What Is Postural Orthostatic Tachycardia Syndrome (POTS)?
POTS stands for:
- Postural — means posture or the position of your body.
- Orthostatic — a drop in blood pressure when you stand up after sitting or lying down.
- Tachycardia — a rapid heart rate.
- Syndrome — a group of symptoms.
In a healthy person, the autonomic nervous system (ANS) controls involuntary actions in your body like:
- Blood pressure.
- Heart rate.
- The speed of blood flow.
When changing position, such as sitting or standing, the heart rate must increase and blood vessels must tighten. This lets blood pump against the forces of gravity and keeps your circulation moving at a normal pace.
POTS is an abnormal response to your ANS, causing most of your blood to stay in your lower body when you stand.
With POTS, this malfunction in the ANS can cause:
- A fast heart rate.
- A drop in blood pressure.
- Lightheadedness, dizziness, or fainting.
These symptoms occur because your heart must beat even faster to get blood to the brain and rest of the body.
POTS affects between 1 to 3 million Americans, 80% of whom are female.
With the right treatment, symptoms will often improve.
Types of POTS
There are three main types of POTS. In some cases, they can overlap and occur at the same time.
Types of POTS include:
- Hypovolemic POTS — caused by low circulating blood levels.
- Neuropathic POTS — caused by damage to the peripheral nerves that manage how certain blood vessels expand and contract.
- Hyperadrenergic POTS — caused by an overactive sympathetic (fight or flight) nervous system.
POTS causes
POTS isn't a disease. Instead, it's a group of symptoms from an underlying issue.
The symptoms happen when:
- There isn't enough blood volume circulating through your body, often due to dehydration or low red blood cell counts (anemia).
- Blood pools in parts of your body below your heart. This occurs when blood vessels can't constrict (tighten) properly and return the blood back up to your heart.
- You have elevated levels of epinephrine and norepinephrine (your fight-or-flight hormones).
Sometimes, the exact cause of POTS isn't clear. In many cases, an existing health issue that affects the ANS can trigger POTS.
Although doctors haven't found all the underlying causes of POTS, they believe the following conditions are involved:
- Amyloidosis — a disease in which abnormal proteins collect in tissues and organs.
- Anemia — low red blood cell counts.
- Autoimmune diseases like lupus, Sjogren's syndrome, and MS.
- Diabetes.
- Ehlers-Danlos syndrome — a disorder that affects your connective tissue.
- Genetic defects.
- Infections like mono, Lyme disease, and hepatitis C.
- Trauma from a surgery or recent pregnancy.
Some POTS symptoms, such as rapid heartbeat and sweating, are like those of anxiety disorders and panic attacks. But doctors don't think they're an underlying cause of POTS.
POTS risk factors and complications
Anyone can get this condition, but it's more common in:
- Women between 15 and 50 years old.
- Those with a family history of POTS.
- People suffering toxicity from alcohol, chemo, or heavy metal.
- People with vitamin and mineral deficiencies, such as iron deficiency anemia.
- Those with the underlying health conditions listed above.
POTS is not life-threatening and will not cause heart failure, but the symptoms can impact your life.
The most severe complication of POTS is trauma or an injury from falling or fainting.
How to prevent POTS
You can't prevent POTS, but you can ease symptoms by managing the underlying cause. In some cases, you may be able to prevent future episodes by making diet and lifestyle changes.
If you have symptoms, talk to your PCP. They can refer you to a specialist to find the cause and the best treatment plan.