What Is The Difference Between Oi And Pots?

[deucykub]

Hi, Sushi:

It sounds like you have (from a non-medical-professional opinion ) Orthostatic Intolerance (OI) in the form of Orthostatic Hypotension (OH) and/or Neurally Mediated Hypotension (NMH). OH is a rather speedy fall in blood pressure of 20 systolic or 10 diastolic (20/10). NMH tends to happen later after standing for a few minutes (about 12 for me, usually) that causes a dramatic fall in blood pressure and heart rate, resulting in pre-syncope (feeling of being very hot, nausea, tremor, blacking/greying out, visual disturbances, etc.) or syncope (flat out fainting).

OH can be a diagnosis in and of itself or can be a symptom of a diagnosis. For example, Pure Autonomic Failure (PAF) is an illness that includes the symptom of OH. In PAF the autonomic system does nothing to compensate for the fall in blood pressure. My understanding is the autonomic system reaction to orthostasis (upright posture) in OH and PAF are similar. The naturally compensating factor for OH includes the muscular-skeletal response (contracting of the legs muscles), but for some reason, the autonomic system does not attempt to or succeed in its attempt to compensate. Medications are usually administered to try to assist the compensating mechanisms by increasing blood volume or blood pressure. This like has a good description: Orthostatic Hypotension.

POTS is considered a partial dysautonomia - the heart is beating really fast to compensate for something, but it's debatable whether it is for bp or something else.

Orthostatic Intolerance means that you develop symptoms on going from lying down/sitting to standing up. It's an umbrella term for many different types of illnesses. Dysautonomias fall under that umbrella, and then under Dysautonomias you get into specific dx such as POTS, OH, PAF, MSA (multiple system atrophy) and the like.

I hope I got this right and that it clears up some of the confusion! I'm still in the learning curve, too, so I apologize for any errors!

Deucykub

[Tessa]

According to Dr. Rowe:

Postural tachycardia syndrome refers to an exaggerated increase in heart rate with standing. A healthy individual usually has a slight increase in heart rate?by about 10-15 beats per minute--within the first 10 minutes of standing. POTS is considered present if the heart rate increases by 30 beats per minute, or if it reaches 120 beats per minute or higher over the first 10 minutes of standing. POTS is an abnormality in the regulation of heart rate; the heart itself is usually normal. Some patients with POTS in the first 10 minutes of upright standing or tilt testing will go on to develop NMH if the test is continued; the two conditions often are found together, and they are not mutually exclusive diagnoses.

Neurally mediated hypotension refers to a drop in blood pressure that occurs after being upright. We define NMH by a drop in systolic BP of 25 mm Hg (compared to the BP measured when the person is lying flat) during standing or upright tilt table testing. Although NMH may be slightly more common in people with a low resting blood pressure, most people who develop NMH during standing have a normal resting blood pressure. NMH is an abnormality in the regulation of blood pressure during upright posture. It occurs when too little blood circulates back to the heart when people are upright, and triggers an abnormal reflex interaction between the heart and the brain. NMH is sometimes known by the following names: the fainting reflex, delayed orthostatic hypotension, neurocardiogenic syncope, vasodepressor syncope, vaso-vagal syncope. Syncope is the medical term for fainting.

According to Dr. Grubb there are 2 kind of POTS:

Partial Disautonomy: with a high hr when standing, that can reach 160 bpm or higher and other symptoms (we all know). During the TTT, >30 bpm during the first 1o minutes of tilt or >120 bpm during the same time, sometimes with a slight decrease of Bp.

Central Disautonomy (or B-Hypersensitivity): even though hr when tilted up is right, the brain is unable to know when to stop and the hr goes on increasing. Some of the patients with this kind of POTS have an high or low bp and a postural tachicardia.

These patients sometimes show an excessive reaction to isoproterenol (>30 bpm)...

I agree, it is confusing. I have heard that treatments are very similar. I wonder, does it really matter to know the kind of POTS one has if treatments are so similar?

Love,

Tessa

[Sushi]

Deucykub,

Thanks for the information and the link. From what you said and reading the link, it sounds like it is the neurally mediated type of hypotension. This fits with my experience of finding that benzodiazapams help me with stamina and chest pain, (currently taking low-dose klonopin) as I've read that they are only helpful if the problem is neurally mediated. I also find that the speedy fall in BP usually comes after I've been standing for a few minutes and I've always had enough warning time to sit down. Symptoms have varied a great deal over the years--pretty functional periods and sometimes pretty non-functional--but I've only found a knowledgeable doctor whose known how to treat it in the last year.

I've tried and not been able to tolerate florinof, midodrine, and clonodine, but the combo I'm taking now is working pretty well--I'm so grateful. Particularly the stattera and cymbalta stabilize my BP.

Thanks again.