showing features of multiple POTS types.<ref name="pmid24982638"/> Many people with POTS exhibit low blood volume (hypovolemia), which can decrease the rate of blood flow to the heart.<ref name="pmid24982638"/> To compensate for low blood volume, the heart increases its cardiac output by beating faster (reflex tachycardia),<ref name="pmid20117742" /> leading to the symptoms of presyncope.

In the 30% to 60% of cases classified as hyperadrenergic POTS, norepinephrine levels are elevated on standing,<ref name="pmid23122672"/> often due to hypovolemia or partial autonomic neuropathy.<ref name="pmid24982638"/> A smaller minority of people with POTS have (typically very high) standing norepinephrine levels that are elevated even in the absence of hypovolemia and autonomic neuropathy; this is classified as central hyperadrenergic POTS.<ref name="pmid24982638"/><ref name="pmid16943900" /> The high norepinephrine levels contribute to symptoms of tachycardia.<ref name="pmid24982638"/>

Another subtype, neuropathic POTS, is associated with denervation of sympathetic nerves in the lower limbs.<ref name="pmid24982638" /> In this subtype, it is thought that impaired constriction of the blood vessels causes blood to pool in the veins of the lower limbs.<ref name="pmid23122672" /> Heart rate increases to compensate for this blood pooling.<ref name="pmid22687203">Template:Cite journal</ref>

A subset of POTS patients have markedly reduced myocardial MIBG reuptake via MIBG myocardial scintigraphy,<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> interpreted to be a potential manifestation of autonomic cardiac neuropathy, although reduced expression of the norepinephrine transporter may also result in impaired MIBG reuptake and has been implicated in POTS.<ref>Template:Cite journal</ref>

In up to 50% of cases, symptom onset followed a viral illness.<ref name="pmid21947988" /> It may also be linked to physical trauma, concussion, pregnancy, surgery, menarche, or psychosocial stress.<ref name="pmid29909990" /><ref name="pmid30372565" /><ref name="Mathias_2012" /> It is believed that these events could act as a trigger for an autoimmune response that result in POTS.<ref name="Wilson-2015">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> It has been shown to emerge in previously healthy patients after COVID-19,<ref name="Mallick_2023">Template:Cite journal</ref><ref name="pmid33740207" /><ref name="pmid33786700"/> or after COVID-19 vaccination.<ref name = "Blitshteyn_2022" /> A 2023 review found that the chances of being diagnosed with POTS within 90 days after mRNA vaccination were 1.33 times higher compared to 90 days before vaccination. Still, the results are inconclusive due to a small sample size; only 12 cases of newly diagnosed POTS after mRNA vaccination were reported, all these 12 patients having autoimmune antibodies. However, the risk of POTS-related diagnoses was 5.35 times higher after getting infected with SARS-CoV-2 compared to after mRNA vaccination.<ref name="pmid37654428">Template:Cite journal</ref> Possible mechanisms for COVID-induced POTS are hypovolemia, autoimmunity/inflammation from antibody production against autonomic nerve fibers, and direct toxic effects of COVID-19, or secondary sympathetic nervous system stimulation.<ref name="Mallick_2023" />

POTS is more common in females than males with up to 94% of patients being female. POTS also has been linked to patients with a history of autoimmune diseases,<ref name="pmid29909990">Template:Cite journal</ref> long Covid,<ref name="pmid36639608">Template:Cite journal</ref><ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> irritable bowel syndrome, anemia, hyperthyroidism, fibromyalgia, diabetes, amyloidosis, sarcoidosis, systemic lupus erythematosus, and cancer. Genetics likely plays a role, with one study finding that one in eight POTS patients reported a history of orthostatic intolerance in their family.<ref name="pmid20117742" />

