backtop


Print 63 comment(s) - last by Boze.. on Mar 7 at 12:59 PM


Artificial heart  (Source: popsci.com)
Currently, 50 calves and three humans are using the pump, which completely replaces their natural hearts

Researchers from the Texas Heart Institute have successfully replaced the human heart with a 10,000-RPM artificial pump, which leaves its patients with absolutely no pulse.

Popular Science described the artificial heart, which doesn't resemble an organic heart by any means. Currently, 50 calves and three humans are using the pump, which completely replaces their natural hearts.

Drs. O.H. "Bud" Frazier and Billy Cohn of the Texas Heart Institute in Houston are the creators of the artificial pump. It is able to fully replace the heart and even provide a continuous flow of blood throughout the body -- all without having to recreate a pulse.

Creating an artificial heart has been difficult up until now. Many have tried to make a metal and plastic heart that is capable of beating, but many were unable to continuously beat beyond an 18-month period. Also, metal and plastic have many limitations, such as the requirement of an air compressor outside of the body where a hose through the skin allows the compressor to fill a balloon inside a chamber, which pushes blood to the lungs. The other balloon inflates and deflates in an alternating pattern with the other to recreate the heart's beating rhythm. This is exactly what the Jarvik-7 -- the first machine to replace the human heart -- did in 1982.

There have been other devices, such as the HeartMate ll, which is an Archimedes' screw that assists failing hearts with magnets implanted in the axle and an electric coil in its case where a charge makes its way around the coil, moving the screw at 8,000 to 12,000 RPMs. The axle spins on a synthetic-ruby bearing, which is lubricated by blood, and it's all connected to a portable battery. But the HeartMate ll can't replace the heart entirely.

Cohn and Frazier's continuous-flow left ventricular assist device (LVAD), however, can replace the heart and doesn't require a compressor because the researchers discovered that recreating the pulse wasn't necessary. The trickiest part to creating an artificial heart was recreating the pulse, but Cohn and Frazier found that just using a continuous-flow heart solved the issue of longevity, which is the main issue. One of the turbines used in the artificial heart has been running in a lab continuously for eight years, and it runs on a small battery that the patient can easily carry on their shoulder.

Cohn and Frazier described a recent process where the LVAD was placed in a calf named Meeko, who lived on to lead a normal life. However, he didn't have a pulse whatsoever, which didn't seem to be a problem. Cohn performed the surgery by peeling tissue from around the heart and allowed a heart-lung machine to take over. The heart was cut free, and continued to beat outside of the body. Cohn then sewed collars of rubberized Dacron onto the atria. He then lifted the turbines from a dish of saline with the dolly dresses dangling from them. The dolly dresses were sewed onto the collars, and the turbines were activated.

“That’s what heart surgery is,” said Cohn. “It’s a script. To you, it probably looked like I was just sewing those collars into Meeko’s chest any old way. But every motion was planned, tested, practiced. Turn my hand eight degrees and poke the needle through; swivel my hand back 22 degrees and draw the needle up four inches; turn my hand back just so and bring it to the left a half inch: a precise number of stitches, pulled just so tight and no tighter. What heart surgery takes is remembering an incredibly long and complicated script and following it exactly, step by step.”

Source: PopSci



Comments     Threshold


This article is over a month old, voting and posting comments is disabled

Blood pressure?
By ZmaxDP on 3/5/2012 9:18:54 PM , Rating: 5
I wonder how this impacts blood pressure? Obviously it is still a factor, but I wonder if this will reduce peak blood pressure. That alone could prolong lives by reducing the chance of aneurysms or other high blood pressure related issues. Plus, no heart attacks - it can take a licking and keep on ticking...er...spinning...




RE: Blood pressure?
By Reclaimer77 on 3/5/2012 9:28:43 PM , Rating: 2
Good question.

I was thinking along those lines too. I wonder how a continuous flow pulseless pump will affect plaque buildup in the arteries. If at all.


