Welcome to HCM.
The reason to correct reflux is to save the kidneys due to damaging effect of the reflux of urine to the kidneys.
The kidneys could well have been affected by the reflux already and hence renal atrophy
is quite possible.
We usually check kidney function ( ISOTOPE RENOGRAM) periodically, say every 6 months to one year.
Pls contact your doc for followup protocol.