POTS is a disorder affecting the central nervous syndrome that can cause debilitating symptoms in people who were previously healthy.
What is POTS?
POTS may cause symptoms such as shortness of breath, dizziness, and chest pains when standing up.
POTS stands for postural orthostatic tachycardia syndrome. Breaking POTS down based on its name can provide insight into the condition:
- Postural means the condition is related to the posture of the body.
- Orthostatic also suggests the body's position is involved and refers to dizziness and a sudden drop in blood pressure.
- Tachycardia means a rapid heartbeat, generally over 100 beats per minute.
- Syndrome means it is not a disease but rather a group of symptoms that are often seen together.
POTS is characterized by an increased heart rate, drop in blood pressure, and dizziness upon standing. This happens because the heart does not get enough blood when a person stands up, so the heartbeat increases to try to improve the blood circulation.
POTS is a type of dysautonomia, which are disorders of the part of the nervous system that regulates blood pressure, heart rate, and breathing patterns.
While POTS syndrome is characterized by the rapid rise in heart rate upon standing, a person with POTS may experience a wide variety of symptoms, including:
- increased heart rate in the first 10 minutes of standing
- drop in blood pressure
- pain in hands and feet
- heart palpitations
- tremors or shaking
- exercise intolerance
- shortness of breath
- chest pain
- decreased ability to concentrate
- pain or coldness in extremities
The combination of POTS symptoms varies from person to person. A person with POTS may have symptoms that range from mild to debilitating.
Causes and risk factors
If pregnancy causes POTS, the symptoms may subside after the pregnancy.
Scientists are not sure what causes POTS. However, some researchers believe that POTS may be more likely to occur right after the following events:
- a pregnancy
- severe illness or injury
- major surgery
- anything that causes changes in the function of the heart or blood vessels
- damaged nerves or impaired nerve function in the feet or legs
- prolonged periods of increased fight-or-flight responses
While researchers are still looking for the exact cause or causes of this condition, they have identified several underlying conditions and diseases that frequently occur in people with POTS.
These include the following:
- autoimmune diseases
- diabetes or prediabetes
- deconditioning or prolonged bed rest
- Epstein Barr virus
- Lyme disease
- Ehlers Danlos syndrome
- vitamin and mineral deficiencies, including anemia
While many people who develop POTS have no family history of the condition, some people who have POTS report a family history of conditions that result in an increased heart rate while standing.
Because some people diagnosed with POTS have a family history of similar conditions, there may be a genetic component involved.
The majority of those diagnosed with POTS are women between age 15 and 50. However, POTS can affect people of any age or sex.
A person that believes they may have POTS should keep a detailed record of their symptoms. A healthcare professional can review these symptoms and will then likely assess the person's overall health.
A family doctor may refer a person who has symptoms of POTS to a cardiologist or neurologist for further testing to see if the person meets the diagnostic criteria for POTS.
For a doctor to diagnose a person with POTS, the person must have symptoms of orthostatic intolerance and meet the following criteria:
- People over 19 years old must have an increase in heart rate of at least 30 beats per minute (bpm) within 5 minutes of standing up.
- People between 12 and 19 must have an increased heart rate of 40 bpm or more within 5 minutes of standing up.
- Symptoms must have been occurring for at least 6 months.
Diagnosing POTS may include the following tests to confirm the increase in heart rate while ruling out other problems:
- a tilt table test
- electrocardiogram (ECG)
- an active stand test
During a tilt table test, a person will lay flat on a table in a quiet room for a set amount of time before the head of the table is raised to 60–75° angle.
The person's heart rate and blood pressure will be monitored for the duration of the test, and a doctor may ask the person to describe how they are feeling periodically. A person with POTS will have an increase in heart rate of at least 30 bpm after the head of the table is raised.
During an ECG, small electrodes are attached to the chest to measure the heart's rhythm. This test is done to exclude any other heart problems that may cause symptoms similar to POTS.
An active stand test is similar to a tilt table test. A person's heart rate and blood pressure will be monitored first while they are lying down and during and after they stand up.
Diagnosing POTS can be difficult. Because it is a poorly understood condition with many symptoms, it can take years for someone with POTS to be properly diagnosed.
Exercising from a seating position, such as using a recumbent bike, may help treat POTS.
Unfortunately, there is no standard treatment for POTS. Finding the right treatment may take a bit of trial and error. Doctors will usually focus on treating any underlying problems with the heart or blood vessels, and on raising low blood pressure.
Doctors may recommend a combination of lifestyle changes and medications to treat POTS.
Common lifestyle modifications for POTS include the following:
- wearing compression stockings
- increasing fluid consumption
- increasing salt intake
- exercising as tolerated in a seated position, such as on a recumbent bike
- raising the head of the bed
A doctor may also prescribe medication to treat POTS. Medication for POTS typically addresses the lack of blood volume and regulates the nervous system.
It can include a combination of the following:
- beta blockers
The long-term outlook for people with POTS is inconclusive, as there have been few studies carried out on the condition. However, there is evidence that some people with POTS see an improvement in their symptoms with lifestyle modifications and medication.
The majority of people with POTS will experience a lessening of their symptoms with treatment or over time. Some may even have a complete resolution of POTS symptoms.
Anyone experiencing the symptoms of POTS should see their doctor for a diagnosis and to rule out any underlying heart conditions.