RE: Blood pressure?
By Etsp on 3/5/2012 9:37:20 PM , Rating: 2
My primary concern with this is what happens to a patient who has one of these devices that suddenly stop working entirely? That's almost certain death. CPR will be ineffective, and there's very little chance of being hooked up to a heart and lung machine within the next 10 minutes.


RE: Blood pressure?
By Reclaimer77 on 3/5/2012 9:40:30 PM , Rating: 4
Well I would assume that would be an issue with all artificial hearts, not just this design. I imagine though that if you have one of these installed, for lack of a better term, you're on borrowed time anyway.


RE: Blood pressure?
By DopeFishhh on 3/5/2012 11:27:42 PM , Rating: 3
I'd say the answer to that is to install redundant systems, i.e. become like a timelord and have a second or even a third heart.

You could divide the power requirements of each heart by the amount of redundant units to scale them down both size and power usage wise. This way you could have a single failure then you chest starts beeping and know to get to the doctor asap.


RE: Blood pressure?
By CityZen on 3/6/2012 12:02:24 AM , Rating: 5
Errr ... you mean RAID 1 hearts?


RE: Blood pressure?
By rs2 on 3/6/2012 1:45:16 AM , Rating: 2
RAID-1 is inefficient. It would be better to build a single heart using a series of smaller turbines such that if one fails the ones remaining in service provide sufficient blood flow to keep the person alive long enough to have the problem fixed.

So more like RAID-5 hearts. With a RAID-6 option for people who can afford an extra redundant turbine.


RE: Blood pressure?
By drycrust3 on 3/6/12, Rating: -1
RE: Blood pressure?
By WLee40 on 3/6/2012 2:49:27 PM , Rating: 3
quote:
I do wonder if there are spiritual implications of having no heart. Has there been any comparative studies between people with only an artificial heart and in comparison to those who've had other types of heart surgery?


Are you serious??!!


RE: Blood pressure?
By drycrust3 on 3/6/12, Rating: -1
RE: Blood pressure?
By ppardee on 3/6/2012 4:09:45 PM , Rating: 5
There is a good reason for people to believe that there is a connection between the heart and the spirit. It is clear that when the heart stops, the body dies. Blood is life in many cultures and the heart controls the blood.

In reality though, if the spirit is tied to any organ, I would say it is the mind. Even then, the mind cannot be the spirit in a Judeo-Christian sense of the spirit. The mind can be damaged, the spirit or soul has to be able to be able to remain whole even if the connection between the two is damaged.


RE: Blood pressure?
By JediJeb on 3/6/2012 4:08:09 PM , Rating: 3
quote:
I can't see any reason why the motor or motors couldn't be pulsed to replicate the actions of a human heart.


The speeding up and slowing down of the motors would cause premature wear and tear on them. Running at a constant speed is less stressful on the equipment and makes it less complicated because it would not need the added circuitry to create the variations in speed.

quote:
I do wonder if there are spiritual implications of having no heart. Has there been any comparative studies between people with only an artificial heart and in comparison to those who've had other types of heart surgery?


The spiritual "heart" is not the same thing as what pumps your blood. Just as saying something is the "Heart" of a company, it just means it is the central focus of that company not that it pumps blood and life into it. A person's spiritual "Heart" is their essence, the thing that makes them what they are. If you are referring to the Biblical meaning of heart, then Matthew 15:18 shows it is not talking about what pumps your blood when it says "But the things that proceed out of the mouth come from the heart, and those defile the man." People even then knew that the mouth and heart were not physically connected, so it is talking about a spiritual center of being not a physical organ of the body.


RE: Blood pressure?
By Devilboy1313 on 3/6/2012 7:49:01 PM , Rating: 2
Yep, all the cows went on to become serial killers.


RE: Blood pressure?
By Camikazi on 3/7/2012 7:02:42 AM , Rating: 4
Talk about mad cow disease.


