I am a bit surprised as there is no family history of heart issues on my mothers or fathers side. I must have picked up the dodgy gene from the pond.
I suspect the legacy off too much exposure to the "Sauce Company"... stress is the scourge of modern society. Add that to a bit of OCD and the wish to "do it right" ..
Once you are released by the medics then think long and hard about learning to relax and be calm. Meditation, Yoga, red wine..... whatever works for you!