This is not going to be corrected over night. The racing heart IS from toxins and lack of oxygen as a result. It is also from magnesium deficiency. You must drink lots of pure water with added Sea Salt and take as much magnesium as your body can stand without giving yourself diarrhea. Anywhere form 400-800 milligrams. It will take time. your body will only absorb as much as it is able and that might not be much given your condition. I was there, it took many months of eating healthy , drinking lots of water , strict diet, bowel cleansing and avoiding stress as much as possible. Don't expect immediate results, it will take time to build up magnesium. You should also be eating lots of raw greens, drinking wheat grass juice and anything else that has lots of magnesium. There is also a company that makes liquid magnesium you can add to bath water or spray on yourself for absorbtion thru skin. However, I do not recommend you taking hot baths with the heart racing, being overheated will make your siutation worse until you get it under control.