@TayZonday Would you consider making some or all of your subscriptions public? Like me you seem to love learning since we share a few science- related channels in common. It would satisfy my curiosity to see what else is out there that you enjoy 😄
in doctor who they solve the “can’t fit two hearts with the lungs right there” issue by time lords having a completely different respiratory system - they have pulmonary tubes like the lymphatic system (which also makes them float like a raft apparently). their hearts also beat in a 1-2-3-4 pattern, presumably one heart then the other, so their organs probably rely on constant flow as opposed to a pausing one like ours. the doctor does canonically have massively high blood pressure compared to humans - in an ep with thirteen a totally-not-space-amazon ai tries to sell her blood pressure meds lmao
What an interesting idea to explore: Is the design we have the best design we COULD have? One thing different would affect so many systems in the body.
Well I'm pretty sure there's an nerve or something wrapped around a part of our heart that is kinda dumb "design" wise so we're definitely not the best we could be.
no. we are not designed the best we can be. we are built to be barely good enough. our purpose biologically is to survive to reproductive age and reproduce. as long as we can accomplish that, according to natural selection we're golden. this good enough principle applies to everything. like no our knee joints suck, but they're good enough. yes our wrists are made of 15 bones that can shatter at any moment or get dislocated, but it gets the job done. natural selection is all about the maximum result with the minimum effort.
@@looksirdroids9134 mate. No one was saying this? "Design" might not be the best word but it's used a lot. Cool it. No one, even other Atheist, like a hateful Atheist. You just give everyone a bad name.
Or, both hearts could be small. Tow small hearts would be the same as the one heart we now have, but like you said, one heart would take care of certain systems while the other heart took care of the rest. Great video, thanks!
It could just be a backup heart and you could slightly decrease the size of the normal heart, lungs and other organs to give it room. As a backup heart, its design would be to just barely aid the main heart until the main heart experiences some sort of trauma that harms or even kills it. Then the backup hearts system and even the cell in it would be designed to compensate to the degree that the main heart was harmed. So if the main heart lost 10% function, the backup heart (let's say it is normally only at 10% function) would double in effective volume of pumping to compensate. There could be tricks to make this happen rapidly but not immediately, and if done too rapidly it could obviously kill someone so there would still be a moment whether that is hours, days or weeks of weakness after a heart attack but the backup heart could eventually take over some or all of the duties while a special system designed to repair heart tissue could fix the main heart slowly over the years (which would now act as the new backup heart, assuming it could repair itself soon enough). People claim brain and heart tissue does not regenerate but that's actually untrue, it just usually doesn't do so rapidly enough to make a huge difference. So, having a backup heart would be a good idea *if* the rest of the body could handle it and if natural or artificial means could be designed (through medicine or evolution) to create a system or cellular process that increasing the heart's ability to regrow and heal but *only* when needed (otherwise there would be overgrowth or cancer). If some animals have multiple stomachs or no stomach, there is no reason to think humans couldn't adapt to house two hearts. The question is how and would it takes day to years with medical intervention, or hundreds to millions of years with bioengineering and evolution? And, then, was it worth the effort and adaptations? What is the cost even if any ideal means of doing this is found? Is it better than letting the person die or giving them a heart transplant or artificial heart instead?
Your videos are so interesting! Our bodies are so incredible, complex, and beautiful it’s so fascinating to have it broken down into short explanations with visuals (I’m 💯 a visual learner so I appreciate how much time you put into your videos SO much!) thank you for all the hard work you put into doing this!
I don't know enough about the topic to be able to tell you whether you missed anything or not, but I definitely do want to see more videos like this! Further exploration of the "what ifs" of the human body would be fascinating.
Thank you! This is perfect. I'm working on a sci fi story where my alien character has two hearts. This has helped answer some of my background questions.
This makes me wonder if there has ever been a set of siamese twins with two hearts functioning in one system. If so I would like to see a video about it.
I wanted to make a comment on the total knee replacement. I very much enjoyed your lecture on this subject. I had a total knee replacement in Aug 2021 Had a excellent surgeon. Almost 2 years later I still have pain,not constant,but makes me wonder why I did,I trade-in one pain for a different one. I belived my age had something to do with it,I have friends that has had this done and are doing great.I will not have the left knee done. I had the What want to call the compressor on my thigh. In my case I had back surgery so they couldn't Numb me in the back. After all this time and physical therapy, that Muscle gets angry. I wish everyone that is going to have this surgery should listen to your lecture. I learned a lot. Thank you.
I feel like the initial questions were perfect for engineers, preferrably hydraulics. If there was constant pressure and flow, would you need the backflow preventing flaps? Could you make a video about how the donated bodies are preserved so they don't rot and go bad and you can present them in educational situations repeatedly?
He already did.. he spoke about how they are time donated and must retain every crumb removed. How they apply some kind of fluid and keep the corpses from rotting. He wears cloves all the time.
i have been working on potential layouts, one of which has several micro hearts catering to various sections of the body.. so even if one fails, the human doesnt have to die
Great thought experiment! The brain maybe with it's own "remote backup pump" like large aircraft have for hydraulic systems if an engine driven pump fails or needs more pressure (usually electric). Fun stuff! Thanks!
Hey, did you think for a moment all other implications of introducing the other heart? How many songs would have to be rewritten, how many phrases would no longer make sense... Owner of a lonely heart... (a heart would never be lonely!), my hearts will go on, from the bottom of my left heart, etc.
Instead of having one failure point, you will have two failure points. One heart gets suffocated without the other and if the other fails, then you experience loss of consciousness and possibly brain death.
Yeah, unless they're redundant, it seems like it would be a major disadvantage to have two hearts. It's amazing that the heart manages to do what it does for so long, but it is the most likely organ to fail and cause death. With two of them serving different but mandatory functions, I can only imagine life expectancies dropping by a decade or two.
I always wondered a similar question involving a split left and right heart being that the sides technically don’t have connections except for the veins and arteries briinging the blood back, only disadvantage is that the atrium and ventricles would need separate electrical signals to function and i also see no benefit. I thought it was funny and amazing that you literally made a completely new human Essentially and worked out how the vasculature would have to respond!
