Thank you for visiting Healthcaremagic.com.
In response to your question regarding your friend's mild chest pain
, I would initiate a cardiac workup initially. Primarily this would be the most life-threatening and debilitating illness and must be ruled out.
I would also check for an abdominal anurysm based on symptoms of feeling "his heart beat in his stomach". I cannot explain why his symptoms are alleviated by his actions. He may be lucky that his condition appears stable for a "couple of years". However, if this is cardiac in nature, he cannot expect this condition to continue - it could get worse unexpectedly.
Additionally, his symptoms could be benign and just represent a bad case of indigestion
In any case, it is wise to get this checked out.