Autonomic Pharmacology USMLE Step 1 Practice Question
A 68-year-old man with decompensated systolic heart failure is admitted for cardiogenic shock after a large myocardial infarction. His blood pressure is 82/50 mmHg, heart rate is 112 beats per minute, and cardiac output is severely reduced on right heart catheterization. He is cold and clammy with bibasilar crackles, low urine output, and an ejection fraction of 20% on bedside echocardiography. A drug is started that primarily stimulates beta-1 receptors and increases cardiac output with relatively little change in systemic vascular resistance. Which of the following agents was most likely used?
Answer choices
- APhenylephrine
- BDobutamineCorrect answer
- CPrazosin
- DNorepinephrine
- EClonidine
- FMilrinone
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