no change in blood pressure

[jenwic]

I keep trying to figure out if I have POTS or IST. A few weeks ago I read posts by Carolyn and MomtoGiuliana that gave me some new info.

Carolyn said,"...some POTS people don't have any blood pressure issues at all. My understanding is the defining characteristic is elevated pulse upon standing or standing for a while (ortostatic tachycardia doesn't always go with orthostatic hypotension)."

Momtogiuliana said,"BP does not necessarily go down with POTS. POTS is defined by heartrate going up more than 30bpm on standing."

I have definite tachycardia with rising in the morning (130-135), after eating, with fever, with dental injections of certain types, with colds and viruses, etc. I have started checking my blood pressure when I have these episodes and it seems to remain about the same.

Can someone tell me where I can find research or information that says POTS doesn't necessarily relate to change in blood pressure?

Also, do any of you know any good dr.'s where I could be tested in southern Ohio?

Thanks!

[Sunfish]

i obviously can't speak to what your diagnosis truly is/should be, but in regard to the blood pressure question the info that others gave you was/is definitely accurate. POTS, by definition, does NOT necessatate any drop in blood pressure; some definitions in the literature actually state that if there is a significant drop in BP then POTS is not the most accurate diagnosis (though i have never heard of someone not being diagnosed b/c of too much of a BP drop...).

on the main dinet page, under the POTS Place section, it states:

"Postural orthostatic tachycardia syndrome is defined by excessive heart rate increments upon upright posture. A person with POTS will experience heart rates that increase 30 beats or more per minute upon standing and/or increase to 120 beats or more per minute upon standing (Grubb, 2000)."

you can read more at http://www.dinet.org/pots_an_overview.htm as well as find the references used.

Vanderbilt's page speaks not only to a rise in HR being the crux for diagnosis but specifically to the lack of a significant drop in BP. it reads:

"When orthostatic symptoms occur in patients, but blood pressure does not fall as much as 20/10 mmHg on assumption of upright posture, the patient has orthostatic intolerance (OI). Additional criteria used for the diagnosis of OI at Vanderbilt?s Autonomic Dysfunction Center include an increase in heart rate of at least 30 beats per minute with standing, and a standing plasma norepinephrine level of at least 600 pg/ml. Because upright heart rate is usually greatly increased, the term Postural Tachycardia Syndrome (POTS) is also used. "

the direct link is: http://www.mc.vanderbilt.edu/root/vumc.php?site=adc&doc=4788

the bottom line is that a drop in blood pressure is NOT a requirement for POTS/OI.

hope this helps,

melissa

[jenwic]

Thank you, Sunfish, for your reply. I had never seen the Vanderbilt site before. I really need to know what has been making me feel so bad for 13 years. Hopefully, soon I can find a good dr. and get an accurate diagnosis.

[ramakentesh]

Most definately - since the current belief is that the mechanisms that causes POTS dont necessitate a drop in blood pressure.

The Bake Institute in melburne Australia have demonstrated that in 14 POTS patients tested all patients had poor norepinephrine reuptake. This causes an excessive build up of norepinephrine in the body when under orthostatic stress (standing or excessive physical activity) which causes vasodilation so that the blood flows away from your head when standing excessively. There is a large and noticable reduction in blood flow to the brain which does not necesarily cause a reduction in blood pressure.