What's the highest your heartrate has gotten? in Dysautonomia Discussion Posted Monday at 06:38 AM · Report reply My last day of work when I collapsed but remained awake. When I was at the hospital I was laying down and I think it was 156. Not sure what it would of been standing up. I was panicked as well though. My body was trying to faint for over an hour even while laying down. When they gave me Ativan my body stopped trying to faint. They kept me overnight because they had no idea why my heart was beating so fast. Basically they did an ultrasound and I wore a heart monitor all night and told me they have no clue and to see my primary care doctor and let me go the next day. I was terrified to be let out of the hospital. And that's where my journey began of finding out I had POTS. I saw a cardiologist and he didn't understand. He referred me to another heart doc who deals with electrical signals of the heart after I wore a heart monitor for a month with the cardiologist and saw my heart wasn't acting normal. The other heart doc immediately believed I had autonomic dysfunction and referred me to a autonomic dysfunction specialist. And there is where my POTS was confirmed.