So, assuming that they accept your extenuating circumstances, you will be assessed as a regular candidate. It will be as if you had never re-taken your A-levels in the first place. It goes without saying that you need good predicted grades, a minimum of A*AA for medicine at most universities. In the end, consider if the other aspects of your application: UCAS/BMAT, GCSEs and experience are good enough to form a competitive application for Medicine. In my case, the universities I am applying to (Imperial, UCL and Oxford) have strict cutoffs for the BMAT and do not take into account the A-levels in their initial interview shortlisting.