I can never tell if you’re serious or not. But in case you are, I do EKGs on patients sometimes. It is not like an ultrasound. It’s not a type of imaging. It’s a measurement of electrical activity in the chambers of the heart. It shows if your heart rhythm is normal. A psychiatrist is not likely to be of much use with cardiac issues. He will tell you it is all in your head.
Screw what your doctor says and go get a second opinion. Individual doctors don't know everything... they're only human, just like the rest of us.
If it's a problem with your medication, then you really need to get that worked out. You should never just ignore problems caused by drugs. What if you ever need to go on a temporary medication, like an antibiotic or steroid for some sort of infection/inflamation from an injury? If you're not handling long-term medication well, what happens if you end up with some weird interaction from adding in another? Especially if it's messing with your heart and nervous system...
That sounds bloody scary. It sounds a little like some episodes my brother had and he found out <very unscientific explanation> there's a flap over one of the vessels in your heart, that as you get older is met to fuse closed but his never did.</> So it wasn't really serious as long as he kept an eye on his heart rate. Although his didn't happen regularly and obviously your heartbeat shouldn't be increasing so much while sleeping.