Hi new members, and welcome to the GERD forum.
Yes, Seven, the vagus nerve connects the heart with the esophagus, the stomach and the lower gut too. Sliding hernias aren't usually a problem, but if it's large or not actually a slider but paraesophageal (stays partly in chest all the time), you might need surgery to bring it down. I had that, not fun, but worth it. You could be getting referred pain in the back from the heart.
When I eat a food trigger I get rapid heartbeat (tachycardia), used to get reflux before the surgery. Need2b and Sever too, you might want to start a food journal to see if there are any specific foods or things you drink, or even medicines that trigger your heart and stomach discomfort. It takes a couple of months, but it's free. It would be good to see a GI doc and maybe get a barium swallow done to see if you have a hernia too.
You can look up my old posts on food logs/journals in the search box at the top of the page.
Just a thought.