You don’t have to redo it. You can Delete some of the edges, BUT you should do it this way:

(I don’t have Maya open, so please bare with me. Just use the Help files to see where the things are)

•Find the Select Edge Loop tool
•Select the edges you want to delete
•Then find the Delete Edge command (the reason to do this, is because it deletes the vertices with the edges, making it much better and faster)