I doubt he will last long, not being in good health lately......but he is sure a tenacious rival of the USA surviving whatever attempts at dislodging him from power. I guess he will be another one that have to be removed by the Grim Reaper himself.
infact, he has taken retirement from active politics....apparently owing to poor health!! although, he has given the authority to his bro Raul, who is a kind of mirror image of Fidel in the way he handles the policy matters.