Arrhythmias USMLE Step 1 Practice Question
A 19-year-old man presents with recurrent episodes of palpitations and syncope. Vital signs show BP 118/76 mmHg, HR 92 bpm, RR 16/min, temp 37°C, SpO2 98% on room air. Resting ECG demonstrates a short PR interval (100 ms) and slurred upstroke of the QRS complex. Echocardiogram shows normal ventricular function with no structural abnormalities. He denies chest pain or dyspnea. Which of the following is the most likely diagnosis?
Answer choices
- ATorsades de pointes
- BAtrial flutter
- CWolff Parkinson White syndromeCorrect answer
- DAV nodal reentrant tachycardia
- ECardiogenic shock
- FBrugada syndrome
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