You're heart is the most remarkable organ.
In your lifetime it will beat several billion times.
For me, the heart has always been an object of fascination.
It's central to our study of anatomy, and emblematic of life itself.
It starts to beat just four weeks after conception ands it never stops until the day you die.
I think the human heart is as beautiful as it is mysterious.
So this is really the first time I've ever heart a human heart in this context in,
in this way. It's very difficult really to express how amazing it really is.
It tries to do whatever we ask of it and we just assume that it's going to keep up.
At maximum performance, it can eject blood
70 to 80 kilometres an hour and meet, pretty much, every demand we'll ever put on it,
so long as nothing goes wrong.
But it can go wrong and understanding how to mend
it has been one of the greatest challenges of medicines ever-searching journey.
That journey has taken us from antiquity to the frontiers of
modern medicine, and leads us to some of the acute dilemmas
that doctors and surgeons struggle with today.
Across the world, finding a way to mend the heart has become something of a quest.
This man's survival depends on an artificial heart powered by a pneumatic pump in a rucksack.
You can't even just really comprehend
taking your heart out, you know.
Without a heart you're not alive.
And in one of the most ambitious areas of research, scientists are actually growing new hearts.
Now we'd like to think that we've opened a door for building complex
tissues and organs,
and that the world of transplant may change as a result.
Despite all of our research, despite all of our efforts to understand it, much of it remains a mystery.
But millions of us will see our hearts falter and fail.
What I'd really like to know is can you mend a broken heart?
I'm going to meet someone who thinks of himself as being one of the luckiest men alive.
I'm here to play a game of squash, which for me is quite a rare event,
I even had to borrow this racquet.
But the guy I'm going to meet was so unwell that until seven months ago
he was unable to play squash, he never played football, never played tennis.
In fact the things that we take for granted in everyday life, even those were tricky for him.
But all of that's changed now and it's not entirely clear to me who's going to win this match.
I'm playing against 27-year-old Max Crompton.
Until a few months ago, he couldn't play any kind of sport.
And that's because Max was born with a heart that didn't work properly.
The reason he's able to play so well today is that he's one
of the rare people in the UK who's been given a new heart.
And he's clearly making the most of it.
Did anyone point out to you that this
might not be the most sensible game for you to have a go at playing?
You would have thought that I'd go for a less energetic game.
It's everything I've never been able to do.
And what were you worried about that first time?
The strain on my heart, I suppose.
Er, it going really, really, really fast.
I'm seven-nil down against a man who had a heart transplant six months ago.
I don't think I expected you to be like this.
I mean, you know, if I didn't know, I wouldn't know.
Well played, good game.
I think I need to work on my game a bit.
When you look at Max you have to remind yourself that he's alive
because he has someone else's heart beating in his chest.
And, Max you're now the proud owner of a new heart but, you know, how do you
feel, how does it feel different, this heart and your own heart?
It's quite an emotional thing, saying bye to your old heart and hello to a new one.
It really is a lot, it is a lot. Because my heart was very poorly.
And so at the end, it's like you're laying it to rest almost,
you know, like its struggle's over now, you know.
Max's transplant has transformed his life.
But this new heart isn't easy for him to hold on to.
Every day it needs looking after.
Max has to take anti-rejection drugs to stop his immune system from attacking it.
Its longevity is uncertain.
What have the doctors told you to expect?
They give you the official number which is I think ten to 15 years life expectancy after transplant.
It's quite likely that I probably won't get to old, old age.
But at the moment my life stretches certainly years ahead, which is fine, you know.
Even the next ten to 15 years, you know, like that's a long, long time
when you've been living so long under the cloud of, "I don't know if I can make it to Christmas..."
Heart transplants are not a solution for everyone.
There just aren't enough to go around.
And despite improvements in anti-rejection drugs, they still don't last a lifetime.
Max is a pioneer, he's one of the first of a generation
who've grown up and survived congenital heart disease
and in that respect he represents the leading edge
of everything that medicine and surgery can offer us today.
Had he been born a decade or two earlier, he almost certainly wouldn't have survived.
But he's here today, the survivor of a heart transplant, one the greatest medical advances
of the 20th century.
40 years ago, when transplants started, America was awash with hope.
They were a chance for doctors to play god.
But these elaborate operations weren't going to be a solution for everyone.
Because even then donor hearts were
in short supply. And it started to become clear that when it came to heart transplants,
demand would always outstrip supply.
It's in America that the race started to find an alternative to transplantation.
looking for new solutions. It's here in America that
the race started to find an alternative to transplantation.
One of the most obvious questions was could we build an artificial heart?
