Heating pipe in concrete slab

[Miketinternet]

I have a house in the northeast that was built in 1965 and there is probably 3 or 4 areas where about 6ft of heating pipe is in the slab. I have recently encountered a leak in the concrete and I was wondering if it makes sense to try to fix the one area or replace the whole zone loop ? Some say if the copper was in a sleeve it could last a long time but others say it might be hard to get a clean connection to patch it is so with time and materials it could get expensive patching and there is no guarantee other parts wouldn't fail.

If I replaced the loop I think I could abandon what is there and keep it all out of the concrete since the house layout has changed a bit and with pex it looks easier to route pipe.