Yes, the card is quite clear so it will get your point across - whether you understand the reply is another matter!! I doubt the concept is well-known here. One of my friends is vegetarian and she's had numerous problems in Argentina of waiters not grasping the idea that someone doesn't eat meat (shock horror!). In one restaurant, she ordered a dish after being assured that it didn't contain meat only to find that it arrived with a bolognese sauce. The waiter couldn't understand why she was making a fuss about "the little bits of meat in the sauce". So, check and double-check just to make sure.

Order a big steak with either fries, mashed potato or vegetables and you'll be fine. And enjoy the wine too