Understanding Postural Orthostatic Tachycardia Syndrome
Standing Up
When the body moves from a lying down to an upright position several changes occur in reaction to the pull of gravity. These adjustments are made to ensure that homeostasis continues. Blood pressure shifts, vessels contract, and the heart rate increases all to make sure the right amount of blood reaches the heart so the body can quickly and easily stand up. With postural orthostatic tachycardia syndrome, or POTS, the body does not self-regulate properly. While for most people the autonomic nervous system acts to regulate blood flow throughout the body, people who have POTS experience dysregulation of the autonomous nervous system — actions and reactions do not occur as they are supposed to, leading to a host of problematic symptoms.
Characteristics
POTS is one of several conditions involving orthostatic intolerance, the primary symptom of the disorder. Orthostatic intolerance is when an excessively lessened quantity of blood returns to the heart when the body stands up. This results in lightheadedness and fainting. With POTS, the heart rate rapidly increases, exceeding 120 beats per minute for about ten minutes. About half of patients who suffer from this syndrome also experience generalized weakness.
An exaggerated heart rate and serious lightheadedness upon rising is the main characteristic of this disorder, although people can suffer from other problems related to autonomic nervous system dysregulation. Other potential symptoms include digestive troubles such as nausea or cramping due to improper blood flow, palpitations, shortness of breath, excessive or loss of sweating, fatigue, sleep trouble, headaches, dizziness, chills, and anxiety.
Causes
What causes this disorder? Who is at risk? The cause behind POTS is believed to be problems with the sympathetic nervous system (the part of the autonomic nervous system that is involved with how the body reacts to stress, which involves heartbeat changes). Why exactly the nervous system starts to function abnormally is unclear although in many cases the symptoms of postural orthostatic tachycardia appear after a major ordeal that involves serious stress to the body such as surgery, giving birth, overcoming a virus, or chemotherapy. Teenagers also may experience POTS symptoms during the rapid growth period of the teenage years.
It is unclear how many people suffer from this syndrome although in general women are much more likely then men to have POTS. Anyone from a teenager to an adult can have this condition and the number of and severity of symptoms varies greatly. Also, in many cases symptoms do lessen or go away with time and treatment.
Treating POTS
Is POTS treatable? What treatment options are available? There is not one single treatment for orthostatic tachycardia, but rather a series of options catered to the individual. Dietary changes including increasing salt intake, eating small meals, and avoiding alcohol can help. Drinking two glasses of water before sitting up is a useful tactic. Sleeping with a tilted bed, so the head is upright can help prevent fainting. Different medications are available, such as fludrocortisone and midodrine to increase blood volume and narrow blood vessels. Exercise is another form of therapy for orthostatic intolerance.
If experiencing symptoms of POTS be sure to see your doctor. While orthostatic intolerance can be difficult to deal with and even interfere with everyday life, there are potential solutions. Talk to your doctor, learn about the disorder, and discover how to live a high quality of life despite POTS.
References
National Institute of Neurological Disorders and Stroke https://www.ninds.nih.gov/disorders/postural\_tachycardia\_syndrome/postural\_tachycardia\_syndrome.htm
Dysautonomia Information Network https://www.dinet.org/pots\_an\_overview.htm
Mayo Clinic https://podcasts.mayoclinic.org/2008/04/23/postural-orthostatic-tachycardia-syndrome-pots/
photo by Carl Nenzen Loven