I actually heard a story of a guy with two hearts, I even know the guy even though I didn't hear it from him directly. Of course I haven't seen any x-rays and he's still alive to my knowledge. From what I heard, his body adjusted well enough as he grew, he's generally fine UNTIL the two hearts are out of sync. When they aren't which happens occasionally, he's only capable of lying down and trying not to die until they sync again. And that's all I know.
@@austinroberts8366 I know the guy personally and heard about it from our mutual friend with whom he was way closer. Of course the friend can lie, doesn't really have reason to.
What about a bypass turbo charger. It's like a small pony heart either before or after the main heart. In bypass mode it just allows the blood to flow through but when needed it could help with small extra pumps when the body needs a little extra volume without a lot of extra pressure? And/or it could send an extra squirt or two of blood back through the lungs for a double shot of oxygen..... When not needed it relaxes and opens up to let the main heart do all the work. Maybe it could open and close a little like a pressure regulator when needed.
I think that, to make the body more efficient, we wouldn't need to have another heart, but a third circuit and set of chambers in the one we already have. The circuits, instead of being the general and the pulmonary, would be the primary (sending nutrients and oxigen from the heart to other organs and collecting CO² and waste), the cleanser (going through the intestines, liver and kidneys to collect nutrients and get rid of the waste) and the pulmonary (getting rid of the CO² and collecting oxygen). That way organs would be more efficient. For example, now when the kidneys process the blood, the clean and freshly filtered stream gets mixed with the waste-filled blood coming from other parts of the body, but with this system that wouldn't happen.
Isn't the cleanser just doing what the lymphatic system does right now? Like, partly atleast I guess? (I've not learnt much about it so I may be wrong)
@@annanyaverma1810 Partly yes, and more efficiently, but even then the lymphatic would still be necessary, because, even without taking into account the immune system, the excess fluid left by the blood still needs to be drained. Good point though, I didn't think of that.
Can you make a video about blood groups ? Like what is the differences between each group , what determine our blood group. Why is there multiple blood groups. Etc.....
If you ever come back to check the comments, I want to ask a question what if you’re a rib that was a surgery to make him space better why you made more space for the heart could you have two of the same size heart and how would you add a new vascularto your body is it possible to add more veins?
I feel like both hearts would end up being smaller and weaker than a single heart. Blood pressure would probably be the same or better than most with a single heart. If you had a heart attack in one heart you might also have a much higher chance of surviving.
Two hearts in parallel, echa one connected to the same arteries/veins as standard. The difference would be the “rest period” at the end of each heart beating cycle. Both hearts would need to be completely out of phase. In short, one heart goes through its entire cycle with a long “standby” period while the other heart beats. If one fails, the other heart would need to readjust by decreasing the wait period between beating cycles. Hard to explain in words 🤨 without getting too technical.
There's a form of heart transplant surgery, the heterotopic/piggyback heart transplant that attaches the healthy donor heart to the vessels, without removing the patient's. It's usually done when removing the original heart isn't a good idea, or very helpful. But also means that at worst, you could have a human with two hearts, but no other differences in anatomy, and they'd be fine.
Imo the point of two hearts is to have a backup, like almost everything else in the body, if you had a system that depended on two hearts with distinct jobs what would happen if one fails? idk about you but i would like to have less critical failure points in my plumbing. So if either ones failure is going to be game over might as well just have one bigger heart... anyway two hearts in parallel with some cutoff system for blood loss and asynchronous pumping, maybe even some long rest periods for each one in the night or something to repair damage idk. ps: If we are just redesigning the body here i would like if possible avian respiratory system i hear they are more efficient, maybe even get so extra space for another heart lol.
You only gave the case of hearts operating in parallel (or independently). A better solution would be having the hearts connected in serial. If one failed, blood would just flow passively through it. The other may have to take up the slack to maintain pressure. With two in series, each would operate at half power and with less wear and tear, but with a backup already on line to compensate if one fails. I doubt changes to pulse rate would be too much of an issue, as continuous flow artificial hearts (ie, no pulse) are already use.
Very interesting. One thought that occurred to me was what if one was merely a much smaller auxiliary heart that ensured flow to the brain. Imagine a system where if we were injured, our bodies would automatically reroute in order to ensure adequate blood flow to the moat necessary for life organs. I still think the most useful adaptation humans could want would be bi-hemispheric sleep, as some birds have. One side of the brain sleeps while the other maintains awake functions.
We have in fact two hearts combined into one. One is for our gas exchange, the other one is for the rest. So, in this particular point, we are considerably different from fishes (to which we have most of our design in common). Fishes have really just one heart which drives a simple linear arrangement of respiration and body nutrient supply. We have body overtemperature to environment. So we need more degree of freedom for the regulation of heat exchange and for the respiration of gaseous oxygen and carbon dioxide.
What happens if one heart fails? Consider if the heart suppling the brain was working normally while the heart supplying the rest of the body failed completely. You would be aware of your body dying. I think about patients I have cared for who had a necrosed leg due to vascular disease. They were in excruciating pain before amputation. Now consider the entire body undergoing necrosis. Wouldnt live long, but it would be horrible.
Multiple pumps in line are not that unusual for industrial applications. If the second heart were located in the lower abdominal cavity it could be in-line and pump blood from the legs up into the torso. The primary heart in the chest cavity would pump just as it does in the current layout, except the pressure would not drop quite as much between beats. Instead of 120 over 80 (effectively 100) and it could be at 110 over 90 (still the same average effective pressure). The difference between low and high is not a requirement of the pump, it is a result of the flow rate combined with the pressure. In the case of a biologic system, as long as the flowrate and pressure supplies the right amount of blood cells to the lungs, allows sufficient time to dump the CO2 and load them up with O, the rest of the system couldn't care less if there's 1 pump (heart) or a series of hearts (pumps). But the lower heart (pump) has to be coordinated to work in tandem with the upper heart. Sure the brain could deal with this , but some brain cells currently tasked with other chores would have to be utilized. In the end possibly more brainpower going toward running the body and less toward intellectual function. (There's only so much space in the brain cavity).
Can you do a video on nephroptosis? My grandson recently had kidney surgery, and they found that one kidney was so out-of-place, his surgeon took photos and is publishing an article on it (Vanderbilt Children’s). He also had an artery wrapped around his kidney, which was the original reason for the surgery. It wasn’t til they opened him up that they found his kidney was sideways and way out of place
Don't we already have 2 hearts, one to pump the blood to the lungs and one to pump the blood to the rest of the body? If I were to add a third heart, I'd put it at a distance along the artery system to give the blood an extra push where it is needed (e.g. to improve leg performance then put it at the base of the spine to provide extra flow to the legs), this would also allow for the current heart to be smaller as it wouldn't need to maintain blood pressure through the whole system.
