Updates in Postural Orthostatic Tachycardia Syndrome: Novel Program Provides Comprehensive Treatment

In this interview, EP Lab Digest speaks with Tae Chung, MD, director of the Johns Hopkins Postural Orthostatic Tachycardia Syndrome (POTS) Program in Baltimore, Maryland. Dr Chung is an assistant professor of Physical Medicine and Rehabilitation and Neurology at Johns Hopkins University.

Tell us about your medical background. What interested you about this field?

My residency background is in physical medicine and rehabilitation, but after my residency, I did my fellowship in neuromuscular medicine in the neurology department. It is a combined specialty between physical medicine and rehabilitation, and neurology. In my clinical practice, I see a lot of patients with various neuromuscular disorders affecting the peripheral nervous system. Currently, I am focused on treating patients with POTS and myositis (an inflammatory muscle disease).

How and when was the POTS program established at Johns Hopkins?

I have been seeing POTS patients since I joined the faculty in 2014. Because of my background in physical medicine and rehabilitation, I had easier access to physical therapists and rehabilitation therapists. I started the multidisciplinary POTS Program in 2017, in collaboration with one of the therapists.

What can you tell us about the center and your role? Describe the multidisciplinary team of experts and specialists involved in care at the clinic.

Once we started this multidisciplinary clinic, we quickly began seeing a lot of patients, so we hired a nurse practitioner and some other attendings. We are also lucky to collaborate with other experts at Johns Hopkins, including cardiologists, neurologists, and psychologists.

We are all involved not only in the diagnosis of POTS, but also in rehabilitation and long-term care, because POTS symptoms can be very debilitating. Our physical therapy protocol for POTS is unique. It is not like typical physical therapy, as not a lot of physical therapists are trained in POTS. In our program, we have specific POTS therapists who we meet with weekly to discuss and further develop our protocol. We also consult with our neurology, cardiology, and psychology departments to bring awareness about POTS, as it is often mistaken for other disorders. A lot of times, patients start with another specialist when seeking a diagnosis, and they are later referred to our program.

How is POTS defined?

POTS is primarily diagnosed through a tilt table test or by checking the patient’s orthostatic vital signs on active standing. If the patient’s heart rate increases by more than 30 bpm (40 bpm in pediatric patients), or over 120 bpm, within 10 minutes of standing, accompanied by reproduction of their typical symptoms, they can typically be diagnosed with POTS. However, other cardiac conditions and arrhythmias need to first be ruled out to confirm this is a neural dysregulation of the cardiovascular system. It is important to recognize there are unique symptoms, such as chronic fatigue, brain fog, and gastrointestinal (GI) symptoms, in addition to orthostatic intolerance.

What is known about the prevalence of POTS?

It is important to first acknowledge that POTS is a heterogeneous clinical syndrome. As such, it is difficult to define the overall prevalence, but it is thought to be very common, maybe much more so than people think. Statistically, POTS is estimated to affect up to 0.5%-1% of the population.

Tell us about clinical evaluation of patients with suspected POTS.

There are 2 main approaches for clinical evaluation of POTS. The first part of the evaluation is to rule out mimicking conditions. In this approach, a cardiac evaluation is needed to ensure the patient’s heart is normal and exclude other diagnoses. It is important to rule out cardiac arrhythmia, heart failure, or other heart conditions, which may have very similar presentation. Patients often present with nonspecific symptoms such as chronic fatigue and brain fog, and occasionally, patients are referred for evaluation of thyroid problems or other chronic conditions. However, the combination of symptoms is very unique in POTS patients, so if the pattern is recognized, it will narrow down some differential diagnoses.

The second part of the evaluation is to rule in evidence of autonomic dysfunction. This can be challenging, as there are not many standardized diagnostic tools for the autonomic nervous system. However, for those patients presenting with typical symptoms, including young patients who are not suspected to have any other conditions such as heart failure, then orthostatic vital checks and monitoring of heart rate changes in different positions can be sufficient for us to begin treatment.

If further diagnostic evaluation is needed, we perform a nerve biopsy to try and look at the small nerve under the skin. This is in addition to autoimmune function testing and tilt table testing, depending on the clinical situation.

How do you educate your patients about POTS?

Patient education is important. During our current patient visits, we spend about half of the time on education, including discussions on lifestyle changes and other treatment options. In my experience, most of the patients in our clinic are in their 20s and 30s—we rarely see patients older than 50 years. Therefore, these patients are often internet savvy and have already looked online for more information on POTS.

During the first clinical visit, I review the pathophysiology and symptoms of POTS. I want my patients to understand that it is not just about lifestyle changes or how much water they drink. Their treatment will be more effective when they understand the fundamental pathophysiology to help better manage their symptoms.

What pharmacologic and nonpharmacologic options have demonstrated to be effective in the treatment of POTS?

There are a lot of pharmacologic and nonpharmacologic interventions that are very effective. However, because POTS symptoms are so dynamic, there is no one medication that can cure all. One of the reasons that POTS is so debilitating for patients is because it affects vasomotor dysfunction. Since blood flow dysregulation can affect everywhere in the body, including the brain, muscles, and GI system, POTS symptoms can affect more than one area of the body. Therefore, there is no one drug or treatment that can cure or even address the basic pathophysiology at this point.

In pharmacologic intervention, a lot of drugs are targeting specific symptoms, but because symptoms can change over time, we have to be proactive and flexible in our approach. In general, because of the multisystem nature of POTS symptoms, patients often present with multiple symptoms and end up seeing many different specialties such as gastroenterologists or neurologists. This typically results in polypharmacy, which is a common problem in POTS patients. Oftentimes, simply evaluating a patient’s medication list and eliminating some of their medications can actually improve their symptoms. In our clinic, we try to collaborate with other doctors and prevent polypharmacy, which can be very challenging.

