Most (maybe all) car seats have two methods of attachment - LATCH/LUAS system and just using the seatbelt.
A quick Google search shows me that they use it in Europe too, but call it ISOFIX. As far as I can tell it's just three different names for the same system.
The seat belt method should work regardless of whether the car was made for North America or EU.
Plus, safety standards change all the time. This is just one new standard for them to follow (if it is even different at all).