It was the 1960s and here in America science and medicine must have seemed nearly unstoppable.
They had atomic power... the first men were about
to walk on the surface of the moon and the first human heart transplants had been performed.
So confident were surgeons of their abilities that they had set a date by which they predicted the first
total artificial heart would be perfected and human transplants would be a thing of the past.
That date was Valentines Day 1970.
Four decades later and that goal remains elusive but that hasn't stopped people from trying.
I've come to Oklahoma,
where the misplaced optimism of the '60s has given way to a much more realistic aspiration.
A piece of medical technology which can actually replace the biological heart.
Dr Long?
It's called the SynCardia temporary total artificial heart.
It's made of plastic and weighs 160 grams and is a little larger than a biological heart.
Essentially, it's a heart that's powered by a pneumatic pump that you carry around in a rucksack.
Tell me a little bit about how you went about putting this, er, this remarkable device in his chest.
The first thing is to leave in place the filling chambers but we remove these
working portions of the heart in opened up model here.
Then we re-divide the great vessels up here that go out to the lungs or to the body here and what we're left
with is a cavity. We're looking down in an open chest, er, it's pretty ominous, to be honest,
looking down and knowing that, you know, you've now taken this guy's heart out.
So the failing biological heart is removed as in a transplant.
The total artificial heart is implanted and temporarily replaces the function of the old heart,
until a suitable donor heart can be found.
And that's where you come back in, once Jim's finished all his hard work, it's over to you, isn't it?
Absolutely. And as a cardiologist, to
care for a patient that no longer has the organ that you've spent so much time studying and learning about and
how manipulate and how to care for, no longer do you need to worry about
that and that's really been kind of a remarkable learning process for us as well.
These pumps, which to the casual observer look like, look like a washing machine part,
but that would be to completely misunderstand and under appreciate its complexity and its beauty.
This thing needs to be implanted in a human being, it needs to work seamlessly and reliably for millions
of beats. The valves must never stick, blood must flow over its surfaces without clotting, the pump
must never leak and a person's life totally depends upon it. I am frankly in awe of it.
Doug offered to take me to meet one of the few people in the world
who is living at home with an artificial heart.
Troy Golden was the second person in America to ever leave hospital with one of these inside his chest.
Troy had come to us and had had a long history of heart disease.
He suffers from a disease that he was born with.
Physically he wasn't even able to get out of bed any more, could barely bare weight, could barely
breathe comfortably. Emotionally, mentally, spiritually,
he had reached a point so low that most of us can't even imagine, where literally another day alive
the way that he was, almost any other alternative seemed better than that.
I can't wait to see how his life has changed.
It's awesome to be out of the hospital
and to be able to come back home and to get back to some kind of a normal life.
It's just unbelievable how nice it is to be able to
come home and be with my family, to sleep in my own bed is awesome.
The thing that really struck me was the sound of the pneumatic pump that powers the artificial heart.
We can hear, we can hear the freedom driver now,
are you getting used to that, is that something you're aware of?
Yes, I really have got to the point that I don't even really
notice it, other than it's, you know, it's loud.
I think for my wife she can hear it beating so she knows that I'm alive so it's very comforting
to her.
And then Troy rather surprised me.
He suggested we take a walk over to the chapel where he normally preaches.
It's mind blowing to think that he just doesn't have a heart inside his chest.
And that it's been replaced with plastic and tubes attached to
a pneumatic pump inside the rucksack on his back.
It seems remarkable to me that after everything you've been through,
you were literally at death's door, and yet, you know, with your artificial heart,
you know, we've just had a walk over from your house and you yourself have been here in the church.
You are even at this point transformed from the man that
you were immediately before all this happened.
I had gotten to the point that I was unable to preach.
It's been about a year since I was
been able to, erm, really function at all in the church.
How do you feel now you have an artificial heart?
You can't even just really comprehend taking your heart out, you know...
Without a heart you're not alive.
So, erm, it's...
It's just hard to even think about that.
But once I had come to the point that this is going to give me life,
erm, afterwards...
it's just...
I was just joyful to see myself improve so much, so quickly.
It's really amazing that Troy's alive.
But it's not perfect, you know, I mean that's a huge backpack,
and that constant thrashing around in the background, and even he himself
doesn't feel like he'll get back to 100% just with that pump alone.
But it is a bridge that will get him to transplant,
it is at least that, and it offers hope where there wasn't any before.
But all of this is just temporary.
Replacing a failing heart with an artificial one
isn't the holy grail scientists once thought it was.
To me, this doesn't look like the answer to mending failing hearts.
But cardiac medicine isn't my field.
