Preventing stroke is the top priority if your heart is beating irregularly. A variety of options can control symptoms.
A flutter in the chest and a racing heartbeat could be just a passing cardiac blip, perhaps triggered by emotional stress or too much caffeine. But sometimes it’s a sign of atrial fibrillation—the irregular quivering of the heart’s upper chambers, or atria.
The first priority with any new case of atrial fibrillation (afib) is to determine if you need to take a blood thinner (anticoagulant) to prevent strokes. “In atrial fibrillation, you’re at risk of clots forming in the heart, which can go anywhere in the body but predominantly go to the brain,” says Dr. Christian Ruff, a cardiologist at Harvard-affiliated Brigham and Women’s Hospital. “Most people will end up taking an anticoagulant for life, which can reduce their risk of stroke between 60 and 80 percent.”
Some of the three million to six million Americans with atrial fibrillation (afib) may also need treatment to correct the faulty rhythm if it causes bothersome symptoms, like chest discomfort and shortness of breath.
What afib feels like
The most common symptom of a new case of afib is a rapid heartbeat. Other signs of afib include chest pain or pressure, dizziness, faintness or confusion, fatigue when exercising, fluttering or thumping in the chest, shortness of breath, anxiety, sweating, or weakness. Some people with afib feel no symptoms, but tests show the rhythm is off.
The abnormal rhythms may come and go—daily or just occasionally. Sometimes the heart will go back to its normal rhythm by itself. Other episodes might last for days or not go away at all without medical treatment. Afib tends to worsen over time and become chronic. “People generally go in and out of afib, and then eventually most will just stay in it unless treated,” Dr. Ruff says.
It’s not always clear what triggers afib episodes, but studies point to a long list of factors that may contribute. Drinking too much alcohol is one. Untreated high blood pressure or disordered nighttime breathing (obstructive sleep apnea) are other common culprits.
When the heart beats out of rhythm, blood can stagnate and form clots in the upper chambers of the heart. Taking an anticoagulant makes this less likely to happen.
For decades, the mainstay of anti-clotting drugs has been warfarin (Coumadin), but new drugs are coming into use that have potential advantages. They are apixaban (Eliquis), dabigatran (Pradaxa), edoxaban (Savaysa), and rivaroxaban (Xarelto).
Clinical trials have demonstrated that the new drugs are as effective as warfarin for preventing strokes, but they interact less with food and other drugs. That means there’s no need for regular monitoring of clotting function (and frequent dose adjustments) to make sure you take enough warfarin to prevent strokes without causing excessive bleeding.
All anticoagulants—old and new—come with a risk of unwanted bleeding. If a blood vessel springs a leak, chemicals in the blood called clotting factors come to the rescue. Interfering with that process to prevent strokes also slightly increases the chance of excessive bleeding. “All anticoagulants have to be used carefully,” Dr. Ruff says.
In clinical trials, the new anticoagulants did not raise the risk of unwanted bleeding any more than warfarin did, and actually substantially lowered the risk of serious and life-threatening bleeding—particularly bleeding in the brain, which is often fatal.
You and your doctor need to weigh both the pros and cons of the warfarin alternatives—and it’s not a simple decision. For example, unlike with warfarin, there is currently no way to rapidly reverse the effect of the new anticoagulants if unwanted bleeding happens. Warfarin does have such an antidote: a shot of vitamin K.
On the other hand, Dr. Ruff points out, clinical trials found that people taking the new drugs were less likely than those taking warfarin to experience the most serious risk of anticoagulants (brain bleeding) in the first place, despite the lack of an emergency “off switch” like warfarin’s vitamin K.
Men already taking warfarin successfully may decide to stay with it, while others may prefer the newer drugs for the lower risk of brain bleeding and an end to constant checks of clotting function. Not surprisingly, the advantages come at a cost: the new anticoagulants take effect faster but wear off sooner, so it’s especially important to take the pill on schedule every day.
Rate or rhythm control?
Once a person starts taking an anticoagulant, the longer-term goal is to get afib symptoms under control. The first-choice drugs for this are beta blockers and calcium-channel blockers, which slow down too-fast heartbeats. That strategy is known as rate control. “As long as they are at a slow heart rate, people with afib generally feel fairly well,” Dr. Ruff says.
Sometimes damping down heart rate is not enough. If the afib continues to be bothersome or worsens, a type of medication called an anti-arrhythmic may help. This strategy, called rhythm control, tries to restore a normal rhythm rather than just slowing the heart down to reduce discomfort. But anti-arrhythmics have more side effects than rate control drugs, and often they don’t work well.
When medications fail, or if the drug side effects are worse than the cure, a minimally invasive procedure called catheter ablation might be considered. Ablation destroys the spots in the heart that trigger the episodes of afib. The hitch is that many men require multiple procedures. In some cases, a cardiologist may recommend early ablation rather than trying rhythm control drugs.
Tips for using warfarin safely
Although alternative blood thinners are now available, many people with atrial fibrillation take warfarin (Coumadin) and may choose to continue if they are doing well. Here are some tips for using this medication safely and effectively: