The Culture of Different MKTG_150064494_2018 Service Line Big Book Full_FIN | Page 36

The Future of Single
Ventricle Care Will
Be Engineered
Karla and Derick Senn got the
diagnosis at 20 weeks: Their
son, Jaden, had hypoplastic left
heart syndrome, or HLHS, a
rare and potentially devastating
congenital heart defect.
With his left ventricle atrophied,
only Jaden’s right ventricle
could pump blood — which,
as long as he was in the womb,
could circulate through his body
via the ductus arteriosus. Once
he was born, once he needed to
breathe, that would change.
He’d immediately need
intensive care. Within days,
he’d need a Norwood operation
to attach his aorta to his right
ventricle and shunt blood to the
lungs. Over the next two years,
he’d need two more major open
heart surgeries — the Glenn and
the Fontan — to fully harness
his one working ventricle to do
the job of two.
Karla and Derick were first-time
parents. They couldn’t wait to
meet their son. But as Karla’s
due date approached, their
anticipation mixed with fear.
“The last month was difficult,”
says Karla. “We were counting
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Pulmonology
Pediatric Surgery
Psychiatry
These polymers represent Dr.
Jacot’s basic canvas, produced
essentially by removing the
cells from an animal heart
and dissolving what’s left. This
“ghost heart matrix,” combined
with synthetic materials, is the
medium for his ultimate goal:
using stem cells to engineer
tissue that can seamlessly meld
with a living heart.
He’s surprisingly close to that
goal. For a kid like Jaden, it’s
feasible — even likely — that
tissue engineered in a lab like Dr.
Jacot’s will eventually become
a part of his heart. What part,
exactly, is hard to say.
Cardiology and
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that cells lay down,” says
Dr. Jacot. “Most of it’s collagen,
but there are a lot of other
materials that reinforce and
change its properties.”
Derick Senn and his son Jaden, who has hypoplastic left heart syndrome.
One day, doctors might use his stem cells to rebuild structures of his heart.
down to the time when our son
was no longer going to be safe.”
Building a surgical
patch that beats
At the Gates Center for
Regenerative Medicine, a
10-minute walk across the
Anschutz Medical Campus from
Children’s Hospital Colorado’s
main hospital, Jeff Jacot, PhD,
with the University of Colorado
Department of Bioengineering,
is figuring out what’s in a heart.
“Much of the material in organs
is made up not of cells but of
naturally occurring polymers
Currently, pediatric congenital
cardiothoracic surgeons
like Ja mes Jaggers, MD, Co-
Medical Director of the Heart
Institute, use synthetic patches
to reconstruct a variety of
malformed heart structures.
“We’ve all been frustrated
with the limitations of existing
materials,” Dr. Jaggers says.
“These patches are made of
either prosthetic or biologic
tissue foreign to the patient,
so the body reacts to them, and
they create scars and promote
clotting. And, because they
cannot grow, the child may
essentially outgrow them.”
As soon as five years from now,
Dr. Jacot says, doctors might
start the process of heart
engineering right at diagnosis
of a condition like HLHS. Then
and there, they could harvest
a patient’s own amniotic
stem cells, which a lab could
genetically manipulate to
revert to their embryonic stage.
They could then be induced
to develop into the variety of
cells that make up the heart:
myocardial cells that contract
and pump; endothelial cells
that line blood vessels; smooth
muscle cells that make them
dilate or contract; fibroblast
cells that maintain and repair
the tissue; nerve cells that tell
them all what to do.
Using a combination of
3D-printed synthetic materials
and electrospinning — in which
a positively-charged cellular
mix is drawn through a nozzle
toward a spinning, negatively-
charged surface — the team
could weave that matrix into a
patch, or even a structure like a
valve or an artery. A surgeon like
Dr. Jaggers, Dr. Jacot’s clinical
partner, could then implant
that structure to repair a defect
like HLHS. As the patient’s
heart beat, it would beat. As the
patient grew, it would grow.
All this technology already exists.
Dr. Jacot has already shown that
a patch made of heart matrix
outperforms synthetics in animal
models — and that, over time, the
heart’s existing cells will invade
the matrix, incorporating it into
tissue. The next step is to test a
patch with cells in place. That’s in
progress now.
In the meantime, Dr. Jacot says,
“We’re tuning in the right mix
of chemicals, environmental
factors, forces — anything that
will influence the structure and
development of heart tissue —
to allow these cells to function
the way they do in vivo.”
Life with a
single ventricle
Karla and Derick did their
homework. They asked their
specialists for outcomes
information, and when it
wasn’t forthcoming, they
shopped around.
“We walked into a meeting with
Children’s Colorado and they
handed us all their outcomes
for that year and the last five
years,” Karla recalls. “Walking
out to the car, we were like, ‘This
is where we’re supposed to be.’”
At Children’s Colorado, Jaden
would have a roughly 90 percent
chance of surviving the Norwood
— significantly better than the
85-percent national average. *
His chances rose to 99 percent
for the Glenn, and effectively 100
percent for the Fontan.
Now 3 years old, Jaden had the
Fontan last year.
“His energy levels are through
the roof,” Karla says. “He’s
barely stopped moving since.”
But the energy comes at a
price. Routing the body’s entire
blood-flow through the lungs
increases static pressure in the
circuit. Over time, that pressure
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