I think, c would be pronounced like "ts", so that would make it something like RITS-ken-a, for all that I know about Czech (which isn't much at all). Unless it's originally c with a v shaped thingy on top, then it would be RICH-ken-a.
However, when I googled that name, nothing Czech came about (other than grammatical forms of the German last name Ricken). So I doubt if that name is Czech at all. Maybe anyone else knows more about this?