What is Postural Orthostatic Tachycardia Syndrome (POTS)?

From the Guidelines

Postural orthostatic tachycardia syndrome (POTS) is a condition that should be managed with a combination of non-pharmacological approaches and medications to reduce symptoms and improve quality of life, with the goal of increasing blood volume, improving vasoconstriction, and managing heart rate.

Definition and Diagnosis

POTS is characterized by an abnormal increase in heart rate when moving from a lying to standing position, accompanied by symptoms like dizziness, fatigue, and brain fog 1. The diagnosis of POTS is based on the presence of frequent symptoms that occur with standing, an increase in heart rate of ≥30 bpm during a positional change from supine to standing, and the absence of orthostatic hypotension (>20 mm Hg reduction in systolic BP) 1.

Management

Management of POTS typically begins with non-pharmacological approaches, including:

• Increased fluid intake (2-3 liters daily) and salt consumption (8-10g daily) to increase blood volume
• Compression garments for the lower body to improve vasoconstriction
• A gradual exercise program focusing on recumbent exercises initially to improve cardiovascular function Medications may also be used to manage POTS, including:
• Beta-blockers like propranolol (10-20mg as needed or 10-40mg twice daily) to reduce heart rate
• Fludrocortisone (0.1-0.2mg daily) to increase blood volume
• Midodrine (2.5-10mg three times daily) for vasoconstriction
• Ivabradine (2.5-7.5mg twice daily) to reduce heart rate without affecting blood pressure 1.

Pathophysiology

POTS occurs when the autonomic nervous system fails to properly regulate blood vessel constriction upon standing, causing blood pooling in the lower extremities and requiring increased heart rate to maintain blood flow to the brain 1. The pathophysiology of POTS is complex and multifactorial, involving deconditioning, immune-mediated processes, excessive venous pooling, and a hyperadrenergic state 1.

Treatment Goals

The goal of treatment for POTS is to reduce symptoms and improve quality of life by increasing blood volume, improving vasoconstriction, and managing heart rate 1. Treatment should be individualized and based on the specific needs and symptoms of each patient.

From the Research

Definition and Characteristics of Postural Orthostatic Tachycardia Syndrome (POTS)

• POTS is a form of cardiovascular autonomic disorders characterized by orthostatic intolerance and a symptomatic increase in heart rate upon standing, which can significantly impair patients' quality of life 2.
• Patients often experience a constellation of other typical symptoms including fatigue, exercise intolerance, and gastrointestinal distress 3.
• A typical patient with POTS is a female of child-bearing age, who often first displays symptoms in adolescence 3.

Pathophysiology and Phenotypes of POTS

• The pathophysiology of POTS is complex and multifactorial, involving various mechanisms such as hyperadrenergic, neuropathic, and hypovolemic phenotypes 2.
• Each phenotype requires tailored management strategies, with hyperadrenergic POTS involving excessive norepinephrine production or impaired reuptake, neuropathic POTS resulting from impaired vasoconstriction, and hypovolemic POTS often triggered by dehydration and physical deconditioning 2.

Diagnosis and Treatment of POTS

• The evaluation of a patient with suspected POTS should seek to establish the diagnosis, identify co-morbid conditions, and exclude conditions that could cause or mimic the syndrome 3.
• Management typically begins with patient education and non-pharmacologic treatment options, including increased fluid and salt intake, compression garment use, physical reconditioning, and postural training 2, 3.
• Various medications are often used to address specific symptoms, such as beta-blockers for hyperadrenergic POTS, pyridostigmine and midodrine for neuropathic POTS, and volume expansion and exercise for hypovolemic POTS 2, 4, 5.
• However, there are currently no FDA-approved medications for the treatment of POTS, and evidence for many of the medications used to treat POTS is limited 2, 3, 4.

POTS After COVID-19

• POTS has been associated with Coronavirus Disease 2019 (COVID-19) as part of the postacute sequelae of COVID-19 (PASC) or long-COVID 6.
• Symptoms of POTS after COVID-19 tend to improve over time, but most patients remain symptomatic for several months, and nonpharmacologic treatments are often ineffective 6.
• Pharmacological interventions, such as beta-adrenergic blockers, mineral corticosteroids, midodrine, and ivabradine, may be effective in improving symptoms 6.