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Comment by Ensorceled | Hacker News Reader

Reminder: We've been replacing human heart VALVES with pig valves for a long time now. My grandmother lived for almost a decade after her replacement.

https://www.heart-valve-surgery.com/learning/pig-valve-repla...

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I could be wrong but I believe those valves are harvested for their cartilagenous (non-alive) components, their cells stripped, the valves throughly cleaned, and implanted in place. This is not quite the same as implanting an organ with live cells autonomously producing potential antigens on a daily basis

Correct. I'm aiming my comment more at the people asking about the moral ramifications ...

Would artificial valves then not work as well or even better?

Nope, the ball and disc valves were where they started and they had any issues including wear, blood clots and strokes. You could also hear many of them outside the patients body.

The tissue component of bioprosthetic valves is treated ex vivo in such a way as to greatly reduce the immune reactivity. It's practically not a consideration.

Mechanical prosthetic heart values are generally favoured only in older patients where re-operation is not likely to be required. The reason being that bioprosthetic valves have a more limited long-term durability. So why not always use mechanical valves? Their clotting risk is considerably higher and so they require higher intensity anticoagulant therapy - along with all of the attendant complications of that...

Mech valves are actually favored in younger patients, since they don't become calcified, like bioprosthetic valves. However, they do require life long anticoagulation with warfarin, which is dangerous to live with.

Calcification was what happened with my grandmother; due to other ailments and QoL (she was 85) she declined getting a new valve.

Artificial valves last roughly 10 years, typically. Sometimes more. You have to take antibiotics at the slightest sign of any infection, to avoid infectious settlement of the valve.

A family member got a "tissue engineered" valve a few years ago, so the cells (from a human valve, salvaged from the recipient of a heart transplant) were removed, and can be colonized by body cells, very mild to non-existent rejection. This seems to be a permanent solution.

My father got a brand new cow valve a few months ago. He had to choose between that, a pig one and a mechanical one, each one is better for each specific case from what I understand. But yeah, crazy stuff.

I imagine Muslims, Jews, and Hindus would tend to have specific preferences as well.

I'd argue that in islam pretty much all of these restrictions are not applicable when it's for medical reasons. Alcohol is explicitly allowed in such cases (I think it was used to relieve pain in surgeries) , and even pork is okay to eat if you can't find anything else. Another example would be Ramadan fasting, which is not necessary if you are ill or when you are travelin. Overall, almost any restriction in islam is very flexible when it's a matter of life or death, or if it's a medical necessity/recommendation. So, a pig valve is arguably not any different from a cow valve when it's so clearly not for regular consumption.

You can rationalize all you want, but you can't reason religious people out of things they didn't reason themselves into. If these people can be convinced that they shouldn't be doing thing XYZ on the order of an omnipotent being that nobody has ever seen, chances seem to be even between them accepting exceptions from this order and them rejecting these exceptions. After all, you see other people rejecting/ignoring other parts of their own religion all the time.

> reason religious people out of things they didn't reason themselves into.

Please don't presume things about religious people, especially since you're not one yourself.

That is not a presumption -- it's a statement of fact.

It's not rationalization, I know some religions have a pretty rigid structure that you need to rationalize your way around when it comes to medical exceptions to religious rules but... Islam is not one of them. Maybe some folk belief might be a source of hesitation in this case but in islam the jurisprudence is very clear and no scholar would really argue otherwise. Just to give an example, even ISIS allowed alcohol to be used for medical reasons if prescribed by a doctor! I'm Muslim and have a pretty good grasp of the beliefs of the different islamic branches/sects/schools and I've rarely came across an example of restrictions not being waived for medical reasons, though it's very possible I've missed some examples.

But you're still arguing about perfectly following a set of arbitrary rules. The very fact that they're arbitrary means you'll get people who'll make up arbitrary religious rules for themselves (and they will perfectly follow those) and the "beliefs of the different islamic branches/sects/schools" will be no more relevant for the beliefs of an individual than a codified national language is for some people's idiolects.

They are not arbitrary though. Historic, perhaps. E.g. pork was disallowed as far as I know due to the spread of diseases from bad conservation techniques at the time.

But that's one of the differences between faith and knowledge, namely justification. You'd be correct to claim that it's non-arbitrary if you happen to know that this justification was how it was arrived at. Randomly arriving even at a correct belief without justification would not AFAIK constitute knowledge.

IMHO this is human arrogance. It's the belief that as a human you are able to know and justify anything and everything with science and rationale, which is mostly wrong if you look at history.

