Postural orthostatic tachycardia syndrome (POTS) is a condition in which a change from lying to standing causes an abnormally large increase in the heart rate. This occurs with symptoms such as lightheadedness, trouble thinking, blurry vision or weakness.
POTS is often associated with other conditions such as irritable bowel syndrome, insomnia, chronic headaches, Ehlers-Danlos syndrome, chronic fatigue syndrome and fibromyalgia. The cause of POTS is not understood. Often it begins with a viral infection, surgery or pregnancy.
- Increase in heart rate of more than 30 bpm within 10 minutes of upright posture
- Chronic symptoms lasting longer than 6 months
- Absence of disorders such as prolonged bed rest, use of medications that impair autonomic regulation or functional states that predispose to orthostatic tachycardia
- Increase salt and water intake
- Graded physical therapy
- Medications can be prescribed such as beta-blockers, pyridostigmine, midocrine or fludrocortisone. But their efficacy has not been examined in randomized controlled trials.
When a patient also has chronic fatigue syndrome, recovery might be difficult. One of the criteria of chronic fatigue syndrome is exercise intolerance and these patients might not tolerate graded physical therapy.
Most patients improve within 5 years and 60% return to their original level of functioning.