Organ System Pathology USMLE Step 1 Practice Question
A 2 month old boy is brought in for poor feeding and tachypnea. Examination reveals a harsh holosystolic murmur best heard at the left lower sternal border. Echocardiography shows a defect in the membranous interventricular septum with left to right shunting. Which of the following is the most likely diagnosis?
Answer choices
- ATricuspid atresia
- BTetralogy of Fallot
- CAtrial septal defect
- DVentricular septal defectCorrect answer
- EPatent ductus arteriosus
- FAtrioventricular septal defect from endocardial cushion fusion failure
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