MICHAEL B. GOODKIN, MD, FACC
Postural orthostatic tachycardia syndrome (POTS) is a problem of the autonomic nervous system that often manifests with cardiac symptoms. Almost all patients have orthostatic intolerance, the inability to tolerate standing still due to blood pooling in the legs and pelvis. In orthostatic intolerance, the heart rate increases but the blood pressure drops by less than 20 mmHg or actually increases with standing. Symptoms get worse the longer the patient stands. The heart compensates by increasing its rate but cerebral blood flow decreases with resultant lightheadedness and syncope. Patients are extremely fatigued and have brain fog (they can’t think straight). Exercise intolerance, headaches and sleep disturbances are usually present. GI symptoms can be terrible with gastroparesis and bowel hypomotility. One third have Ehlers Danlos syndrome while 10% have mast cell activation syndrome.
Finding good care is not easy for patients. 50% of patients travel more than 100 miles for care by a cardiologist or neurologist. Before I had many POTS referrals, I saw a new POTS patient every 3-4 months. At that rate, the average cardiologist or neurologist will see over 100 POTS patients in their career.
As practitioners, we need to understand this neurological condition so that we can appropriately diagnose and treat our patients. Physicians need to be able to treat the orthostatic intolerance and tachycardia that are hallmarks of POTS. If you suspect POTS and the patient has an abnormal standing test, you can refer them to a general cardiologist, cardiac electrophysiologist, or a neurologist. Electrophysiologists have traditionally been hailed as the POTS experts. However, general cardiology and neurology need to handle some of the burden. It requires some practice, but skill can be gained quickly.
Consider POTS when your patient is under age 50 and presents with:
- Lightheadedness, especially while standing
- Syncope or near-syncope
- Shortness of breath
- Excessive fatigue
- Nonspecific symptoms that don’t make sense on the surface
- No obvious underlying pathology
If you suspect POTS, conduct a standing test (poor man’s tilt table) in your office
- Lay the patient down for 5 minutes and take the BP and HR.
- Have them stand up in the middle of the room and take their HR and BP at 2,5 and 10 minutes.
- If the heart rate increases by 30 beats per minute or to 120 beats per minute or above at any point during the standing portion of the test, your patient has POTS (40 beats per minute in children).
- Most patients will become positive early. If they do, end the test.
- Some patients will get lightheaded and very uncomfortable without meeting criteria for POTS. Let them sit down too. These patients might be positive on a different day or on a tilt test. A young person who can’t stand 10 minutes due to lightheadedness has a serious problem, and I treated them like the heart rate positive patients.
- Some patients have a delayed fall in blood pressure (delayed orthostatic hypotension). Some have little HR or BP response but insist on sitting down because they feel awful. In my experience about 20% of orthostatic intolerant patients are HR negative. I have generally not sent them for tilt testing but would not argue with people who do.
Standing tests can be done routinely during office visits, including standing patients with known POTS to monitor treatment effectiveness. The results from visit to visit may be variable. Patients hate the full tilt table tests because they have to go off medications, and the tilt table tests are often unnecessary when a standing test in the office will suffice.
We need to refer patients to the appropriate consultants to improve their quality of life.
- Iron deficiency. Using a ferritin cutoff of 40, 60% were iron deficient although few were anemic. All were treated with IV iron and almost all felt better independent of hemoglobin. That is the general experience of hematologists treating iron deficiency.
- Red blood cell depletion. For unknown reasons most patients are volume depleted. In a study by Dr. Levine, the average red cell mass was down 20%. Iron deficiency can lower red cell mass. We measured red cell mass and plasma volume after iron replacement. It was down more than 10% in about 70% of POTS patients we tested. Of those, about 60% responded well to procrit or aranesp. There is a black box warning on procrit to a Hb greater than 11 for patients with cancer or on dialysis. Procrit can cause blood clots, heart attack, stroke and death.