RE: Blood pressure?
By TSS on 3/6/2012 9:50:15 AM , Rating: 2
Eh kind of. Remember us humans have a minimum heart "beats per minute" before our muscles stop working and a maximum before veins start to burst, but the range in between is incredible. Human hearts can beat between 20 and 200 beats per minute and the human will still be alive.

You could put in 3 smaller motors. 2 spinning at the same time would provide enough pressure for regular day use (office work, enjoying watching TV, reading a book etc). When you need to run or otherwise use alot of energy, the 3rd motor kicks in, your blood pressure rises, muscles get more oxygenated = more energy.

Likewise, when you go to bed one of the motors can spin down to half speed or turn off entirely, to lower blood pressure and enter a "relaxed" state.

In case of 1 motor failing, the 2nd motor would automatically kick in as a backup untill the faulty one can be replaced. You wouldn't be able to run, no. But you would still be able to walk to the hospital. Even in the event 2 motors fails, the 3rd one would be enough power to keep you alive while the ambulance comes to pick you up.

There's never be a danger of too much blood pressure or too little blood pressure - Simply set a minimum and maximum speed those things can rotate at. And ofcourse, hardcode it into the bloody thing so that we don't get any issues about "hacking" or whatnot.

IMO it's a better sollution then our current natural hearts. It might run for 80 years but if it ever fails it's instantly game over. You won't even be able to call for help unless you've got like a 1 button alarm or something.


RE: Blood pressure?
By gmyx on 3/5/2012 9:46:38 PM , Rating: 2
Read the article: It kinda happened to on test subject. They device got disconnected and they collapsed. Fortunately, the person who disconnected them was able to reconnect without issue.


RE: Blood pressure?
By GulWestfale on 3/5/2012 10:52:15 PM , Rating: 2
RE: Blood pressure?
By Sahrin on 3/5/2012 10:49:26 PM , Rating: 3
Q will visit you and give a retrospective of your life up until the moment you were injured in such a way that you required an artificial heart. You'll be given the choice of avoiding that situation, creating a boring and unremarkable existence, or continuing on this high risk path even though it leads to your eventual death.


RE: Blood pressure?
By abscode on 3/5/2012 11:20:35 PM , Rating: 3
My only regret is dying and finding you here.


RE: Blood pressure?
By Camikazi on 3/7/2012 7:04:22 AM , Rating: 2
Just watch out for those Nausicaans from now on.


RE: Blood pressure?
By 91TTZ on 3/6/2012 9:41:40 AM , Rating: 2
If it's small enough, you could put 2 of them in parallel with a check valve inline with each of them. That way they'd be redundant and if one failed the blood wouldn't flow backwards through the stopped one.


RE: Blood pressure?
By Solandri on 3/5/2012 9:48:13 PM , Rating: 5
quote:
I wonder if this will reduce peak blood pressure. That alone could prolong lives by reducing the chance of aneurysms or other high blood pressure related issues.

I wouldn't be so sure. Other biological systems operate off of cyclic stresses. Bones for instance strengthen and weaken in response to repeated stress and relaxation cycles, not constant stress. At a microscopic level, tiny segments of the bone literally break under stress, and the repair process builds them thicker than they originally were, strengthening them. Simultaneously, the body is also eating away at all bone to recycle calcium. Consequently the bones which aren't being stressed end up with a net loss of strength. Astronauts who spend a lot of time on the space station have to deal with this bone loss when they return to Earth.

If the strength of blood vessel walls works the same way, the lack of peak blood pressure wouldn't necessarily result in a lower chance of stroke or aneurysm. Yes the peak pressure would drop. But it could also result in the vessel walls becoming weaker, and consequently more likely to burst under a pressure spike (like, say, lying down in bed).


RE: Blood pressure?
By bupkus on 3/6/2012 12:42:32 AM , Rating: 2
quote:
If the strength of blood vessel walls works the same way
I have a naturally low blood pressure. My systolic is what some others might call their diastolic, often 90 over 65. Would this mean my arteries get insufficient strengthening? Would people with high blood pressure have a responsive strengthening of their arteries and hence not need medications for treatment of their condition? You get what I'm saying?


