Which medication is primarily used for rate control in atrial fibrillation?

Beta-blockers are primarily used for rate control in atrial fibrillation because they effectively reduce the heart rate by blocking the action of epinephrine and norepinephrine on beta-adrenergic receptors. In atrial fibrillation, the heart rate can become excessively rapid due to irregular electrical activity in the atria, and beta-blockers help to slow down the conduction through the atrioventricular (AV) node. This rate control is essential for managing symptoms and improving hemodynamic stability in patients.

While digoxin can also help control the heart rate, particularly in patients with heart failure, it is generally considered a second-line agent in this context. Adenosine is primarily used for acute termination of certain types of supraventricular tachycardias and is not effective for long-term rate control in atrial fibrillation. Calcium channel blockers can also be effective for rate control, especially in rapid ventricular rates, but beta-blockers are more commonly the first choice due to their additional cardiovascular protective effects and better overall outcomes in managing atrial fibrillation.