It's not unknown for religions to explicitly set the preservation of life above other rules, eg in Judaism:

https://en.wikipedia.org/wiki/Pikuach_nefesh

Is it allowed for all medical reasons, or if there's a genuine alternative would Islam dictate going for that instead?

I can't say for sure, but going from my interpretation of what seems to be the (sunni) scholarly consensus, it really shouldn't matter. Pork is not allowed to be eaten for a few reasons, none of them are relevant for cardiac valves especially considering you don't ever "consume" the pork. Pork is only allowed if you don't have another alternative when it comes to feeding yourself,but since I don't think it's restricted at all for most other uses, there's no need to even have to chose an alternative if possible. Though there is definitely a cultural repulsion towards anything related to Pork in Islamic countries so I'd definitely expect alternatives to be more popular based on that repulsion/taboo even if it's not haram

I wish you were right. We got scolded for using donors’ breast milk for our newborn because donors might have eaten pork. SMH.

EDIT: I understand where you are coming from. I follow the most liberal and rational interpretation of Islam. But feel like we are very small minority.

That is very weird. Was it from the family or from an imam? I know breast milk has a few rules around it in islam, but it mostly boils down to sharing breast milk creating a form kinship between the babies sharing the milk. As in, you become in a way sister/brother with the other baby.

But I agree that many Muslims have a...lot of folk beliefs and take a lot of mental shortcuts that lead to reductive interpretations of the religion. In those cases, bringing up good Islamic jurisprudence usually works.

It was family elders. They are pretty serious about religion, attend Islamic lectures etc. And they were mostly concerned about pork consumption of donors. No one mentioned anything about forming milk kinship.

> family elders

With all due respect, the worst people you can ask for religious advice would be family elder, imams in local mosques. In that order. Find someone who actually studied the religion not just someone who memorized a book.

Vegans, too!

You'd think so, but at least for Jews there is no restriction on this. The rule about Kosher is specifically about eating it.

I'm not sure why you are being downvoted. I know several Jews that I very much suspect would have a visceral reaction and not want the pig-based option, regardless of whether that's really what Jewish law requires.

I'll speak to Jews. There is no such restriction or even preference.

Not only is this not a problem, Israel does a lot of research on creating pigs that are compatible with humans. Jews have no issue with pig heart valves. In general, the idea is that in Judaism human life is critical. You do what it takes to save lives. Only after that do the rules matter.

You can live indefinitely with animal valves though they may need to be replaced every 15 years or so. It’a a fairly straightforward minimally invasive procedure though.

Wait, what?

Are you saying that replacing a valve in your heart is "a fairly straightforward minimally invasive procedure"?

Pretty much standard procedure nowadays. The search term for this is TAVI (Transcatether Aortic Valve Implantation)

Huh. This is pretty cool: https://www.mayoclinic.org/tests-procedures/transcatheter-ao...

They say that you might stay a night in the ICU, or perhaps a couple, but that's way way better than the week+ and months of recovery.

Well, I learn something new everyday - thanks!

Yes, you can probably be in and out same day or maybe the next day.

Reading between the lines, https://www.mayoclinic.org/tests-procedures/transcatheter-ao... says you'll probably be there overnight.

I, for one, would be really really nervous about having a major operation on a critical-for-my-life organ and then going home. I would definitely want some close observation even if it's 'just' for 12-24 hours.

Well if it fails you probably die suddenly.

According to another article, that was also true of this patient.

May I ask how much did it cost and did insurance cover it?

A surgical aortic valve replacement (SAVR) for example will cost ~50K I believe? It will be covered by insurance if it is necessary.

There are also less invasive forms of valve replacement (transcatheter / percutaneous) which involve collapsing a synthetic valve around a balloon at the end of a catheter, inserting the assembly into a femoral artery, guiding the valve into the heart and into the open damaged valve, and then inflating the balloon and deploying the new valve inside of the damaged old valve. In SAVR the old valve is removed and the new one is sewn in. In transcatheter aortic valve replacement (TAVR), the old valve is held open by the new valve.

Is anyone having an aortic valve replacement that isn’t necessary?!

Er, no, although that was a funny way for the parent to phrase it.

It might be more accurate to phrase it as "depending on your insurance, your insurance may pay for it if it's covered AND you _meet_the_criteria_ for the procedure."

For example: You may run into a situation where your doctor says "You know, it would be good to replace this now" and the insurance company says "Thank you for your professional opinion; our table says that we're not replacing it until criteria X is also satisfied"

Not OP, but my dad was offered either a mechanical or pig valve when he had a bypass surgery done. Both were covered by insurance, I don't know which cost more, but he hit his deductible either way.

My grandmother was Canadian, as am I ... so nary a clue about the cost.

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