I have had Graves disease with symptoms on and off for around 9 years now. We thought I had successfully treated it with medication (twice) but alas it flared up again around the same time as my bc diagnosis...I just assumed I was stressed from surgery etc but a lot was the symptoms of hyperthyroidism (plus I was stressed too!!). Anyway I am back on medication and will probably have to look at a permanent solution eventually but my endocrinologist is in no hurry. He thinks my body has been through enough and since medication is working we are still going with that at the moment.
Graves disease can't be absolutely diagnosed by blood test alone so the scan is confirming the diagnosis and excluding anything else. (There is a condition called multinodular goitre and it doesn't resolve with medication and of course the dreaded C word but less likely given blood results etc. Also hashimotos hypothyroidism can initially present with high levels of thyroid then ut swaps to hardly any) The ecg is to ensure the high thyroid levels aren't causing abnormal beats....which it can. Uncontrolled Graves is life threatening (abd also makes you feel nervous, exhausted and jittery) so it's important to follow the plan set out. X