The version featuring A is absolutely possible, harmonically speaking; however, it seems much more likely that Chopin forgot to write a 
(as in the previous bar). It is supported by the regular, chromatic bass sequence, contrasting with the chromatic sequence of the topmost R.H. notes (e-f-f
-g); above all, it is supported by the flats in two analogous bars as this theme returns – bar 189 and 372. Considering the above analysis, in the main text we provide the version of the editions, featuring A
.
Compare the passage in the sources»
category imprint: Differences between sources
issues: Omissions to cancel alteration, GE revisions, Errors of A
notation: Pitch