The last line of the story is this: "When the doctors came they said she had died of heart disease-of joy that kills." In what ways is this an ironic statement?

Heart disease is never linked with joy. Still, her death is ironic in that she died of joy at her husband's demise. She won't be able to enjoy life without her husband after all.

She died from disapointment. she wasn happy when she saw her husband she was disapointment