A previously healthy 19-year-old male is brought to the emergency department by his girlfriend after briefly…

A previously healthy 19-year-old male is brought to the emergency department by his girlfriend after briefly losing consciousness. He passed out while moving furniture into her apartment. She said that he was unresponsive for a minute but regained consciousness and was not confused. The patient did not have any chest pain, palpitations, or difficulty breathing before or after the episode. He has had episodes of dizziness when exercising at the gym. Family history positive for his grandfather who died unexpectedly at age 28 years. The patient’s BP is 125/75 mm Hg while supine and 120/70 mm Hg while standing. Pulse is 70/min while supine and 75/min while standing. On examination, there is a grade 4/6 systolic murmur with PMI along the left lower sternal border and the apex, which disappears with passive leg elevation. What is the top differential diagnosis? Answers A-E А Mitral valve prolapse B Ehlers-Danlos syndrome o с Aortic regurgitation D Marfan syndrome E Hypertrophic cardiomyopathy O