After compiling the big long post that will be broken into a few parts about why you need to find your POTS cause, I wanted to discuss what POTS really is.
There is so much confusion and debate between doctors, and amongst people on the support groups and blogs.
|This dude smokes POT(S)|
So what in the world is POTS?
You can print this out and bring it to your doctor if they are unaware, or share with anyone who may be confused on the subject. I would recommend only printing what is between the lines, not my silly pictures.
The most recent consensus definition of POTS by most of the lead researchers in the field is this:
"4.1. Definition: The postural tachycardia syndrome (POTS) is characterized by a sustained heart rate increment of ≥ 30 beats/min within 10 min of standing or head-up tilt in the absence of orthostatic hypotension. The standing heart rate for all subjects is often ≥ 120 beats/min. These criteria may not be applicable for individuals with low resting heart rates. For individuals aged 12–19 years the required increment is at least 40 beats/min. The orthostatic tachycardia may be accompanied by symptoms of cerebral hypoperfusion and autonomic overactivity that are relieved by recumbency.
4.2. Pathophysiology: The etiology and pathophysiology of POTS are unknown but are likely to be heterogeneous. The syndrome is associated with deconditioning, recent viral illness, chronic fatigue syndrome and a limited or restricted autonomic neuropathy. The differential diagnosis includes conditions that cause tachycardia, such as thyrotoxicosis, inappropriate sinus tachycardia and other
cardiac rhythm abnormalities, pheochromocytoma, hypoadrenalism, anxiety, dehydration, and medications (e.g., vasodilators, diuretics, and ß-agonists).
4.3. Epidemiology and clinical features: The prevalence of POTS is not known. The syndrome is more common in women. The orthostatic symptoms consist of lightheadedness, visual blurring or tunnel vision, palpitations, tremulousness, and weakness (especially of the legs). Other symptoms include fatigue, exercise intolerance, hyperventilation, shortness of breath, anxiety, chest pain, nausea, acral coldness or pain, concentration difficulties and headaches. On clinical examination, in addition to the heart rate increment, pulse pressure may be reduced and acral coldness may be present. Continued standing may lead to venous prominence, cyanosis and foot swelling. A hyperadrenergic state is present in some patients who have a resting tachycardia, sweating, and tremulousness."
Source: Consensus statement on the definition of orthostatic hypotension, neurally mediated syncope and the postural tachycardia syndrome. Freeman R et al. , Auton Neurosci. 2011 Apr 26;161(1-2):46-8. Epub 2011 Mar 9.
Here is the complete list of contributors: Roy Freeman, Wouter Wieling, Felicia B. Axelrod, David G. Benditt, Eduardo Benarroch, Italo Biaggioni, William P. Cheshire, Thomas Chelimsky, Pietro Cortelli, Christopher H. Gibbons, David S. Goldstein, Roger Hainsworth, Max J. Hilz, Giris Jacob, Horacio Kaufmann, Jens Jordan, Lewis A. Lipsitz, Benjamin D. Levine, Phillip A. Low, Christopher Mathias, Satish R. Raj, David Robertson, Paola Sandroni, Irwin J. Schatz, Ron Schondorf, Julian M. Stewart, J. Gert van Dijk
So - that is only what all these various researchers with all the differing definitions of POTS agreed upon. There are a few big names missing, like Dr.'s Grubb and Mathias, but this seems to be some sort of effort to come to an understanding of the minimum requirements for a POTS diagnosis, and to get the point across that blood pressure (BP) changes are not a requirement, and even includes the statement that POTS only occurs in the absence of a blood pressure drop. This still confuses me, because my understanding was that you can have POTS and orthostatic hypotension or NMS. I'm going to hypothesize that they are finding in patients with the drop in BP, it is a sign of something else going on, and doctors need to dig deeper than the typical causes of POTS. Or that "everyday doctors" that don't specialize in dysautonomia were ruling out POTS without a drop in BP. I plan to email a few of these doctors for clarification, hopefully someone will respond!
|The majority of POTS patients: good looking, young women. Who are told they have anxiety.|
POTS is a syndrome (a collection of symptoms, not a disease). If someone's heart rate increases at least 30 beats per minute (BPM) when standing, many times above 120 BPM, within 10 minutes, that is POTS. Some of the symptoms are relieved once laying down, but many are chronic and mimic other conditions. It has many causes, and affects mostly women. Certain dangerous conditions that mimic POTS or coincide with POTS need to be ruled out.
POTS does not include, by defintion, any changes in blood pressure, those are separate disorders. In fact, in the consensus statement, they say that you only have POTS in the absence of a drop in blood pressure. So if your doctor tries to tell you that you are fine and it's just anxiety because your blood pressure didn't drop, or because you are a young, healthy looking woman, show them the above statement, along with this statement about the difference between anxiety and POTS (and maybe get a new doc!).
See the post regarding Syncope and Neurally Mediated Syncope for more details on disorders related to dropping blood pressure and fainting.
As a side note - this was the first listing in Google when I typed in POTS, of course from that most reliable of sources, Wikipedia (insert sarcasm):
From Wikipedia, the free encyclopedia
|Look up pots in Wiktionary, the free dictionary.|
- Plain old telephone service, basic wireline telecommunication connection
- Postural orthostatic tachycardia syndrome, a medical condition
- Poverty of the stimulus, an argument in favor of innate grammar
- Protector of the Small, a series of fantasy novels
- The Path of the Shell, an expansion pack of the computer game Uru: Ages Beyond Myst
- Pacific Organized Track System, airways between Japan/Southeast Asia and the US mainland
- Plain old television service, or over-the-air TV
Oh, and this guy IS SO NOT POTS:
And if you haven't seen it, here is a PG-13 video I made about the ER experience for a POTSy called "What the hell is POTS?":
Until next time POTSy dudes and dudettes.