Atrial Fibrillation: Which Medications?

When people develop atrial fibrillation, the normal, healthy rhythm of the heart is disrupted with an irregular and rapid beating of its upper chambers.

Symptoms of atrial fibrillation (A-fib) include a rapid heart beat. There may be dizziness, confusion, palpitations, breathlessness, weakness, and chest pain. The person may have a heart murmur.

Triggers include caffeine, stress, and alcohol consumption. A person with hypertension, coronary artery disease, congenital heart disease, and other heart conditions is more likely to experience A-fib.

People who have a-fib have a greater risk of heart failure and five times the risk of stroke as people who don’t have this condition.

However, A-fib can be managed with with medications and lifestyle changes.

Read on to find out what medications are available for A-fib.

A-fib medications list

Medications for A-fib are defined by the specific health problems they address: preventing clots, controlling the heart rate, and managing the heart’s rhythm.

Preventing clots

Preventing clots is one of the main reasons people take A-fib medications. Drugs may be used to treat clots that are already present, or to thin the blood to keep clots from forming in the first place.

Two different kinds of medications are used:

  • antiplatelets, such as aspirin
  • anticoagulants, such as warfarin (Coumadin)

Other anticoagulant medications approved by the United States Food and Drug Administration (FDA) include:

  • dabigatran (Pradaxa)
  • rivaroxaban (Xarelto)
  • apixaban (Eliquis)
  • edoxaban

Controlling heart rate

Controlling the heart rate, often by slowing it down, can improve the quality of life of a person with A-fib. The American Heart Association report that the three main types of drugs used to control heart rate are:

  • beta-blockers, such as atenolol, bisoprolol, carvedilol, metoprolol, nadolol, propranolol, and timolol
  • calcium channel blockers, such as dilitiazem and verapamil
  • digitalis, or digoxin (Lanoxin), which regulates electrical currents in the heart

Managing the heart’s rhythm

Managing the heart’s rhythm is one of the more complex requirements of certain A-fib medications. Using medication to bring the heart back to a normal rhythm is also referred to as drug, or chemical cardioversion.

According to the American Heart Association, drug or chemical cardioversion can be achieved in two ways:

  • By limiting the ability of the heart to conduct electricity. This approach uses sodium blockers, such as flecainide or tambocor, propafenone or rythmol, and quinidine.
  • By interfering with the disruptive electrical signals that cause the heart to get out of rhythm. This uses potassium blockers, such as amiodarone, cordarone, pacerone, sotalol or betapace, and dofetilide.

Doctors are very cautious about prescribing these medications, also known as antiarrhythmic drugs. The reason is their side effects can cause serious problems with the heart rate and other essential bodily functions.

Which drugs are best for which people?

A-fib affects between 2.7 and 6.1 million people in the U.S. It is most common in those aged over 65, although it can affect younger people as well.

With so many people experiencing the condition, doctors look at a number of factors before they develop treatment plans, including:

  • an individual’s age
  • severity and frequency of symptoms
  • heart rate
  • stroke risk
  • pre-existing heart disease and other health conditions

Many doctors are now using the CHA2DS2-VASc scoring approach to assess a patient’s risk of stroke, and to determine which A-fib medications would best meet their needs.

To calculate an individual’s stroke risk, this approach awards points based on:

  • presence of congestive heart failure
  • presence of high blood pressure
  • if an individual is 65-74 of age
  • if a person is more than 74 years of age
  • presence of diabetes
  • previous strokes or blood clots
  • vascular disease
  • female sex

All these factors increase the risk of stroke and would encourage a doctor to recommend more aggressive treatment for a person with A-fib.

The main goal of A-fib medication is to reduce the risk of stroke, often with drugs like warfarin or other anticoagulants. These medications are generally combined with rate control medication to bring the heartbeat back to a more normal rate.

If anticoagulants and heart rate drugs are keeping patients symptom-free, and with a healthy heart rate, doctors may decide that no further medication is advisable, even if the patient is still in A-fib.

If a doctor thinks a patient should aim for a normal heart rhythm, or if initial treatment did not control their symptoms or heart rate, drugs are prescribed to better control the heart’s rhythm.

Specific side effects

Specific side effects of some A-fib medications include:

  • Amiodarone (Cordarone), one of the more effective antiarrhythmic medications, can be harmful to the lungs and, patients say, cause the skin to turn blue.
  • Aspirin, used to thin blood, can cause internal bleeding.
  • Dilitiazem (Cardizam or Taztia) may cause fatigue, as well as constipation or diarrhea.
  • Warfarin (Coumadin), an anticoagulant, can cause bleeding. People using it need to get regular blood tests to make sure their dosage is right.

Warfarin interacts with some foods, such as spinach and kale, as well as vitamins and other medications. Individuals using Warfarin need to ask their doctors what things to watch out for.

The drug also increases the risk of bone fractures, especially in older adults. Finally, studies indicate that genetics may keep as many as 25 percent of patients from responding well to this medication.