Antecedents
From left to right: Alfred Blalock, Vivien Thomas, and Helen Taussig.
The first major antecedent is the Blalock-Taussig Shunt.
This was not a mecahnical antecedents so much as a procedure. It was invented by Blalock, Thomas and Taussig (pictured above).
Later, and more importantly, the Hufnagel’s Valve was invented.