I wanted to talk to someone who has lived through this changing age of
heart surgery and who might be able to help me find a better answer.
Dr John Elefteriades is one of the worlds leading cardiac surgeons.
Six months ago I saw him bring someone back from the dead in one
of the most incredible heart operations I've ever seen.
We're debating about the exact extent of oure disection.
Gosh it's every bit as impressive
as it is on the scans.
Impressive for you, is intimidating for us.
He has performed over 250 heart transplants and in his working
lifetime has witnessed the evolving science of cardiac surgery.
Over that time he's started to think we might be looking at hearts in the wrong way.
Today I've come to pick his brains while he fixes a different kind of engine.
Have you got the wrench, there? There you go. Thank you.
And John, we've been sort of looking at some very mechanical solutions to the problem of heart failure.
It looks to me like we approach the dream of an artificial heart,
as though it is a big complicated engineering problem.
What do you, what do you think of that approach?
Well, I think it has a lot of merit, but it's not the whole story.
The human body is not just a car,
it has a lot of, er, responsiveness, it has a lot
of hormones, a lot of nerves that, er, connect to the heart.
And there's no doubt that what we do by replacing the mechanical function is an oversimplification,
but that's what we're capable to accomplish right now.
And do you think that the dream of the artificial heart has been
so elusive because we've made that mistake, because we've thought of it as we do your Pantera, as something
that if with enough brute force, we will engineer our way out of it?
I think so, yeah. I think we're thinking of it like a fuel
pump or a water pump, and the human heart is really much more than that.
Now if we step back a little to the present day, what's coming our way?
I think that there is room for...
..mechanical devices and for novel surgical procedures.
I think we will make substantial progress.
But really I think that the future lies in molecular biology and cell based therapies.
What I do every day is plumbing.
I think it's incumbent on us to raise the standard
of heart care above the mechanical plumbing level,
eventually to a molecular biologic and genetic level.
We draw that analogy, don't we, of the surgeon as the mechanic,
as an individual servicing the machine that is the human body.
And that analogy stands, I think, but only so far.
We need to rise above simple mechanics and embrace the complexity of biology.
When you talk to John, you realise that it's
not a problem simply of brute force engineering.
It's not something we can crack just by chucking money and technology at it.
If it was, we would have found the answer by now.
This is the 21st century. We walk in space,
we collide particles at nearly the speed of light
and we know the age of the universe, so why with all that
science and technology has to offer us have we not come up
with something better than the human heart transplant
as a solution to the completely failing heart.
In my day to day work in medicine,
I've come to better appreciate the heart.
As a medical student, I thought of it as little more than a mechanical pump.
But as time went by, it began to reveal its complexities.
Eventually, this wonderful thing of biology began to unfold before my very eyes.
This is the heart as I first came to know it
in the dissection rooms when I was a medical student.
When you look at it, already there's a hint of the complexity that lies beneath.
These are the muscular walls of the ventricles,
whose job it is to deliver blood to the lungs
and around the heart through these great vessels.
But when you look at it like this,
as an inanimate and long dead object,
it really doesn't do it justice,
you can't really appreciate how beautiful and dynamic it is in life.
You really can't appreciate the wonderful feats of which it's capable.
I want to find out what the human heart can do when we push it to the limits of its capabilities.
So, with some trepidation, I've come to Berkshire, to the training camp
of the British Olympic Rowing team.
Pete Reed and Andy Triggs-Hodge already have one Olympic Gold.
And they're hoping for another.
Have a look what our hearts look like.
These guys have two of the most impressive hearts in the world.
Cardiologist, Len Shapiro looks after some of the top athletes in the country.
And, Len, this is an echo cardiogram that we're doing here,
which in hospital medicine we don't usually do in health.
There's no need, erm, erm, but, but what is,
what information does it give us.
Well, the, the unique, advantage we have here, is, that ultrasound,
or echocardiography will allow us to examine
the structure of the heart and it's function.
What makes the heart so remarkable
and so difficult to mend, is that it is a fantastically dynamic organ.
And it is this ability to change,
in different moments of your day and across your life,
that I've come here to investigate.
Slip the shirt off, lie up on the bed.
The first thing Len wants to check is my resting heartbeat.
Erm, your resting heart rate here is not too bad, it's about 75.
I'm obviously nervous about getting on the rowing machine with Olympic rowers today.
I would be too. And I don't know if you managed to notice
what Pete and Andy's resting heart rates were?
I would think it's well below forty, if we were to record their heart
beats over night, which is done sometimes,
it may well be in the thirties or below.
Now that's incredible, isn't it, if you saw that in an accident
and emergency department, you'd be reaching for drugs and people and help?
