This is Ability Power item idea for AP tanks that scales well with Health giving them Edge of Survivability

I think there are more Health options for AD champion and much less for AP Tanks.

Rylai's Crystal Scepter item Rylai's Crystal Scepter may lose its health stats which along with Rod of Ages item Rod of Ages are oriented for AP tanks. Rylai is one of the core items for VladimirSquare Vladimir who would lose quite amount of power and defense

If Scepter is about to become health-less then this item would be good addition as its focused on and scales with health for champions who desire to build more protection and less AP and will be very appealing for VladimirSquare Vladimir SejuaniSquare Sejuani GragasSquare Gragas MaokaiSquare Maokai MalphiteSquare Malphite and other alike