Suggest Treatment For Palpitation With Hashimoto's Thyroiditis

I was recently diagnosed with Hashimoto's Thyroiditis. For the past 4 months though i have also had a chronic dry cough and the lymph nodes in my neck are enlarged. Over the past couple days i have had a constant "flutter" in my heart. At least once every 5 minutes it feels as though either my heart skips a beat or adds a beat. I am now 30 years old. Am in pretty good shape (i'm 5' 7" and 130lbs - have run 4 marathons...) When i was about 12 i was diagnosed with MVP, but my last echo was when i was probably 17 and they did not see the MVP as much and stopped yearly echo's. Other noteworthy hx is that in June 2008 i had a Right Temporal lobectomy with complete rescession of my right amydalia and hipocampus due to a cavernous hemangioma) - yeah...... i'm a bit of a mutant!