Cardiac catheter

Forssmann inserted a catheter (a long, thin, flexible rod that was opaque to X rays) into a vein in his own elbow and pushed it along the vein until it reached the heart. The cardiac catheter eventually allowed study and diagnosis of heart conditions without surgery.
 Werner Theodor Otto Forssmann Germany 1929 Cardiac catheter

Forssmann inserted a catheter (a long, thin, flexible rod that was opaque to X rays) into a vein in his own elbow and pushed it along the vein until it reached the heart. The cardiac catheter eventually allowed study and diagnosis of heart conditions without surgery.