Arrhythmias USMLE Step 1 Practice Question
A 67-year-old man comes to the emergency department because of palpitations and mild shortness of breath that began this morning. He has hypertension and coronary artery disease. Pulse is 150 per minute and regular. ECG shows narrow QRS complexes with an atrial rate of about 300 per minute and sawtooth flutter waves in the inferior leads. Which of the following is the most likely diagnosis?
Answer choices
- AAtrial flutterCorrect answer
- BMultifocal atrial tachycardia
- CAtrial fibrillation
- DSinus tachycardia
- EAV nodal reentrant tachycardia
- FAtrial tachycardia with 2:1 atrioventricular block
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