A 58-year-old man with heart failure and reduced ejection fraction (LVEF 30%) is on guideline-directed medical therapy. His resting heart rate remains 78 bpm despite maximally tolerated carvedilol. Which drug, proven to reduce heart failure hospitalizations when added to beta-blockers, acts by selective If channel blockade in the sinoatrial node?
- A Verapamil
- B Diltiazem
- C Ivabradine ✓
- D Digoxin
Correct answer: C. Ivabradine
Explanation
Ivabradine selectively blocks the If (funny) current in the sinoatrial node, reducing heart rate without negative inotropy or hypotension. The SHIFT trial demonstrated reduced heart failure hospitalizations when ivabradine was added to beta-blockers in patients with HR ≥70 bpm and sinus rhythm. Verapamil and diltiazem are non-dihydropyridine calcium channel blockers contraindicated in HFrEF. Digoxin reduces hospitalizations but does not selectively block If channels.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.