Pulmonary Embolism USMLE Step 1 Practice Question
A 67-year-old man with chronic atrial fibrillation not on anticoagulation presents with acute dyspnea and syncope. Vital signs: BP 92/58, HR 118, RR 28, SpO2 88% on room air. Chest X-ray is clear. ECG shows new right axis deviation and T-wave inversions in V1-V4. D-dimer is elevated at 1.2 mcg/mL. He denies leg swelling. Which of the following is the most appropriate initial diagnostic test?
Answer choices
- AVentilation-perfusion scan
- BEchocardiography
- CLower extremity duplex ultrasound
- DD-dimer testing
- EComputed tomographic pulmonary angiographyCorrect answer
- FMagnetic resonance imaging of the chest
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