PCI Stands for Payment Card Industry
PA stands For Patriot Act
I'm not familiar enough with the requirements of PA Compliance (This is the first I've heard of it).
It looks to me like they are trying to accomplish the same thing (Protect against identity theft and stolen credit card info)
it sounds to me that if the site is pci compliant it would also be PA compliant, but I cant say that with 100% certainty.