personally, I wouldn't worry about the heat bothering the vine itself, or the foliage or flowers, but i'd be a little concerned about keeping the roots cool and hydrated. we have a similar issue on our east facing shop wall. our shop is a dark brown and it gets HOT by 9 am! we mounted a trellis to the wall as suggested above, but we also put 4 inch spacers behind it, to leave a little "breathing room" for the foliage as well. seems to work ok for us. the afternoon shade seems to be a welcome thing on hot days!
