How long does aphasia last after a c.v.a.?

could be permanent: Only time will tell.

This depends on: the structures damaged, the extent to which the individual is left or right handed, the rehab potential at the time of the stroke to some extent, the type of aphasia and clinical course in the first few months. Those with posterior aphasia tend to have coprehension problems that will persist if they do not improve to anomic aphasia within a few months. Those with anterior aphasia do better.