correction "blood flow into live" = "into LIVER" silly me :(
There is a very strong link between the digestive system and the heart. In fact many organs and the heart. The vegas nerve for example relates the condition of many systems back to the central nervous system. It affects the amount of stomach acid produced, the amount of blood flow into the live and also has the ability to slow down the heart rate. It is also believed by some experts that excessive gas build up in the stomach can put pressure on the nerve causing palpitations and other side effects.
There really isn't any correlation between the two. But your stomach can make you feel like your heart is acting up, or your heart will be acting up, and you may think it's just your stomach. So, any irregular, or rapid heartbeats needs further investigation.