We tried 2 manually revive my grandpa after attack.he died but his heart did beat 4 sometime.if the doctors had come sooner than 30mins, any chance?

Unanswerable: I am very sorry for your loss. There is really no way to know what your grandfather's heart attack really was, what the irregularity of his heart beat was and what caused it. Usually to save someone in this extreme and dangerous situation one needs a defibrillator to shock the heart rhythm back into a normal sinus rhythm and to also be able to provide oxygen. CPR alone is often not enough.