There should be a video like this talking about how Siamese Twins are wired inside. How does the body know how to connect them since the body is already set up for a single person.
If you could get the "downstream heart" to pump according to what it was sent by the "upstream heart" ("wired in series") that might be better? (Synch by pulse, meaning the upstream heart is in charge). The idea would be that under lighter loads, both would have less work to do, but if necessary they could do "double" the work - up to the usual "speed limit" you have on a heart. If both remained full size, if one failed, you'd need a failure mode where it went over to "free flow", and the other could be "the heart", as we know it (just working a bit harder because of the extra heart in the path). A use case for "wiring in parallel" might be to have one heart pumping for our gills, and the other for the lungs. But then we need to first get the gills. Hmm ... you could have bilateral hearts for everything downstream of the head? So if one fails, you lose half your body instead of all of it? I need to get the plumber around next week, so I could ask him.
I've just had an idea how one could survive with one real, and one artificial heart that might not be complete junk. If you had one heart inside of another, the outer heart could help out the inner heart. That's the essence of it. Instead of thinking in terms of replacing a heart that's not working properly by removing it, and substituting it with something that gets hit by things like "tissue rejection" (one of the scraps of information I've heard about these), wrap it up with [waves hands a bit] that helps it do its job. "Use the old piping", though.
What about two separate circulatory systems that do different things, like circulatory system versus lymphatic system? One could specialize in nutrition delivery and waste collection while the other in circulating oxygen and carbon-dioxide.
Such an incredible idea! I would love to see one heart per lung. Man you really have my brain working! I love the idea of the hearts taking turns!! Seriously the best videos on the internet ❤❤❤❤❤😍😍😍
If a person has 2 hearts and has Congestive Heart Failure, would both hearts be affected? The reason I ask is that my husband passed away from CHF. His heart was enlarged twice and his Ejection Fraction was only at 12%. He had a heart cath and it showed that he had no Coronary Artery Disease. He also had a pace maker. His kidneys took a hit because his heart was enlarged and was on dialysis the last few months of his life. His kidneys stopped functioning altogether and became necrotic. He left the Cleveland Clinic after 7 weeks and was sent home with a dobutamine pump. He was on the highest dose, which I think is 5mg/ml. Even with the dobutamine his BP stayed at about 60/42. I would be really interested to know how that would've affected him.
It would be a great video if you would like to touch the topic "what happenes to the body organs when it catch fire? living body in case of fire outbreak accident or dead body when it is on funeral pyre. I have seen often skull explodes when dead body is cremated on pyre. May be because of the pressure of fluid around the brain. And somany other facts can be revealed in the video.
Chris Isaak sung it: "One heart can never win, it takes two hearts. Two hearts, two hearts just to hold love Two hearts, two hearts just to hold your lo-o-o-o-o-ve Your lo-o-o-o-o-ve" (From True Romance soundtrack. Script by Tarantino. Love and bullets.)
Hearts in series, alternating shifts, assume if we're allowing for duplicate vessels we could also allow for the timing to have evolved in a reasonable way
I highly recommend looking into the anatomy of a Space Marine from the Warhammer 40k universe, they sort of go into detail of how they make space marines, and most importantly, they have two hearts
It would be interesting if, over a person's lifespan, the hearts changed in dominance. When you're born, your left heart does most of the work, while your smaller right heart does less. As your dominant heart ages, your smaller heart grows in pace, until the functionality swap and the left heart is replaced by the right, with freshly grown muscle ready to chug along for the rest of your life. It could actually reduce wear on both, if we want to maintain a normal blood pressure, the dominant heart could always run a with a bit less force, and the small would make up the difference.
As someone who is a maintenance electrician 8n the water industry my immediate thought was why not three. Duty, assist and standby is standard pump practice on my sites. They would be in line and cycle their tasks. Duty would run constantly then instead of increasing the BPM during exercise, assist would kick in with standby there should there be an issue with the other two.
We do kind of have two hearts, or at least two sets of pumping chambers each serving separate circulations, the pulmonary circulation to reoxygenate the blood and the circulation to the rest of the body to deliver the oxygenated blood to cells. Our heart consists of both these pumps and links the two components of the circulatory system. I also thought of star trek, and klingons, the warrior species that have two hearts that are redundant to the degree if one is injured the other still keeps you alive.
Some would argue humans already have two hearts: one for the systemic circulation and one for the pulmonary circulation. In other words, the argument is that the left side of the heart and the right side of the heart are two different hearts. But if a whole separate new heart were added increasing the amount of blood flow, a new question arises of how this would increase lymph flow? How would the lymphatic system handle potential increases in drainage from the blood if blood flow increases from having two heart?
one way I’m thinking about it is instead of an entirely different heart, the main heart we have is cut in half into two smaller two chambers hearts, one for de oxygenated blood and the other for oxygenated blood. Idk just my thoughts
Octopi have three hearts, I believe the central one just handles the circulation to the gills, and the outer two distribute oxygenated blood (each handling one side of the body). The hearts are all two chamber hearts, unlike ours. Really that highlights the obvious use for a second heart - pump the returning blood to the lungs more actively. I think you could get away with a smaller two chamber heart here - anything at all is enhancing the return circulation anyways. It seems to me the obvious reason to want this is that you're supposed to be spending time in orbit and your existing circulatory system relies too much on gravity for return from the head, and secondary pumping from muscles you just don't use as much in your limbs. Replace these (very cleverly optimized for life on Earth) systems with the active "return heart" to keep the blood circulating properly, instead of pooling in the head and creating increased blood pressure behind the eyes like it currently does in humans. Your main heart can probably be reduced in size anyways if you're in orbit as you won't be fighting gravity, which gives you more room for your "return heart".
About the positioning. It just came to my mind that maybe the retroperitoneal space could have some sort of mediastinum in it. After all, we can live with a small amount of small intestines missing and would also have the proximity, and maybe the connection, to the abdominal aortic artery and lower vena cava. Geez it feels like I'm getting ready to build Frankenstein monster haha.
