Arrhythmias USMLE Step 1 Practice Question
A 72-year-old man with chronic atrial fibrillation and CKD stage 3 is found to have a heart rate of 110 bpm at rest. He is currently on diltiazem. His digoxin level is 2.8 ng/mL (therapeutic range 0.8-2.0). He reports nausea, visual disturbances, and palpitations. Which of the following is the most likely diagnosis?
Answer choices
- AAcute decompensated heart failure
- BDigoxin toxicityCorrect answer
- CThyroid storm
- DInadequate rate control of atrial fibrillation
- ESepsis
- FDiltiazem-induced bradycardia with compensatory tachycardia
See the full explanation
Get the correct-answer rationale, why each distractor is wrong, the underlying mechanism, and high-yield associations — plus adaptive practice that targets your weak areas — with a free MedBoardPRO account.