Already my heart is showing signs of being quite impressive.
Just lying here, its muscles are working twice as hard as
my leg muscles would be if I were out running.
But I've come here to see what happens when my heart is pushed to the limit.
Pete, Andy. How you doing?
Have the finalised the places in the boat for 2012?
I think I'm an unknown quantity here.
Over the course of a day my heart pushes 2,000 gallons of blood
through 60,000 miles of blood vessels.
If I'm just sitting at home doing nothing,
my heart probably puts out about five litres a minute.
When I get up to maximum exercise, it probably goes to five times that, twenty five litres a minute.
Keep going until you can't take another stroke.
The Gold Medal winners thought I wasn't giving it my all.
Don't stop. Keep going, keep going until you can't take another stroke.
Come on.
Really work it! Last few strokes!
I think that's probably enough.
And so what you're seeing there is...
me repaying my oxygen debt with the...
I have to pay for being so unfit compared to the guys.
You know, what they literally take in their stride...
..it's me working at full pelt,
full sprint physiology, fight or flight.
And so you know going into this very inefficient metabolism.
And it's kind of like running out of...
coal in your house and burning the sofas to keep warm.
Lots of toxic by products.
My heart rate getting up there to 190 beats per minute.
You know those guys are going to do that for
another eight minutes, they've been doing it for about six minutes.
The glory of the human heart is that it can adapt so rapidly and so often then still recover.
And for trained athletes, it is capable of
truly astonishing change.
SHOUTS OF ENCOURAGEMENT
How you doing, Pete? All right? That's you at full tilt? Yeah.
Len told me that in pushing my heart as far as I could it went
from pumping four litres a minute of blood around my body to 15.
The boy's hearts went from pushing seven litres a minute to 45!
And yet their heart rates only rose slightly while mine more than doubled.
When you are exercising your heart rate rose to 192 beats per minute, and most
of the increase in cardiac output from your exercise, was due to your increase in heart rate.
Your heart didn't get larger to accommodate.
In contrast, the two rowers their heart rates rose much less
and their hearts got larger to accommodate
the increase in exercise, so they were largely made up
of what we call and increased stroke volume and that's the amount of blood pumped on each heartbeat.
So your heart doesn't just speed up and slow down during the day.
It can get bigger, it can grow when you train it
and will keep up with whatever you throw at it throughout your life.
It is an organ in a state of continual change and that's what makes it so difficult to fix.
And so what we're beginning to build is
the picture of this object with layer upon layer of complexity.
And that's before we try to superimpose
ageing and disease and all of the unpredictability that they bring.
That, I guess is, is why it's been so difficult to find a way to repair
or replace it, that's why it remains as one of medicines greatest challenges.
This is what we're up against.
We need to find ways of mending something that
has elvoled over many hundreds of millions of years.
So I've come here to Minnesota to take a rather unusual voyage inside the heart.
To see how scientists are trying to save lives by assisting the hearts function rather tha replacing it.
Because if you want to mend the heart you need to be able to understand its dynamics.
The University of Minnesota has been at the forefront of mending broken hearts for the last 50 years.
Hidden away in its basement, scientists have found a rather
unusual way of looking at the heart and in doing so, have come up with improved ways of fixing it.
Hi, Paul, I'm Kevin. Pleased to meet you, come on in.
Paul Iaizzo is a professor of surgery at the Visible Heart Lab.
He's perfected a technique for bringing dead hearts
back to life giving scientists the opportunity to study the heart in motion.
What we're gonna do now is we're going to cardioplegia his heart,
remove it, just like they would just for a heart transplantation but instead of planting it in
another animal, we're going to put it on the visible heart apparatus.
Paul's been delevoping this technique for donated human hearts that aren't suitable for transplant.
For today's work, they'll use the animal heart that
most resembles ours in size, structure and function, that of a pig.
The heart is taken off to be prepared
and an hour after it stopped beating,
Paul is ready to reanimate it.
And you're about to take this heart, which you stopped
with a...with a solution, some time ago now, and you're going to make it beat again?
That's the hope here.
And that helps you because.
Because now we can really study functional cardiac anatomy.
If they can get this heart beating again it will give remarkable insight into function.
All right, so now we're flushing, it's warming up,
and you can actually see some spontaneous contractions occurring.
Yeah, I see it. A gently fibrillating heart.
To bring it back to life, Paul gives it an electric shock.
So one shock did it. Now we've got... Oh, wow.
..our pressure developed here, by this heart.
So you can see the ventricular pressures are back, right ventricular pressures are back.
And so, basically, it's a little arrhythmic now,
but, you know, in a few minutes,
um, we'll get back to a more normal rhythm.