I felt like answering the questions. Naturally, the hearts would be of different sizes! Maybe the purpose of the smaller one would be to help blood keep the momentum when going through it or accelerate the blood flow, so the smaller pumps seconds AFTER the big one. And the hearts would be like kidneys: you can still live having the only one, but god forbid you being left with the smaller one. That would be a ban for any hard exercise or activity. Also, less important part, I'd put them one under another. ....aaand then I've watched the video. :D
Run it like a twin turbo. One is in idle and kicks in when you are doing high exertion activities. This should make us much faster beings also. Having higher blood flow to carry oxygen around the body. Of course our bodies would be adapted to this having larger veins and arteries to carry the volume of blood etc.
I heard that one patient got second temporary heart (artificial) for several months prior to an operation to provide some "vacation" time to original heart. Look at Tesla semi - one engine works all the time, the second - only during acceleration. Chest and shoulders could simply be wider.
Maybe the best place would be have the larger heart where it is and replace "useless" organs like the appendix with the smart heart (have the larger heart work with the upper body while the smaller heart for the lower body) and reroute couple medium vessels from the larger heart to the smaller vessels from the smaller heart so the legs can get enough blood/oxygen
Probably not related… I had WPW (Wolff Parkinson White) Syndrome. It’s you’re born with a 3rd, extra electrical pathway in your heart, instead of 2 like normal. I was born with it, but it stays dormant until you’re about age 8 and your heart randomly has episodes of rapid heartbeat. Once mine was about 245 BPM. Thankfully my cardiologist decided to do an oblation to zap away the extra pathway when i was 10 years old. That doctor has passed now due to old age but that doctor saved my life. I’m now 26 years old and completely healthy with no signs of it coming back.. I only speak of this because most people don’t know about it.
Octopi have one main, systemic heart that pumps blood to the whole of its body. But they also have two additional hearts, responsible for pumping blood over each of its gills.
If they could beat in a semi-synchronos fashion to maintain a more constant blood pressure, the overall workload would be decreased while perfusion would remain. I wonder if there's a reason for the fluctuation of pressure we're not even aware of 🤔
Space marines from the warhammer 40k universe have two hearts though they are genetically modified 8 foot tall superhumans. Why did i say all of this i don’t know but hey the more you know
I think you missed ANF hormone which is released by the heart which (to some extend) control the blood pressure, blood volume and functioning of kidneys with two hearts it would be much more complex. lower blood pressure in one heart (due to any reason) might trigger the secretion of ANF which will increase blood pressure (for both the hearts) which might lead to problems. This is based on my understanding on ANF hormone and on the model of two hearts you proposed, do let me know if I am wrong or if I understood it wrong.
Pregnancy would be a risky business with two hearts.. (Along with the foetal circulatory configurations.) We already know that blood volume drastically increases alongside your heart's workload... Yikes.. All I can think of is? Massive amounts of high Pressure for mum... and a bumpy state of survival for bub!
Lots of fish have two hearts, octopus & squid have 3! And some people having a heart transplant leave the original heart in & graft on the new one, so yes two hearts in 1 human body.
Really glad for for your content, using the correct anatomically names and easy to digest them to who doesn't know the terms. I wish this channel existed when I had anatomy. I didn't understand anything event though we had lectures, labs, and gray's and netters, haha. Only thing that worked was flash the cards :P
I am absolutely fascinated with this content! This video was good, however, I felt as though you there could have been mention of the different adaptations that would need to happen to facilitate two hearts.
Thanks Reon! I do want to point out that it’s mentioned a few times in the video that the organs and tissues would have to adapt to the new heart, circulatory pattern, etc. It was decided to keep that brief due to time constraints, but the need for adaptation was indeed mentioned. All the best!
I think I saw in some document how body doesn't function well on steady blood flow. So when hooked up to a machine that circulates blood the body slowly dies.
Excellent hypothetical question & breakdown of reasoning Yes the scientific thinking this raises is great on a meta level Oh & is there a time when this might happen in reality ? There looks to be a cardiomyopathy connection where a surgeon may splice in an additional heart in parallel (internet & likely unreliable source here)
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Why not more direct air ways to lungs
@@osmosisjones4912?
What about "Siamese twins" split at the hips with two separate bodies and two heads but with one set of legs?
Thanks you for sharing with me 💯 💙 💚 😊 ☺ 😘 💯
Wouldnt the last option stop working if only one heart is dying, therefore kinda defeating the purpose of having two hearts?
And in another timeline, James from the Human Biology Center is speculating how everything would work if we only had one heart
A story worthy of a "Fringe" episode
that's an interesting concept.
According to Star Trek, Klingons have eight heart chambers.
Chocolate rain.....
That explains the emotional outbursts...
@TayZonday Would you consider making some or all of your subscriptions public? Like me you seem to love learning since we share a few science- related channels in common. It would satisfy my curiosity to see what else is out there that you enjoy 😄
😂😂😂
They have twice as many ribs as well.
in doctor who they solve the “can’t fit two hearts with the lungs right there” issue by time lords having a completely different respiratory system - they have pulmonary tubes like the lymphatic system (which also makes them float like a raft apparently). their hearts also beat in a 1-2-3-4 pattern, presumably one heart then the other, so their organs probably rely on constant flow as opposed to a pausing one like ours. the doctor does canonically have massively high blood pressure compared to humans - in an ep with thirteen a totally-not-space-amazon ai tries to sell her blood pressure meds lmao
I like Doctor Who also. I am looking forward to new stuff.
What an interesting idea to explore: Is the design we have the best design we COULD have? One thing different would affect so many systems in the body.
My thoughts exactly! Glad you enjoyed it!
Well I'm pretty sure there's an nerve or something wrapped around a part of our heart that is kinda dumb "design" wise so we're definitely not the best we could be.
no. we are not designed the best we can be.
we are built to be barely good enough. our purpose biologically is to survive to reproductive age and reproduce. as long as we can accomplish that, according to natural selection we're golden.
this good enough principle applies to everything. like no our knee joints suck, but they're good enough. yes our wrists are made of 15 bones that can shatter at any moment or get dislocated, but it gets the job done.
natural selection is all about the maximum result with the minimum effort.
It isn't a design, it's evolution. Creationism is a myth and anyone who believes in it is a moron.
