I am one of those who connected my tachycardia with my esophagus and stomach. When I ate certain foods I would first get reflux, then often this was followed by a bout of tachycardia. If I was able to get up a burp it would often stop. Often my tachycardia was accompanied by irregular heartbeats - according to my little BP machine.
With the help of my allergist I learned to keep a food log which helped me find a list of foods that triggered the reflux/tachycardia events. She had me do challenge testing on the individual components of the meals and foods and I came up with a fairly long list of ingredients. After googling the foods with the words "food allergies" I found out that all my foods contained sulfites. Other people have found different connections from this type of research.
Stopping the tachycardia events after they get started is often easy. The burping I was doing is similar to "valsalva maneuver" which consists of holding breath and bearing down as in having a bowel movement. Coughing often works too. My PCP has me chewing up an aspirin and a beta blocker. My cardiologist has me using atenolol as a beta blocker as it works quickly. Quite recently I had an event that I could not get stopped using all my tricks and after 4 hours I went to the hospital where they gave me a shot that reset my heart. I should have gone much sooner!
There have been some scientific papers written on several aspects of this condition. It's called cardio-esophageal reflex (not feflux!) or linked angina.
I think the entire GI system could possibly be involvedwith triggering the heart. The event that sent me to the hospital was preceeded by several hours of sudden onset diarrhea, then followed after several more hours by severe pain from diverticulitis with a nasty abscess, which sent me back to the hospital. I was admitted and treated with antibiotics, barely avoiding emergency surgery because I refused it. I had a short bout of tach while in the hospital, but was able to resolve it myself with the valsalva.
What started me on my research was having one of my episodes trigger a heart attack. I knew I had high cholesterol for many years, so my arteries were not in the best shape. One morning I ate some cold cereal with lovely dried fruit. I had a bout of diarrhea, didn't think much of it. I went out and was weeding the gardens when I got some reflux, felt like a gas bubble. Then I got tach which suddenly turned into typical heart attack symptoms. I knew what it was, went inside chewed up an aspirin and dialed 911. I had enough time to change out of my gardening clothes and wash up a bit. Still waiting I dialed everyone I could think of and found no one answering. Eventually a local police officer showed up, but there wasn't really anything he could do. After nearly half an hour I finally got transport, an IV and after another 20 minutes finally ended up in the ER. I was life flighted to a larger hospital and given a stent to open up the artery. Point of this part of the story is this condition is serious. Don't ignore your symptoms!
It's unlikely that your cardiologist or your GI doc have ever heard of this condition, so you have to document all your findings in a journal. Get a little portable BP machine. When your heart gets "irregular" write down the readings. It's not a full EKG machine, but should at least note "irregular heartbeats." Don't forget to write down times and what foods you ate!
So good luck and start keeping a food log to see if your symptoms have any connection to what you are eating. If you get a long episode of arrhythmia go to the nearest ER. Calling for an ambulance is safer than trying to drive yourself.