CNS Pharmacology USMLE Step 1 Practice Question
A 28-year-old man with Wolff-Parkinson-White syndrome presents with episodic palpitations and is found to have antidromic atrioventricular reentrant tachycardia. Vital signs: BP 128/82 mmHg, HR 160 bpm, RR 16, Temp 37°C, SpO2 98% on room air. He is hemodynamically stable with no prior syncope. ECG shows a wide QRS complex with antidromic conduction. Which intravenous agent prolongs action potential duration and refractory period in atrial and ventricular myocardium?
Answer choices
- ADigoxin
- BVerapamil
- CProcainamideCorrect answer
- DAtropine
- EAdenosine only because it increases AV nodal conduction
- FIbutilide
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