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In page Coronary catheterization:

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Heart catheterization was first performed in 1929 when the German physician Werner Forssmann inserted a plastic tube in his cubital vein and guided it to the right chamber of the heart. He took an x-ray to prove his success and published it on November 5, 1929, with the title "Über die Sondierung des rechten Herzens" (About probing of the right heart).[citation needed]