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Postural orthostatic tachycardia syndrome (POTS) is the final common pathway of a heterogeneous group of underlying disorders that display similar clinical characteristics

Earth bound astronaut
Autonomic system shot
One can barely stand
Slow tilt, near faint, cold sweaty
Racing against gravity Link to author

About

• POTS is a heterogeneous group of disorders resulting in a common clinical scenario.

Aetiology: unclear cause

• Neuroendocrine dysfunction
• Small fiber neuropathy
• MAST cell activation
• Seen to have high plasma norepinephrine levels

Definition: Diagnostic criteria

• Heart rate increases +30 bpm from supine to standing (10 min)
• Symptoms worsen with standing and improved with recumbence
• Symptoms last > 6 mo
• Absence of other overt cause of orthostatic symptoms or tachycardia (eg, active bleeding, acute dehydration, medications)

Clinical

• Female > Male 5:1
• Onset after viral illness, COVID, pregnancy, immunization, sepsis, surgery, trauma.
• Orthostatic intolerance, palpitations, fatigue
• Frequent episodes of light headedness and near syncope.
• Exercise intolerance and dyspnoea on exertion
• Exacerbation of symptoms around menstruation
• Fatigue, unrefreshing sleep, and daytime sleepiness.
• Irritable bowel syndrome, hypermobile joints, abnormal sudomotor regulation.
• 50% have a dependent acrocyanosis seen below in the person on the right. There is a dark red-blue discoloration of their legs (feet to above knees), which are cold to the touch.

Dependent acrocyanosis

Investigations

• FBC, U&E, LFTs, CRP - normal
• ECG - resting normal
• Echo - normal
• 24 hr tape - epsodes of tachycardia
• Positive tilt table

Management

• Stopping drugs that could contribute: antidepressants, Antihypertensive, Ethanol, Opiates, Sildenafil citrate. Volume replacement and Vasoconstrictors. Management is largely trial and error to make quality of life optimal.
• Reconditioning: Aerobic exercise 20 min 3 times / week. If too vigorous may worsen symptoms. Some unable to exercise due to fatigue etc.
• Intravenous saline (immediate effect) 1 L over 1–2 h IV; short-term emergency treatment
• Panty hose–style compression stockings: 30–40 mm Hg counterpressure
• Hydration: 2 liters PO/day could cause oedema
• Salt added 2-4 grams/day can cause oedema
• Fludrocortisone 0.1-0.2 mg PO daily. May cause Hypokalemia, hypomagnesemia, edema
• Desmopressin (DDAVP):0.2 mg orally 1 time for occasional use. Could cause hyponatremia with regular use
• Midodrine: 5-10 mg PO TID. May cause Nausea, scalp pruritus, supine hypertension
• Metoprolol: may be beneficial in adolescent type POTS patients
• Erythropoietin: Severely affected and refractory patients. EPO increases red cell mass, central blood volume and augments response of blood vessels to the angiotensin-II and thus causes vasoconstriction.
• There are many other medications trialed. See references below

References

• Postural Orthostatic Tachycardia Syndrome (POTS): Evaluation and Management
• POTS Review from the AHA