A 13-year-old girl is brought to the physician for a follow-up appointment. She has a 1/6 systolic murmur auscultated at the upper chest, right-axis deviation on ECG, and a second heart sound that doesn’t oscillate. She is not cyanotic. Chest x-ray shows increased pulmonary vascularity. Which of the following is the most likely explanation for this patient’s findings?
A) Aortic stenosis
B) Myxoma
C) Patent foramen ovale
D) Pulmonic stenosis
E) Venous hum