RE: Blood pressure?
By dark matter on 3/6/2012 2:58:24 AM , Rating: 3
You are missing his point that even you low blood pressure fluctuates. Thus stressing and relaxing your blood vessels.

This would not happen with a constant flow. They would, in affect, not be used properly as they were designed, and so would likely result in atrophy.


RE: Blood pressure?
By Gondor on 3/6/2012 7:39:19 AM , Rating: 2
Precisely ! And this should be the real concern. Blood vessels can and do ruputure on their own, but does this constant pressure operation alleviate the problem (by avoiding pressure peaks) or does it worsen it (by making blood vessels weaker due to lack of "training") ?


RE: Blood pressure?
By JediJeb on 3/6/2012 3:46:43 PM , Rating: 3
Actually your blood vessels expand and contract more due to stress chemicals than just the pulsing of the heart beat. When you have high blood pressure, even though you are getting the pulses you are not strengthening your blood vessels but leading to a "hardening" of them. The constant stress of the higher pressure stiffens the blood vessels which is not good. The least amount of pressure you can have that will still cause sufficient flow is the best situation.


RE: Blood pressure?
By WLee40 on 3/6/2012 2:53:32 PM , Rating: 2
Very good point. I remember reading somewhere that vessels require the pulsations to remain strong which is why research on artificially grown vessels uses pulsatile flow.


RE: Blood pressure?
By gmyx on 3/5/2012 9:44:59 PM , Rating: 2
quote:
I wonder how this impacts blood pressure?


I've head the full article and they address this issue. They blood pressure is steady at ~78. It seems to have not other issues.


Hmm..
By Jahooba on 3/6/2012 12:00:35 AM , Rating: 2
I keep thinking about how snipers and hunters shoot between heart beats. If they had one of these hearts they would only have to hold their breath to become stone-still.

Maybe in the future it would benefit us all to have artificial hearts (properly shielded from EMP's, of course). Just a thought.




RE: Hmm..
By FastEddieLB on 3/6/2012 2:56:04 AM , Rating: 2
Artificial hearts like these will increase the lifespans of a great many people by decades. Many people do only live until their heart stops, though sadly there are others who die from brain decay.... once we have a proper fix for that we'll have more than doubled the human lifespan.


RE: Hmm..
By arazok on 3/6/2012 8:43:33 AM , Rating: 4
My wife has been living with brain decay for decades. It's far from fatal, just frustrating.


RE: Hmm..
By 91TTZ on 3/6/2012 10:15:33 AM , Rating: 2
As if overpopulation and the healthcare crisis isn't bad enough...

Now you'll have people who are realistically dead but their body is still living because they have portable life support systems keeping them alive.

It's understandable if the person is 70 and their heart is prematurely failing, but what if they're 92 years old and their family just can't let go?


RE: Hmm..
By bigdawg1988 on 3/6/2012 10:21:20 PM , Rating: 2
The death panels will get them!

Sorry, I couldn't resist....


RE: Hmm..
By Reclaimer77 on 3/7/2012 2:59:21 AM , Rating: 1
First off, there is no overpopulation problem.

Secondly it's highly unlikely a doctor would approve a surgery this major and risky on a 92 year old. Their body couldn't take it or the recovery.

Third, wtf is wrong with you? This is an amazing medical advancement. Just stfu for two seconds and think before you open your mouth.


RE: Hmm..
By Belard on 3/7/2012 6:20:36 AM , Rating: 2
Yes, there is an overpopulation problem. We are using more resources than the Earth can reproduce. Fishing fleets are going out farther from land. Almost every area that has land, its used for crops to feed human and cattle (to feed humans).

Do a flyover on the USA... after you leave the cities, its farm, farm, farm, farm, farm. If we flew over the USA 200 years ago, it was woods.

A simple example is hunting... we have hunting seasons for various kinds of animals for POPULATION control. Too many of a certain animal and there isn't enough food, or they over eat another animal.

