The Skeptical Cardiologist is a firm believer in the benefit of maintaining normal rhythm in most patients who develop atrial fibrillation (AF, Afib, see ).
Sometimes this can be accomplished by lifestyle changes ( and , treating sleep apnea, etc.). But successful long term maintenance of normal sinus rhythm (NSR) more often requires a judicious combination of medications and electrical cardioversions (ECV).
It is also greatly facilitated by a compliant and knowledgeable patient who is regularly self-monitoring with a personal ECG device.
My article on electrical cardioversion (see ) was inspired by a patient we'll call Sandy who asked me in April 2016, "How many times can you shock the heart?"
In 2016, I performed her fifth cardioversion. Last week, I did her sixth.
Her story of AF is a common one that exemplifies how excellent medical management of AF can cure heart failure and mitral regurgitation and create decades of an AF-free, happy and healthy existence.
A Tale of Six Cardioversions
Sandy had her first episode of atrial fibrillation in 2001, underwent a cardioversion at that time, and then as far as she knew had no AF problems for 14 years. I've seen numerous cases like this where following a cardioversion, patients maintain NSR for a long time without medications, but I've also seen many in whom AF came back in days to months.
In 2015, she saw her primary care physician for routine follow-up and AF with a rapid rate was detected. She had been noticing shortness of breath on exertion and a cough at night but otherwise had no clue she was out of rhythm.
When I saw her in consultation, she was in heart failure and her echocardiogram demonstrated a left ventricular ejection fraction of 50% with severe mitral regurgitation. She quickly went back into AF after an electrical cardioversion (ECV) and reverted to AF again following a repeat ECV after 4 days on amiodarone (Nexterone).
Since amiodarone can take months to reach effective levels in the heart, we tried one more time to cardiovert after loading on higher-dose amiodarone for 1 month. This time she stayed in NSR.
Following that cardioversion she has done extremely well. Her shortness of breath resolved and follow-up echocardiograms have demonstrated resolution of her mitral regurgitation.
She had purchased a for personal monitoring of her rhythm, and we were able to monitor her rhythm using the . Recordings showed she was consistently maintaining NSR after her 2016 ECV.
I've written extensively on the great value of KardiaPro used in conjunction with the Kardia mobile ECG device for monitoring patients pre- and post-cardioversion for atrial fibrillation. Sandy does a great job of making frequent Kardia ECG recordings, almost on a daily basis, so even though she has no symptoms we are alerted to any AF within 24 hours of it happening.
Amiodarone: The Big Gun For Stopping AF
The recurrence of AF that Sandy had in 2016 occurred 8 months after I had lowered her amiodarone dosage to 100 mg daily.
Amiodarone is a unique drug in the AF toolkit. It is by far the most effective drug for maintaining sinus rhythm, an effect that makes it our most useful antiarrhythmic drug (AAD).
It is cheap and well-tolerated. Unlike other drugs that we use for controlling atrial fibrillation, it takes a long time to build up in heart tissue and a long time to wear off.
It is the safest antiarrhythmic drug from a cardiac standpoint. Unlike many of the other AADs, we don't have to worry about it bringing out more dangerous rhythms such as ventricular tachycardia or ventricular fibrillation.
Amiodarone, however, is not for all patients -- it has significant long-term side effects that necessitate constant vigilance by prescribing physicians, including thyroid, liver, and lung toxicity.
I monitor my patients on amiodarone with thyroid and liver blood tests every 4 months and a chest x-ray yearly. I try to utilize the minimal dosage that will keep them out of AF.
In Sandy's case, it was apparent that 100 mg was too little. With an increase back to 200 mg daily, the AF remained at bay.
In early 2017, Sandy read on Facebook that amiodarone was a "poison," and after discussing the risks and benefits we decided to lower the dosage to 200 mg alternating with 100 mg. It is common and appropriate for patients to be fearful of the potential long-term and serious consequences of medications. For any patient taking amiodarone, I always offer the option of stopping the drug with the understanding that there is a strong likelihood of recurrent AF within 3 months once the drug wears off.
In October 2018, with Sandy continuing to show normal heart function and maintain NSR as documented by her daily Kardia ECG tracings, we decided to further lower the dosage to 100 mg daily.
Six months later, she noted one day that her Kardia reading was showing a heart rate of 159 bpm and diagnosing atrial fibrillation. AF had recurred on the lower dosage of amiodarone. She had no symptoms, but based on prior experience we knew that soon she would go into heart failure.
Thus, her amiodarone was increased and a sixth cardioversion was performed. We could find no trigger for this episode (unless the Bloody Mary she consumed at a Mother's Day brunch two days prior was the culprit.)
Medical Management Versus Ablation
Many patients seek a "cure" for atrial fibrillation. They hear from friends and neighbors or the interweb about ablation or surgical procedures that promise this. , for example, promotes these types of procedures saying "Catheter ablation and surgical maze procedures cure atrial fibrillation ..."
In my experience, the majority of patients receiving ablation or surgical procedures (maze procedure and its variants) ultimately end up having recurrent episodes of atrial fibrillation. Guidelines do not suggest that anticoagulants can be stopped in such patients. Often, they end up on AADs.
I've prepared a whole post on ablation for AF, but the bottom line is that there is no evidence that ablation lowers the AF patient's risk of dying, stroke, or bleeding. My post will dig deeper into the risks and benefits of ablation.
There is no cure for AF -- surgical, catheter-based, or medical.
In the right hands, most patients can do very well with medical management combined with occasional cardioversion.
Who possesses the right hands? In my opinion, most AF patients are best served by a cardiologist who has a special interest in atrial fibrillation and takes the time to read extensively and keep up with the latest developments and guideline recommendations in the area. This does not need to be an electrophysiologist (EP doctor).
I have a ton of respect for the EP doctors I work with and send patients to. But I think that when it comes to doing invasive, risky procedures, the decision should be based on a referral/recommendation from a cardiologist who is not doing the procedure.
In many areas of cardiology, we are moving toward an interdisciplinary team of diagnosticians, interventionalists, surgeons, and non-cardiac specialists to make decisions on performance of high-risk and high-cost but high-benefit procedures like valve repair and replacement, closure of patent foramen ovale, and implantation of left atrial appendage closure devices.
It makes sense that decisions to perform high-risk, high-cost atrial fibrillation procedures also be determined by a multi-disciplinary team with members who don't do the procedure.
This is a rule of thumb that can also be applied to many surgical procedures as well. For example, the decision to proceed to carotid endarterectomy is typically made by the vascular surgeons who perform the procedure. In my opinion, this decision should be made by a neurologist with expertise in neurovascular disease combined with a good cardiologist who has kept up with the latest studies on the risks and benefits of carotid surgery and is fully briefed on the latest guideline recommendations.
, is a private practice noninvasive cardiologist and medical director of echocardiography at St. Luke's Hospital in St. Louis. He blogs on nutrition, cardiac testing, quackery, and other things worthy of skepticism at , where a version of this post first appeared.