When Brailey and Louis Valenzuela learned they were expecting their second child, a baby girl, they were overjoyed.
They picked out a name – Arley – and enjoyed an ‘easy pregnancy’ for about six months.
However, an ultrasound at 24 weeks revealed a potentially deadly complication: baby Arley had an olive-sized tumor on her heart known as pericardial teratoma.
They were informed the tumor would kill her if left untreated, growing so big it would crush her heart under its weight.
Delivering Arley at that point would risk her life. At 24 weeks, her organs were still developing, and her odds of surviving outside the womb were low, so the Tennessee mother was referred to a team of specialists in Pennsylvania who have pioneered a procedure that allows them to operate on the baby while it is still inside her mother to remove the mass on her heart.
During surgery to remove the mass, doctors cut into the mother’s stomach and partially pulled Arley from her mother’s uterus , arms-first, so that her chest was exposed.
They always try to keep as much of the baby inside the mother as possible to maintain the protective environment that the uterus provides.
With the baby in that position, they were able to make an incision in her chest.
Arley recently saw her local cardiologist and is doing so well that she doesn’t need to return for another year
The doctors partially removed Arley from her mother’s womb by piercing the amniotic sac but did not fully birth her, keeping her protected in the fluid. Specialized devices maintained amniotic fluid levels to minimize risks, preventing the uterus or placenta from reacting to the surgery
Then, they removed the tumor located within the membrane surrounding the heart.
After the surgery, both mother and fetus are monitored closely for signs of recovery and to detect any potential complications.
Mrs Valenzuela told Today.com that she was in the Children’s Hospital of Philadelphia (CHOP), where doctors removed the tumor, for about two months until her daughter was born healthy and happy.
Pericardial teratoma in fetuses is deadly. A third of cases result in the death of the fetus.
The condition is rare, occurring in about 0.07 to 2.8 in 1,000 pregnancies. From 2000-2020, only 55 fetal pericardial teratomas were reported worldwide.
CHOP has performed the procedure to remove it in utero on four babies. Exact statistics on the number performed annually in the US are difficult to pinpoint.
They’re so uncommon and typically performed at centers with doctors with fetal surgery expertise, which makes tracking the exact number of procedures performed every year difficult.
All told, the procedure took about an hour. It was a team effort, including specialists from cardiology, fetal surgery, maternal-fetal medicine, cardiovascular surgery, anesthesiology, neonatology, and psychology as well as a special cohort of fetal nurses.
Brailey Valenzuela, 32, did not suspect anything was amiss with her pregnancy. She and her husband were excited to meet their second daughter.
But the 24-week ultrasound changed everything.
Doctors at Covenant Health’s Fort Sanders Perinatal Center in Knoxville confirmed that there was a tumor on their daughter’s heart.
Mrs Valenzuela said: ‘We were told multiple times the outlook is grim and if you don’t do something soon — in a matter of days — the baby could die.’
A cardiologist in Tennessee sent Mrs Valenzuela’s medical records to the Children’s Hospital of Philadelphia, where doctors often treat complicated and life-threatening pregnancies.
‘It was so fast,” Brailey Valenzuela said.
‘They said, “The physicians have looked over your file, and they think they can help you.” It was a huge relief.”
When they arrived in Philadelphia in December 2023, doctors had to act quickly, conducting a battery of tests, including additional ultrasounds.
Within 12 hours, Mrs Valenzuela was in surgery.
Dr Jack Rychik, one of the doctors involved in Brailey Valenzuela’s surgery, said fetal tumors like this one are ‘quite rare.’
The tumor, if left unchecked, could grow so large that it crushes Arley’s heart, which would kill her
He said: ‘It is a tumor that is growing wildly because very very young cells … are misbehaving. [They] could have turned into different organs but remain immature and decide to grow on their own.
‘The concern about the pericardial teratoma is that it is growing rapidly and uncontrollably in a space that’s very confined.’
The doctors partially removed Arley from her mother’s womb by piercing the amniotic sac, but never birthed her completely, meaning she was never exposed to air and protected mainly by the fluid there. Surgeons say one of their main objectives, apart from removing the tumor, is disturbing the surrounding tissues as little as possible.
Doctors used specialized devices to keep levels of amniotic fluid in the uterus stable, minimizing the risk of the uterus or placenta ‘sensing’ the surgery.
When Brailey and Louis Valenzuela of Knoxville, Tennessee , learned they were expecting their second child, a baby girl, they were overjoyed. But an ultrasound at 24 weeks revealed their baby had an olive-sized tumor on her heart
The body might naturally induce labor in response to disruptions, but these devices, along with anesthesia techniques, help prevent contractions, labor, or changes in blood flow by ensuring the uterus maintains its shape and fluid levels during the procedure.
Without intervening when they did, the mass on Arley’s heart could have grown so large, perhaps two to four times bigger than the heart, and pressed against it, preventing it from filling with blood.
Dr Rychik said: ‘You cannot survive with the heart not being able to fill. So that’s what makes these tumors lethal.’
Arley weighed just 1.8 pounds while this was happening.
Arley was born at 35 weeks, which is considered pre-term. But the surgery was a great success. Heart heart functioned normally
Mrs Valenzuela gave birth via c-section in February 2024. Doctors discovered her uterine lining was very thin and could rupture if they did not deliver Arley right then
As they removed the tumor, surgeons saw that it was slightly attached to the aorta, the largest artery in the body that carries oxygen-rich blood from the heart to the rest of the body.
After removing the tumor and repairing the tear left on the aorta, doctors stitched Arley back up, returned her to her mother’s uterus, and closed Brailey’s abdomen.
When she awoke, Mrs Valenzuela searched for her husband and pointed groggily to her belly as if to ask whether Arley survived.
She said: ‘I remember him saying, “The baby is fine. The baby is fine.” That’s all I needed to hear … it was a huge blessing.’
Arley is healthy and happy. Her mother says her heart functions like any other baby’s
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Within a matter of days, Arley’s heart began to function normally. All the while, Mrs Valenzuela stayed in Philadelphia, where she was under strict monitoring until she gave birth. When, on February 17, 2024, she began experiencing severe abdominal pain, doctors discovered her uterine lining was very thin.
To prevent a rupture, they delivered Arley via c-section at 35 weeks, which is considered pre-term.
Mrs Valenzuela said: ‘Her heart was great. It’s functioning like any other baby.’
Arley recently saw her local cardiologist and is doing so well that she doesn’t need to return for another year.
‘She’s doing great,’ Mrs Valenzuela said.
‘I hope people can have hope when they read Arley’s story.’
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