A 79-year-old man with a history of chronic systolic heart failure and atrial fibrillation presents to the emergency department with a 2-day history of nausea, vomiting, confusion, and yellow-tinged vision. His current medications include digoxin 0.25 mg daily and furosemide 40 mg daily. Vital signs reveal BP 128/76 mmHg, HR 102 bpm with an irregular rhythm, RR 18 breaths/min, and temperature 37°C. On examination, he appears lethargic and mildly diaphoretic. Serum digoxin level is 3.2 ng/mL (therapeutic range: 0.5–2.0 ng/mL), BUN is 28 mg/dL, and creatinine is 1.8 mg/dL, suggesting mild renal impairment contributing to drug accumulation. Serum potassium is 4.1 mEq/L. ECG demonstrates frequent premature ventricular contractions with occasional bigeminy. Which agent is most appropriate for treatment of this patient's severe digoxin toxicity?

1. A)Deferoxamine
2. B)Atropine alone
3. C)Digoxin specific antibody fragmentsGABARITO
4. D)Vitamin K
5. E)Protamine sulfate