If you take a look at the Wikipedia page for the Quadro line:
It says that the Quadro FX 4500X2 uses the G70GL chip, which is basically the same chip that was used in the 7-series GeForce cards. The first graphics cards to support CUDA were the 8-series cards that used the G80 chip.
Unfortunately, graphics hardware is changing at a phenomenal rate these days (and really has been for the last decade or so); not just performance improvements, but design improvements as well. CUDA requires certain hardware features that the older cards simply don’t have, and so it’s not backwards-compatible with any cards prior to the 8-series. Even if it was, you would probably get very poor performance from it.
If you really want to use CUDA for your video editing studio without spending a lot of money, consider purchasing a GTX260. They can be had for around $150-170, and they also support the latest CUDA features (note: thats GTX, not GTS, which is based on a slightly older chip). And it should have much faster performance than your Quadro.