Review Question - QID 212639

A 28-year-old man presents to your primary care office to establish care. He feels well but has not seen a physician in several years. Past medical history is notable for a chronic heart murmur and prior gonorrheal and chlamydial infections (both successfully treated with antibiotics). He was adopted as a young child and has never met his biological parents. A diastolic murmur, tall stature, and joint hypermobility are noted on physical exam. A photograph of the patient’s chest is shown below (Figure A). Which of the following etiologies best explains this patient’s heart murmur?