My 11 year old has a bicuspid aortic valve. She has never had to wear a holter.
For the majority of people they are fine until they are in their 40's.
My dd is in the minority. She was diagnosed at 11 months and had appointments with the cardio every 2 years until she was 7 and started getting cheat pains during exercise(and walking). She started going every 6 months.
She now has regurgitation with her aortic valve. They figure she will nee a valve replacement before she is out of her teens. A valve replacement is no longer open heart surgery. They have a 2-3 day hospital stay and a much shorter recovery.
She used to be on restricted physical activities but no longer is. She can't do sports like weight lifting or judo and they would prefer no varsity type sports.
She dances 5 hours a week and plays soccer, volleyball, basketball, track in grade 6.
When she sees her cardio twice a year they do a ecg, echo and treadmill stress test. It's about a 4 hour appointment, 90% of which is is waiting.