Coronary Artery Disease USMLE Step 1 Practice Question
A 76-year-old woman with hypertension presents with repeated episodes of lightheadedness and intermittent palpitations followed by prolonged pauses. Vital signs show BP 142/88 mmHg, HR 48 bpm, RR 16, temp 37°C, SpO2 98% on room air. Electrocardiographic monitoring reveals periods of sinus bradycardia alternating with atrial fibrillation. Troponin is normal. She denies chest pain. Which of the following is the most likely diagnosis?
Answer choices
- AVentricular fibrillation
- BWolff Parkinson White syndrome
- CMobitz type I AV block
- DSick sinus syndromeCorrect answer
- EAtrial flutter only
- FComplete heart block with junctional escape rhythm
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