Physical deconditioning may be a factor involved in POTS.<ref name="JoynerMasuki2008">Template:Cite journal</ref><ref name="Joyner2012">Template:Cite journal</ref> Strong parallels have been found between POTS and strong physical deconditioning or people who have undergone prolonged periods of bed rest.<ref name="JoynerMasuki2008" /><ref name="Joyner2012" /> Both POTS and deconditioning are marked by cardiac atrophy, reduced blood volume, and other physical changes.<ref name="JoynerMasuki2008" /><ref name="Joyner2012" /> There are also similarities between POTS and deconditioning in response to exercise.<ref name="JoynerMasuki2008" /><ref name="Joyner2012" /> There are however distinct differences between classic cardiovascular deconditioning and POTS in most cases.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref>

Autoimmunity

There is an increasing number of studies indicating that POTS is an autoimmune disease.<ref name="pmid29909990" /><ref name="pmid27702852" /><ref name="pmid26846691">Template:Cite journal</ref><ref name="Miller_2019" /><ref name="pmid31547749">Template:Cite journal</ref><ref name="pmid31938977">Template:Cite journal</ref> A high number of patients has elevated levels of autoantibodies against the α1-adrenergic receptor and against the muscarinic acetylcholine M4 receptor.<ref name="pmid32750291">Template:Cite journal</ref><ref name="Gunning_2019" /><ref name="pmid33562074">Template:Cite journal</ref>

Elevations of autoantibodies targeting the α1-adrenergic receptor have been associated with symptom severity in patients with POTS.<ref name="pmid32750291" />

More recently, autoantibodies against other targets have been identified in small cohorts of POTS patients.<ref name="pmid29618472">Template:Cite journal</ref> Signs of innate immune system activation with elaboration of pro-inflammatory cytokines has also been reported in a cohort of POTS patients.<ref name="pmid33562074"/> Studies suggest the involvement of adrenergic, cholinergic, and angiotensin II type I autoantibodies in the pathogenesis of orthostatic intolerance, so that these autoantibodies are thought to interfere with the normal functioning of the autonomic nervous system, leading to the symptoms observed in POTS; as such, there is growing interest in the use of immunomodulation therapy as a potential treatment strategy for POTS: immunomodulation therapy aims to regulate or normalize the immune response, thereby reducing the production of harmful autoantibodies.<ref name="pmid38673062">Template:Cite journal</ref>

Secondary POTS

If POTS is caused by another condition, it may be classified as secondary POTS.<ref name="pmid18506020" /> Common causes of secondary POTS are chronic diabetes mellitus,<ref name="pmid18506020" /> autoimmune disorders like multiple sclerosis, lupus, and Sjögren syndrome, connective tissue disorders like Ehlers-Danlos syndrome and marfan syndrome and post viral syndromes caused by diseases like Epstein-Barr or Covid-19.

A trifecta of POTS, Ehlers-Danlos syndrome (EDS), and mast cell activation syndrome (MCAS) is becoming increasingly more common, with a genetic marker common among all three conditions.<ref name="pmid30007466">Template:Cite journal</ref><ref name="Cheung-2015">Template:Cite journal</ref><ref name="pmid31267471">Template:Cite journal</ref><ref name="Chang-2019">Template:Cite journal</ref> With Mast cell activation syndrome (MCAS), it is not yet clear whether MCAS is a secondary cause of POTS or simply comorbid; however, treating MCAS for these patients can significantly improve POTS symptoms.<ref name="pmid23753844" />

POTS can sometimes be a paraneoplastic syndrome associated with cancer.<ref name="pmid19506133">Template:Cite journal</ref>

There have also been reports of patients experiencing co-occurring POTS, May-Thurner Syndrome, and EDS.<ref name=":0">Template:Cite journal</ref>

Diagnosis

Results of a tilt table test positive for POTS

POTS is a complex disorder with a multifactorial etiology, and the diagnosis of POTS is challenging.<ref name="pmid38465412"/>

POTS is most commonly diagnosed by a cardiologist (41%), cardiac electrophysiologist (15%), or neurologist (19%).<ref name="pmid30861229">Template:Cite journal</ref> The average number of physicians seen before receiving diagnosis is seven, and the average delay before diagnosis is 4.7 years.<ref name="pmid30861229" />

