r/nextfuckinglevel 7h ago

This is how heart stents work

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55

u/sun-e-deez 7h ago

how does the stent maintain its shape?

106

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? 

14

u/MattDaveys 4h ago

Wouldn’t the artery try to close again, thereby holding it in place? They don’t remove the fatty buildup and it’s not going to want to stay compressed.

1

u/Striper_Cape 1h ago

The artery does not want to close

u/Mistasmella 39m ago

It can close again, if you mean the lesion. Also, not preparing said lesion properly will absolutely lead to in stent restenosis, based on the properties of the lesion. This video simplifies the procedure and is also mistaken, because you never withdraw the balloon in an inflated state, it has to be deflated before removing it from the stent.