She was 26 and had spent six months getting progressively more breathless. Physical activity brought on fatigue and chest pain. By the time she was assessed, her limitation was severe enough to place her in New York Heart Association class III, the category for marked restriction of ordinary activity.
She reported no significant medical history and no family history of heart disease. What she had was a band of muscle inside her heart, congenital in origin, that had been quietly dividing her right ventricle into two chambers.
