This Web page is designed for the general education of patients and their families.
Disclaimer: The answers provided are the opinion of Dr.
Tom Chelimsky. No patient should make any changes in their care without
first consulting their physician.
Question 1: I have postural orthostatic tachycardia. What other disorders can this be associated with? I am taking Flurinef, which helps with the lightheadness but I am still extememly fatiuged and brain fogged. Any suggestions?
Dr. Chelimsky: Postural orthostatic tachycardia syndrome (POTS) is quite common in and of itself. It usually occurs after a viral syndrome ("flu") but may occur without any heralding event, or may also be inherited (check to see if you have relatives with milder similar symptoms). If there is an autonomic laboratory near where you live, it is best if the diagnosis can be confirmed by this type of testing (usually a heart nerve check, and a sweat nerve check of some type), and damage to the nerves can be excluded.
This diagnosis is a SYNDROME, not a disease, and there are probably many types of diseases that lead to this set of symptoms. Depending on the reasons that the symptoms are there, the treatment would vary. If the veins are not returning blood to the heart, you need more salt loading (you should eat lots and lots of salt each day, aiming for 15 g per day). If the arteries are not constricting properly, a drug called midodrine may be helpful. Walking in the water and thigh strengthening exercises may be quite helpful in reconditioning you regardless of the cause of the problem.
If you are still fatigued and lightheaded, this means you need more support for your blood pressure. I would get a blood pressure cuff from the pharmacy, and record once a day standing and lying pressures (and pulses) to see where you stand. Then bring the record to your doctor and ask if any further help is needed.
The good news is, that usually the problem lasts 5-10 years and then goes away.
Question 2: In your reply to a question regarding syncope on your website, you make a few recommendations to help remedy the problem. I was wondering if you could give medical explanations for why some of these recommendations are valuable for patients with neurally mediated hypotension:
Dr. Chelimsky: The B complex and Vitamin E are particularly crucial for nerve growth and regrowth. I recommend them generally for anyone who has peripheral nerve damage of any cause (eg diabetes, cancer, Guillain-Barré,etc...), and therefore recommend them for people with orthostatic hypotension on the assumption that some of their problem may be due to degeneration of the nerves which control the blood vessels (autonomicnerves). This is not specific for syncope, but quite general for anyone with nerve damage.
Vitamin B6 has been shown to be toxic, especially to the sensory nerves, when taken in excess (usually > 300 mg/day). Therefore we recommend never to take this medication in high dose, but only at thestandard dose of 50 mg/day, at which level it is necessary and beneficial.
I do not know about other vitamins, but I know of no reports suggesting that they be avoided.
Question 3: Why does raising the head of your bed help your body retain water/fluid volume?
Dr. Chelimsky: When you lay flat for a period of time, there is less demand for fluid because it is all at the same gravitational level as the heart. The more upright you are, the more demand for fluid to keep enough blood in the system to feed the brain in spite of the strong gravitational pull into the legs. So when you lay down, blood comes rushing back to the heart, a little like the rapid tides at St Michel in France. As a result, a signal is sent to the kidneys to get rid of some of the "extra" fluid. The same thing happens to astronauts in space due to absence of gravity. If you put your head of the bed up, you markedly reduce this effect, by keeping some of the fluid in the legs. Note that pillows don't work, because the person's legs must be low. You have to use bricks under the legs of the bed.
Question 4: Why is exercising (especially heavy exercise) dangerous?
Dr. Chelimsky: When a person is already short of blood to the brain, anything that will divert the flow of blood further is potentially harmful, as it could produce fainting. When you exercise, muscles call for additional flow, and reduce what's available for the brain if the overall supply is limited (normally it is not, and can increase to meet the demand, but in orthostatic hypotension, blood pressure is unable to rise to allow for additional flow). I would not call this "dangerous", only risky, because a simple faint, as long as the person does not get harmed and can get into a flat position, is usually not a life-threatening event. The person can then adjust their exercise to a lower level and continue next time. In fact, I do strongly recommend a GRADUAL strengthening program for endurance as it will help the overall condition. The best one is water walking and water jogging, because the water acts as a stocking and pushes blood back to the heart during the exercise.
Question 5: If I suspect I have neurally mediated hypotension, what "type" of doctor should I see for a diagnosis. My primary care internal medicine physician didn't really seem to know what I was talking about when I mentioned it to him. Should I seek an endocrinologist, cardiologist, neurologist, or somebody else?
Dr. Chelimsky: Anyone of these would be fine, but they need to have a special interest in fainting and hypotension. People with this interest tend to be in one of the three specialties you mentioned. Call ahead to find out if this is a PARTICULAR interest of the physician (not just that they're willing to see you).
If you have a question, please submit it to Dr. Chelimsky.