@@looksirdroids9134 mate. No one was saying this? "Design" might not be the best word but it's used a lot. Cool it. No one, even other Atheist, like a hateful Atheist. You just give everyone a bad name.
Or, both hearts could be small. Tow small hearts would be the same as the one heart we now have, but like you said, one heart would take care of certain systems while the other heart took care of the rest. Great video, thanks!
In Doctor Who the Doctor had a 4 beats per minute hearts rate! ❤❤💕
😳
Yep same 😀
It could just be a backup heart and you could slightly decrease the size of the normal heart, lungs and other organs to give it room. As a backup heart, its design would be to just barely aid the main heart until the main heart experiences some sort of trauma that harms or even kills it. Then the backup hearts system and even the cell in it would be designed to compensate to the degree that the main heart was harmed. So if the main heart lost 10% function, the backup heart (let's say it is normally only at 10% function) would double in effective volume of pumping to compensate. There could be tricks to make this happen rapidly but not immediately, and if done too rapidly it could obviously kill someone so there would still be a moment whether that is hours, days or weeks of weakness after a heart attack but the backup heart could eventually take over some or all of the duties while a special system designed to repair heart tissue could fix the main heart slowly over the years (which would now act as the new backup heart, assuming it could repair itself soon enough). People claim brain and heart tissue does not regenerate but that's actually untrue, it just usually doesn't do so rapidly enough to make a huge difference. So, having a backup heart would be a good idea *if* the rest of the body could handle it and if natural or artificial means could be designed (through medicine or evolution) to create a system or cellular process that increasing the heart's ability to regrow and heal but *only* when needed (otherwise there would be overgrowth or cancer). If some animals have multiple stomachs or no stomach, there is no reason to think humans couldn't adapt to house two hearts. The question is how and would it takes day to years with medical intervention, or hundreds to millions of years with bioengineering and evolution? And, then, was it worth the effort and adaptations? What is the cost even if any ideal means of doing this is found? Is it better than letting the person die or giving them a heart transplant or artificial heart instead?
I'd finally be a Time Lady! What a dream.
At the thumbnail, I thought, "then I'd be a time lord!"
@@chrystar1 me too!! Lol
Same!
Your videos are so interesting! Our bodies are so incredible, complex, and beautiful it’s so fascinating to have it broken down into short explanations with visuals (I’m 💯 a visual learner so I appreciate how much time you put into your videos SO much!) thank you for all the hard work you put into doing this!
Thank you! Glad you enjoy them!
Absolutely loved your intrigue and enthusiasm! Your tone, body language and delivery made me feel very involved. Kudos!
I don't know enough about the topic to be able to tell you whether you missed anything or not, but I definitely do want to see more videos like this! Further exploration of the "what ifs" of the human body would be fascinating.
Same that's why some things we leave them to the most high GOD
Thank you! This is perfect. I'm working on a sci fi story where my alien character has two hearts. This has helped answer some of my background questions.
This makes me wonder if there has ever been a set of siamese twins with two hearts functioning in one system. If so I would like to see a video about it.
Abby and Brittany Hensel
The krogans from mass effect had multiple hearts. I think some of said hearts worked as backup because they were extremely hard to kill.
I wanted to make a comment on the total knee replacement. I very much enjoyed your lecture on this subject.
I had a total knee replacement in Aug 2021
Had a excellent surgeon.
Almost 2 years later I still have pain,not constant,but makes me wonder why I did,I trade-in one pain for a different one. I belived my age had something to do with it,I have friends that has had this
done and are doing great.I will not have the left knee done. I had the
What want to call the compressor on my thigh.
In my case I had back surgery so they couldn't
Numb me in the back.
After all this time and physical therapy, that
Muscle gets angry.
I wish everyone that is going to have this surgery should listen
to your lecture. I learned
a lot. Thank you.
I feel like the initial questions were perfect for engineers, preferrably hydraulics.
If there was constant pressure and flow, would you need the backflow preventing flaps?
Could you make a video about how the donated bodies are preserved so they don't rot and go bad and you can present them in educational situations repeatedly?
He already did.. he spoke about how they are time donated and must retain every crumb removed. How they apply some kind of fluid and keep the corpses from rotting. He wears cloves all the time.
We already have backflow preventing flaps : )
i have been working on potential layouts, one of which has several micro hearts catering to various sections of the body.. so even if one fails, the human doesnt have to die
That’s where I was in my thinking when I found your comment!
I like this idea!
This feels like people in the futre will try and optimise human body layouts like they optimise game builds now, honestly sounds like fun
There are some siamese twins that have two hearts so it would may be make sense to observe how theirs systems run together and then scale that down.
Great thought experiment! The brain maybe with it's own "remote backup pump" like large aircraft have for hydraulic systems if an engine driven pump fails or needs more pressure (usually electric). Fun stuff! Thanks!
Hey, did you think for a moment all other implications of introducing the other heart? How many songs would have to be rewritten, how many phrases would no longer make sense... Owner of a lonely heart... (a heart would never be lonely!), my hearts will go on, from the bottom of my left heart, etc.
Who ever donated his body is a real on fr🔥🔥
Instead of having one failure point, you will have two failure points. One heart gets suffocated without the other and if the other fails, then you experience loss of consciousness and possibly brain death.
Yeah, unless they're redundant, it seems like it would be a major disadvantage to have two hearts. It's amazing that the heart manages to do what it does for so long, but it is the most likely organ to fail and cause death. With two of them serving different but mandatory functions, I can only imagine life expectancies dropping by a decade or two.
I always wondered a similar question involving a split left and right heart being that the sides technically don’t have connections except for the veins and arteries briinging the blood back, only disadvantage is that the atrium and ventricles would need separate electrical signals to function and i also see no benefit. I thought it was funny and amazing that you literally made a completely new human Essentially and worked out how the vasculature would have to respond!
I have a lot of anxiety surrounding the fact that I'm just kinda a thought thing inside a meat machine. These videos help.
I actually heard a story of a guy with two hearts, I even know the guy even though I didn't hear it from him directly. Of course I haven't seen any x-rays and he's still alive to my knowledge. From what I heard, his body adjusted well enough as he grew, he's generally fine UNTIL the two hearts are out of sync. When they aren't which happens occasionally, he's only capable of lying down and trying not to die until they sync again. And that's all I know.
where did you hear this story?
