4 ms·

I wonder if a pulse is required for any bodily functions we're not aware of, body tends to regulate a few rhythms.

by lugged 5y ago

laser 5y ago
Pulse is central to traditional Indian medicine (Ayurveda) [1]. Will be interesting to see what the science finds, although I wouldn’t personally volunteer to have a pumpless-heart. Sounds likely to have unintended consequences as you suggest. [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4890095/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4890095/
- sokoloff 5y ago
  People aren’t “volunteering” for this in any meaningful way. Their next-best option is pretty terrible.
elric 5y ago
I remember reading, years ago, about someone who was temporarily fitted with a rotary pump. He said his hearing required some adjustment, apparently we sort of constantly hear blood rushing without being aware of it, but that somehow changes when your pulse is gone. How do these pumps affect blood pressure? Does it become constant? That can't be good for the elasticity of arteries & veins?
- ALittleLight 5y ago
  I would hope your blood is still rushing about even with the rotary pump.
  - hhh 5y ago
    It wouldn’t be a heartbeat associated with it, though.
  - elric 5y ago
    It is, but probably at a more constant speed, as opposed to the squeeze-and-relax approach of a normal heart.
- lostlogin 5y ago
  The sensation when your heart stops is sudden and terrible. It feels very quiet and you know for sure that something very bad is imminent. I’m not sure if it comes from the absence of sound or from something else, like the stillness in your chest. The actual stoppages didn’t last that long with me (obviously), but they were very memorable.
  - elric 5y ago
    When I get a couple of ectopics in a row I already feel like I'm about to keel over, I imagine that even a few missed beats would be immediately obvious and dreadful. Blood pressure would start to drop super fast and I suspect your brain won't be too pleased with that. Well done on surviving that!
fho 5y ago
I guess if we find that a pulse is required it will be relatively easy to add a "pressure relieve" valve to the rotary design. Pressure builds up and gets released regularly, just like ye good 'ol pump.
Supermancho 5y ago
Your small vessels are not grown to tolerate a constant pressure. You get aneurysms, clotting is super dangerous because they generally form and sit rather than getting sucked/pushed into the heart to potentially get broken up. Most importantly, forget your potential organ failure you wont notice until there's a lot of damage, and all the numbness you'll get, it's the brain function affects that bother me. Sluggish, memory problems, et al that accompanies tiny thromboses. A rotary pump is an endgame-solution. It keeps you alive, at a cost and you die the end anyway (obviously).
- iancmceachern 5y ago
  Exactly. This is the cause of the phenomenon known as "pump head" that anesthesiologists refer to when patients are on long periods of support on heart lung bypass machines. These machines are peristaltic pumps with a continuous flow. Check out Ventriflo, a new type of pump intended for use in this area that has a biomimetic flow and pressure profile. Www.ventriflo.com
  - jnurmine 5y ago
    There's also Scandinavian Real Heart (https://realheart.se https://realheart.se) from Sweden. They are developing a "total artificial heart" with two chambers and two pumps for a natural blood flow (and pulse). Longterm animal tests are expected to commence after this summer.
    - henearkr 5y ago
      This competition is good. Will push prices down a little bit.

I wonder if a pulse is required for any bodily functions we're not aware of, body tends to regulate a few rhythms.

by lugged 5y ago

I wonder if a pulse is required for any bodily functions we're not aware of, body tends to regulate a few rhythms.

Pulse is central to traditional Indian medicine (Ayurveda) [1]. Will be interesting to see what the science finds, although I wouldn’t personally volunteer to have a pumpless-heart. Sounds likely to have unintended consequences as you suggest. [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4890095/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4890095/

sokoloff 5y ago
People aren’t “volunteering” for this in any meaningful way. Their next-best option is pretty terrible.

elric 5y ago

I remember reading, years ago, about someone who was temporarily fitted with a rotary pump. He said his hearing required some adjustment, apparently we sort of constantly hear blood rushing without being aware of it, but that somehow changes when your pulse is gone. How do these pumps affect blood pressure? Does it become constant? That can't be good for the elasticity of arteries & veins?

ALittleLight 5y ago
I would hope your blood is still rushing about even with the rotary pump.
- hhh 5y ago
  It wouldn’t be a heartbeat associated with it, though.
- elric 5y ago
  It is, but probably at a more constant speed, as opposed to the squeeze-and-relax approach of a normal heart.
lostlogin 5y ago
The sensation when your heart stops is sudden and terrible. It feels very quiet and you know for sure that something very bad is imminent. I’m not sure if it comes from the absence of sound or from something else, like the stillness in your chest. The actual stoppages didn’t last that long with me (obviously), but they were very memorable.
- elric 5y ago
  When I get a couple of ectopics in a row I already feel like I'm about to keel over, I imagine that even a few missed beats would be immediately obvious and dreadful. Blood pressure would start to drop super fast and I suspect your brain won't be too pleased with that. Well done on surviving that!

fho 5y ago

I guess if we find that a pulse is required it will be relatively easy to add a "pressure relieve" valve to the rotary design. Pressure builds up and gets released regularly, just like ye good 'ol pump.

Supermancho 5y ago

Your small vessels are not grown to tolerate a constant pressure. You get aneurysms, clotting is super dangerous because they generally form and sit rather than getting sucked/pushed into the heart to potentially get broken up. Most importantly, forget your potential organ failure you wont notice until there's a lot of damage, and all the numbness you'll get, it's the brain function affects that bother me. Sluggish, memory problems, et al that accompanies tiny thromboses. A rotary pump is an endgame-solution. It keeps you alive, at a cost and you die the end anyway (obviously).

iancmceachern 5y ago
Exactly. This is the cause of the phenomenon known as "pump head" that anesthesiologists refer to when patients are on long periods of support on heart lung bypass machines. These machines are peristaltic pumps with a continuous flow. Check out Ventriflo, a new type of pump intended for use in this area that has a biomimetic flow and pressure profile. Www.ventriflo.com
- jnurmine 5y ago
  There's also Scandinavian Real Heart (https://realheart.se https://realheart.se) from Sweden. They are developing a "total artificial heart" with two chambers and two pumps for a natural blood flow (and pulse). Longterm animal tests are expected to commence after this summer.
  - henearkr 5y ago
    This competition is good. Will push prices down a little bit.