Cardiovascular Drugs USMLE Step 1 Practice Question
A 65-year-old woman with a history of paroxysmal supraventricular tachycardia presents with palpitations, dyspnea, and chest discomfort. Vital signs show BP 138/82 mmHg, HR 178 bpm, RR 20/min, and SpO2 98% on room air. ECG demonstrates a narrow-complex tachycardia. She denies prior myocardial infarction. She is initiated on a medication that slows conduction through the atrioventricular node by decreasing L-type calcium current. Which drug has this mechanism of action?
Answer choices
- AAmiodarone
- BVerapamilCorrect answer
- CProcainamide
- DAdenosine deaminase
- ELidocaine
- FDiltiazem
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