If you're thinking about your heart every single day then please think good thoughts and be grateful to it for doing its job!!
Say simple and true things to yourself like:
"I am not a cardiologist."
"I am not a trained physician."
"How can I think I know more than a professional."
"I may be afraid but that doesn't make me an expert."
"My fear is what I know, not the objective fact of diagnosis."
It took me years, but repeating these over and over helped me to turn the professional diagnosing back over to the doctors. What arrogance on my part to think that without a single science class I know more than someone who has completed medical school and has been practicing cardiology for 20 years. Really.
I know that I am feeling funny symptoms. And I know my pain is real. But I do NOT know what is causing it, and to pretend that my thoughts are RATIONAL is pretty darn naive!!
This is the kind of thinking that got me back on the track of normal living, and where I began learning how to react to things without Panic and Anxiety.