A solution to the Heart problem

There has been a lot of concern on Heart of Tarrasque lately about why the item is not so viable anymore with Skadi being a better substitute nowadays.

I have a small buff suggestion for Heart, giving the user the ability to prepare for the next fight:
Health Regeneration - create buffer HP that increase by 0.1% of max hp per second.

E.g: 3000 HP hero with Health Regen active for 100s will have a 10% buffer HP. Total health: 3300 HP

Incoming hero damage will chew through the buffer HP first. When the whole buffer is gone, it would need time to build up again.
This is just the general idea. the numbers can be tweak for balance, the increased HP can be capped at 1000 or 20%, or it can just be damage block or something. You get the idea. (All this together with the 2% regen)

TLDR; Every second Heart of Tarrrasque beats, the hero overflows with vitality, gaining excess hit points, gearing up the bearer for the next fight.