Self-diagnosing is oftentimes frowned upon in the medical community due to a lack of accuracy, external influences, and biases. However, because of what the healthcare system unfortunately has become, overlooked individuals suffering from unexplained symptoms may turn to the internet. This person may know a person with POTS or see something on social media (usually TikTok nowadays), look it up, discover that their symptoms sound like POTS, and decide, “This is it!”
I want to preface that I’m hardly the one to criticize the idea of self-diagnosis. Because of the neglectful healthcare system and rotation of doctors, I, too, turned to the internet and discovered POTS. This was back in 2016; there was no representation in the media and POTS was basically unheard of. When you looked up palpitations in combination with dizziness and headaches, dysautonomia did not automatically come up compared to how it is now. After being dismissed by doctors multiple times and being told “That’s too rare; there’s no way you have it,” I was formally diagnosed at the Mayo Clinic a few months later.
All this being said, there’s a right way to do this and methods you should follow in order to gain a full understanding, and unfortunately, most people don’t go about it that way.
POTS should never be diagnosed on the basis of symptoms alone. Symptoms can be a clue, but lots of these symptoms are pretty nonspecific: fatigue, lightheadedness, vertigo, brain fog, general malaise, difficulty exercising, sleep disturbances, gastrointestinal problems, etc. While more unique symptoms are better clues, they are still inconclusive and cannot confirm the diagnosis. Additionally, there are multiple conditions that may produce POTS-like symptoms that must be ruled out beforehand.
What are the Diagnostic Criteria?
The only way to confirm a POTS diagnosis is by satisfying the diagnostic criteria and all criteria must be met.
Sustained heart rate increase of ≥ 30 beats per minute within 10 minutes of upright posture.
If the patient is under 19 years old, an increase of ≥ 40 beats per minute is required.
Absence of significant orthostatic hypotension (magnitude of a blood pressure drop ≥ 20/10 mm Hg).
Very frequent symptoms of orthostatic intolerance that are worse while upright, with rapid improvement upon returning to a supine position. Symptoms vary between individuals, but often include lightheadedness, palpitations, tremulousness, generalized weakness, blurred vision, and fatigue.
Symptom duration of ≥ 3 months.
Absence of other conditions that could explain sinus tachycardia.
So what exactly does all of this mean?
POTS Criteria Explained
1. Sustained heart rate increase of ≥ 30 beats per minute within 10 minutes of upright posture (if the patient is under 19 years old, an increase of ≥ 40 beats per minute is required).
This is the orthostatic tachycardia part of POTS. By definition, you cannot have POTS without it. If you’re just experiencing the classic vague symptoms and have no idea what your heart rate is doing when you go from lying or sitting to prolonged standing, you’re missing one of the most important pieces of information.
So how can you measure your heart rate and determine whether you may fit this criterion?
The gold standard for an official POTS diagnosis is a tilt table test. A positive diagnosis is made when the heart rate increases at least 30 beats per minute after a ten-minute tilt from supine (laying) to standing. Alternatively, you can conduct a “poor man’s tilt table test” (PMTTT) in your home that can give you a feel for your tolerance to vertical posture.
Unfortunately, there isn't a definitive or clear definition of what sustained actually means which is often incredibly confusing to people suspecting POTS. Some argue that it's defined as once your heart rate reaches an increase of 30+ bpm it must remain elevated for the rest of the test. Others argue that you must have more than one consecutive reading of a 30+ bpm increase at least one minute apart.
It's totally normal for non-POTS people to experience an increase in heart rate when they stand up. Because nearly a third of your blood is pulled downward by gravity when you stand up, the autonomic nervous system (ANS) goes into overdrive to pump that blood back up to your head. However, compared to POTS and orthostatic intolerance, the ANS is unable to maintain that equilibrium. For example, a "normal" person's resting heart rate may be 75, they stand up and it reaches 90, but then drops down again and is relatively similar to their original resting heart rate.
How to Conduct a Poor Man’s Tilt Table Test?
Lay down for approximately 5-10 minutes with no fidgeting or talking. You must be perfectly relaxed and comfortable.
Record your heart rate as a relaxed, baseline reading.
Then, stand up with no fidgeting or talking. You must not shift your weight from leg to leg and you must be as still as a statue (this can skew the results).
Record your heart rate after 5 minutes, and again 5 minutes later (at the 10-minute mark).