@@austinroberts8366 I know the guy personally and heard about it from our mutual friend with whom he was way closer. Of course the friend can lie, doesn't really have reason to.
What about a bypass turbo charger. It's like a small pony heart either before or after the main heart. In bypass mode it just allows the blood to flow through but when needed it could help with small extra pumps when the body needs a little
extra volume without a lot of extra pressure?
And/or it could send an extra squirt or two of blood back through the lungs for a double shot of oxygen.....
When not needed it relaxes and opens up to let the main heart do all the work.
Maybe it could open and close a little like a pressure regulator when needed.
That's a really interesting idea... I like it more and more the more I think about it
I think that, to make the body more efficient, we wouldn't need to have another heart, but a third circuit and set of chambers in the one we already have.
The circuits, instead of being the general and the pulmonary, would be the primary (sending nutrients and oxigen from the heart to other organs and collecting CO² and waste), the cleanser (going through the intestines, liver and kidneys to collect nutrients and get rid of the waste) and the pulmonary (getting rid of the CO² and collecting oxygen).
That way organs would be more efficient. For example, now when the kidneys process the blood, the clean and freshly filtered stream gets mixed with the waste-filled blood coming from other parts of the body, but with this system that wouldn't happen.
Isn't the cleanser just doing what the lymphatic system does right now? Like, partly atleast I guess? (I've not learnt much about it so I may be wrong)
@@annanyaverma1810 Partly yes, and more efficiently, but even then the lymphatic would still be necessary, because, even without taking into account the immune system, the excess fluid left by the blood still needs to be drained.
Good point though, I didn't think of that.
Can you make a video about blood groups ? Like what is the differences between each group , what determine our blood group. Why is there multiple blood groups. Etc.....
The Space Marines have 2 hearts and 3 lungs, that would be an interesting video.
If you ever come back to check the comments, I want to ask a question what if you’re a rib that was a surgery to make him space better why you made more space for the heart could you have two of the same size heart and how would you add a new vascularto your body is it possible to add more veins?
I feel like both hearts would end up being smaller and weaker than a single heart. Blood pressure would probably be the same or better than most with a single heart. If you had a heart attack in one heart you might also have a much higher chance of surviving.
Would you have Double the pulse?
Would they beat at the same time?
2:22 that startled me a bit i thought the cadaver moved on its own
Two hearts in parallel, echa one connected to the same arteries/veins as standard. The difference would be the “rest period” at the end of each heart beating cycle. Both hearts would need to be completely out of phase. In short, one heart goes through its entire cycle with a long “standby” period while the other heart beats.
If one fails, the other heart would need to readjust by decreasing the wait period between beating cycles.
Hard to explain in words 🤨 without getting too technical.
It's amazing how a thing like this can have consciousness about itself
Doctor Who does! ❤❤
The Doctor* but damn right! ❤️❤️⏱️
There's a form of heart transplant surgery, the heterotopic/piggyback heart transplant that attaches the healthy donor heart to the vessels, without removing the patient's. It's usually done when removing the original heart isn't a good idea, or very helpful.
But also means that at worst, you could have a human with two hearts, but no other differences in anatomy, and they'd be fine.
Imo the point of two hearts is to have a backup, like almost everything else in the body, if you had a system that depended on two hearts with distinct jobs what would happen if one fails? idk about you but i would like to have less critical failure points in my plumbing. So if either ones failure is going to be game over might as well just have one bigger heart... anyway two hearts in parallel with some cutoff system for blood loss and asynchronous pumping, maybe even some long rest periods for each one in the night or something to repair damage idk.
ps: If we are just redesigning the body here i would like if possible avian respiratory system i hear they are more efficient, maybe even get so extra space for another heart lol.
You only gave the case of hearts operating in parallel (or independently).
A better solution would be having the hearts connected in serial. If one failed, blood would just flow passively through it. The other may have to take up the slack to maintain pressure.
With two in series, each would operate at half power and with less wear and tear, but with a backup already on line to compensate if one fails.
I doubt changes to pulse rate would be too much of an issue, as continuous flow artificial hearts (ie, no pulse) are already use.
Been done. Doctors in Houston transplanted a small heart into a man with a large heart. Two hearts temporarily next to each other
Very interesting. One thought that occurred to me was what if one was merely a much smaller auxiliary heart that ensured flow to the brain. Imagine a system where if we were injured, our bodies would automatically reroute in order to ensure adequate blood flow to the moat necessary for life organs.
I still think the most useful adaptation humans could want would be bi-hemispheric sleep, as some birds have. One side of the brain sleeps while the other maintains awake functions.
Great teaching skills ~ you breaking this down the way you did even us non medical can understand.
We have in fact two hearts combined into one. One is for our gas exchange, the other one is for the rest. So, in this particular point, we are considerably different from fishes (to which we have most of our design in common). Fishes have really just one heart which drives a simple linear arrangement of respiration and body nutrient supply. We have body overtemperature to environment. So we need more degree of freedom for the regulation of heat exchange and for the respiration of gaseous oxygen and carbon dioxide.
What happens if one heart fails? Consider if the heart suppling the brain was working normally while the heart supplying the rest of the body failed completely. You would be aware of your body dying. I think about patients I have cared for who had a necrosed leg due to vascular disease. They were in excruciating pain before amputation. Now consider the entire body undergoing necrosis. Wouldnt live long, but it would be horrible.
Multiple pumps in line are not that unusual for industrial applications. If the second heart were located in the lower abdominal cavity it could be in-line and pump blood from the legs up into the torso. The primary heart in the chest cavity would pump just as it does in the current layout, except the pressure would not drop quite as much between beats. Instead of 120 over 80 (effectively 100) and it could be at 110 over 90 (still the same average effective pressure). The difference between low and high is not a requirement of the pump, it is a result of the flow rate combined with the pressure. In the case of a biologic system, as long as the flowrate and pressure supplies the right amount of blood cells to the lungs, allows sufficient time to dump the CO2 and load them up with O, the rest of the system couldn't care less if there's 1 pump (heart) or a series of hearts (pumps). But the lower heart (pump) has to be coordinated to work in tandem with the upper heart. Sure the brain could deal with this , but some brain cells currently tasked with other chores would have to be utilized. In the end possibly more brainpower going toward running the body and less toward intellectual function. (There's only so much space in the brain cavity).
