Amiodarone Damages Thyroid—A-Fib Free After 2 Ablations by Dr. Marc Dubuc, Montreal Heart Institute
By Louis Therrien, Montreal, Canada, June 2014
“Silent” A-Fib Discovered
My A-Fib was diagnosed during an annual checkup with my GP in 2008. When going through the ECG, they found that my heart was going over 200 BPM. So I was sent to the ER and then the hospital for eight days where they tried medication and a cardioversion to convert me back to a regular rhythm, without any success. I was sent back home with medication and finally converted back to regular rhythm after another week.
Amiodarone damages thyroid, NSR with Rythmol
One of the medications was Amiodarone, which after a few months caused a thyroid problem and put me back into A-Fib. At that point, I was referred to the Montreal Heart Institute (MHI) where I met Dr Marc Dubuc, a specialist in irregular heart rhythms. He immediately took me off the Amiodarone and put me on Rythmol. I went back into normal sinus rhythm.
ablation, then 3 years later cyroballoon ablation
The Rythmol worked well until 2010 when I developed a Flutter arrhythmia. I then went through my first ablation in the right atrium by Dr Dubuc of the MHI. This went well, and my A-Fib and Flutter did not reappear for several years. The summer of 2013, my A-Fib started up and became more and more constant (3 to 4 episodes of 1 to 2 hours a day). Dr Dubuc scheduled me for a CryoBalloon ablation of the left atrium which was done in October 2013.
Post ablation flutter & cardioversion
The operation went well, but the following day a Flutter appeared; so back to the hospital after a few days at home to see if it would resolve by itself. Since the Flutter was still present after a few days, Dr Dubuc debated between going back for a touch up procedure. But after discussing with the team at the MHI, he decided that this Flutter was probably caused by the A-Fib operation and originated in the left side of the heart versus a true flutter coming from the right side. The decision was to give me a cardioversion to bring the heart back to sinus rhythm, and this procedure was a success.
I am happy to report that after 7 months, I have had no A-Fib episode. I have resumed exercising. And the only symptoms I get are the rare extra-systoles [premature beats] which seem to occur less and less often as time goes by. All in all, I was not sure about the operation. And when faced with it, Dr Dubuc did not leave me a chance to decide. But I must say that I have no regrets and should have done the ablation earlier. The operation was a breeze. And the team along with Dr Marc Dubuc at the Montreal Heart Institute are excellent and very knowledgeable. MHI is, in my opinion, one of the top-notch institutions in the world.
Living with fear but the confidence is coming back
This has been quite an adventure of ups and downs in the last 6 years for someone my age (45 years old and a very active cyclist). Living with this fear of when and where the A-Fib will strike. Now that the procedure is done, the more time goes by, the more the confidence is coming back. I must admit that right after the operation, there is always the doubt of will I be in the percentage rate where the operation is not a success? And I am reminded of that every time someone asks me ”So, how are you after the operation? Was it a success?” and my answer is ”So far it is, but time will tell” as this is not the condition where you can be told you are cured, but you can only know until the next A-Fib episode, which in my case, I hope is never! I try the keep a positive attitude so that my body will follow.
Louis Therrien louis-therrien(a)hotmail.com Montreal, Canada
As Louis experienced, it’s unfortunately all too common for the drug amiodarone to cause thyroid and other serious side effects. Amiodarone is usually only given for short periods of time such as after an ablation and with careful monitoring for side effects.
It’s still a topic of debate among doctors whether to do a left atrium ablation if a patient only has right atrium flutter. Since doctors are in your heart already, many will do an A-Fib ablation in the left atrium as well as a right atrium A-Flutter ablation. A-Fib often coexists with A-Flutter or lurks behind it. In a small study people did much better if they had both an A-Fib and an A-Flutter ablation at the same time even though they only seemed to have A-Flutter.1
Louis’ case was more difficult than most in that he developed left atrium flutter after an A-Fib ablation. Usually Flutter comes from the right atrium and is easily fixed. Happily in Louis’ case an electrocardioversion shocked him out of the left atrium flutter. But he may eventually have to go back for a touch-up ablation if his left atrium flutter returns. However, this should be a much easier and quicker ablation than his original left atrium A-Fib ablation.
- Navarrete, A. et al. “Ablation of atrial fibrillation at the time of cavotricuspid isthmus ablation in patients with atrial flutter without documented atrial fibrillation derives a better long-term benefit.” Journal of Cardiovascular Electrophysiology, July 19, 2010. Navarrete A, Conte F, Moran M, Ali I, Milikan N. Ablation of atrial fibrillation at the time of cavotricuspid isthmus ablation in patients with atrial flutter without documented atrial fibrillation derives a better long-term benefit. J Cardiovasc Electrophysiol. 2011 Jan;22(1):34-8. doi: 10.1111/j.1540-8167.2010.01845.x. PubMed PMID: 20662976.↵