How does a person who dies of a heart attack face the throes of death, and do recitations of the Quran or the fasting of obligatory or voluntary fasts reach the deceased?

Every soul experiences the stupor and intensity of death, as Allah Almighty says: "And the stupor of death will come in truth: this is what you were trying to avoid," and as the Prophet, peace and blessings be upon him, said: "Indeed, death has its stupors." Everyone who dies will experience from it what Allah has decreed for him. Reciting the Quran and dedicating its reward to the deceased, as well as all acts of obedience such as charity and fasting, reach them.