I'm not sure that the past tense works in English here, and you need something like "hereafter" or "from now on" to get across the idea of "passou". Agree with Marian that there's not quite enough context. I'm guessing that the point in question is the bride's new name, but if it's her actual signature that's the important thing, then it would be something like "whose signature will be as follows from now on...".