In atrial fibrillation management, anticoagulation is guided by CHA2DS2-VASc score to reduce the risk of which event?

• A. To reduce risk of myocardial infarction
• B. To reduce risk of stroke
• C. To reduce risk of pulmonary embolism
• D. To reduce risk of death

Answer: (D)

The key idea is that anticoagulation in atrial fibrillation is used to prevent a cardioembolic stroke. In AF, the irregular rhythm allows blood to pool in the atria, especially the left atrial appendage, which can form clots. If a clot travels to the brain, it can cause an ischemic stroke. The CHA2DS2-VASc score estimates the annual risk of stroke or systemic embolism in people with nonvalvular AF and guides whether to start anticoagulation. A higher score means a greater stroke risk and a greater expected benefit from anticoagulation. While anticoagulation can influence overall outcomes, its primary established purpose in this context is to reduce the risk of ischemic stroke, not myocardial infarction or pulmonary embolism.