With humans on this planet, just over 7 Billion... we have problems.


RE: Hmm..
By Boze on 3/7/12, Rating: 0
RE: Hmm..
By fleshconsumed on 3/6/2012 9:34:22 AM , Rating: 2
Don't you mean between taking breaths of air? Typical resting heart beat in a healthy male is between 40 and 60 beats per minute, that's one every 1-1.5 seconds, too fast to time your shot between heart beats.


RE: Hmm..
By 91TTZ on 3/6/2012 10:38:15 AM , Rating: 2
quote:
Don't you mean between taking breaths of air? Typical resting heart beat in a healthy male is between 40 and 60 beats per minute, that's one every 1-1.5 seconds, too fast to time your shot between heart beats.


Typical resting heart rate for a male is 60- 100 bpm. 40-60 is usually only found in athletes or people with problems.


RE: Hmm..
By Solandri on 3/6/2012 2:40:30 PM , Rating: 3
quote:
Typical resting heart beat in a healthy male is between 40 and 60 beats per minute, that's one every 1-1.5 seconds, too fast to time your shot between heart beats

No, it's between heartbeats. I used to do that all the time when taking handheld photos in low-light, before they came out with image stabilized lenses. You can brace your arms against your body to eliminate their motion (using the much larger mass of your torso as a stabilizer). But you can't stop your heart from beating. The camera movement due to your heartbeat is pretty obvious when hand-holding a mild telephoto like 100mm.

You train yourself to relax and your heartbeat lowers to around 60-70 bpm, and there's just enough time after the beat to snap the picture. The rule of thumb is you need a shutter speed of about 1/f.l. to avoid camera shake in a handheld shot, so with a 100mm you'd expect to need 1/100 sec or faster shutter speed. But I was regularly able to get clear shots down to 1/30 or 1/15 sec.


RE: Hmm..
By JediJeb on 3/6/2012 3:53:32 PM , Rating: 2
Yes, it is definitely between heartbeats for a gunshot. If you get much over a 4x scope on a rifle you will be able to see your pulse as the cross hairs move. Lying down prone helps but if shooting while resting your arms on your legs you will see it very well. One guy I know prefers to do up to 300 meter shots using non-optical sights simply because he is not distracted by this using them where he would be using a scope.


In 10 years from now
By Etern205 on 3/5/2012 9:21:21 PM , Rating: 2
we all be looking like T1000.




RE: In 10 years from now
By FITCamaro on 3/5/2012 10:54:36 PM , Rating: 2
I would so fuck with people. Not that I want my heart replaced. But if I did have one, I'd go around saying I'm a vampire.


RE: In 10 years from now
By vapore0n on 3/6/2012 7:32:05 AM , Rating: 3
Id lay down on the floor, fake my own death

beeeeeep
no pulse, this guy is gone

AAARRRGG!!!
scare the sh** out of all


RE: In 10 years from now
By JediJeb on 3/6/2012 3:56:12 PM , Rating: 2
Then someone runs up with a set of defibrillator paddles and shocks you and the pulse shorts out the artificial heart. Oops :P


Sooo...
By Motoman on 3/5/2012 11:09:10 PM , Rating: 4
...can I overclock it, to like 11,000 RPM, and then be even more of a sex machine?




RE: Sooo...
By CityZen on 3/6/2012 12:04:49 AM , Rating: 2
This goes to 11 !!!


RE: Sooo...
By TSS on 3/6/2012 9:52:21 AM , Rating: 3
Vegeta, what does the scouter say about his heartrate?

IT'S OVER 9000!


Variable speed?
By djc208 on 3/6/2012 7:59:28 AM , Rating: 2
So how does this handle needed changes in blood flow requirements?

Heart rate changes based on a lot of factors, the most common would be stress or excertion. If you were to start excercising, or are working hard, is the flow sufficient for that or do you have to "turn it up"?

With no original heart I can't imagine it has any way of knowing when to change blood flow automatically.




RE: Variable speed?
By OCNewbie on 3/6/2012 9:59:11 AM , Rating: 3
I was wondering the same thing.

