Arrhythmias USMLE Step 1 Practice Question
A 72-year-old man with COPD presents with palpitations and dyspnea. Vital signs: BP 138/82 mmHg, HR 150/min, RR 22/min, SpO2 94% on room air, temperature 37.2°C. ECG reveals regular atrial activity at 300 bpm with characteristic sawtooth flutter waves and ventricular rate of 150 bpm. Troponin is normal. He denies chest pain. Which of the following is the most likely diagnosis?
Answer choices
- ATorsades de pointes
- BCardiogenic shock
- CAV nodal reentrant tachycardia
- DWolff Parkinson White syndrome
- EAtrial flutterCorrect answer
- FAtrial fibrillation with rapid ventricular response
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