"Postural orthostatic tachycardia syndrome (POTS, also postural tachycardia syndrome) is a condition of dysautonomia, more specifically orthostatic intolerance, in which a change from the supine position to an upright position causes an abnormally large increase in heart rate, called tachycardia. Several studies show a decrease in cerebral blood flow with systolic and diastolic cerebral blood flow (CBF) velocity decreased 44% and 60%, respectively. Patients with POTS have problems maintaining homeostasis when changing position, i.e. moving from one chair to another or reaching above their heads. Many patients also experience symptoms when stationary or even while lying down."
"The causes of POTS are not fully known. Most patients develop symptoms in their teenage years during a period of rapid growth and see gradual improvement into their mid-twenties. Others develop POTS after a viral or bacterial infection such as mononucleosis or pneumonia. Some patients develop symptoms after experiencing some sort of trauma such as a car accident or injury. Women can also develop POTS during or after pregnancy. These patients generally have a poorer prognosis.
In one large test, 12.5% of 152 patients with POTS reported a family history of orthostatic intolerance, suggesting that there is a genetic inheritance associated with POTS.
So far no one has provided an explanation for POTS which is applicable to all sufferers, however there are many theories;
Alpha-receptor dysfunction may be occurring in some POTS patients. Alpha-1 receptors cause peripheral vasoconstriction when stimulated. Alpha-1 receptor supersensitivity may be causing dysautonomia in some patients.
Beta-receptor supersensitivity may occur with hyperadrenergic states in some people with POTS.
Hyperdopaminergic states may be the underlying problem for some people with orthostatic intolerance. Some patients have been found to have a significant increase in upright dopamine levels. Free plasma norepinephrine also tends to be higher in these patients.
Reduced venous return is one of the main mechanisms that causes POTS symptoms. Venous return can be reduced due to conditions such as low plasma volume (hypovolemia), venous pooling and denervation. A hyperadrenergic state may result as the body attempts to compensate for these abnormalities.
Sympathetic Overactivity is observed in many POTS patients. The sympathetic overactivity can be secondary to a number of factors, some of which may be peripheral denervation, venous pooling, or end-organ dysfunction. Sympathetic underactivity can also occur in some forms of orthostatic intolerance, such as pure autonomic failure. "
Symptoms just to name few:
* lightheadedness, sometimes called pre-syncope (pre-fainting) dizziness (but not vertigo, which is also called dizziness)
* exercise intolerance
* extreme fatigue
* syncope (fainting)
* Excessive thirst (polydipsia)
* cold extremities
* chest pain and discomfort
* muscle weakness
* visual disturbances
* brain fog
* decreased mental stamina
* difficulty finding the right word
* impaired concentration
* sleep disorders"
Ring any bells?
More about POTS in Wikipedia: http://en.wikipedia.org/wiki/Postural_o ... a_syndrome
There seems to be at least one person with POTS that has gone through angioplasty for her CCSVI. She is blogging about it in her blog http://bobisdysautonomia.blogspot.com/
Got to put her veins in here because pics dont lie