Diagnostic criteria

A POTS diagnosis requires the following characteristics:<ref name="pmid34144933"/>

  • For patients age 20 or older, a sustained increase in heart rate ≥30 bpm within ten minutes of upright posture (tilt table test or standing) from a supine position.
    • For patients age 12–19, the heart rate increase must be >40 bpm.
  • Associated with frequent symptoms of lightheadedness, palpitations, tremulousness, generalized weakness, blurred vision, or fatigue that are worse with upright posture and that improve with recumbence.
  • An absence of orthostatic hypotension (i.e., no sustained systolic blood pressure drop of 20 mmHg or more).
  • Chronic symptoms that have lasted for longer than three months.
  • Other disorders, medications, or functional states that are known to predispose to orthostatic tachycardia such as a spinal fluid leak (called spontaneous intracranial hypotension),<ref name="Graf-2018">Template:Cite journal</ref> dehydration, orthostatic hypotension, heart problems, adrenal insufficiency, epilepsy, and Parkinson's disease must not be present.<ref name="pmid27578452">Template:Cite journal</ref>

Alternative tests to the tilt table test are also used, such as the NASA Lean Test<ref name="pmid32799889">Template:Cite journal</ref> and the adapted Autonomic Profile (aAP)<ref name="Sivan-2022">Template:Cite journal</ref> which require less equipment to complete. Nonpostural testing, such as the Valsalva maneuver, which may minimize the triggering of POTS symptoms, can be used prior to or in conjunction with the aforementioned techniques as a potential indicator of orthostatic intolerance, including POTS.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref>

Orthostatic intolerance

An increase in heart rate upon moving to an upright posture is known as orthostatic (upright) tachycardia (fast heart rate). It occurs without any coinciding drop in blood pressure, as that would indicate orthostatic hypotension.<ref name="pmid24982638" /> Certain medications to treat POTS may cause orthostatic hypotension. It is accompanied by other features of orthostatic intolerance—symptoms that develop in an upright position and are relieved by reclining.<ref name="pmid24982638" /> These orthostatic symptoms include palpitations, light-headedness, chest discomfort, shortness of breath,<ref name="pmid24982638" /> nausea, weakness or "heaviness" in the lower legs, blurred vision, and cognitive difficulties.<ref name="pmid23122672" />

Differential diagnoses

A variety of autonomic tests are employed to exclude autonomic disorders that could underlie symptoms, while endocrine testing is used to exclude hyperthyroidism and rarer endocrine conditions.<ref name="Mathias_2012" /> Electrocardiography is normally performed on all patients to exclude other possible causes of tachycardia.<ref name="pmid23122672" /><ref name="Mathias_2012" /> In cases where a particular associated condition or complicating factor are suspected, other non-autonomic tests may be used: echocardiography to exclude mitral valve prolapse, and thermal threshold tests for small-fiber neuropathy.<ref name="Mathias_2012" />

Testing the cardiovascular response to prolonged head-up tilting, exercise, eating, and heat stress may help determine the best strategy for managing symptoms.<ref name="Mathias_2012" /><ref name="pmid38401460"/> POTS has also been divided into several types (see § Causes), which may benefit from distinct treatments.<ref name="pmid19207771" /> People with neuropathic POTS show a loss of sweating in the feet during sweat tests, as well as impaired norepinephrine release in the leg,<ref name="Giris_1999">Template:Cite journal</ref> but not arm.<ref name="pmid23122672"/><ref name="pmid19207771" /><ref name="pmid11018167">Template:Cite journal</ref> This is believed to reflect peripheral sympathetic denervation in the lower limbs.<ref name="Giris_1999" /><ref name="pmid25120493">Template:Cite journal</ref><ref name="pmid23122672"/> People with hyperadrenergic POTS show a marked increase of blood pressure and norepinephrine levels when standing, and are more likely to have from prominent palpitations, anxiety, and tachycardia.<ref name="pmid24862636">Template:Cite journal</ref><ref name="pmid26386646">Template:Cite journal</ref><ref name="pmid21947988">Template:Cite journal</ref><ref name="pmid19207771" />