Regarding nonpharmacologic interventions, I believe physical exercise is one of the most beneficial options for patients. If and when it works, it is the most powerful intervention. There are a lot of different theories why, but I think it provides the most significant amount of blood volume expansion over time. However, a lot of POTS patients experience a postexercise flare or malaise. If they do more than they can handle, they usually experience a flare or setback. It is critical to advance their training level very slowly. Oftentimes, this takes more than several months to a year. Most patients try their best, but it can be frustrating for them, especially if they do not understand exercise intolerance or postexercise flare. So, it is really important to educate patients about this, and at the same time, reassure them that exercise can help. Even starting small and building their tolerance over time will help them do much better. Again, it is not a cure, but it is better than some of the currently available drugs and interventions.

What is the long-term prognosis for patients diagnosed with POTS?

As a clinical syndrome, the long-term prognosis is not known and may differ depending on the subtypes. There are no good long-term studies on prognosis. Literature suggests that POTS is a chronic condition. There is a high index of suspicion for autoimmunity in many cases. As with other autoimmune neurological conditions, POTS symptoms can wax and wane over time. Even without treatment, some symptoms may improve, but flare up again later.

How has the treatment approach to POTS evolved or advanced over time?

While effective pharmacologic and nonpharmacologic interventions for POTS have evolved over time, I think what we are still struggling with is POTS awareness. Once patients are able to start treatment with a POTS clinic or visit a doctor familiar with POTS, they tend to do better. We are also seeing an influx of patients with post-COVID-19 POTS, so that has been a new opportunity for us doctors.

The second thing is increasing awareness about POTS as an autoimmune condition. As a neuromuscular doctor, I have tried certain interventions such as intravenous immunoglobulin (IVIG) therapy. However, there is currently no biomarker for autoimmunity in POTS, and I am very careful with trying IVIG, given the potential risks associated with the treatment. Future directions in treatment will include finding more biomarkers for autoimmunity and translating that into better treatment using immune-modulating drugs.

Has a link been found between COVID-19 and POTS?

A “link” can mean a lot of different things from a scientific standpoint, but at this point, there is a strong clinical suspicion that many characteristics of post-COVID-19 syndrome are consistent with those of POTS. For example, it has been well-recognized for many decades that POTS patients can experience chronic fatigue, brain fog, GI symptoms, exercise intolerance, and sleep problems, and post-COVID-19 patients can develop exactly the same symptoms. Due to lack of awareness, those symptoms are dismissed as being psychological in nature, but oftentimes, a simple orthostatic vital check can help in diagnosis of post-COVID-19 POTS. I suspect that there is a much  higher prevalence of POTS in the post-COVID-19 population than most people think.

How do patients typically present to the POTS clinic?

Most patients present with chronic fatigue and brain fogfog, in addition to many other symptoms. I would like to emphasize that the “classic” symptoms of POTS, such as palpitation and lightheadedness, are not typically their presenting symptoms. Over a short period of time, POTS patients adapt to those orthostatic symptoms. I have a lot of long-term POTS patients who don’t even realize when their heart rate goes above 150 bpm—they just feel a little discomfort, fatigue, or brain fog. That is why when a patient presents with chronic fatigue or brain fog, POTS is not the first thing that comes up in most doctors’ minds. Patients end up seeing multiple doctors before they finally visit a POTS clinic.

On average, how many patients are managed at the program on an annual basis?

In 2019, our team saw about 2500-3000 patients. However, with post-COVID-19 syndrome, we are beginning to see more patients on an annual basis.

Are pediatric POTS patients also treated at your clinic?

Yes, one of our attending doctors is a pediatric specialist, so she is focused on that patient population.

Are alternative therapies such as yoga effective in reducing POTS symptoms?

Absolutely, that is an important nonpharmacologic intervention. Yoga, meditation, and mindfulness techniques can decrease sympathetic activation and calm patients.

Do you collaborate with other comparable POTS programs around the country as well?

Yes, we have a virtual POTS meeting every Thursday. It started as an internal meeting with Johns Hopkins providers, but has become more of a national meeting. We have people from Vanderbilt, New York University, and the National Institutes of Health. We share cases and lectures, and are planning on research collaborations as well.

What is most commonly misunderstood about POTS?

Patients are often frustrated because doctors dismiss their symptoms as being psychological in nature. If a neurologic examination or magnetic resonance imaging shows the brain is completely normal, then by default, doctors sometimes assume that a patient’s brain fog is psychological because everything else was normal. There are not many good imaging or clinical tools to evaluate autoimmune function of blood flow issues, so it is often missed.

What further research is needed? Where is knowledge lacking?

There are still many gaps and barriers. This field is very young and just beginning to blossom. A better understanding of pathophysiology as well as better clinical tools are needed to approach these patients. We also need better biomarkers—that is actually one of the immediate gaps—a blood test would be helpful in showing doctors that there is something going on.

There also seems to be a genetic trait in POTS, as a lot of our patients have POTS in their family. While POTS may not specifically be a genetic condition, I believe there is probably a genetic predisposition in some families. This is one of the gaps in knowledge where more research is needed.

I believe that better understanding of POTS pathophysiology will lead to better treatment. Fortunately, information on the diagnosis and treatment of POTS is expanding every year. 

Disclosures: The author has completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Chung has no conflicts of interest to report regarding the content herein.