High heartbeat rate - the longest experienced so far

Finishing yard waste cleanup in the street after the pickup;
Swept the leaves in the backyard;
Tried to wash up in the bathroom when my heart rate jumped again; thinking it would gradually level off after a while, I stood in the bathroom and wait, minutes past but no sign of recovering, I had to sit on the toilet to rest as I felt weak and sweating. Anita came to help and added towel and cloth on me. As it wasn't going away as before, Anita called 911, 6 firefighters came to the bedroom to help, after some questions, I was put on monitor and injected with some kind of medication - to slow down my heart rate - I leaned later that the injection was to stop my heart for a few seconds (4 to be exact) and restart it, much like reseting a device when it became non-responding, my heart rate gradually slowed down from over 200 to about 85. The ambulance took me to Regional Medical Hospital for observation; changing into hospital gown and lay in bed for the doctor. The doctor saw me briefly (not in grave danger) and said he will return after my blood test, the nurse drew 4 tubes of blood from me at 12:00 and the doctor returned to let me know that test results are ok and can go home, the nurse came a little later to give me the prescription and some info relating to the medication and my condition - I have the "Paroxysmal Atrial Tachycardia/Paroxysmal Supraventricular Tachycardia", also means "sudden onset of fast heart beating". The prescription was to prevent this from reoccurring but it does carry a number of side effects - see Wikipedia for more info. I need to check another possibility - overactive thyroid, common symptoms are excessive sweating, high heart rate (a form of Palpitation), diarrhea, weight loss, etc.

(IV on my right arm, blood was drew from the back of my left hand, a dozen vital sign monitoring stickers were placed on my chest and legs)

At the ER, an administrator (Sam) took my info and gave some valuable info when he found out I do not have insurance, Medi-Cal as well as other possible low income assists. A nice guy indeed.