I have experienced most of my ectopic heartbeats, if not all, when I had a full or bloated stomach. The feeling that my stomach had something to do with this extra "hard" beats was always there. To explain this to my doctor always felt so stupid. The way I made sense of it was the following: Because I have an enlarged atrium I thought my heart was larger than normal and because of that, when my stomach was full, I could “feel” my heartbeats.
I have researched the Vagus nerv and found the following:
The vagus nerve is also called the wandering nerve, because it travels throughout the body. It actually extends from the brain to the stomach. It is also called the “mixed” nerve because signals are going in both ways. An irritated vagus nerve causes symptoms that vary widely, for me it was the Ectopic heartbeats.
Any comments about this vagus nerv and ectopic heartbeats would be very interesting and helpful.