Postural Orthostatic Tachycardia Syndrome (POTS) is a chronic condition affecting the autonomic nervous system, characterized primarily by an abnormally large increase in heart rate when a person moves from lying down or sitting to standing up. Specifically, adults with POTS experience an increase of at least 30 beats per minute within 10 minutes of standing, while adolescents have a threshold of 40 beats per minute
. Key features and symptoms of POTS include:
- Rapid heartbeat (tachycardia) upon standing, often exceeding 120 beats per minute
- Symptoms of orthostatic intolerance such as dizziness, lightheadedness, fainting (syncope), palpitations, weakness, blurred vision, brain fog, fatigue, headaches, nausea, chest pain, and shortness of breath
- Symptoms typically worsen with prolonged standing, heat exposure, physical exertion, large meals, or during menstruation and pregnancy
- Some patients experience blood pooling in the legs, causing a reddish-purple discoloration when standing
- Many patients report chronic fatigue and sleep disturbances, and some have difficulty with exercise and daily activities due to symptom severity
Causes and associations: POTS is a form of dysautonomia involving abnormal autonomic nervous system regulation. It may be linked to autoimmune factors, neuropathy, hypovolemia (low blood volume), and hyperadrenergic states. It is also associated with conditions like Ehlers-Danlos syndrome, mast cell activation syndrome, and chronic fatigue syndrome
. Diagnosis: Diagnosis involves measuring heart rate changes upon standing or during a tilt table test, ruling out other causes like orthostatic hypotension or dehydration
. Management: There is no cure for POTS, but symptoms can be managed through lifestyle changes such as increasing fluid and salt intake, wearing compression stockings, avoiding triggers, and tailored exercise programs. Medications like beta blockers, ivabradine, and fludrocortisone may be used off-label to help control symptoms. Physical therapy is often recommended
. Prognosis: While POTS is not life-threatening and does not reduce life expectancy, it can significantly impair quality of life. Approximately 90% of patients improve with treatment, though about 25% may have persistent symptoms that limit their ability to work or perform daily activities
. In summary, POTS is a complex autonomic disorder causing excessive heart rate increase and a range of symptoms upon standing, managed through a combination of lifestyle adjustments, supportive therapies, and medications. It affects millions worldwide and requires individualized care to improve function and quality of life.
