Can you reverse an excommunication? Does excommunication affect your afterlife?

I recently found out that my grandmother was excommunicated for having a (medically necessary) hysterectomy in the 70's. She loved the Catholic Church, but she never returned, and was never the same after this happened. She passed away some time ago, but finding this out has left me with many questions. Does this affect her afterlife? Does the Catholic Church keep a record of excommunications? It bothers me to think that there's some sort of black mark next to her name. If so, can this be reversed posthumously? I feel what happened to her was terrible and unfair, and even though she's gone, I'm just wondering if there is something I can do to right this wrong.