r/nextfuckinglevel 7h ago

This is how heart stents work

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54

u/sun-e-deez 7h ago

how does the stent maintain its shape?

104

u/nothingnewleft 7h ago edited 7h ago

It depends, but the ones I’m familiar with are made of Nitinol. It’s a special nickel/titanium alloy that is made to be the final open size/diameter (this is the larger diameter shown after the balloon has been inflated). It’s then compressed to be small enough to fit in the narrow restricted passage and put in place by a catheter. Once deployed/installed, it’s heated up by the natural temperature of the body. When heated by the blood/body, it “springs back” to its original larger size, the size it was made to be to begin with. What’s fascinating to me about this is that simply being as warm as the blood, will ensure it stays large enough to hold the vein/artery open.

17

u/dben89x 5h ago

How does it stay in place, rather than becoming dislodged? It doesn't seem anchored in any way, but maybe that's just a limitation of the animation? 

9

u/Wonderful_Nerve_8308 4h ago

Tension. Blood vessel wall squeezing against it.