People with POTS can be misdiagnosed with inappropriate sinus tachycardia (IST) as they present similarly. One distinguishing feature is that those with POTS rarely exhibit >100 bpm while in a supine position, while patients with IST often have a resting heart rate >100 bpm. Additionally, patients with POTS display a more pronounced change in heart rate in response to postural change.<ref name="pmid18506020" />

Treatment

Despite numerous therapeutic interventions proposed for the management of POTS, none have received approval from the U.S. Food and Drug Administration (FDA) specifically for this indication, and no effective treatment strategies have been identified that would have been confirmed by large clinical trials.<ref name="pmid38465412"/>

POTS treatment involves using multiple methods in combination to counteract cardiovascular dysfunction, address symptoms, and simultaneously address any associated disorders.<ref name="Mathias_2012" /><ref name="pmid38465412"/> For most patients, water intake should be increased, especially after waking, to expand blood volume (reducing hypovolemia).<ref name="Mathias_2012" /><ref name="pmid38465412"/> Eight to ten cups of water daily are recommended.<ref name="pmid23753844" /> Increasing salt intake, by adding salt to food, taking salt tablets, or drinking sports drinks and other electrolyte solutions, is an effective way to raise blood pressure by helping the body retain water. Different physicians recommend different amounts of sodium to their patients.<ref name="Grubb_2006">Template:Cite journal</ref> Combining these techniques with gradual physical training enhances their effect.<ref name="Mathias_2012" /><ref name="pmid38465412"/> In some cases, when increasing oral fluids and salt intake is not enough, intravenous saline or the drug desmopressin is used to help increase fluid retention.<ref name="Mathias_2012" /><ref name="pmid16943900">Template:Cite journal</ref>

Large meals worsen symptoms for some people. These people may benefit from eating small meals frequently throughout the day instead.<ref name="Mathias_2012" /> Alcohol and food high in carbohydrates can also exacerbate symptoms of orthostatic hypotension.<ref name="Freeman_2011">Template:Cite journal</ref> Excessive consumption of caffeine beverages should be avoided, because they can promote urine production (leading to fluid loss) and consequently hypovolemia.<ref name="Mathias_2012" /> Exposure to extreme heat may also aggravate symptoms.<ref name="pmid23753844" />

Prolonged physical inactivity can worsen the symptoms of POTS.<ref name="Mathias_2012" /><ref name="JoynerMasuki2008" /> POTS may be caused or exacerbated by deconditioning.<ref name="JoynerMasuki2008" /><ref name="FuLevine2018">Template:Cite journal</ref> Techniques that increase a person's capacity for exercise, such as endurance training or graded exercise therapy, can relieve symptoms for some patients.<ref name="Mathias_2012" /><ref name="JoynerMasuki2008" /> Exercise programs may be very effective and can lead to symptom improvement in some people with POTS, but should not be used for patients who also have ME/CFS.<ref name="FuLevine2018" /><ref name="JoynerMasuki2008" /><ref name="Joyner2012" /><ref name="pmid30372565" /><ref name="GeorgeBivensHowden2016">Template:Cite journal</ref> Aerobic exercise performed for 20 minutes a day, three times a week, is sometimes recommended for patients who can tolerate it.<ref name="Grubb_2006" /> Exercise may have the immediate effect of worsening tachycardia, especially after a meal or on a hot day.<ref name="Mathias_2012" /> In these cases, it may be easier to exercise in a semi-reclined position, such as riding a recumbent bicycle, rowing, or swimming.<ref name="Mathias_2012" /> Although exercise may be difficult initially, it may become progressively easier as physical conditioning improves.<ref name="FuLevine2018" /><ref name="JoynerMasuki2008" /><ref name="Joyner2012" />

