a Heart Attack and they will often say the person collapsed, was taken
to a local hospital and after a period of time died WITHOUT REGAINING
CONSCIOUSNESS.

I am strictly a lay person and maybe someone hear can shed some light
of this for me.

Generally, what would cause this type of "post" Heart Attack scenario?
For instance, assuming that the heart stopped for an extended period of
time, would the brain "damage" that likely occured be the reason why
consciousness was never regained?

OR

Are there other medical factors that can cause a Heart Attack patient
to never regain consciousness and pass away after such an event?

Just curious.

Thanks in advance

DAVID