sounds very simmilar to the symptoms I suffer from occasionally...... severe sudden onset, right epigastric pain, radiating to my right shoulderblade and into myneck and lower jaw.....make me roar sometimes it is so bad.I have had full investigations and now diagnosed with oesophageal spasm,symptoms can be very simmilar to heart attack !!! Not much can be done,I take nexium daily but one thing I have found effective is that on immediate onset of symtoms I start chewing ICE and swallowing it chunky,this helps keep it at bay,may take half and hour to subside but it works for me !