Well, that's fascinating. It's really quite amazing
to see a heart re-animate like that, I think.
Now that the heart is beating again, I'm going to be able to look at it
in a way that wouldn't otherwise be possible.
And if we actually dim the lights in the room, I'll be able to give you a tour of this functional anatomy.
Th-that's... That's amazing!
Using a tiny fibre-optic camera, they can get right inside the heart
and examine every aspect of its internal structure.
I'm watching this and I'm reminded of that film -
I don't know if you ever watched it - Fantastic Voyage -
where those guys shrink themselves down
and go flying through the body in this thing
and it's bizarre cos this is the real voyage,
you're really in there with cameras, we are really seeing this stuff.
I agree that it is like a fantastic voyage every time
and it's a different voyage in every heart.
Every heart's anatomy is different.
We look at this functional anatomy - how delicate, but yet complex.
Gosh, you could watch that for ever. That's just amazing.
Seeing the heart like this makes me appreciate what it is we're trying to mend.
These inner workings are like no piece of engineering I've ever seen.
I'm staring right at the anterior papillary muscle here.
You can see the whole length of the muscle coming up to the chordae tendineae,
coming up to those anterior leaflets.
They still look to me very fragile for something that has to do that
72-odd beats a minute, 24 hours a day,
a billion, two, three billion times in a lifetime.
That they can be engineered for that tolerances is incredible. It really is.
This is the result of hundreds of millions of years of adaptation.
And I can only imagine that this has allowed you to gain an understanding of the heart
that just must enable you to design all sorts of devices, all sorts of therapies?
What it gives you too is a new 3D visualisation in your brain
of what that functional anatomy looks like,
so it might allow you to even be more creative
in the fact that you get to understand that
and then to think that you're going to put devices in there
that can be curative for individuals.
It's really rather amazing.
When it comes to mending hearts,
the ambition they have in this lab is more modest than what we've seen before.
By understanding its complexities in this way,
it makes complete sense that we should be helping the heart rather than replacing it.
And it's in bringing biology and technology together that we might just find an answer.
I've heard about a rather unusual collaboration back in London.
Professor Reza Razavi is a cardiologist
and Professor Nic Smith is a biomedical engineer.
Together they have come up with something rather special.
They have combined their skills and designed a virtual heart.
It shows precisely how a patient's heart is contracting,
how blood flows inside it,
and reveals exactly how well it is functioning.
A mathematical model, in many senses,
is just a way of taking all the fantastic imaging data
that's now available
and putting it into one place where we can then start to say,
"What happens if we do this or that?"
In reality, it's just a way of encapsulating everything we know about this particular patient,
allowing us to understand what's going wrong and how we can then make that go right.
And already they're starting to use it to mend broken hearts.
This patient here today is having a pacemaker fitted.
This patient's heart's not working so well, what we call heart failure.
And this pacemaker allows us to resynchronise the contraction of the heart
and help the heart work aerodynamically in a better way.
Pacemakers fail in over a third of patients
because it's not always clear
where to place the wires using a two dimensional X-ray.
What we are doing differently is that when you do this procedure,
you would do it in a standard way in everybody.
But we have taken information from images before we implant the pacemaker,
and use that in real time during the implantation procedure
to help optimise it for that patient and see if that really benefits them.
Thanks to the three-dimensional virtual heart,
the surgeon today is able to see exactly where to place the wires
so that the pacemaker has the best chance of working.
I think the real significance of what they're doing here is something rather grander.
It's something we've never seen before in medicine.
Well, what we see here is the patient that we've just seen this morning being implanted.
It shows the process of how we build a model from that particular data.
So we start off with this MR data
and then after that we have techniques
for segmenting out the parts of the heart which are the tissue,
and then we morph our mathematical model
so that it fits exactly the anatomy of that particular person's heart.
That provides a wonderful platform
to understand and predict what function we'll have.
The information accumulated by the doctors before and after treatment
means that they can create a personalised model of your heart,
capable of being experimented on without harming you.
The models provide an amazing testbed to try options
that we can't try on the patients for obvious reasons,
to find a close to optimal one
before making that particular change in that particular patient.
And this research is more than just an esoteric fascination with all the numbers and all of the science.
It does mean something to patients, doesn't it?
For sure. You know, when we sit in the clinic and the patient walks in,
they're worried about something, they have symptoms,
you know, they're short of breath or they have some pain.
You examine them to try to find out what's going on.
But getting to the bottom of really what is the physiological process
that makes them ill specifically in their own way
requires something much, much more, sort of, deep and well thought out.
