Instead of actively healing through lifesteal, passively healing through just pure raw base health regen. Grasp of the Undying, probably Font of Life, definitely Second Wind, probably Overgrowth, with Health and then whatever for the other two. Secondary runes could be anything but probably Inspiration for biscuits, outside chance of grabbing precision for Triumph. The items, in whatever order, would be Warmogs, Spirit Visage, Adaptive Helm, Righteous Glory, Mikael's Crucible, and Redemption, I think.
Now I haven't actually seen how viable this would be. I'm not quite positive those items are all still actually available for that matter. (Specifically, never heard of Mikael's Crucible as an item before when I've heard of most items in the game. The others I know are in there though.) I'm not sure if some of them have overlapping unique passives. But I mean...in theory, it'd give insane healing.
In practice I am quite sure it could never work.
But hey, aint called troll builds for nuthin'.