Treatments Reduce Stroke Risk in People with Atrial Fibrillation
If you are one of the millions of people in the U.S. with atrial fibrillation (or AFib), your risk for stroke is much higher than people without the heart rhythm disorder. Yet many people with AFib are not taking advantage of newer medications and devices that reduce that risk more effectively than ever. Here, Kevin Jackson, MD, and James P. Daubert, MD, Duke electrophysiologists who specialize in caring for people with arrhythmias like AFib, discuss these treatments and how they lower stroke risk in people with AFib.
Older Medication Was a Hassle
The rapid, irregular heartbeats that define atrial fibrillation can allow blood clots to form in your heart and travel to your brain, causing a stroke. Until about 2010, doctors routinely prescribed a medication called warfarin (Coumadin) to thin the blood and reduce the risk of stroke. However, warfarin requires frequent blood tests to monitor whether the drug is thinning the blood too much or not enough. Diet is a concern too, since vitamin K found in foods like green leafy vegetables inhibits warfarin’s effectiveness. These issues make some people unwilling to take warfarin.
“Although warfarin is an effective blood thinner with a long track record, it’s a difficult drug for patients to manage. When warfarin levels get too low, patients are at risk for stroke. When levels are too high, the risk of bleeding increases significantly. Patients and doctors were eager for better options.”
Safer, More Effective Anticoagulants
Over the last decade or so, several new stroke-prevention medications have been approved by the FDA for people with AFib. They’re called direct-acting oral anticoagulants (DOACs), and they are proven to be safer than warfarin, while performing as well or better in reducing stroke risk in people with AFib. DOACs more consistently thin the blood, and there are no dietary restrictions. Also, reversal agents are widely available in cases of emergency.
Duke doctors were involved in studies that led to FDA approval for two of the newer drugs, rivaroxaban (Xarelto) and apixaban (Eliquis). Dr. Jackson explained, “The new anticoagulants are a significant improvement over warfarin. They thin the blood quickly and consistently and don’t require regular monitoring. We have found them to be safe and well-tolerated by patients.”
Devices Prevent Blood Clots from Forming
For people who can’t take anticoagulants long-term, left atrial appendage occlusion devices can protect against stroke. The left atrium is one of the two top chambers of the heart. “The left atrial appendage is like a little cul-de-sac off the left atrium,” Dr. Daubert explained. “When you are in atrial fibrillation, and the atrium isn’t vigorously contracting, blood can stagnate and form a clot, which can cause a stroke." These devices, which are placed during a minimally invasive catheterization procedure, block the left atrial appendage and prevent clots from escaping.
Duke was the first North Carolina hospital to implant a left atrial appendage occlusion device called the WATCHMAN, which uses a parachute-type mechanism to block the opening of the left atrial appendage. “These procedures help address the risk of stroke in the substantial portion of patients with atrial fibrillation who are either not taking, are not good candidates for, or are at high risk with continual anticoagulation therapy,” Dr. Daubert said.
