The theory is that sufferers of this condition (that only seems to crop up when people are being assaulted by law enforcement officers) are both “excited” and “delirious.” In some cases, that means their heart rates are increased. In other cases, they may say incoherent things like “I can’t breathe.” In almost every case, the only cure is subduing the person to death, thus ridding them of their excited delirium by eliminating its root cause: being alive while being arrested.
This sounds like something an 18th century doctor would diagnose someone with.