1. Scientific Background
Postural Orthostatic Tachycardia Syndrome (POTS)
Shannon Stewart
Calvin College, Grand Rapids, Michigan
Disease Summary
Scientific Background
Treatment Strategies
Postural orthostatic tachycardia syndrome (POTS) is a condition characterized by too little blood returning to the heart during positional changes. This is termed orthostatic intolerance and can often be accompanied with lightheadedness, exhaustion, fainting and increased heart rate.
Although POTS can affect both men and women of all ages, the most prominent demographic are white females between the ages of 15 and 50.
The cause of POTS is unknown, although there have been studies that provide evidence that many POTS patients begin experiencing symptoms soon after a traumatic experience. These experiences could include surgery, concussion, viral infection or a any other serious episode.
Simple lifestyle changes such as adding extra salt to the diet, drinking more fluids, exercising and avoiding factors that make the condition worse may lessen the severity of symptoms
If the patient is experiencing very low blood pressure, pharmacuticals can be used such as fludrocortisone (a steroid that helps with volume repletion), mitodrine (help increase constriction of splanchnic vessels and dilation of renal vasculature), and beta blockers
Additional treatments could include wearing compression stockings.
Genetics
Although most cases of POTS occur in people with no family history of this specific condition, some patients report a family history of orthostatic intolerance.
Some studies suggest that normal variation in certain genes, specifically NOS3 and ADRB2, may be associated with an increased risk of developing the condition
One family with a number of members diagnosed with POTS had a mutation in the norepinephrine transporter gene, SLC6A2.
References
Biochemistry: Concepts and Connections, Appling
Gene Reviews: Nuclear Gene-Encoded Leigh Syndrome Overview
NIH Genetics Home Reference
NIH Genetics and Rare Diseases Information Center (GARD)
Resources
Recent Advances
Clinical Trials
ClinicalTrials.gov lists trials that are related to Postural orthostatic tachycardia syndrome. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies. 
Patient Registry
The Autonomic Rare Diseases Clinical Research Consortium is a team of doctors, nurses, and researchers who strive to improve the lives of people with rare autonomic disorders through research. This organization has a registry for patients who wish to be contacted about clinical research opportunities. For more information on the registry see:
Signs and Symptoms
Blurred vision
Lightheadedness, dizziness or fainting
Heart palpitations
Headache
Poor concentration
Tiredness
Gastrointestinal symptoms (for example, nausea, cramps, bloating, constipation, diarrhea)
Shortness of breath
Head, neck or chest discomfort
Weakness
Sleep disorders
Difficulty exercising
Anxiety
Coldness or pain in the extremities