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Autonomic Dysfunction FAQ

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1. What is the autonomic nervous system?
The autonomic nervous system (ANS) is the regulatory part of the central nervous system (CNS).  The ANS regulates the automatic functions within the body that occur without concious effort.  For example: heart rate, blood pressure, body temperature, respiration, digestion, etc.

2. What is autonomic dysfunction?
Autonomic dysfunction, (also called dysautonomia), is a chronic illness that causes a dysregulation of ANS functions.  It can be a symptom of another illness, or an illness in itself.

3. What are some examples of specific dysautonomias?

Two of the most commonly occurring forms of Dysautonomia are Postural Orthostatic Tachycardia Syndrome (POTS), and Neurally Mediated Hypotention (NMH).  Infrequent episodes of Vasovagal Syncope are also common in adolescents.  These patients may later outgrow the condition, or develop Neurally Mediated Syncope.  A couple of other examples of Dysautonomia include:

• Postural Orthostatic Tachycardia Syndrome (POTS)
  • Hyperadrenergic POTS (H-POTS)
  • High-Flow POTS
  • Normal-Flow POTS
  • Low-Flow POTS
• Neurally Mediated Hypotension
• Vasovagal Syncope/Vasodepressor Syncope
• Hyperadrenergic Sensitivity
  
• Neurally Mediated Syncope/Neurocardiogenic Syncope (NMS/NCS)
• Orthostatic Hypotension/Orthostatic Intolerance
• Hereditary Sensory and Autonomic Neuropathy (HSAN)
  • Familial Dysautonomia/Riley-Day Syndrome (FD)
• Central Nervous System Dysautonomia
  • Generalized Dysautonomia
  • Multiple System Atrophy/Shy-Drager Syndrome (MSA)
  • Pure Autonomic Failure/Bradbury-Eggleston Syndrome (PAF)
• Mitochondrial Encephalomyopathies with Dysautonomia
• Parkinson's Disease with Autonomic Failure
• Congenital Central Hypoventilation Syndrome (CCHS)
• Autoimmune Pan-Dysautonomias
• Autonomic Neuropathies
  • Autoimmune Autonomic Neuropathies
  • Idiopathic Autonomic Neuropathies
• Mitral Valve Prolapse with Dysautonomia (MVP)
  
• Inappropriate Sinus Tachycardia with Dysautonnomia (IST)
• Chronic Fatigue Syndrome with POTS/NMH (CFS)

4. What is a Vasovagal Reflex?
In order for you to stay concious, the ANS must keep the heart pumping oxygenated blood to your brain.  A Vasovagal Reflex is the result of an exagerated responce by the ANS.  This can result in nausea, or fainting.  Fainting is not all that uncommon, and Vasovagal Reflex Syncope is the most common cause.  Some individuals may only faint once in their lifetime, but others have repeated symptoms.  Those with repeated symptoms are often diagnosed as having dysautonomia.

5. What are some of the more common symptoms of an autonomic dysfunction?
Some of the more common symptoms include: orthostatic intolerance, tachycardia, bradycardia, low blood pressure, high blood pressure, sudden drops in blood pressure, extreme fatigue, syncope, pre-syncope, nausea, episodic vomiting, tremulousness, polydipsia, frequent urination, frequent headaches, weakness, lightheadedness, unsteadiness, heat intolerance, flushing, cognative dysfunction, delayed gastric emptying, constipation, sleep-related problems, anxiety/panic symptoms, visual disturbances, disorientation, etc.  Not every form of dysautonomia causes every symptom, nor does every patient experience the same group of symptoms.  Some patients experience many, while others experience very few.

Additional Information

Postural Orthostatic Tachycardia Syndrome:
- http://www.dinet.org/pots_an_overview.htm
- http://www.mc.vanderbilt.edu/root/vumc.php?site=adc&doc=4788
- http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1501099&tool=pmcentrez
 
Neurocardiogenic Syncope/Neurally Mediated Syncope:
- http://www.dinet.org/NCS/ncs.htm
- http://www.mc.vanderbilt.edu/root/vumc.php?site=adc&doc=4789
- http://pediatrics.med.nyu.edu/dysautonomia/autonomic-disorders/neurally-mediated-syncope
- http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=101078

Pure Autonomic Failure:
- http://www.dinet.org/PAF/paf.htm
- http://www.mc.vanderbilt.edu/root/vumc.php?site=adc&doc=4790
- http://pediatrics.med.nyu.edu/dysautonomia/autonomic-disorders/pure-autonomic-failure

Multiple System Atrophy/Shy-Drager Syndrome:
- http://www.dinet.org/MSA/msa.htm
- http://www.mc.vanderbilt.edu/root/vumc.php?site=adc&doc=4791
- http://pediatrics.med.nyu.edu/dysautonomia/autonomic-disorders/multiple-system-atrophy

Familial Dysautonomia/Riley-Day Syndrome/HSAN-3:
- http://pediatrics.med.nyu.edu/dysautonomia/autonomic-disorders/familial-dysautonomia
- http://pediatrics.med.nyu.edu/dysautonomia/autonomic-disorders/hsan

Dopamine-Beta-Hydroxylase Deficiency:
- http://www.mc.vanderbilt.edu/root/vumc.php?site=adc&doc=4792

Mitral Valve Prolapse Dysautonomia:
- http://www.mvprolapse.com/dysautonomia.html

Autonomic Neuropathies

- http://emedicine.medscape.com/article/1173756-overview

- http://pediatrics.med.nyu.edu/dysautonomia/autonomic-disorders/autonomic-neuropathy