A 30-Year-Old Man with a Family History of Sudden Cardiac

A 30-year-old man with a family history of sudden cardiac death has a systolic murmur that increases in intensity when he is sitting up. An echocardiogram shows abnormal movement of the anterior mitral valve leaflet against an asymmetrically thickened interventricular septum. The mechanism for sudden cardiac death in this patient's family is most closely attributed to which of the following conditions?

A) Acute myocardial infarction (MI)
B) Congenital bicuspid aortic valve
C) Conduction system defect
D) Dissecting aortic aneurysm
E) Mitral valve prolapse (MVP)