When changing to an upright posture, finishing a meal, or concluding exercise, a sustained hand grip can briefly raise the blood pressure, possibly reducing symptoms.<ref name="Mathias_2012" /> Compression garments can also be of benefit by constricting the blood vessels with external body pressure.<ref name="Mathias_2012" />

Aggravating factors include exertion (81%), continued standing (80%), heat (79%), and after meals (42%).<ref name="pmid10560597">Template:Cite journal</ref>

Medication

If non-pharmacological methods are ineffective, medication may be necessary.<ref name="Mathias_2012" /> Medications used may include beta blockers, pyridostigmine, midodrine,<ref name="pmid24253613">Template:Cite journal</ref> or fludrocortisone, among others.<ref name="pmid11710800">Template:Cite journal</ref><ref name="pmid23122672"/> As of 2013, no medication has been approved by the U.S. Food and Drug Administration to treat POTS, but a variety are used off-label.<ref name="pmid23753844" /> Their efficacy has not yet been examined in long-term randomized controlled trials.<ref name="pmid23753844" />

Fludrocortisone, a mineralocorticoid, may be used to enhance sodium retention and blood volume, which may be beneficial not only by augmenting sympathetically mediated vasoconstriction, but also because a large subset of POTS patients appear to have low absolute blood volume.<ref name="hrsonline.org">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> However, fludrocortisone may cause hypokalemia (low potassium levels).<ref name="pmid33232001">Template:Cite book</ref>

While people with POTS typically have normal or even elevated arterial blood pressure, the neuropathic form of POTS is presumed to constitute a selective sympathetic venous denervation.<ref name="hrsonline.org" /> In these patients the selective α1-adrenergic receptor agonist midodrine may increase venous return, enhance stroke volume, and improve symptoms.<ref name="hrsonline.org" /> Midodrine should only be taken during the daylight hours as it may promote supine hypertension.<ref name="hrsonline.org" />

Sinus node blocker ivabradine can successfully restrain heart rate in POTS without affecting blood pressure, as demonstrated in approximately 60% of people with POTS treated in an open-label trial of ivabradine experienced symptom improvement.<ref name="pmid21062792">Template:Cite journal</ref><ref name="pmid32489723">Template:Cite journal</ref><ref name="hrsonline.org" />

Pyridostigmine, an acetylcholinesterase inhibitor and parasympathomimetic, has been reported to restrain heart rate and improve chronic symptoms in approximately half of POTS patients reviewed. However, it may cause GI side effects that limit its use in around 20% of its patient population.<ref name="pmid21410722">Template:Cite journal</ref><ref name="pmid23753844" />

The selective α1-adrenergic receptor agonist phenylephrine has been used successfully to enhance venous return and stroke volume in some people with POTS.<ref name="Government-of-South-Australia-2017">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> However, this medication may be hampered by poor oral bioavailability.<ref name="Meta-2017">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Indirectly acting sympathomimetics, like the norepinephrine releasing agents ephedrine and pseudoephedrine and the norepinephrine–dopamine reuptake inhibitors methylphenidate and bupropion, have also been used in the treatment of POTS.<ref name="pmid38465412" /><ref name="VyasNesheiwatRuzieh2020">Template:Cite journal</ref><ref name="Fedorowski-2018" /><ref name="pmid20460983" /> The norepinephrine prodrug droxidopa has been used as well.<ref name="Fedorowski-2018" /><ref name="pmid27563801" />

