Atrial fibrillation: Which medications
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.
However, a person can manage A-fib 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.
Some medications for A-fib work to prevent blood clots by thinning the blood.
Preventing blood clots is one of the main reasons people take A-fib medications.
People might use drugs to treat clots that are already present or to thin the blood and keep clots from forming in the first place.
Two different kinds of medications are used:
- novel oral anticoagulants (NOACs)
- antiplatelets, such as aspirin
NOACs are the preferred route of drug treatment for preventing blood clots.
The Food and Drug Administration (FDA) has approved the following NOACs for use in treat:
- dabigatran (Pradaxa)
- rivaroxaban (Xarelto)
- apixaban (Eliquis)
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?
Doctors calculate the risk of stroke using a variety of factors, including blood pressure.
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.
When to use them?
Treatment for A-fib is designed to control the symptoms of the condition, such as a racing, irregular heartbeat, and to prevent the risks of clots, strokes, and heart failure.
There are three basic types of A-fib:
- Paroxysmal: more common in the early stages of the condition, in which episodes occur every now and then.
- Persistent: when the irregular heartbeat lasts for more than 7 days.
- Permanent: when it is not possible to bring the heart back to a normal rhythm.
While episodes of paroxysmal A-fib might appear to go away, this is generally a long-term condition. According to the National Heart, Lung, and Blood Institute, multiple episodes of A-fib can actually change the heart's electrical system and make ongoing treatment necessary.
All individuals who have an episode of A-fib need to work with their doctors to keep a close watch on their heart health. They should do this even if they don't feel there is anything wrong, as sometimes people are not aware of their symptoms.
Most people who have the condition will need to take medication to manage their symptoms and reduce the risk of stroke.
For some, medication alone is not enough to control A-fib, and in these cases, more involved options, such as catheter ablation, surgical maze procedures, and electrical stimulation or, cardioversion, may be recommended.
Risks and side effects
Anticoagulants, commonly known as blood thinners, pose a risk of excessive bleeding.
Medications are very important for maintaining the health and well-being of people with A-fib.
However, there are risks associated with any medication. People should work closely with their doctor to make sure their drugs are working as they should.
In general, women should tell their doctors if they are breast-feeding, pregnant, or planning a pregnancy, due to the possibility of interactions with A-fib medications.
People taking anticoagulants should remember that these medications are designed to interfere with the body's ability to stop bleeding. They are more likely to bleed excessively as a result, and may need to cut back on certain activities.
A person should make sure their doctors, pharmacists, and dentists know they are taking such drugs, and watch for signs of unusual bleeding.
Beta-blockers can also cause insomnia, dizziness, impotence, cold hands and feet, and other side effects. They may also make people more sensitive to sunlight and cold weather. Grapefruit juice may affect the way the drugs work.
People taking antiarrhythmic drugs need to be aware that these can actually cause arrhythmia in some cases. In others, the drugs have been associated with serious damage to the lungs, liver, and thyroid, along with dizziness, difficulty seeing, and a "metallic taste."
A person should watch carefully for changes in their heart rate, vision, and weight. Lightheadedness, shortness of breath, and swelling of the feet or legs are known side effects of these kinds of medications.
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.
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.
Aspirin is only recommended for very low-risk A-fib patients. When aspirin is being used to address the heart arrhythmia, individuals should work with their doctors and take even this over-the-counter medication as prescribed.