Come on, everyone knows that the Ego resides in the Liver.
I think the contextual biases we have towards (ego) and (heart) make them seem mutually exclusive. Words tend to have a central meaning that shifts as their usage and the culture of the people who use them do. Use Ego out of context and the cultural meaning context automatically inserts itself. When someone says ego, the common context has to do with pride and pure self interest. Non-contextualized ego is always suspect. The same process, opposite sense goes for the phrase (comes from the heart). This when said without context is a maxim that is internalized into the cultural lexical ethos to the point of cliche. And without context it will automatically be seen as the exact opposite as ego. As stated above, if abstracted or couched in the proper context they are not necessarily mutually exclusive, but if overheard in a conversation or if they are just thrown out there, they are mutally exclusive by means of the common lexico-cultural understanding of the terms.