Autonomic Pharmacology USMLE Step 1 Practice Question
A 63-year-old man with a history of hypertension and hyperlipidemia presents to the emergency department with crushing substernal chest pain radiating to his jaw that began 90 minutes ago. An ECG demonstrates ST-segment elevations in leads II, III, and aVF consistent with an inferior wall myocardial infarction. His blood pressure is 88/60 mmHg, heart rate is 38 beats per minute, and oxygen saturation is 94% on room air. On physical exam, he is diaphoretic and appears pale. Cardiology is emergently consulted, and while the patient is being prepared for temporary transvenous pacing, the treating physician administers a drug that increases heart rate and contractility through beta-1 stimulation and also causes skeletal muscle vasodilation through beta-2 stimulation. Which of the following agents was most likely administered?
Answer choices
- AIsoproterenolCorrect answer
- BAcetylcholine
- CMethyldopa
- DEpinephrine
- EPhenylephrine
- FAtropine
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.