No, POTS usually will manifest with increasing heart beats when you stand. If you get this while lying in bed or on a chair, then the condition is probably called a reversible heart block
, it is quite dangerous but fully reversible with treatment in almost all cases. Take a look here:www.ncbi.nlm.nih.gov/pubmed/2644885
"AV block associated with Lyme carditis is due to effects of the host inflammatory response directed at the spirochetes in cardiac tissue". It produces cardiac nerves conduction abnormalities:cid.oxfordjournals.org/content/early/2014/07/01/cid.ciu411.long
Because of this I was close to a heart attack a few times, before knowing i have Lyme and receiving treatment. You need to be very careful with your heart when you get to these very high bpm you can crash, so if left untreated and in some serious cases it can be fatal. But as the research papers say, it will go away with proper treatment.
Make sure to do an EKG and Echocardigram just to exclude some physical heart damage (muscle, valves,etc). And do a test of your electrolytes in the blood. If they cannot find anything and the doctors are clueless about
the causes of your tachycardia/arrhythmia, then it's because of this heart block.
I suggest you take it easy, take your Lyme treatment and make sure you add CoQ10 (at least 100mg/day) and Chelated Magnesium, these will help your heart muscle do its job better.