Rhythm Control Medication for Atrial Fibrillation
Your doctor will generally choose medication as your first course of action in managing your atrial fibrillation, often with rate control medication to slow the heart rate. If rate control doesn't work, then a rhythm control medication may be used to try to restore your heart's normal sinus rhythm. Rhythm control medication is also called "drug cardioversion".
Rhythm control drugs are risky due to serious side effects and the necessity for constant heart monitoring. It can take a year or more to get a continuous normal sinus rhythm. They are typically successful in about 60% of cases.
Types of Rhythm Control Drugs
Your doctor will decide which rhythm control drug is best for you based on the type of atrial fibrillation you have and your medical history, including the presence or absence of other existing heart disease. Here are the types of drugs used for rhythm control: 1
- Sodium channel blockers, which improve the heart's rhythm by slowing the heart's electrical conduction. Examples include Flecainide (Tambocor®), Propafenone (Rythmol®), and Quinidine (Various).
- Potassium channel blockers, which relax the heart muscle and slow the electrical signals that cause afib. Examples include Amiodarone (Cordarone®, Pacerone®) and Sotalol (Betapace®).
These medications are not considered to be highly effective and many have major side effects. For example, quinidine is only about 50 percent effective in maintaining a normal sinus rhythm over the long term, and flecainide, propafenone and sotalol are not much better. 2
Amiodarone is considered superior to these other medications in attaining and maintaining normal sinus rhythm, but may be the medication of last resort due to its lung toxicity and potential for long-term adverse effects. 3 One patient who took amiodarone mentioned that it can make you to turn blue like a "Smurf." Now that's an undesirable attribute for a medication!
Patients that were on rhythm control drugs said that those medications just left them feeling badly and persistently tired. For most, these medications worked at first, and in some cases controlled their afib for years, but eventually just stopped working.
While on rhythm control medication, anticoagulation is important as well. Conventional wisdom among doctors has been that if a patient was in normal sinus rhythm, the risk of stroke was decreased so significantly that anticoagulation was unnecessary. But recent studies have discovered that patients who stopped taking anticoagulants once their normal sinus rhythm was restored were actually at greater risk of stroke. 4
When medication proves unsuccessful, the American Heart Association suggests that catheter ablation or surgical ablation be considered. 2 For more information about these procedures, see Can Afib Be Cured?
1 "Antiarrhythmic Drugs" <http://www.americanheart.org/presenter.jhtml?identifier=153>, American Heart Association, [Internet], Copyright, 2006.
2 "Treating Atrial Rhythm Disturbances" <http://www.americanheart.org/presenter.jhtml?identifier=65>, American Heart Association, [Internet], Copyright, 2006.
3 Russo, Andrea M., MD, "Overview of the Contemporary Evaluation and Management of Patients with Atrial Fibrillation: What Every General Practitioner Should Know" <http://www.americanheart.org/downloadable/heart/1075_russo.pdf>, American Heart Association [Internet], Copyright, 2006.
4 Wyse, D. George, M.D., "Rate Versus Rhythm Control in the Management of Atrial Fibrillation" <http://www.americanheart.org/presenter.jhtml?identifier=3005618>, American Heart Association [Internet], Copyright, 2006.
