Which pairing correctly matches a cardioactive drug with its common indication?

• A. Digoxin — congestive heart failure
• B. Digoxin — tachyarrhythmia
• C. Amiodarone — hypotension
• D. Verapamil — pulmonary edema

Answer: (A)

Cardioactive drugs are chosen by the condition they most effectively treat. Digoxin increases heart muscle contraction by inhibiting Na+/K+ ATPase, which raises intracellular calcium and strengthens systolic performance. It also slows conduction through the AV node, aiding rate control in tachyarrhythmias. The classic, most common indication for digoxin is congestive heart failure, where stronger contractions improve cardiac output and symptoms. While it can be used for rate control in some tachyarrhythmias, and other drugs like amiodarone and verapamil have their own roles, the pairing with congestive heart failure best reflects its primary clinical use. Amiodarone treats various arrhythmias but hypotension is not its indication, and verapamil is not used to treat pulmonary edema and can worsen heart failure in acute decompensation.