Werner Theodor Otto Forssmann, a German surgical trainee in 1929, is famous for an experiment he performed on himself.
He proposed a procedure but he was scorned. He believed in the approach so passionately and unable to get permission by the authorities to try it out he performed the procedure on himself.
Without any direction, he put himself under local anesthetic, incised a hole in his arm and pushed a catheter all the way up his limb and shoved it into his heart. He performed the procedure on himself with two feet of cable after which he walked to the X-ray room. He was fired after this so called stunt, but was awarded the 1956 Nobel Prize for Medicine for developing a procedure that allowed for cardiac catheterization.
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