I suggest the Aegis of the Immortal or Aegis of Immortality get an animation similar to the Radiance inventory Icon.
This is a one of a kind rare item.
Perhaps the core of the item could pulsate in glows like a heart beating and as soon as the Host-hero dies the claw fingers open up,the glow becomes brighter and a drone-sound builds up in a frequency and the icon disappears from the inventory and the sound stops.
All this happening in correlation with the physical resurrection animation of the hero on the battlefield.


There could also be some sort of visual indication for allies which hero is carrying the Aegis,but that is debatable.