Atrial Fibrillation – rhythm control, but how?

So maybe we’ve done rate control and you’re still not ok.  Or perhaps the atrial fibrillation is at the stage where it comes and goes.  Maybe we should try to get and keep you in a normal rhythm.

There are a few strategies to do this.

The simplest is a DC cardioversion.  This uses an electric shock across the heart to reset the atrial rhythm.  The good news is that this is quick, almost always works initially.  The bad news is that if you’ve had atrial fibrillation for more than a day, you should be on anticoagulants to prevent blood clots from forming in the atrium.  It’s also quite painful so needs to be done under deep sedation or a general anaesthetic.

The other bad news is that the atrial fibrillation can start again.  Sometimes it can recur quite quickly.  Medications can be used to try to keep you in a normal rhythm.  In the UK, the commonly used ones are amiodarone, flecainide, sotalol and possibly dronedarone. These can successfully control the rhythm but are not perfect, but are certainly worth trying.

There is another strategy which is a procedure called ablation.  Current guidelines suggest that ablation be offered if drug therapy doesn’t work, but more data is being published to say that it is a reasonable first line option in atrial fibrillation that comes and goes (paroxysmal).

Ablation refers to a procedure where we selectively treat part of the heart muscle to prevent rhythm disturbances.  For atrial fibrillation, it seems that the trigger for atrial fibrillation is electrical activity coming from muscle sleeves around the veins from the lungs as they empty into the left atrium.  So in ablation, we either freeze or microwave tissue around the veins to electrically isolate the veins from the atrium.  The medium term success rates for ablation in patients with paroxysmal atrial fibrillation is above 70%, though some patients will need more than one procedure.  For persistent atrial fibrillation (ie the heart is in atrial fibrillation for more than a week, or needed drugs or cardioversion to restore normal rhythm), the medium term success rates are more like 50%.  It’s important to know that lifestyle measures such as weight loss do significantly improve the success rates so this is extremely important.

Bad news about ablation – like any procedure there are risks associated with it such as groin damage, bleeding around the heart, damage to the nerve to the diaphragm resulting in breathlessness and very rarely heart attack, stroke or damage to the gullet which can be fatal.

It’s worth speaking to a specialist to discuss the best strategy for you as it can be quite a complex decision.

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