Treating the Likely Causes
Treatment depends on the cause.
If the cause is coronary artery disease, treatment may consist of:
Blood pressure medications
Coronary artery bypass surgery
Atrial fibrillation caused by an excess of thyroid hormones can be treated with medication or surgery. When rheumatic heart disease is the cause, the condition may be treated with surgery to replace heart valves damaged by the disease.
Treatment of the First Attack
When a person develops atrial fibrillation for the first time (or the first few times), doctors often try to restore a normal heart rhythm. This is particularly true if a person is having bothersome symptoms (like shortness of breath or weakness) from atrial fibrillation. Even if the person is not having symptoms, there is a reason to try to restore a normal rhythm: the longer the heart is left to remain in atrial fibrillation, the harder it is to restore a normal heart rhythm.
Several different medicines are used to restore a normal heart rhythm. Another treatment option is electrical cardioversion: a small shock is delivered to the chest, and the electricity can "re-set" the heart to a normal rhythm. This procedure works in most cases. But more than half of patients eventually develop atrial fibrillation again.
Another treatment to try to keep the heart from repeatedly going back into atrial fibrillation is radiofrequency catheter ablation. This procedure is typically performed in a catheterization laboratory of a hospital. The procedure uses radio waves to destroy tissue in the heart that is triggering the abnormal electrical rhythms that cause atrial fibrillation. If it is effective in eliminating recurrent attacks of atrial fibrillation, then it also eliminates the symptoms caused by atrial fibrillation as well as the risk of blood clots and the risks of the blood thinners needed to prevent blood clots.
Unfortunately, radiofrequency catheter ablation is not always effective, and also can produce serious adverse effects. So you need to talk to the doctor about the balance of benefits and risks.
Another surgical procedure involves creating scars in the atria. This hinders abnormal electrical activity from spreading and causing atrial fibrillation.
Keeping A Normal Heart Rhythm
When a normal heart rhythm has been restored, several different medicines may be given to try to hold the heart in a normal rhythm. This is called "rhythm control".
Sometimes, high doses of beta-blocker drugs can hold the heart in a normal rhythm. These drugs have relatively few serious adverse effects. For most patients, however, the most potent drugs for keeping the heart out of atrial fibrillation are the antiarrhythmic drugs, such as amiodarone, flecainide, dofetilide, propafenone, and sotalol. Although these drugs are more potent, they also can have serious side effects.
Slowing the Heart Rate
Sometimes—usually after the heart has slipped back into atrial fibrillation several times, despite treatment—doctors decide it is better to leave the heart in atrial fibrillation. When that happens, the heart rate usually needs to be slowed down to help the heart work most efficiently. This is called "rate control".
Medicines used to slow the heart rate include beta blockers, calcium-channel blockers, and digoxin.
Rhythm Control Versus Rate Control
For the average person with atrial fibrillation, large studies have found that rhythm control and rate control have approximately the same long-term consequences: one is not superior to the other.
For anyone who has chronic atrial fibrillation, or who may be going in and out of atrial fibrillation without knowing it (because it doesn't cause them symptoms, the risk of blood clots needs to be reduced. This requires "blood thinning" drugs.
The drug used most often is warfarin. This drug has been used in millions of patients over more than 70 years. Doctors have lots of experience in using it, and lots of knowledge about its possible side effects. Like any blood thinning drug, it has risks: a drug that reduces the risk of blood clotting thereby increases the risk of bleeding. Warfarin also needs to be monitored regularly: you need periodic blood tests to make sure the dose of warfarin has thinned the blood just enough and not too much.
There are several newer drugs that have become available or may soon be available, that do not require the periodic monitoring of warfarin, and that may have a lower risk of bleeding. They are considerably more expensive, and because they are new there is less known about their possible side effects than warfarin.
For some people, the best blood thinning drug is aspirin.