Gross Anatomy USMLE Step 1 Practice Question
A 50-year-old man presents with acute dysphagia and substernal chest pain after swallowing a large piece of meat. Vital signs: BP 128/82, HR 92, RR 18, Temp 37.2°C, SpO2 98% on room air. Chest X-ray shows a meat bolus lodged in the thoracic esophagus at the level of the sternal angle. No aspiration or perforation is noted. He denies recent weight loss or difficulty swallowing liquids. Compression by which anatomic structure most likely contributes to this normal site of esophageal narrowing?
Answer choices
- ALower esophageal sphincter
- BThoracic duct
- CInferior vena cava
- DCricopharyngeus muscle
- EAortic arch and left main bronchusCorrect answer
- FLeft atrium
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