Heart Disease and Heart Attack Question

My 16 year old son had Kawasaki disease at 4yr old he has been monitored since for any heart problems and up until last spring he has seemed ok. When we went to the dr last yr he was really tired lots of dizzy spells, fainted and chest pain. A EKG showed he had a junctional ryhthm and halter monitor showed his beats went down to 32 . We went to the cardiologist and he did an echo which was fine he suggested that the EKG was a faulty machine. Now a yr later symptoms are worse he actually passed out off the bench during a hockey game. He is very athletic playing rep hockey and lacrosse. In November he spent 9 days in a hospital with a bilateral peritonsillar abbcess after 2 surgerys to fix that he is scheduled to have his tonsils out on march 5. When we went for his pre op the EKG showed " a heart block" and his rate was 45bpm. We see the cardiologist this Friday and if he tells me again not to worry I think I might lose it. He is 16 tomorrow and I feel he should be able to walk up a fli