Anticoagulation and Atrial Fibrillation

Why is Anticoagulation Important?

Atrial fibrillation is a serious cardiac condition that increases your likelihood of stroke by five times²⁷. Since the atria cannot pump with sufficient pressure during episodes of AF, small amounts of blood may pool in the left atrial appendage. This can lead to a stationary blood clot (or atrial thrombus) which can eventually work its way into the bloodstream (becoming an arterial embolism) and the brain. The likelihood of stroke jumps to seventeen times if you suffer from atrial fibrillation and rheumatic heart disease.⁴⁷ Current research estimates that 35% of patients with atrial fibrillation will suffer a stroke.²⁸

Anticoagulation medications are the most commonly used treatment options for reducing the risk of stroke among patients with atrial fibrillation. Anticoagulants have been shown in clinical trials to reduce the risk of embolic stroke by 68%⁴⁵ for most patients with atrial fibrillation and up to 83%⁴⁸^,⁴⁹ in patients with no concomitant heart disease. Anticoagulants have also been shown to reduce the risk of any recurrent ischemic stroke up to 70%⁵⁰. To achieve this level of protection, it is important to maintain the correct level of anticoagulant in your blood – too little and clots can form; too much and severe bleeding problems can occur.

Anticoagulants

Anticoagulants are often referred to as blood thinners. There are three main types of anticoagulants:

• Inhibitors of Clotting Factor Synthesis such as Coumadin® (warfarin), an oral medication

• Thrombin Inhibitors such as Heparin, which is injected intravenously

• Antiplatelets such as aspirin or Plavix® (clopidogrel bisulfate tablets)

Anticoagulants are prescribed for a variety of reasons. Coumadin is one of the top twenty most prescribed drugs in the United States and is the most widely prescribed anticoagulant for minimizing the risk of stroke in patients with atrial fibrillation. While Coumadin and other anticoagulants may prevent new clots from forming and existing clots from increasing in size, they do not dissolve clots that have already formed, and they do not address the symptoms or causes of atrial fibrillation. These medications also have side effects, require strict adherence to a complex set of guidelines for safety and effectiveness, and require continued medical monitoring by a physician.

If you are considering Coumadin as one of your treatment options for atrial fibrillation, it is important that you understand how this drug therapy will affect your life and your health:

• Learn more about Coumadin (warfarin)
• Coumadin Precautions
• Coumadin and Your Diet
• Potential risks and side effects
• Coumadin Resources

Coumadin^® and Plavix^® are registered trademarks of Bristol-Myers Squibb. For the most recent information about these drugs, please visit www.bms.com.

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