These models allow us to do that - they're like a simulation, an avatar,
of what's going on for that individual patient.
If each of us could have our own virtual heart,
doctors could trial medications or procedures on it before applying them to the individual.
This is really exciting stuff
and I think it's the closest thing I've yet seen
to a renaissance in this area of science.
In medicine, so often, we just have to do things
because we know simply that it works on a population basis,
and here actually you can ask the hard questions,
keep asking them all the way down.
That's important because if we're going to understand
how this stuff works, how it's going to make
you as an individual better, we need to understand YOUR heart
and we need to understand the individual,
specifically what we need to do for you.
And this is a good part of the question
and the answer to that question.
This coming together of biology and technology could transform the way we approach cardiac medicine.
Being able to predetermine what would help a failing heart
could help us intervene earlier before any real damage had happened.
But there is a very different way of mending broken hearts,
in some ways the most exciting -
one that draws on the body's ability to fix itself.
This is an area of medicine where mystery and possibility come together,
an area which is teaching us about the heart's healing properties -
properties that have only recently come to light.
That thing beating in your chest from moment to moment,
is capable of some remarkable behaviours.
Behaviour that, until recently,
we didn't realise it was truly capable of.
And so I'm off to meet an incredible little girl
who's something of a medical mystery
and who's living proof of what an enigma the human heart really is.
What's in your bowl, Hannah? What's in there?
A frying pan. A frying pan!
This lively six-year-old girl from Edinburgh is teaching us something about the heart that we didn't know.
In her short life her heart has failed five times.
And each time the doctors treating her have tried every method they can think of to keep her alive.
We've been hearing Hannah's remarkable story. I wonder if you could tell me a bit about that.
I don't know how much I can tell you about her. She's a mystery to us.
Hannah came along
and she was in dire straits, she was in a terrible situation.
She was in heart failure and the only thing we could do was to put her on a Berlin Heart.
The Berlin Heart is an extreme option for a six-year-old,
but was used on Hannah because nothing else was working.
It temporarily took over the pumping action of her heart while she waited for a donor.
But within just a few days, her failing heart did something the doctors did not expect.
But something unusual occurred.
When Doctor Kirk who's our cardiologist
started looking at her heart a few days after her Berlin Heart,
he started to find that the heart was contracting pretty well,
something which we hadn't seen before.
Something completely unexpected happened.
It seemed that in letting her heart rest, it had managed to heal itself.
She was sent home,
but a few months later her heart failed again.
But we could not give up hope on Hannah
and we brought her back to Newcastle
and I put a Berlin Heart in her again.
The heart again recovered,
and, um...
and we took the Berlin Heart out.
So, that was a fourth operation.
We took it out and she managed to make a recovery from this.
And...
..cross our fingers, she still remains OK.
It's now been a year since the last time Hannah's heart failed.
She's on the transplant list,
but the way in which her heart APPEARS to be able to heal itself,
is something her doctors are banking on for her recovery.
In between her episodes of heart failure, she doesn't need anything.
And her own heart is... you know, it's the best device,
it's been perfectly designed and when it works well, it's a fantastic pump.
She's, you know, not had any trouble for a year or so,
and we certainly don't like to transplant people unless its absolutely necessary,
because a transplanted heart doesn't last for ever either
and brings with it a whole host of other issues that need to be looked after.
It's a big day for Hannah.
She's having tests to find out if she can come off the transplant list
and that's why everyone's a bit nervous.
Everything comes down to the results of this appointment.
So her scan test is good,
so the function has held up, basically.
So it's the sense of us in the unit,
that probably now is a good time to take her off the transplant list.
You know, her functions held up well for a year.
It's good news.
Hannah's heart function has improved significantly
and she's coming off the transplant list.
Well, it's fantastic to see her.
For Hannah's parents, today's results are everything they could have hoped for.
We're very pleased to hear what Doctor Kirk said
about Hannah's heart function.
It's been recovered and it's been doing really good.
And her name is off the heart transplant list, which is very... I mean, an important thing for us.
It is, it's a big relief.
We're obviously very, very pleased that her own heart has recovered,
recovered enough to come off the list.
A lot of people in your situation would be wanting, would perhaps be pushing for a heart transplant.
How do you feel about that?
From day one when she got ill, I would hope and pray
that her own heart would get better,
that always her own heart would get better, recover
and she keeps her own heart.
And I think even to this day, we would still do the same - we would hope and pray for that.
It must take enormous courage to be Hannah and her family
and to have endured what they've had to endure this past few years.
And you begin to realise that if you're going to make progress,
we're going to have to reinvent our concepts of the heart,
we're going to have to find new insight,
we're going to have to build an entirely new paradigm.
