Hello and thank you for using HCM. I carefully read your question and i understand your concern. Don t worry, its nothing serious. Someone might experience increased heart rates for different reasons. It might happen from simple emotional stress to pathologyes like anemia, hyperthyroidism. The fact that we have excluded ischemic heart disease with angiography it is a great thing. This gives us insurance, because all other thinks are much easy to resolve. As you are allsow experiencing cramps, i would recommend you to do a good blood analyses with electrolytes and your thyroid hormones to exclude hyperthyroidism and problems with parathyroid gland. If i was your treating doctor i will recommend a holter rhythm monitoring. This can give us a real view of your rhythm tendency, your mean daily frequencies and only then we can understand if this needs to be treated with medications. Mean while avoid caffeine products, alcohol because they rise you frequencies. I encourage you to begin exercise training, because it helps in lowering the frequencies. l Hope I was helpful. BEST REGARDS