Pharmacologic treatments for postural tachycardia syndrome
POTS subtypes Therapeutic action Goal Drug(s)
Neuropathic POTS α1-Adrenergic receptor agonist Constrict the peripheral blood vessels, aiding venous return. Midodrine<ref name="Chen_2011" /><ref name="Lai_2009">Template:Cite journal</ref><ref name="Yang-2014">Template:Cite journal</ref><ref name="pmid19099860">Template:Cite journal</ref>
Splanchnic–mesenteric vasoconstriction Splanchnic vasoconstriction Octreotide<ref name="Khan_2015">Template:Cite journal</ref><ref name="pmid17036177">Template:Cite journal</ref>
Hypovolemic POTS Synthetic mineralocorticoid Forces the body to retain salt. Increase blood volume Fludrocortisone (Florinef)<ref name="Freitas_2000">Template:Cite journal</ref><ref name="Gall-2021">Template:Cite bookTemplate:Page needed</ref>
Vasopressin receptor agonist Helps retain water, increases blood volume Desmopressin (DDAVP) <ref name="pmid22561596">Template:Cite journal</ref>
Hyperadrenergic POTS Beta-blockers (non-selective) Decrease sympathetic tone and heart rate. Propranolol (Inderal)<ref name="pmid21690484">Template:Cite journal</ref><ref name="pmid23616163">Template:Cite journal</ref><ref name="pmid19687359">Template:Cite journal</ref>
Beta-blockers (selective) Metoprolol (Toprol),<ref name="Lai_2009" /><ref name="pmid18339272">Template:Cite journal</ref> Bisoprolol<ref name="pmid29500811">Template:Cite journal</ref><ref name="Freitas_2000" />
Selective sinus node blockade Directly reducing tachycardia. Ivabradine<ref name="pmid21062792" /><ref name="pmid32489723" /><ref name="pmid26241226">Template:Cite journal</ref><ref>Template:Cite journal</ref><ref name="pmid33602468">Template:Cite journal</ref>
α2-Adrenergic receptor agonist Decreases blood pressure and sympathetic nerve traffic. Clonidine,<ref name="pmid23753844" /> Methyldopa<ref name="pmid23753844" />
Anticholinesterase inhibitors Splanchnic vasoconstriction. Increase blood pressure. Pyridostigmine<ref name="Kanjwal_2011" /><ref name="pmid15911704">Template:Cite journal</ref><ref name="Clinical-trial number-NCT00409435 for-00409">Template:ClinicalTrialsGov</ref>
Other (refractory POTS) Psychostimulant Improve cognitive symptoms (brain fog) Modafinil<ref name="pmid25222185">Template:Cite journal</ref><ref name="Clinical trial number NCT01988883">Template:ClinicalTrialsGov</ref>
Central nervous system stimulant Tighten blood vessels. Increases alertness and improves brain fog. Methylphenidate (Ritalin, Concerta)<ref name="pmid20460983">Template:Cite journal</ref>
Direct and indirect α1-adrenoreceptor agonist. Increased blood flow Ephedrine and Pseudoephedrine<ref name="Fedorowski-2018">Template:Cite book</ref>
Norepinephrine precursor Improve blood vessel contraction Droxidopa (Northera)<ref name="Fedorowski-2018" /><ref name="pmid27563801">Template:Cite journal</ref>
α2-Adrenergic receptor antagonist Increase blood pressure Yohimbine<ref name="Goldstein-2002">Template:Cite book</ref>

Prognosis

POTS has a favorable prognosis when managed appropriately.<ref name="Mathias_2012" /> Symptoms improve within five years of diagnosis for many patients, and 60% return to their original level of functioning.<ref name="Mathias_2012" /> Approximately 90% of people with POTS respond to a combination of pharmacological and physical treatments.<ref name="pmid18506020"/> Those who develop POTS in their early to mid teens will likely respond well to a combination of physical methods as well as pharmacotherapy.<ref name="agarwal2007">Template:Cite journal</ref> Outcomes are more guarded for adults newly diagnosed with POTS.<ref name="pmid20117742">Template:Cite journal</ref> Some people do not recover, and a few even worsen with time.<ref name="pmid18506020"/> The hyperadrenergic type of POTS typically requires continuous therapy.<ref name="pmid18506020"/> If POTS is caused by another condition, outcomes depend on the prognosis of the underlying disorder.<ref name="pmid18506020"/>