There is a new hope on the horizon,
one which everyone's hoping will be the fix-all to broken hearts.
Something which capitalises on this idea that the heart might be able to regenerate.
And in hospitals across the world, doctors and scientists are trying to harness these capabilities
and use them to change the way we mend broken hearts.
That new hope is stem cells.
They're kind of like the body's ultimate spare parts rack.
If your home had stem cells, it would be like being able to reach into your loft,
pull out a lump of plastic and mineral and give it a shake and, on demand,
have it turn into a television or a radio or a toaster
or anything else you'd broken and wanted to replace.
It's that property of renewal that scientists are hoping to exploit
and it's that that makes stem cells so important.
Peter Berry is a man who believes stem cells saved his life.
Before being treated with stem cells, he'd suffered two heart attacks,
leaving his heart irreversibly damaged.
Just tell me a bit about what life was like before you had the treatment.
It was pretty grim, actually.
You know, I was...
just basically, I was surviving and that was it.
If I'd overstretched myself a bit, you know, perhaps I'd done too much gardening,
I suddenly started to get out of breath,
if I'd go upstairs, I'd stop about four or five times when it really got bad,
to reach the top of the stairs.
Peter's heart function had been reduced to just 20%.
The only thing doctors could give him was medication, as he was too sick to survive a transplant.
But five years ago, he took part in a stem cell trial, which he's convinced gave him his life back.
After about seven weeks, I started to feel a lot better
and people said to me, you're beginning to look better,
you've got colour in your face, you're walking better,
I wasn't getting out of breath so much
and it just went on and on.
I can do me gardening, I do decorating, ride me bike round the marshes,
sometimes I'm over there two or three hours riding me bike.
I do most things.
It could be that Peter is one of the triumphs of the stem cell revolution.
I was keen to find out how the stem cells might have fixed his heart.
Peter took me to meet the man who led the trial,
Professor Anthony Mather.
Peter, you're a regular visitor to this hospital now.
Oh, yes. yes.
Professor Mather is trying to unlock the possibilities that many believe stem cells hold.
You're back here a couple of times a year? Yes.
He showed me what Peter's heart looked like before he'd received any stem cells.
So the purple-blue colour up here is normal,
so if you hadn't had a heart attack, this whole picture would be purple.
But in Peter's case, because he's had damage to his heart,
you can see red, and generally red is bad, and here it is too.
The area of interest for us is this green band around the red part,
which is an area that has got perhaps some degree of function but is not as it should be
and that's the target zone that we were injecting the cells into for Peter.
Peter was injected with stem cells from his own bone marrow and it's clear that his symptoms improved.
But his recovery could not be backed up with any traditional evidence.
Much to our surprise, we've seen some quite dramatic improvements in how people feel
such that the stories of how their life has been changed
simply being involved in the trial have been very dramatic,
but, interestingly, very little changes in the pumping action of the heart
and that's now making us reconsider whether measuring the pumping action of the heart
is actually the best way of working out
whether somebody is going to benefit from these new therapies.
Peters scans after the stem cell treatment showed no change in heart function.
So it's difficult to know precisely how the stem cells have worked.
It is, on the face of it, almost a little bit difficult to swallow.
You know, that the only...
We have a few crude ways to parameterise the heart,
and those measures don't obviously improve, but Peter in himself feels better, reports being better.
Absolutely.
The question is now, how has that happened and what is going on?
And so it opens up a whole new field of research.
But the benefit is that somebody has got better.
None of this is very neat,
and it's that state of perpetual uncertainty that has to exist
at the start of any phase of medical exploration, of medical research.
And that's where Mather and his team are at the moment.
They understand that from that initial hope
must follow many, many years of clinical trials
before they get an answer that becomes a therapy and makes everything better.
Stem cell therapy like this does appear to be doing something.
Whether we understand what or how remains unclear.
But the fact that Peter is a changed man
hints at their potential healing properties,
which people like Anthony Mather are seeking to understand.
The last stage in my quest to find a way of mending broken hearts takes me to Spain.
Because it's here that I think some of the most remarkable work with stem cells is going on.
And there's a good reason as to why it's happening in Spain.
It's the country with the highest rate of organ donation in the world.
Every single person you see around you, all of these people
are registered by the Spanish Government as potential organ donors.
And even here, there aren't enough hearts to go around.
But I've come to meet an American who's travelled all the way from Minnesota to Madrid,
because she might just have found a way to mend a broken heart.
The person I've come to meet is Dr Doris Taylor.
I think if anyone deserves to be called a pioneer in science, it's her.
