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>> You know, there are literally hundreds of experiments taking place
on board the International Space Station,
each and every expedition while the astronauts and the cosmonauts are up there.
One of the most important lessons
that the International Space Station is teaching us is how the human body actually reacts
to being up there for up to six months.
When we take a look at going to Mars, or going to an asteroid, or those longer type missions,
how our bodies react to those types of journeys is going to be incredibly important.
We're here at the cardio -- cardiovascular lab here at the Johnson Space Center.
I'm joined by Stuart Lee, who is one of the lead scientists for this laboratory.
Stuart, let's talk a little bit about first of all what this lab does,
and then we'll take a look at some of these machines back behind us.
>> Stuart Lee: So the main objective of this laboratory of course is to look
at how the cardiovascular system in particular responds to the effects
of lack of gravity or weightlessness.
We're involved in several studies.
One of the most important ones we're doing right now is an integrative cardiovascular experiment.
And the cardiovascular experiment, or ICV, is a multi-center study headed
up by Doctor Ben Levine at UT Southwestern, and Doctor Mike Bungo at UTL Sciences Center,
in collaboration with Johnson Space Center, and with the Cleveland Clinic
to give a good comprehensive evaluation of what happens to the heart in particular
as a result of being in weightlessness.
>> So let's talk about it real basically.
The heart's a muscle.
>> Stuart Lee: Yes.
>> Muscles react kind of strangely to being up in space,
we're still learning kind of what happens.
>> Stuart Lee: Right.
>> So talk about kind of what we've learned about how the heart and the rest
of the muscles react of what this ICD actually looks at and how it works.
>> Stuart Lee: So everybody probably has heard about muscle wasting or atrophy that happens
in the skeletal muscles in your -- particularly in your legs, and also in your arms.
Same sort of thing happens to the heart.
Most people don't realize that their blood actually has weight to it,
and your cardiovascular system has to work in order to get blood from your bottom part
of your body back up to your heart, and particularly to your brain.
>> 'Cause of the gravity.
>> Stuart Lee: Because of gravity.
>> Okay.
>> Stuart Lee: Exactly.
And so what we're looking at is because you lose those gravitational forces,
it actually has an effect on the heart.
The heart actually can get smaller as a result of not having to work as hard in space,
so that's called cardiac atrophy.
And what we're doing is looking at not just what happens
with cardiac atrophy during a space flight, but how it affects other things
that you would normally do -- your blood pressure regulation when you're standing up,
the exercise that you would normally do, or in the case of an astronaut the EVAs that they have
to do, as well as just a general function of the heart,
and the electrical conduction through the heart.
>> Okay. So let's talk about how you measure it.
What the -- what is the [inaudible]?
We've got these two machines here which are ultrasound machines, right?
>> Stuart Lee: Right, yeah.
>> Okay, so let's talk about them.
>> Stuart Lee: So what we do normally is we look at --
the first thing we want to do is look at the function and the size of the heart.
>> Uh-huh.
>> Stuart Lee: The way that you would do that scientifically is you'd use MRI.
The other way that you can do it in an ultrasound scan.
The ultrasound scan has the -- the -- the -- the ability to have that device on orbit,
and so we do measurements of the heart pre and -- and -- and post-flight using the ultrasound.
And you can see this is an image of the heart -- actually some images that we captured early --
>> Mm-hmm.
>> Stuart Lee: -- showing how the different ventricles
of the heart, and then -- and the atrium.
And so how blood flows through there, and then how the -- the heart actually contracts.
>> So this is actually what the crew member would see [inaudible].
>> Stuart Lee: This is what we would collect on the ground.
One of the neatest parts of this experiment is that we actually collect the data on orbit.
And rather than have the astronauts become experts in --
in stenography, we have one of our experts, Doctor --
Mister David Martin, who actually guides them on orbit, how to do the ultrasound on orbit.
And this is the device that we use for that.
>> This is the actual machine that's up there.
>> Stuart Lee: So there -- there's one just like this on orbit.
And what -- what David can do is he can then tell them where to place the probe,
how to angle it -- 'cause those are all very important things.
And then he teaches them, tells them how to -- what buttons to push in order to get the images
that they -- that they need for the experiment.
So that he's sitting in mission control, he sees the images they see,
and he also sees them doing the work.
>> So it's not like they have to become a PhD or an MD to -- to --
>> Stuart Lee: Right, yeah.
>> -- machine.
They just take some basic training, and then the -- the --
the ground teams can really kind of guide them through --
>> Stuart Lee: Right.
>> -- you know.
