Which class of drugs is typically used for anticoagulation in atrial fibrillation?

• A. NOACs
• B. Warfarin
• C. Heparin
• D. Aspirin

Answer: (A)

Atrial fibrillation raises the risk of cardioembolic stroke because the irregular, rapid atrial contractions promote blood stasis and clot formation, especially in the left atrial appendage. The aim is long-term anticoagulation to prevent those clots from traveling to the brain.

Non–vitamin K antagonist oral anticoagulants (NOACs) are typically used because they’re effective for stroke prevention and offer a simpler, more predictable approach than warfarin: they start working quickly, come in fixed dosing without routine blood monitoring, and have fewer dietary and drug interactions. They also tend to have a lower risk of intracranial bleeding in many patients, which is a major advantage. This combination makes NOACs the preferred first-line choice for long-term anticoagulation in nonvalvular AF.

Warfarin is still appropriate in some circumstances, such as when NOACs aren’t suitable due to kidney function, cost, or certain valve diseases, or in patients with mechanical heart valves or significant rheumatic disease. Heparin is used mainly for short-term inpatient anticoagulation or bridging around procedures, not for chronic management. Aspirin alone does not provide adequate protection against stroke in atrial fibrillation and is not favored as the sole therapy for this indication.