Don ... I know I don't have to say this, but make sure you take care of yourself ...
BTW ... several years ago I was getting attacks of chest pain which would result in EMS calls to my house, frequent visits to the ER, etc. ... after several different cardio tests, it was determined (fortunately) that it was not my heart ... more 'attacks' (and they always had all of the 'heart attack' symptoms), more ER visits, many more tests, and finally it was diagnosed as pretty severe GERD ... after many trials of different meds, I am now on a daily dose of 'Dexilant' which has REALLY curbed those attacks ... so, do all the cardio testing, but don't overlook the possibility of GERD ...

Praying for your good health, and the good health of everyone here ...