I do phone consultations if she's interested. She's got way too complex a case for me to drop suggestions willy-nilly.
At least tell her that one of my first "suggestions" to anyone is to get the heck off of the Diet Pepsi.
Somewhere to begin your "hypothetical search" would be on this page
. The heart is electrical, and potassium and magnesium play huge roles in conducting the proper electrical currents through the cardiac muscle.
Even according to the USDA (hardly the authority on proper nutrition), over 75% of the US population is deficient in magnesium. It's a good place to start your "search".
Hope that gets you started.