Three weeks ago, a blood test confirmed the Amiodarone has affected my thyroid and made it overactive. Amiodarone was stopped immediately and my ablation cancelled ( much to my great disappointment) until my thyroid is under control. I saw an endocrinologist last week who said my normal level T4 was 14.5 and is now 32.8 but after two weeks of stopping Amiodarone it had come down to 28, he has put me on carbimazole to bring thyroid down ( as it may need the extra help ) and changed my bisoprolol 1.25 mg once a day to propranolol 20 mg ( or 40mg if HR starts going up over 100 at rest ) 3 times a day for the next 6 weeks. Blood test next Thursday fingers crossed it's heading down further. I'll keep you posted .