POSTURAL ORTHOSTATIC TACHYCARDIA SYNDROME (POTS)
WHAT IS POTS?
Postural orthostatic tachycardia syndrome, also known as POTS, is a chronic condition epitomized by an insufficient supply of blood returning to the heart when moving from a lying down to a standing up position. Another name for this chronic, yet common disease is orthostatic intolerance. Orthostatic intolerance causes fainting or lightheadedness, which can be relieved by lying down again. For patients with POTS, a rapid, sudden surge in heart rate is also paired with these symptoms. Both men and women, regardless of their age, can contract this disorder. However, most cases of POTS are diagnosed in women between the ages of 15 and 50. Although episodes often start after a major surgery, trauma, or viral illness, the true cause of POTS is still unknown. In women, episodes may also begin after pregnancy. Just before menstruation, the number of episodes may increase or the symptoms may worsen. The goal of treatment is to increase blood flow and improve circulatory problems that may be causing POTS.
WHAT ARE THE SYMPTOMS OF POTS?
The primary symptoms of postural orthostatic tachycardia syndrome, a.k.a. POTS, are orthostatic intolerance and rapid, sudden surges in heart rate. Often, people with POTS also have hypovolemia, a decreased volume of circulating blood, and increased levels of plasma norepinephrine while standing, which mirrors increased sympathetic nervous system activation. Around half of the afflicted individuals also have a small fiber neuropathy that impacts their sudomotor nerves – nerves that activate the sweat glands. A few patients experience a reddish-purple color in their legs upon standing. It is believed that blood pooling or poor circulation are to blame for this. However, when these individuals return to a reclined position, the change in color subsides.
Additional symptoms that have been reported in patients with POTS include:
Chest, Head, Or Neck Discomfort
Coldness / Pain In The Extremities
Gastrointestinal Symptoms (Bloating, Constipation, Cramps, Diarrhea, Nausea, etc.)
Shortness Of Breath
Although the true cause of POTS is still being researched, several underlying conditions have been connected to POTS or to symptoms commonly seen in POTS.
WHAT ARE THE CAUSES OF POTS?
The true cause of postural orthostatic tachycardia syndrome, better known as POTS, is still unknown. However, episodes often start after a major surgery, pregnancy, trauma, or viral illness, and could even increase just before a menstrual period.
Many researchers speculate that this condition has more than just one cause. The abnormalities listed below could be linked to POTS and may play a role in its development:
An abnormal decrease in the volume of circulating blood in the body (caused, for example, by blood pooling in the abdomen and legs).
An abnormal regulation of blood pressure.
An increased fight-or-flight response.
An insufficient supply of blood returning to the heart when moving from a lying down to a standing up position.
Changes in blood vessel and heart function.
Impaired function of nerves in certain muscles, especially those in the feet and legs.
Although most cases of POTS are diagnosed in patients with no family history of the condition, a few patients have mentioned a family history of orthostatic intolerance. This means that genetic factors might play a role in the development of POTS, at least in some cases. Additionally, some studies suggest that normal variations, or polymorphisms, in certain genes, like ADRB2 or NOS3, could be associated with an increased risk of developing the disorder. A mutation in the norepinephrine transporter gene, SLC6A2, has also been found in one family with POTS.
WHAT IS THE DIAGNOSIS FOR POTS?
A diagnosis of postural orthostatic tachycardia syndrome, a.k.a. POTS, is often suspected based on characteristic signs and distinctive symptoms. To confirm the diagnosis, additional examination can then be ordered. Most physicians will conduct physical testing that includes measuring of one’s blood pressure and heart rate while lying, sitting, and standing. A tilt table test might also be recommended. This test involves checking an individual’s blood pressure and heart rate while this person is safely moved from a lying down to a standing up position.
WHAT IS THE TREATMENT FOR POTS?
Because research suggests that postural orthostatic tachycardia syndrome, otherwise known as POTS, has multiple different causes, no single treatment works for every affected individual. Management of POTS strives to correct issues with the blood vessels and heart which may be causing the condition and improve low blood pressure. For those with POTS, subtle lifestyle changes, such as adding additional salt to the diet, avoiding factors that worsen the condition, drinking extra fluids, and exercising, could lessen symptoms. Certain medications might also be helpful in treating POTS. Some researchers recommend fludrocortisone (0.05 to 0.2 mg daily) and volume repletion as the first line of therapy. A few patients have benefitted after taking beta blocking agents or midodrine. Further medical options for treatment are still under proper examination; additional confirmation for the benefits they claim to provide are necessary for professional recommendation.
WHAT IS THE PROGNOSIS FOR POTS?
For individuals with postural orthostatic tachycardia syndrome, a.k.a. POTS, the long-term outlook / prognosis is generally good. However, an overall poor outlook / prognosis is still possible, even if rather unlikely. Many patients can continue with their regular daily activities, experiencing only mild symptoms. Unfortunately, not everyone that contracts this disease is so lucky. Some individuals are affected severely and have their abilities exceptionally limited. Most people with POTS report considerable improvements in their symptoms within 12 months. Rarely, an individual won’t see improvement after their treatment, and could even grow worse over time.
With changes towards a healthier lifestyle (for example, diet and exercise) and medical treatments, many affected people see an improvement in symptoms and quality of life. Occasionally, patients with POTS even grow to be symptom-free over time.