USMLE Step 2 - Question 2

An 18 year old male with no significant past medical history presents to his primary care physcician for a routine physical examination. He has no physical complaints. His blood pressure is 115/85, heart rate 80, respirations 12, and he is afebrile. His physical examination reveals normal lung sounds, a V/VI holosystolic murmur with a thrill at the left lower sternal border and no change in intensity with inspiration, no gallops or extra heart sounds and normal jugular venous pressures. His ECG and laboratory studies are normal. What is his most likely diagnosis?

A. Mitral regurgitation

B. Patent ductus arteriosis

C. Tricuspid regurgitation

D. Ventricular septal defect