Palpitations, dizziness, Tachycardia heart racing when standing up

[WarpedTrekker]

I have not been diagnosed with Dysautonomia so far. Went to a Houston,TX doctor a few months ago, and those tests were normal. But I keep having issues like palpitations and rapid heart rate sometimes, when I sit down for extended periods, and then stand up.

Last night, I was on the couch watching TV. I started to get up, and immediately some major hard palpitations started and my heart rate shot up very fast. I have an AFIB condition that is controlled with medicine called Multaq. I thought maybe I was in AFIB so I took out my Kardia ECG device to record my heart rate. It was 145bpm+ . Then I started to get very anxious and shaky with trembling arms. and felt like I was going to pass out.  I waited a few minutes, and tried taking deep breaths. Eventually my heart rate went back down to normal 70-80bpm. 

My Electrophysiologist said the ECG showed I was in normal sinus rhythm and that I just had tachycardia. He has no explaination though, on why I get these episodes. I've had several of these now when I'm at home, and usually when I sit on my couch/recliner for an extended period. I've had a recent EKG and Echocardiogram which both were normal. I'm at a loss at what is causing these episodes. Sometimes I get just dizzy when standing up when getting out of my car.

I am contacting another Dysautonomia doctor to get tests ran again. 

My doctor thinks it is anxiety or panic attacks. I used to be on medicine for anxiety, but since I'm now on Multaq for AFIB, I'm unable to be on any SSRI medicine.

[StayAtHomeMom]

Definitely see another autonomic specialist but make sure you are properly hydrated. That is another one of those things that they blame my symptoms on besides anxiety. Have you checked your BP during these episodes?