Because she may have discovered a way of using stem cells to build a completely new heart.
She has a very different ambition as to how stem cells might be used.
Doris, we've been looking for a way to mend broken hearts,
and I wondered if you might be able to help us with that.
I hope so.
We've basically developed a way
that lets us take a heart from a cadaver,
drain all the cells, use the underlying scaffold,
transplant your own cells back in and rebuild the beating heart - it's amazing.
And build a new heart is precisely what she's done.
Doris realised that what she needed to make this happen was a framework to put the stem cells on.
You need a scaffold,
you need a place to put those cells so they know that they're a heart.
And so she started by taking a rat heart and removing all its cells.
Then she tried the same thing on a pig's heart.
And here is that scaffold.
The matrix that is left when you've removed all the cells from the heart.
And that we call our "ghost heart". It's beautiful.
And if you think that sounds a bit far-fetched, it isn't.
Even more incredibly, two years ago, she succeeded introduced stem cells to a rat heart scaffold
and made it beat again.
Now we'd like to think that we've opened a door
for building complex tissues and organs, and that the world of transplant may change as a result.
Now she's gone one step further.
She's trying the de-cellularisation process in human hearts with the same ambition.
So this is it. This is your lovely new lab.
When was it opened?
Two days ago, fabulous.
Doris is going to show me the technology that she's invented
to rebuild a human heart with stem cells.
This is our new cell culture laboratory.
It's a process which, for now, begins with a donor heart.
This is a heart that was actually harvested earlier this week.
It's a bit sobering to actually have the opportunity
to be holding a bowl with a human heart in it
and then think that we... somebody enabled us to move this technology forward.
This heart couldn't be transplanted,
but what we learn from it could change the world of transplantation.
This is really the first time
I've ever held a human heart in this context, in this way.
It's very difficult, really, to express how amazing it really is.
I... You know, that is a human heart
and...everything that it represents, really. Exactly.
I think it's quite incredible.
The first thing she has to do is create a ghost heart.
It's a process that involves hanging the heart in the best position possible
to be able to strip it of its own cells.
The idea is that we use the detergent here
to wash all the cells out of the heart.
And so where blood would have once run,
you actually now have detergent running, and that's just to dissolve the cells? Literally.
It takes just three days for the ghostly scaffold to emerge.
We've actually cut this heart to look at the inside,
and it's been in formalin,
but you can see the cells are gone but the structure is there.
That's just incredible,
and this is the dissected scaffold of the heart.
Scaffold of a human heart.
Very beautiful.
I don't think I ever anticipated that after you've got rid of all of the cells,
there's so much structure left.
We can put that back together and it essentially looks like a heart.
Yeah. This really does give you a scaffold on which you can work.
You can just see how that's going to be something that you can just stick cells back on top of.
And it's when stem cells are placed on the ghost heart
that their amazing potential for regeneration can be realised.
Wow. That's quite incredible.
The hope is that the scaffold will allow them to go on and make this heart beat again.
Doris, we know stem cells have magnificent potential, but how do they really know how to be a heart?
We think it's architecture.
If you think about it,
cells in a dish beat,
but that doesn't make a heart.
When we put them back in this scaffold,
they find themselves in the right place.
They're surrounded by the right things.
They know they're in a thin region, a thick region.
And we really think that to build an organ
is not just a combination of cells,
it's cells and architecture and physiology.
What is your ultimate goal in all...?
Where in all of this exploration do you hope to be at the end?
The thought would be that we would take a heart, probably from a pig,
do this process, wash all the cells out,
and then take your cells, and grow enough of them to repopulate this with your cells,
build a heart that matches your body
and have it transplanted into you, that's a home run.
If this works, it will be revolutionary.
It would mean that your broken heart could be replaced with a new heart
built using your own cells.
We should be clear about what we're looking at here -
this is the beautiful gift of a donated heart.
And even though it wasn't suitable for transplant, its journey doesn't end here.
It will go on in this laboratory to have its cells removed
and then to be repopulated with stem cells, and finally, it will eventually beat again.
And in advancing our understanding of the heart,
our understanding of how to build hearts, ironically,
it may not just save one life but go on to help to save millions.
The search for a way to mend a broken heart is the story of medicine.
It's about the war against disease, the incredible courage of individuals
and our search for a deeper understanding.
And everything I've seen makes this feel like a truly exciting time,
like we're on the cusp of something genuinely extraordinary.
Somewhere in all of this lies the answer.
That might be engineering, it might be stem cells, it might be computation.
But whatever it is, you can be sure that science and medicine
will run as hard and as fast as they can
till they find that thing that finally makes a difference for all of us.