How many inputs do you have on the NVR(s)? That's going to be one determining factor here. Getting a relay output for each zone isn't hard. You can use 4204 relay modules to follow a zone. But if you don't have the inputs on the NVR to cover all zones, it's going to be harder.
It's been years since I touched a Vista but it should be on page 35 of the manual under "Output Progammjng"; http://firealarmresources.com/wp-content/uploads/2013/07/Ademco-Vista-128BP-Programming-Manual.pdf You have to create a zone list for each panic I think which is used to trigger the relay when alarm.
Thanks Ethan! This gives me an idea to also use voice module and LEDs to announce where the alarm is.
Remember to use an individual zone trigger - not a list or zone type - then program the relay to - 'close and stay closed' - zone number to start and stop action. Relay should follow zone with fraction of second delay. You will probably need to program the NVR to prerecord a couple of seconds ahead so you don't miss what may have caused the panic! Love those big Vista panels - have done many cool low level integrations with them.