"Chikao Ōtsuka died from ischemic heart failure at age 85 on January 15th, 2015" from his wikipedia's page http://en.wikipedia.org/wiki/Chikao_%C5%8Ctsuka
Oh wow, this guy did alot of stuff. There's alot of videos on youtube commemorating him. I found a couple of interviews of him and his son (apparently he was the Japanese Big Boss, as well).