His father, Wakasugi Kaname [ja], served as the Japanese Consul-General in New York City, assisting Ambassador Kichisaburo Nomura.
For leading the Japanese premiere of Penderecki's St. Luke Passion, Wakasugi was awarded the National Arts Festival Prize by the Agency for Cultural Affairs in 1968.
Wakasugi was chosen to be the former's next music director, but the reunification of Germany and the unraveling of the East German theatre system derailed this appointment.
During his tenure there he led the Japanese premiere of Bernd Alois Zimmermann's Die Soldaten a few months before his death.
Aside from performing, Wakasugi also held a professorship at Tokyo National University of the Arts and Toho Gakuen School of Music.