You won't die directly from a heart attack.
Most of the time, it is when the brain suffers oxygen deprivation,
then the brain starts shutting down, followed by organ failures
throughout the body. One hour later probably means she was rushed
to the hospital, and put on emergency life support. But a few
factors, maybe the broken neck, etc etc, (no medical report so
can't tell for sure) lead to her death. Heart attacks can be
overcome by CPR or induced ventilation, but once the brain fails
due to oxygen deprivation, then the damage is irreversible. This
occurs in drowning as well
