It may be time to go beyond the General Practice MD and go to an EP (electrophysiologist) who is concerned with the electrical signals that command the heart to pump. The occasional `skipped beat' is not life threatening but it sounds like your case is more severe.
Afib is when your heart beats rapidly and erratically.
Aflutter is when you heart beats fast but steady.
In either case the heart is not pumping efficiently and may not pump enough blood to the brain which can cause fainting or worse.
Yes, I am being treated by an EP to control afib.