What is the role of digoxin in heart failure management?

• A. Positive inotrope and negative chronotropic agent.
• B. Negative inotrope and positive chronotropic agent.
• C. Calcium channel blocker.
• D. Vasodilator.

Answer: (A)

Digoxin combines two key actions that fit heart failure management: a positive inotropic effect and a negative chronotropic effect. It inhibits Na+/K+-ATPase in cardiac myocytes, which raises intracellular calcium during systole and strengthens each heartbeat (positive inotropy). At the same time, it increases vagal tone, slowing conduction through the AV node (negative chronotropy). This combination improves cardiac output and can relieve symptoms and improve exercise tolerance, especially in heart failure with reduced ejection fraction and when atrial fibrillation is present to help control the ventricular rate. It’s not a calcium channel blocker or a vasodilator, and its main clinical use centers on symptom relief and rate control rather than primary mortality reduction. Toxicity risk and a narrow therapeutic window are important considerations.