Tachy at Night upon Standing

[woohoo7717]

Hi All,

I had a question. On my previous post I mentioned I got Tachy while lifting weights one time. I wanted to run something by you. Lately during the middle of the night, I have been waking up, and upon standing about 30 second post stand, my heart rate increases to say 120-135 level. The heartbeat is forceful, and the odd thing is it will fluctuate between fast, and then slow down a bit, then speed up, then slow down. This happens for about a minute and then it returns to normal.

Its odd because when I wake up in the morning I do not feel this, and if I nap it never happens. It only seems to happen at night between 11:30 and 1:00 am.

I had an event monitor and they only see normal sinus tachy and thought I was exercising but the rate fluctuates and it only happens about 20-30 seconds after standing.

Any ideas.

[kenkeith]

Dysautonomia (autonomic dysfunction) is a broad brush term that describes any disease or malfunction of the autonomic nervous system and that includes your tachy cardia as well as the standing episodes. This condition can cause periodic symptoms and dysautonomia can be caused by many different things; there is not one single, universal cause. The triggering mechanism can be elusive, if ever known, but there is treatment with medical therapy as well as diet, exercise, etc.  

You may want to research dysautonomia and see if that condition can be ruled out based on your symptoms and experience.  Thanks for you response, and keep us informed.

[ed34]

the anxiety will definitely add to it. As Kenkeith says, there is a lot of sudden adapting for the cardiovascular system to do, due to muscle demand and gravity for example. If I stand up from a chair, my pulse jumps from 68 to 90/100 but soon settles to around 75-80 again. If it didn't do this, I would have low oxygen going to the brain because gravity is pulling my blood down into the lower extremeties.

[woohoo7717]

Hi Ken,

I thought about POTS. This does not happen every night, nor does it happen every time, which everything I have read would happen to POTS sufferers. Typically the heart rate will not even be to fast, just way more forceful and faster but not SVT fast.

Typically it just feels like my heart is working harder for a minute going up and down in rate, and then settles, when this happens. Its annoying, but I dont get dizzy or lightheaded, but I do get anxious.

I know this is probably a tough one to determine, I have thought is this all in my head, or is this actually something.

[kenkeith]

Upon standing upright results invokes the automatic nervous system in a series of reflexive bodily responses.  This is compensation results for the effect of gravity upon the distribution of blood. These conditions are a result of an inappropriate response to this change in body position.

For an insight the response is to stabilize the standing position at normally takes about a minute.  During this process, the normal change in heart rate would include an increase in heart rate of 10 to 15 beats per minute, and an increase in diastolic pressure of 10 mm Hg, with only a slight change in systolic pressure.

There are those that have orthostatic intolerance, and for them there is an excessive increase in heart rate upon standing, resulting in the cardiovascular system working harder to maintain blood pressure and blood flow to the brain.

It is difficult to determine the hemodynamics as it relates to you may be related to ANS and there are tests to determine orthostatic intolerance.  There could be an electrolytic imbalance, thyroid issue, etc.

Hope this helps, and if you have any follow-up questions you are welcome to respond.  Take care.