Many patients with atrial fibrillation are at risk for stroke and need anticoagulation therapy. On Average, people with AFib have a stroke risk five to seven times higher than those who do not have AFib. AFib causes approximately 120,000 strokes each year in the United States. A stroke related to AFib happens when a clot breaks free, lodges in a blood vessel, and blocks the flow of blood and oxygen to the brain. One out of every 4 strokes is due to AFib. Because of the adverse effects a stroke can have on quality and duration of life, stroke prevention is a primary treatment goal in AFib.
There are a variety of treatments to prevent stroke, but a group of medications called anticoagulants are the most common “first-line” treatment. Anticoagulants are highly effective at lowering the likelihood of stroke related to AFib. Anticoagulants, which are sometimes called blood thinners, interrupt the blood’s normal clotting (coagulation) process. This complex system, which is called the coagulation cascade, involves many cells and proteins that work together to stop bleeding. There are several oral medications available for patients with AFib, including Vitamin K antagonists, Direct thrombin inhibitors, and Factor Xa inhibitors. Anticoagulants target different parts of the coagulation cascade so blood clots cannot form. However some patients have a high risk of bleeding with long term use of this type of therapy. This is especially true if the patient is frail or has a history of bleeding, such as bleeding in the stomach or intestines and/or brain (cerebral hemorrhage). New medications and procedures are available to help manage the risks of both stroke and bleeding in these patients with atrial fibrillation. When taken as prescribed, all anticoagulants significantly reduce the risk of stroke due to blood clots. Patients taking anticoagulants are at risk for excess bleeding because the medications interrupt coagulation and prevent clotting. Each type of anticoagulant has its own benefits and risks.
Atrial Fibrillation Stroke Risk Animation, Courtesy of Medtronic.