Ah, Luke... The issue isn't your heart, my dear.
This issue is that after a series of extensive a tests which all came back clear, you continue to think that something has been missed.
Bob said to you:
"You need to trust your test results."
To which you immediately respond with: "if something was wrong they would have picked it up, right?"
This above is your entire issue... Read it and see...your problem is sat in the above paragraph as clear as day:
*Doubt
*Reassurance
*Doubt.
That is the cycle and I say this to all, severe anxiety sufferers on this forum: When people say to you that, yes - there is a problem. But it is not with your heart (or whatever your health concern is,) what they are describing is the above.
I have no doubt that you will read this and most likely ask me whether or not I think your tests were accurate - because this is your fixation and all you can see.
Until you accept that your behaviour continues to generate your doubt and fears, you will continue to doubt every test and continue to believe you have an illness.
health anxiety is a form of OCD. obsessively and compulsively fixating upon an illness: fixating on symptoms, constantly checking for lumps, bumps or any other changes in your body is no different to checking light switches, doors and ovens 100 times a day.
Believing that you have an illness but are the only person in the world who does is no different to believing that you can change the outcome of things by repeating a movement, having items placed in certain order or clapping your hands a certain amount of times.
If left, it will begin to govern your every waking minute. OCD consumes.
CBT, therapy (or both,) is what you need to be pursuing. Not doctors. you need help to beat this...tests are not cutting it. If they did - you would be okay now.
So... You old methods aren't working for you - try a NEW one.