I often thought that a small “heart” in each foot would be helpful. I maybe might be able to go back to cute socks and ditch the compression hose.😂
Can you do a video on nephroptosis? My grandson recently had kidney surgery, and they found that one kidney was so out-of-place, his surgeon took photos and is publishing an article on it (Vanderbilt Children’s). He also had an artery wrapped around his kidney, which was the original reason for the surgery. It wasn’t til they opened him up that they found his kidney was sideways and way out of place
Don't we already have 2 hearts, one to pump the blood to the lungs and one to pump the blood to the rest of the body?
If I were to add a third heart, I'd put it at a distance along the artery system to give the blood an extra push where it is needed (e.g. to improve leg performance then put it at the base of the spine to provide extra flow to the legs), this would also allow for the current heart to be smaller as it wouldn't need to maintain blood pressure through the whole system.
There should be a video like this talking about how Siamese Twins are wired inside. How does the body know how to connect them since the body is already set up for a single person.
If you could get the "downstream heart" to pump according to what it was sent by the "upstream heart" ("wired in series") that might be better? (Synch by pulse, meaning the upstream heart is in charge). The idea would be that under lighter loads, both would have less work to do, but if necessary they could do "double" the work - up to the usual "speed limit" you have on a heart. If both remained full size, if one failed, you'd need a failure mode where it went over to "free flow", and the other could be "the heart", as we know it (just working a bit harder because of the extra heart in the path).
A use case for "wiring in parallel" might be to have one heart pumping for our gills, and the other for the lungs. But then we need to first get the gills.
Hmm ... you could have bilateral hearts for everything downstream of the head? So if one fails, you lose half your body instead of all of it? I need to get the plumber around next week, so I could ask him.
I've just had an idea how one could survive with one real, and one artificial heart that might not be complete junk.
If you had one heart inside of another, the outer heart could help out the inner heart. That's the essence of it. Instead of thinking in terms of replacing a heart that's not working properly by removing it, and substituting it with something that gets hit by things like "tissue rejection" (one of the scraps of information I've heard about these), wrap it up with [waves hands a bit] that helps it do its job. "Use the old piping", though.
What about two separate circulatory systems that do different things, like circulatory system versus lymphatic system? One could specialize in nutrition delivery and waste collection while the other in circulating oxygen and carbon-dioxide.
Such an incredible idea! I would love to see one heart per lung. Man you really have my brain working! I love the idea of the hearts taking turns!! Seriously the best videos on the internet ❤❤❤❤❤😍😍😍
Awesome! Thank you!
If a person has 2 hearts and has Congestive Heart Failure, would both hearts be affected? The reason I ask is that my husband passed away from CHF. His heart was enlarged twice and his Ejection Fraction was only at 12%. He had a heart cath and it showed that he had no Coronary Artery Disease. He also had a pace maker. His kidneys took a hit because his heart was enlarged and was on dialysis the last few months of his life. His kidneys stopped functioning altogether and became necrotic. He left the Cleveland Clinic after 7 weeks and was sent home with a dobutamine pump. He was on the highest dose, which I think is 5mg/ml. Even with the dobutamine his BP stayed at about 60/42. I would be really interested to know how that would've affected him.
It would be a great video if you would like to touch the topic "what happenes to the body organs when it catch fire? living body in case of fire outbreak accident or dead body when it is on funeral pyre.
I have seen often skull explodes when dead body is cremated on pyre. May be because of the pressure of fluid around the brain. And somany other facts can be revealed in the video.
Chris Isaak sung it:
"One heart can never win, it takes two hearts.
Two hearts, two hearts just to hold love
Two hearts, two hearts just to hold your lo-o-o-o-o-ve
Your lo-o-o-o-o-ve"
(From True Romance soundtrack. Script by Tarantino. Love and bullets.)
Hearts in series, alternating shifts, assume if we're allowing for duplicate vessels we could also allow for the timing to have evolved in a reasonable way
The octopus has 3 hearts: 2 to pull in oxygen from the gills, 1 to distribute to the tentacles.
I highly recommend looking into the anatomy of a Space Marine from the Warhammer 40k universe, they sort of go into detail of how they make space marines, and most importantly, they have two hearts
Interesting - I'll give it a look
@@theanatomylab Dr Chris Raynor covers this too.
Eg
th-cam.com/video/7OXjNpNpWXw/w-d-xo.html
0:53 Literally me trying to organize & clean my room to make space
It would be interesting if, over a person's lifespan, the hearts changed in dominance. When you're born, your left heart does most of the work, while your smaller right heart does less. As your dominant heart ages, your smaller heart grows in pace, until the functionality swap and the left heart is replaced by the right, with freshly grown muscle ready to chug along for the rest of your life.
It could actually reduce wear on both, if we want to maintain a normal blood pressure, the dominant heart could always run a with a bit less force, and the small would make up the difference.
Even with TWO hearts, some people are so wicked , they would still be heartless!
bros explaining like hes building a pc 💀
As someone who is a maintenance electrician 8n the water industry my immediate thought was why not three. Duty, assist and standby is standard pump practice on my sites. They would be in line and cycle their tasks. Duty would run constantly then instead of increasing the BPM during exercise, assist would kick in with standby there should there be an issue with the other two.
We do kind of have two hearts, or at least two sets of pumping chambers each serving separate circulations, the pulmonary circulation to reoxygenate the blood and the circulation to the rest of the body to deliver the oxygenated blood to cells. Our heart consists of both these pumps and links the two components of the circulatory system.
I also thought of star trek, and klingons, the warrior species that have two hearts that are redundant to the degree if one is injured the other still keeps you alive.
🎶 Two hearts, believing in just one mind
You know we're two hearts believing in just one mind 🎶
Not only did this guy make me feel my heart he also made me feel my lungs
Some would argue humans already have two hearts: one for the systemic circulation and one for the pulmonary circulation. In other words, the argument is that the left side of the heart and the right side of the heart are two different hearts. But if a whole separate new heart were added increasing the amount of blood flow, a new question arises of how this would increase lymph flow? How would the lymphatic system handle potential increases in drainage from the blood if blood flow increases from having two heart?
one way I’m thinking about it is instead of an entirely different heart, the main heart we have is cut in half into two smaller two chambers hearts, one for de oxygenated blood and the other for oxygenated blood. Idk just my thoughts
Octopi have three hearts, I believe the central one just handles the circulation to the gills, and the outer two distribute oxygenated blood (each handling one side of the body). The hearts are all two chamber hearts, unlike ours.