** Note: the results of the poor man's tilt table test I provided was during a flare and is only being used as an example.
You can see that my heart rate at the beginning is roughly around 86 bpm. When non-POTS individuals go from sitting to standing, their heart rate is momentarily a little higher than their resting/baseline heart rate due to the normal compensation for gravity and change in posture, however, it quickly normalizes.
Instead of leveling out, my heart rate shoots up to 147 within seconds; this is not normal. My body is struggling to keep blood going to my head, so it’s revving up to compensate. While my heart rate eventually decreases to around 128 bpm, it remains high and continues to climb the longer I remain upright. At the end of the 10-minute test, my heart rate reached 162; a 76 bpm increase with a max of 172. While this isn’t required a part of the poor man’s tilt table test, I included how my heart rate dramatically decreased after returning to a supine position as well.
Here are my results for those who may not be able to read the picture:
Baseline: 86
5 minutes: 138
10 minutes: 162
Max: 172
30 seconds after laying down: 109
The directions for the PMTTT can help identify evidence of broken hemodynamics and/or an overreaction of the ANS to standing, it may be useful to measure your heart rate and blood pressure every minute after standing for 10 minutes to have a broader picture.
Exceptions?
The Canadian Cardiovascular Society set a minimum supine heart rate of 60 bpm to prevent the diagnosis of POTS being made in a patient with a low resting heart rate that increases to a normal level on standing. Now, I was unaware of this so I can only assume what this may mean. This means that if your heart rate lying down is 56 and upon standing increases to 92 and is sustained, you would not meet their criteria for POTS. If the resting heart rate is lower than 60, the individual must meet an increase of 60 bpm to be diagnosed (i.e. resting bpm 56 to 116).
Additionally, the American Autonomic Society states that if a patient doesn’t reach an increase of 30 bpm upon standing, but it reaches or goes above 120, POTS may be suspected (i.e. resting bpm 98 to 120). I don’t know how entirely accurate this is, but I do know instances in which practitioners have told people that if they don’t meet or exceed 120 then they don’t have POTS (which is inaccurate).
Also...
Not every PMTTT (or TTT) is going to create the same numbers. There may be days when you're feeling better than normal, or you have your average amount of symptoms, or you're in a flare (increase or worsening of your typical symptoms). My results are never exactly the same - some days my heart rate only reaches 130 when standing, other days it'll be 150, and then sometimes it'll be 172. If your doctor does conduct a PMTTT and it doesn't exactly meet this part of the diagnostic criteria, your doctor may diagnose you with something called PSWT (postural symptoms without tachycardia) and you should eventually be reevaluated at a later date.
2. Absence of significant orthostatic hypotension (magnitude of a blood pressure drop ≥ 20/10 mm Hg).
This is a contentious topic as it’s a little difficult to understand, especially for the layman. Orthostatic hypotension (OH) is both a diagnostic label and a descriptor. In the diagnostic criteria for POTS, they’re describing classic and sustained orthostatic hypotension which has separate criteria and can also cause orthostatic tachycardia (OH is another kind of dysautonomia).
This is what makes this criterion tricky, especially for practitioners who aren’t very well-versed in POTS. Even more so, this makes patients incredibly confused and frustrated because orthostatic hypotension is quite common in the POTS community. However, there are other orthostatic reductions in blood pressure: a transient initial OH immediately after standing that quickly resolves, and a delayed OH that comes on later. People also often fail to include the terms classic, sustained, initial, and delayed when describing the type of orthostatic hypotension they experience, and this especially causes arguments.
If sustained orthostatic hypotension and orthostatic tachycardia occur simultaneously, we ought to assume that the former is causing the latter. In this case, doctors will treat the OH and see if the orthostatic tachycardia resolves. Another reason why this criterion is rather confusing is because quite a few medications used to treat POTS are also used in treating OH. These often include midodrine, fludrocortisone, and desmopressin which are commonly used to increase blood pressure. Because of this, it’s often misunderstood and the two are confused by both patients and doctors.
I've included an example of my blood pressure commonly seen in the subtype hyperadrenergic POTS (an increase in BP).
3. Very frequent symptoms of orthostatic intolerance that are worse while upright, with rapid improvement upon returning to a supine position. Symptoms vary between individuals, but often include lightheadedness, palpitations, tremulousness, generalized weakness, blurred vision, and fatigue.
