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The heart is fundamentally a pump. Are we not able to build a replacement? I understand it’s not simple at all, and that people have tried and failed in the pas

by typest 4y ago

The heart is fundamentally a pump. Are we not able to build a replacement? I understand it’s not simple at all, and that people have tried and failed in the past, but is an artificial heart something that we should be able to build?

davikr 4y ago
It might be a significantly hard problem: for instance, artificial heart valves tend to get infected by bacteria, and if it were the case for a whole artificial heart to get infected, perhaps it could spread and cause damage to the mediastinum (or), maybe, sepsis.
- DoreenMichele 4y ago
  Significantly, the body does a poor job of fighting infection that occurs in artificial heart valves.
  - trasz 4y ago
    Why?
    - DoreenMichele 4y ago
      From what I have read, artificial heart valves, being artificial, are simply not really covered by the immune system. In other words, you get white blood cells to the point of infection because you have blood supply and mechanical parts don't have blood vessels running through them. It's foreign matter, not really part of a living body. Very likely, they probably also attract infections that like eating plastics and such. These are inherently hard for the human body to combat if they get traction, from what I gather. They aren't a normal infection in humans and tend to be deadly when they do take root.
madelyn 4y ago
Artificial hearts already exist. But they usually are only used while waiting for transplants, because they're not as good as the real deal. Hearts are critical infrastructure in the body, with 100% uptime requirements and not-insignificant energy consumption.
seren 4y ago
Carmat has been working on it for a few decades. I believe they have not been approved yet by the FDA but are in the clinical trials phase. https://www.carmatsa.com/en/ https://www.carmatsa.com/en/
nradov 4y ago
Artificial hearts have existed for years but require an external power source to operate the pump. They can generally only be used for a limited time while waiting for a transplant. https://syncardia.com/clinicians/our-products/freedom-portable-driver/ https://syncardia.com/clinicians/our-products/freedom-portab...
tremon 4y ago
IIRC, the problem with conventional mechanical pumps is that they're continuous-flow. Various other systems in the human body rely in the ebb-and-flow of a pumping heart to function correctly, and different activities require different flow speeds. Yes, we can probably engineer a variflow pump as well, and maybe also one that increases and decreases its flow based on hormonal signaling, but it's not as simple as taking your average aquarium pump and connecting it in-place. AFAIK, we have no idea how the heart determines its flow rate.
- usrn 4y ago
  I was under the impression there were implantable impeller style pumps that people used to replace the heart while waiting for a transplant.
  - ceejayoz 4y ago
    They don't replace, they assist. Longest one has lasted is seven years. https://en.wikipedia.org/wiki/Ventricular_assist_device https://en.wikipedia.org/wiki/Ventricular_assist_device

by typest 4y ago

davikr 4y ago

It might be a significantly hard problem: for instance, artificial heart valves tend to get infected by bacteria, and if it were the case for a whole artificial heart to get infected, perhaps it could spread and cause damage to the mediastinum (or), maybe, sepsis.

DoreenMichele 4y ago
Significantly, the body does a poor job of fighting infection that occurs in artificial heart valves.
- trasz 4y ago
  Why?
  - DoreenMichele 4y ago
    From what I have read, artificial heart valves, being artificial, are simply not really covered by the immune system. In other words, you get white blood cells to the point of infection because you have blood supply and mechanical parts don't have blood vessels running through them. It's foreign matter, not really part of a living body. Very likely, they probably also attract infections that like eating plastics and such. These are inherently hard for the human body to combat if they get traction, from what I gather. They aren't a normal infection in humans and tend to be deadly when they do take root.

madelyn 4y ago

Artificial hearts already exist. But they usually are only used while waiting for transplants, because they're not as good as the real deal. Hearts are critical infrastructure in the body, with 100% uptime requirements and not-insignificant energy consumption.

seren 4y ago

Carmat has been working on it for a few decades. I believe they have not been approved yet by the FDA but are in the clinical trials phase. https://www.carmatsa.com/en/ https://www.carmatsa.com/en/

nradov 4y ago

Artificial hearts have existed for years but require an external power source to operate the pump. They can generally only be used for a limited time while waiting for a transplant. https://syncardia.com/clinicians/our-products/freedom-portable-driver/ https://syncardia.com/clinicians/our-products/freedom-portab...

tremon 4y ago

IIRC, the problem with conventional mechanical pumps is that they're continuous-flow. Various other systems in the human body rely in the ebb-and-flow of a pumping heart to function correctly, and different activities require different flow speeds. Yes, we can probably engineer a variflow pump as well, and maybe also one that increases and decreases its flow based on hormonal signaling, but it's not as simple as taking your average aquarium pump and connecting it in-place. AFAIK, we have no idea how the heart determines its flow rate.

usrn 4y ago
I was under the impression there were implantable impeller style pumps that people used to replace the heart while waiting for a transplant.
- ceejayoz 4y ago
  They don't replace, they assist. Longest one has lasted is seven years. https://en.wikipedia.org/wiki/Ventricular_assist_device https://en.wikipedia.org/wiki/Ventricular_assist_device