What is Postural Orthostatic Tachycardia Syndrome (POTS)?
Postural Orthostatic Tachycardia Syndrome (POTS)
Postural orthostatic tachycardia syndrome, or POTS, is a form of dysautonomia.
Dysautonomia is a group of disorders that affect the autonomic nervous system. This system controls vital automatic functions such as heart rate, blood pressure, breathing, digestion and many other reflexes the body depends on.
In POTS, the body has trouble making the automatic adjustments needed when you change position. When you go from lying down to standing, gravity pulls blood toward your feet. Normally, the autonomic nervous system tightens blood vessels so blood keeps flowing back up to the brain. In POTS, these reflexes don’t work well, and blood flow to the brain can drop.
The body normally speeds up the heart to make up for this. In POTS, the heart rate rises much more than normal. A very fast heart rate may give the heart less time to fill with blood between beats, which can reduce blood flow to the brain even more. People with POTS often feel dizzy or lightheaded when standing, and some faint, which can lead to injuries from falls.
POTS should be diagnosed and managed with your physician, since other heart and medical conditions can cause similar symptoms. Call 911 if you have chest pain, severe shortness of breath, fainting with an injury, or fainting during exercise.
How Common Is POTS?
POTS affects an estimated 1 to 3 million Americans. It is most common in women and girls between the ages of 15 and 50, but it can also affect men and younger teens (1).
What Causes POTS?
POTS happens when the body can’t properly manage blood flow and blood volume during changes in position. The reason this happens is different from person to person (2), and many people have more than one contributing factor. Common types of POTS include (3):
Neuropathic POTS, linked to damage to the small nerve fibers that help control blood vessels.
Hyperadrenergic POTS, linked to high levels of stress hormones such as norepinephrine.
Hypovolemic POTS, linked to low blood volume.
Secondary POTS, which develops along with another condition, such as an autoimmune disease.
POTS can also occur after a concussion or traumatic brain injury and can be part of post-concussion syndrome (4).
Because the right approach depends on the cause, it’s important for each person with POTS to have a thorough evaluation, including a neurological assessment.
What Are the Symptoms of POTS?
POTS symptoms vary from person to person. They may include severe, long-lasting fatigue; lightheadedness or dizziness when changing position; fainting; nausea and vomiting; headaches; “brain fog,” or trouble thinking and focusing; heavy sweating; a pounding or irregular heartbeat; and pale skin or discolored hands and feet. Not everyone has every symptom, and other symptoms are possible. Symptoms often get worse in warm environments, when you haven’t had enough fluids, or after standing for a long time (2).
How Is POTS Diagnosed?
POTS is usually diagnosed with a tilt table test or a standing test, in which heart rate and blood pressure are measured while lying down and while upright (5).
The accepted criteria for diagnosing POTS include (6):
A sustained heart rate increase of at least 30 beats per minute within 10 minutes of standing or being tilted upright (at least 40 beats per minute in people ages 12 to 19).
No significant drop in blood pressure when upright (a drop of more than 20/10 mmHg would point to a different condition, orthostatic hypotension).
Symptoms of feeling unwell when upright that improve when lying down, lasting for several months.
Other possible causes of a fast heart rate have been ruled out, such as panic attacks, pain, exercise, caffeine, alcohol, certain medications, anemia, dehydration and thyroid problems.
What Happens in the Brain With POTS?
When the brain doesn’t get enough blood flow, many symptoms can appear. Your brain uses a great deal of energy, and when its supply is disrupted, many brain functions can be affected (7). Simple thinking tasks can feel like huge challenges, and simple physical tasks can be exhausting. Managing emotions can become very difficult. Nearly everything your brain does depends on steady blood flow, so when that system struggles, almost everything can feel like a struggle (8).
The Inner Ear’s Role in Blood Pressure
Your inner ear does more than help you balance. Through a reflex called the vestibulosympathetic reflex, signals from your inner ear reach blood pressure control centers in the brainstem and help adjust blood pressure and heart rate when you change position. This reflex responds to head movement before blood pressure has a chance to fall, while the baroreceptor reflex, which senses blood pressure in the large arteries, takes a second or two to catch up. That head start matters when you stand up quickly (9).
To use inner ear signals well, the brain has to clean them up. The inner ear’s motion sensors, the semicircular canals, give an imperfect signal, and its gravity sensors, the otoliths, can’t tell the difference between tilting your head and moving in a straight line. The brainstem and cerebellum solve these problems with a process called velocity storage, which combines and smooths these signals to estimate how your head is really moving and which way is down (9).