- Hypomobility of the colon
- Nausea and vomiting
- Adrenal insufficiency. Conduct a fasting cortisol. Tenascin X is important for collagen function. The gene for Tenascin X overlaps the gene for 21 hydroxylase, the rate limiting enzyme in cortisol synthesis.
- Hypopituitarism, especially when taking narcotics long term
- Autoimmune thyroid abnormalities
- Chiari I malformation
- Tethered cord
- Craniocervical instability
- Small fiber neuropathy
- Complex regional pain syndrome
- Ehlers-Danlos syndrome. In POTS patients, part of the office visit should involve asking about joint hypermobility. It’s important because these patients are harder to treat and are prone to joint and spine abnormalities. Ehlers-Danlos Syndrome now known as Joint Hypermobility Spectrum Disorder has 14 types but the vast majority of patients have hypermobile EDS, the only type for which the genetic abnormality has not yet been found.
- Autoimmune disorders are present in 20% of POTS patients.
- Allergy and Immunology:
- Mast cell activation syndrome
Treatment consists of
- As much sodium and fluids the patient can tolerate
- IV fluids. 2 liters of saline can often turn things around. Continuous IV fluids work great but usually lead to line sepsis.
- Compression garments like waist high elastic stockings or an abdominal binder are often helpful
- Raising the head of the bed makes patients make less urine during the night and some people think offers some “tilt training”
- Exercise training can cause dramatic improvement. Patients do recumbent bicycle, rowing machine, swimming and leg resistance training for about 6 weeks before graduating to upright exercise.
- Medications include
- Beta blockers at low doses, e.g. Propranolol 10-20 mg twice per day
- Concerta, 36-54 mg per day
- Fludrocortisone, 0.1-0.2 mg per day
- Mestinon, 60-120 mg 3 times per day
- Midodrine, 15 mg 3-4 times per day
- Modafinal for cognitive dysfunction
- Naltrexone, low dose
- Vyvanse, 30-70 mg twice per day. They act as vasoconstrictors and help with fatigue, cognitive dysfunction and orthostatic intolerance
Other Treatment Options
- IVIG. The current thinking is that POTS is antibody related. 20% have an identifiable autoimmune disorder. Several kinds of autonomic receptor antibodies have been identified although testing is not generally of clinical value. Half the patients have small fiber neuropathy on skin biopsy. A randomized trial of intravenous immunoglobulin is ongoing in Dallas. Patients can take IVIg 5 hours a day, 5 days a week, every 4 weeks. It’s useful but unwieldy.
- Cranial osteopathic manipulation. A significant proportion of POTS may be caused by biomechanical problems, mostly injury. Osteopaths find the problem with their hands and have techniques to release the tissues. Exactly how it works is a mystery. About 40-45% of adults have a moderate response with occasional “miracles.” Children respond much better. If it hasn’t worked in 5- 6 visits, it won’t work. There is no morbidity from the treatment. Practitioners can be found at www.cranialacademy.org. Choose an osteopathic physician with at least 80% of their practice that is cranial.
- Somatosensory therapy. This therapy is done primarily by chiropractic neurologists and is referred to as functional neurology. Dr. Kevin Lasko believes POTS is caused by abnormal sensory processing and treats it primarily with cranial nerve stimulation.
- Surgery. If the patient has EDS and is floundering with treatment, they may have Chiari I, tethered cord and/or craniocervical instability from ligamentous laxity in their neck causing a retroflexed odontoid process. Neurosurgeons Fraser Henderson in Chevy Chase, Maryland and Paolo Bolognese in Garden City, NY are the most expert in treatment of these conditions. Craniocervical instability is relatively unknown the POTS community, yet the vast majority of these patients have POTS.
Sometimes no matter what you do the patient will do poorly. It’s the main reason physicians shy away from POTS patients, the feeling of futility. However, these patients deserve our attention and care as we work to improve their overall quality of life.