This criterion can also be a bit tricky as we may not say “Aha! This is what happens when I’m standing!” until we see the criteria and think about it. Practitioners and patients may also get this confused but for different reasons. When doctors hear an individual is dizzy, fatigued, and experiencing palpitations upon standing, many are quick to blame it on deconditioning, dehydration, and unfortunately even blame it on weight. Individuals suspecting POTS may also possibly get this criterion confused. Much of the population may experience some level of fatigue and lightheadedness if they’re standing outside in the heat for long periods of time or if they’ve worked out strenuously. However, this explains symptoms upon just simply standing and completing very minor tasks.
When I was first experiencing my POTS symptoms, I was incredibly active. I swam competitively for years and regularly swam for 2.5 hours including quite strenuous dryland (lifting weights, circuit training, running, etc). Yet, I was having difficulty and lightheadedness getting up off the couch to use the restroom. I would get winded and need to catch my breath after walking up a flight of stairs. I became weak and had blurred vision while brushing my teeth or putting my hair up.
Despite swimming in large meets across the country and being quite decorated, doctors still blamed my symptoms on deconditioning. It was also not uncommon for these practitioners to blame these symptoms for a psychiatric condition like anxiety or depression. The shortness of breath, lightheadedness, weakness, and blurred vision I was experiencing was an orthostatic symptom, not a sign I was out of shape.
Other common symptoms people talk about are sweating profusely or not at all, temperature dysregulation (becoming unnaturally hot or cold), blood pooling (bulging veins in the hands, arms, and feet), and dependent acrocyanosis (purple legs and/or hands when standing, sometimes causing a heavy, burning, or itching sensation).
A common misconception about POTS is that syncope, or fainting, is needed in order to be diagnosed with POTS (only 30% of POTS patients actually faint). Oftentimes, most people only experience the feeling of “wooshiness” (the best I can describe this is it’s similar to vertigo), tunnel vision, feeling like your head and shoulders are being pushed down, and black or white spots in your field of vision. This is what’s known as presyncope, or the feeling that you’re going to faint. Unfortunately, some doctors believe this to be true, but syncope is not part of any of the criteria, so it doesn’t matter if you faint or not.
Symptom duration of ≥ 3 months.
Most people, at least once in their life, will have feelings of lightheadedness, blurry vision, general malaise, weakness, etc. from things such as common colds or the flu. The main difference between this and the symptoms people with POTS experience is that where the general population may experience these for a couple of days, these symptoms are chronic and usually experienced on a daily basis.
Absence of other conditions that could explain sinus tachycardia.
This is where self-diagnosis often fails. This is where you need to see a doctor to order preliminary bloodwork to rule out the usual suspects like anemia, thyroid disease, endocrine disorders, autoimmune disease, pheochromocytoma, etc. You also must rule out cardiac and even lung conditions, especially when lightheadedness, palpitations, and shortness of breath are major concerns. In order to check the integrity of the heart itself, it’s typical to have an echo, or echocardiogram, (ultrasound of the heart), stress test, and a Holter monitor (a small ECG-like machine attached to your chest worn for 24 hours to a month or more to rule out arrhythmias).
Often all of this testing will come back “normal” which is confusing to both doctors and patients. While doctors feel like they’ve ruled out all of the typical culprits for these symptoms, those in search for a diagnosis are frustrated because they know the symptoms they’re feeling are real. It’s usually assumed that a Holter monitor would be extremely helpful because it’s continuously tracking your heart rate but the only thing those reading the results are looking for are truly cardiac-related conditions like conduction problems, PVCs, ectopic beats, heart blocks, etc. While tachycardia may be noted, it’s difficult to know whether or not that tachycardia is from simple things like standing up, brushing your teeth, putting your hair up, making dinner or if you’re working out or doing something strenuous so it’s often overlooked.
The Main Takeaway...
Some people just aren't able to receive a formal POTS diagnosis because of how the healthcare system is and they can't financially afford to pay out of pocket to see a specialist. But if you're seeing a general or primary care practitioner, please try to bring up POTS with evidence of why you suspect this diagnosis (PMTTT results, symptom trackers, etc.). This diagnostic journey is unfortunately still incredibly hard for many people and takes so much longer than it should. If everything has been ruled out and POTS is still a concern, many people will turn to the recommended nonpharmacological treatments and lifestyle changes to help manage symptoms.
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