A 2022 study in the Annals of Clinical and Translational Neurology looked at 53 people with vestibular syncope, meaning fainting triggered by vertigo (10). More than a third had repeated episodes, and about 13% had potentially life-threatening injuries from falls. Abnormal inner ear tests were common, including abnormal head impulse tests in 31%, and about 1 in 5 also had orthostatic hypotension. The researchers proposed that when velocity storage produces a false sense of motion, the brain may adjust blood pressure for a position change that never happened. The baroreceptor reflex can then overcorrect, slowing the heart and dropping blood pressure, which can lead to fainting (10, 11).
Vestibular syncope is not the same as POTS. But this research shows that the inner ear, brainstem and cerebellum are part of the system that keeps blood flowing to your brain when you stand, and that problems in how the brain processes motion and gravity can contribute to autonomic symptoms. This is a core part of how we approach POTS.
That’s why we measure these systems so carefully. Videonystagmography (VNG) records eye movements that reflect how the brainstem and cerebellum are processing inner ear signals, including velocity storage. The video head impulse test (vHIT) measures how well each semicircular canal is working. CAPS computerized posturography shows how well your brain uses inner ear, visual and body-position information to stay upright.
How Is POTS Usually Treated?
There is no established cure for POTS. It is usually managed with lifestyle changes, such as increasing fluids and salt when recommended by a medical provider, wearing compression garments and following a gradual exercise program. Some people also benefit from medication (12). These treatments can help many people manage their symptoms.
How the NeuroRescue Program Can Help
Our care is designed to work alongside your physician, cardiologist and other providers, never in place of them. Please don’t change or stop any medication, or make changes to salt or fluid intake, without talking with your medical provider.
One of the brain’s most important jobs is figuring out where you are in the world. It uses your inner ear to sense where your head is in relation to gravity and how it’s moving, your muscles and joints to sense where your body is and what it’s doing, and your eyes to sense where you are in relation to everything around you. Your brain combines all of this into a picture of where you are, so you can respond to the world around you.
Your brain organizes this information as a set of maps: a vestibular map from your inner ear, a body map from your muscles and joints, a visual map from your eyes, and others. These maps need to agree with each other about where you are.
In some people with POTS, these maps may not match. Your eyes, inner ear and body may be sending different messages about where your head is in relation to gravity. Your inner ear also helps your body adjust blood pressure when you change position (9). When you go from lying down to sitting or standing, mismatched signals may make it harder for your brain to adjust blood flow to your head (8). Eye movement exercises and related therapies can activate brain and brainstem areas involved in autonomic control (13).
Our approach is to first work on improving how your visual, vestibular and body-position systems function on their own. Then we gradually train them together in different positions relative to gravity, with the goal of helping your nervous system respond more appropriately when you change position.
Depending on your needs and test results, your program may include specific eye exercises (14), vestibular therapy (15), electrical stimulation (16), light therapy, also called photobiomodulation (17), and exercises in a virtual reality environment (18). The therapies we recommend are always chosen based on your testing and exam findings.
How the NeuroRescue Program Works
Your NeuroRescue Program begins with your Discovery Day. We start with a detailed history of your condition and your life on a timeline. This helps us understand the factors that may have contributed to where you are now, and identify related conditions that may be making it harder to move forward.
We measure how your visual, vestibular and balance systems are working through computerized analysis of your eye movements, inner ear reflexes and balance under different conditions. Our testing includes videonystagmography and saccadometry to measure several types of eye movements, the video head impulse test to measure inner ear reflexes, and CAPS computerized posturography to assess your balance under different sensory conditions. We also use NeuroSensoryMotor Integration testing to evaluate hand-eye coordination and cognition, and Virtualis testing to assess dynamic eye tracking and your perception of vertical in a virtual reality environment.
We combine this with a thorough physical and neurological exam of your sensory, motor, autonomic and cognitive systems. We also review any relevant lab work, imaging and prior testing, and integrate it with our findings.
Together, this helps us understand which parts of your nervous system are working well, which are struggling, and how quickly they tire. We use that information to design your personal NeuroRescue Program, aimed at improving function in the systems that need support and helping them work together. Our testing also helps us decide when to push and when to let you rest. That matters in POTS, where pushing too hard can leave you wiped out for days.
Our goal is to help you build tolerance for being upright, so you can stand, think and get through your day with more energy and less dizziness.
Your Next Step
Living with POTS can be exhausting, and it’s often invisible to the people around you. You don’t have to keep pushing through alone. To find out if the NeuroRescue Program is right for you, contact one of our patient care coordinators to schedule your Discovery Day.
It’s never too late to take the next step.
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