This would probably also change the way people bleed. Like, when you see in movies someone get stabbed in the neck, and their blood comes out in spurts... I guess this would just gush out in a constant stream?

I wonder if this would affect blood clotting in a wound, or otherwise. Like, would the fact that the blood was constant, and not ebb and flow, affect this? I didn't stay at a Holiday Inn Express last night, so I'm not sure.


Power
By Paj on 3/6/2012 7:13:34 AM , Rating: 2
It seems that the issue with any of these sorts of artificial organ replacements is one of power. I imagine this is powered externally, like previous artificial hearts.

It would be amazing if they could somehow build a device that's powered by the biochemical reactions used to extract usable energy from food. Maybe relying on the conversion of ATP to ADP in the bodies cells or something like that.




RE: Power
By rpsgc on 3/6/2012 9:09:49 AM , Rating: 2
Exactly.

Until they ditch those silly batteries and make it run on ORGANIC POWERâ„¢, these aren't much of a breakthrough.


Better option
By elderwilson on 3/6/2012 8:30:39 AM , Rating: 2
While the idea of a completely artificial heart is intriguing, the better option is to grow a new organic organ. In 5 to 10 years that should be available.




RE: Better option
By ClownPuncher on 3/6/2012 5:27:38 PM , Rating: 2
I want one that's bullet proof.


definition of death
By bebimbap on 3/6/2012 1:41:15 PM , Rating: 2
Most doctors pronounce you dead when your heart has no distinguishable pulse.

So technically are you a zombie?




RE: definition of death
By Boze on 3/7/2012 12:59:22 PM , Rating: 2
quote:
Clinical death is the medical term for cessation of blood circulation and breathing
from Wikipedia

Pretty sure people can still see your chest going up and down. In fact, I love watching for that in movies and television where there's a "dead" person.


EMP
By fstarnella on 3/5/2012 11:35:49 PM , Rating: 1
If you get caught anywhere near an EMP, you're a goner!




RE: EMP
By acer905 on 3/6/2012 12:55:25 PM , Rating: 2
Pacemaker. SO THERE


Robert Conrad commercial
By fic2 on 3/6/2012 11:48:08 AM , Rating: 3
quote:
and it runs on a small battery that the patient can easily carry on their shoulder.


Cue old Robert Conrad Eveready battery commercial:
I dare you to knock this battery off my shoulder...
http://www.youtube.com/watch?v=lr-oLQgvcuk




The need for a pulse
By benjsc on 3/5/2012 10:19:13 PM , Rating: 2
You've got to wonder what other side effects not having a pulse will cause. For instance, coagulation of wounds may take longer due to the continual flow of blood vs the brief pauses. Continual wear on artery/vein walls with no 'down' time for repairs - despite being ever so brief with a pulse.

You can equate it to putting oil in a car. I can put any oil in my car and it will run. But using the correct oil it will run better and last longer.




What - that's impossible
By P4R on 3/6/2012 4:22:20 AM , Rating: 2
IT'S OVER NINE-THOUSAAAAND!




OMG it's happening!
By TSS on 3/6/2012 9:55:20 AM , Rating: 2
quote:
It is able to fully replace the heart and even provide a continuous flow of blood throughout the body -- all without having to recreate a pulse.


Being alive without a pulse eh?

Sounds like a zombie to me.

Guess it's time to dust off the ol' double barreled shotgun...




Medical school of the future
By Quake on 3/6/2012 10:03:06 AM , Rating: 2
I can imagine the requirements of future Medical schools now. Requiring a Bachelor of Mechanical engineering diploma to be accepted in Medical school.




Dyson
By kwrzesien on 3/6/2012 11:01:27 AM , Rating: 2
...will come out with a model that never loses suction!




"I'd be pissed too, but you didn't have to go all Minority Report on his ass!" -- Jon Stewart on police raiding Gizmodo editor Jason Chen's home














botimage
Copyright 2014 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki