World's First Partial Heart Transplant Grows Valves and Arteries (interestingengineering.com) 17
An anonymous reader quotes a report from Interesting Engineering: Marking a significant advancement in medical science, the world's first partial heart transplant has achieved the expected outcome after over a year of research efforts. Carried out by Duke Health, the patient, a young individual, now exhibits functioning valves and arteries that are growing in tandem with the transplant, as initially expected by the medical team. In spring 2022, doctors carried out the procedure on a baby who needed a new heart valve. Before, they used non-living valves, which didn't grow with the child. This meant the child needed frequent replacements, and the surgeries had a 50 percent chance of being deadly. The new procedure avoids these problems, according to the team.
Babies with serious heart valve problems face a tough challenge because there aren't any implants that can grow with them. So, these babies end up needing new implants over and over until they're big enough for an adult-sized valve. It's a problem that doesn't have a solution yet. Duke Health doctors, leading a study published in the Journal of the American Medical Association, discovered that the innovative valve collection method used in the partial heart transplant resulted in two properly functioning valves and arteries that are growing along with the child, resembling natural blood vessels. "This publication is proof that this technology works, this idea works, and can be used to help other children," said Joseph W. Turek, first author of the study and Duke's chief of pediatric cardiac surgery, in a statement. The research also notes that the new procedure requires less immunosuppressant medication, reducing potential long-term side effects.
It also facilitates a "domino transplant" method, where one donor heart benefits multiple patients, potentially doubling the number of hearts available for children with heart disease by utilizing previously unused hearts and valves.
Babies with serious heart valve problems face a tough challenge because there aren't any implants that can grow with them. So, these babies end up needing new implants over and over until they're big enough for an adult-sized valve. It's a problem that doesn't have a solution yet. Duke Health doctors, leading a study published in the Journal of the American Medical Association, discovered that the innovative valve collection method used in the partial heart transplant resulted in two properly functioning valves and arteries that are growing along with the child, resembling natural blood vessels. "This publication is proof that this technology works, this idea works, and can be used to help other children," said Joseph W. Turek, first author of the study and Duke's chief of pediatric cardiac surgery, in a statement. The research also notes that the new procedure requires less immunosuppressant medication, reducing potential long-term side effects.
It also facilitates a "domino transplant" method, where one donor heart benefits multiple patients, potentially doubling the number of hearts available for children with heart disease by utilizing previously unused hearts and valves.
Very cool (Score:4, Informative)
In the next decade or two it ought to be possible to take cells from the patient and grow a new valve in the lab and transplant it back. Then no immunosuppressant meds would be needed. The other alternative is to tolerate the immune system.
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Not news for nerds? People don't give a shit? It's been covered ad nauseum for years?
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Anyone can submit stories. Be the change you want to see in the world. Type up a summary, add some links to major news outlets, and add it to the queue. I'll fucking vote it up myself.
Re:Very cool (Score:4, Interesting)
Unlikely.
It's the same as "the year of the Linux desktop", "the year of successful nuclear fusion", etc. It's always 10 or twenty years away, but not really.
Regenerative, histogenetic, and replacement organ technologies have been played with for many problems in surgery for a very long time, but what we can engineer is always far too simplistic for real nature. ... Which is an interesting conundrum, because as beautiful and awe-inspiring as natural biological embryogenesis and morphgenesis are, they are relatively dumb and dynamically simple processes. Granted, there are countless chemicals, trillions of cells, and many tens of thousands of genes - a complex multi-control system - but once the genes make their products, histo- and organogenesis are free-running self-organizing processes that are largely bug-free (except in the small percentage of congenital anomalies such as truncus arteriosus). Remember, there are no structural genes (discounting major structural polymers, e.g. collagen, fibronectins, cellulose-lignin in plants). There are certainly no blueprint genes, no architecture genes. Genes make enzymes which regulate chemical processes, and for every metabolic process, the "big soup" has promoters, inhibitors, and an allowable state space governed by basic rules of energy and thermodynamics. But, as self-regulating chaotic processes, they almost always converge on the correct anatomy. Strip away the noise of too many chemicals to remember and those goofy haywire drawings of the metabolic pathways, and the many systems are generally easily reduced to some basic control diagrams regulated by just a few key players. Everything in the body, in embryonic growth, is a self-organizing automaton.
For tissues derived from the embryonic mesoderm, which includes the vascular system, mechanical forces are the essential regulators. Mesodermal cells sense, respond, and regulate on tension, compression, and shear. One thing you might have heard of is how astronauts get weak bones in orbit, why they have exercise frames to simulate gravity by axial load on the body. Compressive stress on mesenchyme makes bone. Take compression away, bones weaken.
In reverse, mesenchyme in tension makes tendons. Take the tension away, tendons get mushy and weak. Increase tension, they get progressively stronger and inelastic (which is what you want for tendons). The mitral and tricuspid valves in the heart do not prolapse (reverse direction) because their chordae tendinae prevent that, and those chords depend on tension created during systole. The aortic and pulmonic valves, the ones pertinent to truncus arteriosus, have a different anatomy where shear and tension contribute. It all gets complex, and these comments are made just to give some insight as to how mechanics influence cardiac morphogenesis.
The point is that you cannot just grow biostructures outside their environment, and for the heart, that requires flow, shear, tension, cyclical loading, and neuro-myo-electrical integration. You can simulate or apply these in machine-material and ex vivo systems, but in a living organism where cells and tissues die or fail to organize if conditions are not correct - and keep in mind that it takes days-weeks-months to succeed - then if conditions are wrong, no luck.
Growing pancreatic islet cells ex vivo in culture then injecting them somewhere (for diabetes), that is more realistic - we know how to do simple cell cultures. But a whole organ, especially a highly organized, anatomically complex, mechanically active device like the heart - there is nothing on the horizon how to do that. Current state of the art depends on de-cellularizing organs from donor animals, then using the matrix as a scaffold for ingrowth of host cells. While that "sort of" works to get cells growing, it cannot make a functioning organ. Then, there are problems with inflammation, immunity, then fibrosis which damage whatever you are trying to make.
Truncus repair usual requires something to rec
Re: (Score:3, Interesting)
So, this is a hell of a lot of typing for the context you're posting in, which on its own seems suspicious... like you might have used AI to generate it without putting a lot of thought into it yourself. Luckily, I didn't put a lot of thought into reading it either, but on a skim it does seem to my uneducated eye to make some good points about why this technology can't easily lead to full organ replacement; I'll grant you that much, at least. However, it does also seem like that's not a good enough reason t
Re:Very cool (Score:5, Informative)
First off I was talking about the valve only. I literally wrote valve. While we are probably quite far away from growing a whole heart, growing a valve using the patients own cells is not that far off -- it already is being tested in lambs. References:
https://cse.umn.edu/bme/news/l... [umn.edu]
https://www.science.org/doi/10... [science.org]
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That is not really possible. As the "new grown" thing needs to know into what it is supposed to grow.
That usually means it has to be in the vicinity of the organ it belongs to.
There are exceptions like growing ears or noses on collagen fabric ... but a heart - or anything related to a heart - does not grow out of nothing.
Heart muscle cells are super specialized, and have not much to do with other muscle cells for example.
Sounds like the lead-in to a horror movie (Score:1, Offtopic)
Kevin Jones dies in a tragic motorcycle accident. His heart is donated to a dying young man, Jason James.
Post-surgery, Day 1: The recipient, Jason, is doing well. The transplanted heart parts are functioning as hoped.
Day 14: Jason is progressing remarkably. At the 2-week follow-up, the doctor is surprised to see that it appears the donated sections of the heart have grown to encompass the entire organ.
Day 21: Jason starts seeing, unbidden, memories which are not actually his. When he glances at a mirror, he
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Well, clearly this level of effort would have been better spent somewhere else, but modding it "Offtopic" doesn't seem fair.
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Re: Sounds like the lead-in to a horror movie (Score:2)
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Awful article... (Score:2)
What's particularly impressive about this article and its summary is how far you have to dig to get any useful precis.... and a lot of it is not there at all. For example, "partial heart transplant" - but which bit? Domino... but which part cascades. Less immunosuppressant but why? And most obviously, valves grow with, but what's new about that... does the value come with the heart, or some a different donor, or is part of an adult heart and trimmed down, or another part of the body? I just gave up when