A young basketball player with a height of 188 cm and armspan 197 cm has a diastolic murmur best heard in second right intercostal space. The likely cause of murmur is:

This patients arm span is greater than height, which is suggestive of Marfan's syndrome. Aoic regurgitation as well as diastolic murmur in second right intercostal space are features associated with Marfan's. Ref: Mosby's Handbook of Patient Teaching By Mary.M. Canobbio, Page 60 ; Harrison's Principle of Internal Medicine, 16th Edition, Page 2329