But you might be better off with a newer type of blood-thinning medication, such as Xarelto (rivaroxaban), Pradaxa (dabigatran), Eliquis (apixaban), or Savaysa (edoxaban) — collectively known as non–vitamin K antagonist oral anticoagulants, or NOACs. In January 2019, the American Heart Association, the American College of Cardiology, and the Heart Rhythm Society joined together to recommend NOACs as the preferred alternative to warfarin in a focused update to their atrial-fibrillation guideline. The original guideline treated NOACs and warfarin as equivalent. People with moderate to severe mitral stenosis (narrowing of the heart’s mitral valve) or a mechanical heart valve are a special case. “If these patients have afib, they should continue to receive warfarin rather than a NOAC,” says Craig T. January, MD, PhD, cochair of the focused update and professor of cardiovascular medicine at the University of Wisconsin in Madison.
Why Blood Thinners Are Essential for People With Afib
Both warfarin and NOACs reduce the risk of thromboembolism (a blockage caused by a blood clot), which is the most serious concern with atrial fibrillation. When the atria (the upper two chambers) of the heart fibrillate (quiver) rather than beat with a regular “lub-dub, lub-dub, lub-dub” pattern, blood can pool and clot in a section called the left atrial appendage. “If a blood clot forms and breaks off, it will travel out of the heart and go somewhere,” Dr. January says. “The most common place is to the brain” — potentially causing a stroke. “Stroke is the big concern in afib, and afib-related strokes tend to be big strokes.” Medication can help reduce the danger, though with potential side effects: Both warfarin and NOACs can cause spontaneous bleeding or major hemorrhage anywhere in the body. But after reviewing the evidence, “It was the committee’s feeling that the data continues to support the idea that NOACs have less bleeding risk than warfarin,” January says. NOACs are safer than warfarin, he adds, because they work more predictably to interrupt the blood-clotting process from a pharmacological perspective.
Bonus: NOACs Are User-Friendly
NOACs are also easier to manage than warfarin. While warfarin requires frequent monitoring at home or in a clinic to assess the blood’s ability to clot, with NOACs you take a pill once or twice a day and you’re done, following up with your doctor at your regular checkups. Another plus of NOACs is that while you’re taking them you can eat as much as you want of any green vegetable, such as spinach, kale, or broccoli. Patients on warfarin must avoid these foods because they’re high in vitamin K, which can block the drug. The downside of NOACs? They aren’t yet routinely covered by health insurance (check your policy) and might require out-of-pocket payments of up to several hundred dollars per month. If you have afib and need an anticoagulant medication but can’t afford NOACs, January advises taking warfarin, which is routinely covered by insurance. Don’t go without.
Another Way to Assess Blood-Thinner Need
In addition to prioritizing NOACs over warfarin, the focused update also recommends that people with afib take anticoagulant medication if they have an elevated CHA2DS2-VASc score, which is an assessment tool doctors can use to determine stroke risk in people with afib. “There are patients with afib who are not on an anticoagulant — we encounter them regularly,” January says. “But if you have afib, sustained or intermittent, and you have an elevated CHA2DS2-VASc score, you belong on an anticoagulant.”
