FCEM2-0158

A 25-year-old woman comes in with a complaint of palpitations that occur during her regular jogging routine. Her mother passed away at a young age from an unknown cause. During the examination, her pulse feels irregular and there is a presence of a double apical impulse. A systolic murmur can be heard at the left sternal edge that spreads throughout the praecordium.

What is the SINGLE most probable diagnosis?