Epidemiology

The prevalence of POTS is unknown.<ref name="Mathias_2012">Template:Cite journal</ref> One study estimated a minimal rate of 170 POTS cases per 100,000 individuals, but the true prevalence is likely higher due to underdiagnosis.<ref name="Mathias_2012" /> Another study estimated that there are at least 500,000 cases in the United States.<ref name="pmid27578452"/> POTS is more common in women than men, with a female-to-male ratio of 4:1.<ref name="pmid19207771">Template:Cite journal</ref><ref name="pmid30079848">Template:Cite journal</ref> Most people with POTS are aged between 20 and 40, with an average onset of 21.<ref name="pmid30861229" /><ref name="pmid19207771" /> Diagnoses of POTS beyond age 40 are rare, perhaps because symptoms improve with age.<ref name="Mathias_2012" />

Research directions

A key area for further exploration of POTS management is the autonomic nervous system and its response to the orthostatic challenge. The autonomic nervous system plays a crucial role in maintaining cardiovascular homeostasis during changes in posture. A deeper understanding of its function and the alterations that occur in POTS could provide valuable insights into potential therapeutic targets and the mechanisms of POTS treatment.<ref name="pmid38465412"/>

History

In 1871, physician Jacob Mendes Da Costa described a condition that resembled the modern concept of POTS. He named it irritable heart syndrome.<ref name="Mathias_2012" /> Cardiologist Thomas Lewis expanded on the description, coining the term soldier's heart because it was often found among military personnel.<ref name="Mathias_2012" /> The condition came to be known as Da Costa's syndrome,<ref name="Mathias_2012" /> which is now recognized as several distinct disorders, including POTS.Template:Citation needed

Postural tachycardia syndrome was coined in 1982 in a description of a patient who had postural tachycardia, but not orthostatic hypotension.<ref name="Mathias_2012" /> Ronald Schondorf and Phillip A. Low of the Mayo Clinic first used the name postural orthostatic tachycardia syndrome, POTS, in 1993.<ref name="Mathias_2012" /><ref name="pmid8423877">Template:Cite journal</ref>

Notable cases

British politician Nicola Blackwood revealed in March 2015 that she had been diagnosed with Ehlers–Danlos syndrome in 2013 and that she had later been diagnosed with POTS.<ref name="Rodgers-2015">Template:Cite news</ref> She was appointed Parliamentary Under-Secretary of State for Life Science by Prime Minister Theresa May in 2019 and given a life peerage that enabled her to take a seat in Parliament. As a junior minister, it is her responsibility to answer questions in parliament on the subjects of Health and departmental business. When answering these questions, it is customary for ministers to sit when listening to the question and then to rise to give an answer from the despatch box, thus standing up and sitting down numerous times in quick succession throughout a series of questions. On 17 June 2019, she fainted during one of these questioning sessions after standing up from a sitting position four times in the space of twelve minutes,<ref name="hansard.parliament.uk-2019">{{#invoke:citation/CS1|citation |CitationClass=web }} Baroness Blackwood of North Oxford makes four speeches (thus standing up four times) between 5:52 PM and 6:04 PM.</ref> and it was suggested that her POTS was a factor in her fainting. Asked about the incident, she stated: "I was frustrated and embarrassed my body gave up on me at work ... But I am grateful it gives me a chance to shine a light on a condition many others are also living with."<ref name="House of Lords collapse-2019">Template:Cite news</ref>

In 2024, Taiwanese tennis player Latisha Chan revealed that she was diagnosed with POTS back in 2014 and has been receiving treatments before Summer Olympics as well. Her condition was considered career-threatening, but has had her career extended by over a decade due to external counterpulsation.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

In her 2024 memoir Just Add Water, Olympic gold medalist swimmer Katie Ledecky shared that she has a mild form of POTS.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Latvian basketball player Kristaps Porziņģis was sidelined for much of the 2024–25 NBA season with POTS.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

References

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Further reading

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de:Orthostatische Dysregulation#Posturales Tachykardiesyndrom (POTS)

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