A 58-year-old male undergoes coronary artery bypass grafting. On post-operative day 3, he develops new-onset atrial fibrillation with rapid ventricular response (HR 130 bpm). He is hemodynamically stable. Which of the following is the most appropriate initial management?

✓ Correct Answer: Option B

Postoperative atrial fibrillation with rapid ventricular response is common and usually transient. Since the patient is hemodynamically stable, rate control with intravenous beta-blockers (e.g., metoprolol) or non-dihydropyridine calcium channel blockers (e.g., diltiazem) is the preferred initial approach.