From People of the River:
Breathtaker (Ex): The barbarian's blows take the
air from her foes' lungs. While raging, whenever the
barbarian makes a successful melee attack against an
opponent that is holding its breath, in addition to any
other effects caused by that attack, the opponent loses
a number of rounds of breath equal to the barbarian's
Strength modifier.
And Call the Void
Is there anything else that combos with this rage power?
I know its not really optimal to use but I do think it would be kinda fun to work around.
I thought about using it to make the garrote a viable weapon, but due to the ridiculous restriction that the garrote only works on enemies that are unaware of you it doesn't really help.
The Chokehold feat would also work. Maybe Tetori 6/Brutal Pugilist X for a build around this (you'd need the Aasimar trait that lets you be a Neutral Monk for it to work of course).