Congenital Heart Disease USMLE Step 1 Practice Question
A 19-year-old man presents with refractory hypertension despite lisinopril monotherapy. Vital signs reveal BP 165/98 mmHg bilaterally, HR 88/min, RR 16/min. Physical examination demonstrates weak femoral pulses and delayed lower extremity capillary refill. Chest radiograph shows notching of the inferior rib borders and a narrowed aortic knob. Serum creatinine is 1.2 mg/dL. Femoral-brachial pulse delay is present. Which of the following best explains these radiographic findings?
Answer choices
- AChronic osteomyelitis of the ribs from bacteremia
- BCalcification of costal cartilage due to chronic hypercalcemia
- CDilation of pulmonary arteries causing extrinsic rib compression
- DCompression fractures due to osteoporosis
- EErosion by enlarged intercostal arteries acting as collateral vesselsCorrect answer
- FNeurofibromatosis type 1 causing dysplasia of the rib cortex
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