Recent decades have seen a blossoming of the science around controlling the dangerous form of irregular heartbeat known as atrial fibrillation or “A-fib”. Pioneering physicians continue to develop new surgical techniques as well as medications to treat the condition, which is closely associated with an elevated risk of stroke. A-fib medications may be used either to help control the heart’s rate or to correct its abnormal rhythm. Some of these medications must be taken indefinitely, and often the choice of treatment is not surgery versus atrial fibrillation medication, but rather both a procedure and at least one medication.

Which to address first: Rate or rhythm

When a doctor and patient are developing a treatment plan together, one of the key questions that must be addressed is whether to focus more on getting the heart’s rate (number of beats per minute) under control, or seeking to fix its abnormal rhythm. Sometimes this choice is an easy one because symptoms are so severe that the faulty rhythm must be addressed. In other cases, there’s more ambiguity. Because the drugs that help control the heart’s rhythm are often poorly tolerated, doctors and patients might be less inclined to turn to them, preferring instead to get relief by slowing down their heart rates despite the continued arrhythmia.

Anticoagulants are key to A-fib treatment

Whether your recommended A-fib treatment starts with controlling your heart’s rate or rhythm, or surgically or through medication, your doctor is likely to want you to go on an anticoagulant medication, otherwise known as a blood thinner. The great risk associated with A-fib is that the quivering rhythm of the heart’s atria don’t allow the chambers to empty sufficiently, leaving blood behind that can pool, form clots, travel to the brain, and cause a stroke. Most A-fib patients will therefore be put on an anticoagulant, probably for life. Anticoagulants are observed to decrease stroke risk in A-fib patients by somewhere between 50% and 80%.

Anticoagulants include…

  • Warfarin. Although it was the drug of choice for decades, these days warfarin (Coumadin) is being eclipsed by newer medications that are easier to take. People on warfarin have to control their intake of vitamin-K rich foods such as broccoli, kale, and spinach, too much of which can undo the drug’s effectiveness in suppressing the blood’s clotting factors. Warfarin also interacts negatively with many common drugs, including alcohol. However, it is very affordable, which is one reason why it is still used today.
  • NOACs/DOACs. Warfarin’s recent replacements are referred to either as novel oral anticoagulants (NOACs) or direct oral anticoagulants (DOACs). The efficacy of these drugs is less affected by your diet or other medications, and they’re just as effective as warfarin in preventing stroke. Examples of NOACs/DOACs include rivaroxaban (Xarelto), apixaban (Eliquis), edoxaban (Savaysa), and dabigatran (Pradaxa). One downside to these drugs compared to warfarin is that, while they take effect more quickly, they also wear off more quickly and thus should be taken at the same time every day.

Controlling the heart rate

If you and your doctor choose a rate-control strategy for you’re A-fib, it will likely be centered on one of three types of medications:

  • Calcium channel blockers. These drugs work by slowing down the electrical impulses in the heart. Calcium channel blockers (CCBs) are prescribed for other uses besides atrial fibrillation. The two CCBs prescribed for A-fib are verapamil (Verelan) and diltiazem (Tiazac, Cardizem, and Cartia). People taking CCBs sometimes experience fluid buildup, dizziness, constipation, flushing, and headache.
  • Beta-blockers. Like calcium channel blockers, beta-blockers are used widely for numerous cardiovascular conditions. They also have a similar effect on the electrical impulses in the heart. Examples include metoprolol (Lopressor or Toprol), bisoprolol, propranolol (Hemangeol or Inderal), atenolol (Tenormin), carvedilol (Coreg), and nadolol (Corgard). People on beta-blockers may experience depression, headache, fatigue, erectile dysfunction, worsening of existing asthma, and cold feet and hands.
  • Digoxin. This drug, licensed commercially as Lanoxin, is rarely prescribed anymore since CCBs and beta-blockers are safer and more effective. It works by making each heartbeat more powerful but slower. It’s sometimes still prescribed to people who aren’t able to take beta-blockers or CCBs, but should be avoided by people with kidney problems. Its side effects include vomiting, weakness, changes in mood, dizziness, anxiety, nausea, and headache.

Controlling your heart rhythm

If your treatment choice is to attempt to restore the heart’s normal rhythm through medication, your doctor will prescribe a type of drug known as an antiarrhythmic. These work by resetting the heart’s rhythm in a way similar to restarting a computer to correct a malfunction, or they may be prescribed to help maintain the normal rhythm after such a reset is performed through a procedure known as cardioversion. Antiarrhythmics include disopyramide (Norpace), solatol (Betapace), dronedarone (Multaq), amiodarone (Nexterone), flecainide, dofetilide (Tikosyn), and propafenone (Rhythmol SR).

It’s easy to imagine that everyone with A-fib should simply take an antiarrhythmic to correct the condition, but the truth is more complex than that. These drugs have a variety of side effects and must be administered with close monitoring of their effects on liver and kidney function. In fact, people are often hospitalized when the drugs are first administered so that they can be watched very closely. And, counterintuitively, sometimes putting a person on an antiarrhythmic can trigger new electrical disturbances in the heart or exacerbate the existing arrhythmia.

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