Now talk about [inaudible] kind's of interesting,
because our astronauts are incredibly smart people, but we miss color coding.
Talk about -- about it.
It makes it a little bit easier for them basically know which button to push.
>> Stuart Lee: Right.
So, you know, there's lots of different buttons on here,
and they've got all their own little labels on it, and it means a lot to the stenographers,
the people who normally do this stuff, but it doesn't necessarily mean a lot to, you know,
an astronaut who hasn't had as much training.
So David could say, you know, push pink number 2 --
>> Mm-hmm.
>> Stuart Lee: -- and -- and that -- they would know exactly where to go to it.
This is a template specifically designed for this purpose by NASA
to be able to do this sort of stuff.
One of the neat earth applications of this is that if you're in a remote environment
and you needed ultrasound, you could actually have a non-expert collect ultrasound
in the same fashion that David or -- or someone like him could guide them through the procedure,
and -- and do a diagnosis where there is no doctor.
>> Yeah. So you could just -- this has applications here on earth --
>> Stuart Lee: Yeah.
>> You know, you're not physically there with your doctor, somebody telling you what to do --
>> Stuart Lee: Yeah.
>> But you can actually kind of sort of -- I think I could probably even figure this out.
[ Laughter ]
>> Stuart Lee: It's a neat little system.
>> So talk about, you know, this ICV experiment, what -- what have we learned about the heart?
And -- and -- and you know, you said it gets smaller,
but how do you -- how do you combat that?
Like what -- what would you do to --
>> Stuart Lee: Well, the best way that we know how,
and the way we're doing it now is with exercise.
And so exercise on the ground makes muscles grow, it also helps the heart as well.
And so we do the same sort of thing on orbit.
The astronauts participate in treadmill exercise, and cycling exercises,
as well as weight lifting type exercises.
And all those sorts of things are good for the human body.
What we've learned so far is kind of interesting,
but we expect there's a certain amount of individual variability among astronauts.
Some people lose more, some people lose less.
What's pretty cool about the preliminary data so far suggests is that the amount of exercise
or -- or work, you know, cardiac work that your heart does
on orbit is actually related to the amount of atrophy we see.
So somebody who does a little more loses less of their cardiac mass, and people who end
up doing less than they would normally do on the ground would lose more.
>> So there's a direct correlation between --
>> Stuart Lee: Yes.
>> -- basically how much --
>> Stuart Lee: So far.
>> That's fascinating.
>> Stuart Lee: Yeah.
The study is about halfway through so we're still learning a lot,
so I don't want to put too much --
>> Yeah.
>> Stuart Lee: -- stock in that.
>> It's being going on for three -- three years, is that what you said?
>> Stuart Lee: Three years.
We've got three crew members on orbit right now, and we've got a couple more after that.
We should be done in the next couple of years, and we should be able
to start disseminating results at that point.
>> How often do they -- do they do this [inaudible].
I mean they're very busy up there, so how often do they actually, you --
you know, work with this type of experiment?
How often do they participate in it?
>> Stuart Lee: So we have a couple data -- or several data collections before flight,
so we get an idea of what their heart looks like and how it functions on the ground,
as well as we get an idea of -- of the amount of work
that the heart does using what's called ambulatory monitoring, where we --
we measure blood pressure and heart rate throughout 48 hours.
We get a baseline of what they normally do their typical day,
and then we repeat that five times on orbit.
So early in the mission, all the way to the end of the mission we'll repeat those measurements
of stenography, and then the cardiac work measurements.
The stenography, you know, takes about half an hour, 45 minutes to do the measurements.
We do it both at rest and during exercise.
And then the -- the other stuff that we call ambulatory monitoring, where they wear the --
it's an EKG and blood pressure monitor, that they wear --
wear for 48 hours, and it doesn't really interfere with their day per se.
So they're able to do their normal activities, 'cause what we're trying
to capture is what they normally do.
>> That's fascinating.
It's interesting that we're still learning about the human body and how it --
how it behaves up there, 'cause it is -- it's quite different.
>> Stuart Lee: Right.
There's a -- there's a lot to learn, and -- and everybody is different.
And we're trying to figure out what the best counter measures are to get us to Mars, and --
and to other planetary surfaces so we can learn more about our solar system.
>> Thanks a lot, Stuart.
>> Stuart Lee: Thank you.
>> We'll be back in just a few minutes, and we'll be talking about
yet another experiment that's going to be on board the space station that the crew is going
to be participating in in the future that uses this same type of equipment,
and talk about what the purpose of that is.
We'll be back in a few minutes.