Really that highlights the obvious use for a second heart - pump the returning blood to the lungs more actively. I think you could get away with a smaller two chamber heart here - anything at all is enhancing the return circulation anyways.
It seems to me the obvious reason to want this is that you're supposed to be spending time in orbit and your existing circulatory system relies too much on gravity for return from the head, and secondary pumping from muscles you just don't use as much in your limbs. Replace these (very cleverly optimized for life on Earth) systems with the active "return heart" to keep the blood circulating properly, instead of pooling in the head and creating increased blood pressure behind the eyes like it currently does in humans. Your main heart can probably be reduced in size anyways if you're in orbit as you won't be fighting gravity, which gives you more room for your "return heart".
About the positioning. It just came to my mind that maybe the retroperitoneal space could have some sort of mediastinum in it. After all, we can live with a small amount of small intestines missing and would also have the proximity, and maybe the connection, to the abdominal aortic artery and lower vena cava.
Geez it feels like I'm getting ready to build Frankenstein monster haha.
can you do a video explaining colds how they start and what parts they effect and just how they work overall?
I felt like answering the questions. Naturally, the hearts would be of different sizes! Maybe the purpose of the smaller one would be to help blood keep the momentum when going through it or accelerate the blood flow, so the smaller pumps seconds AFTER the big one. And the hearts would be like kidneys: you can still live having the only one, but god forbid you being left with the smaller one. That would be a ban for any hard exercise or activity. Also, less important part, I'd put them one under another.
....aaand then I've watched the video. :D
Run it like a twin turbo. One is in idle and kicks in when you are doing high exertion activities. This should make us much faster beings also. Having higher blood flow to carry oxygen around the body. Of course our bodies would be adapted to this having larger veins and arteries to carry the volume of blood etc.
If I had two hearts, I'd be a timelord!!!
I heard that one patient got second temporary heart (artificial) for several months prior to an operation to provide some "vacation" time to original heart.
Look at Tesla semi - one engine works all the time, the second - only during acceleration. Chest and shoulders could simply be wider.
I love this type of hypotheticals.
It's very interesting to think on these things as it challenges your knowledge on what is actually there already. 🤔
Right??
I came here expecting Doctor Who memes in the comments and I was not disappointed
That cadaver is a hero
very enlightening video!
Living with two hearts can give you two lives.
The Ventricle Assist Device (VAD) provides constant blood flow. Patients don't have a pulse.
I got to see my heart from an echo cardiogram. It is very Kool to see.
Two hearts would require (obviously) an entire re-wiring of the...oh.
Maybe the best place would be have the larger heart where it is and replace "useless" organs like the appendix with the smart heart (have the larger heart work with the upper body while the smaller heart for the lower body) and reroute couple medium vessels from the larger heart to the smaller vessels from the smaller heart so the legs can get enough blood/oxygen
This is a question I have been asking myself for two years now.
Probably not related…
I had WPW (Wolff Parkinson White) Syndrome. It’s you’re born with a 3rd, extra electrical pathway in your heart, instead of 2 like normal.
I was born with it, but it stays dormant until you’re about age 8 and your heart randomly has episodes of rapid heartbeat. Once mine was about 245 BPM. Thankfully my cardiologist decided to do an oblation to zap away the extra pathway when i was 10 years old. That doctor has passed now due to old age but that doctor saved my life.
I’m now 26 years old and completely healthy with no signs of it coming back..
I only speak of this because most people don’t know about it.
Octopi have one main, systemic heart that pumps blood to the whole of its body. But they also have two additional hearts, responsible for pumping blood over each of its gills.
If they could beat in a semi-synchronos fashion to maintain a more constant blood pressure, the overall workload would be decreased while perfusion would remain. I wonder if there's a reason for the fluctuation of pressure we're not even aware of 🤔
Space marines from the warhammer 40k universe have two hearts though they are genetically modified 8 foot tall superhumans. Why did i say all of this i don’t know but hey the more you know
You just reminded me of Dr Victor Frankenstein movie where Him and his partner litterally had to put 2 Hearts in Frankenstein so He could live
I think you missed ANF hormone which is released by the heart which (to some extend) control the blood pressure, blood volume and functioning of kidneys
with two hearts it would be much more complex. lower blood pressure in one heart (due to any reason) might trigger the secretion of ANF which will increase blood pressure (for both the hearts) which might lead to problems. This is based on my understanding on ANF hormone and on the model of two hearts you proposed, do let me know if I am wrong or if I understood it wrong.
ANF function can be quite nuanced, but this is definitely something to consider
Pregnancy would be a risky business with two hearts.. (Along with the foetal circulatory configurations.) We already know that blood volume drastically increases alongside your heart's workload... Yikes.. All I can think of is? Massive amounts of high Pressure for mum... and a bumpy state of survival for bub!
Lots of fish have two hearts, octopus & squid have 3! And some people having a heart transplant leave the original heart in & graft on the new one, so yes two hearts in 1 human body.
Really glad for for your content, using the correct anatomically names and easy to digest them to who doesn't know the terms.
I wish this channel existed when I had anatomy. I didn't understand anything event though we had lectures, labs, and gray's and netters, haha. Only thing that worked was flash the cards :P
I am absolutely fascinated with this content!
This video was good, however, I felt as though you there could have been mention of the different adaptations that would need to happen to facilitate two hearts.
Thanks Reon! I do want to point out that it’s mentioned a few times in the video that the organs and tissues would have to adapt to the new heart, circulatory pattern, etc. It was decided to keep that brief due to time constraints, but the need for adaptation was indeed mentioned. All the best!
I think I saw in some document how body doesn't function well on steady blood flow.
So when hooked up to a machine that circulates blood the body slowly dies.
Excellent hypothetical question & breakdown of reasoning
Yes the scientific thinking this raises is great on a meta level
Oh & is there a time when this might happen in reality ? There looks to be a cardiomyopathy connection where a surgeon may splice in an additional heart in parallel (internet & likely unreliable source here)
"Just follow your heart!"
This guy: 🤔🤔🤔