World-first partial heart transplant with ‘living tissue’ saves baby boy born with fused arteries

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A 5lb newborn boy with a life-threatening heart defect received a world-first partial heart transplant using living tissue that may never need to be replaced.

North Carolina child Owen Monroe, who is now four months old, was born with his two main arteries — the aorta and pulmonary artery — fused together in a condition called truncus arteriosus.

Doctors separated them and replaced ‘leaky’ heart valves shortly after birth using with living tissue that will grow with him, avoiding further surgery. In operations to repair fused valves, dead tissue is usually used — but it needs to be replaced in extensive surgery up to three times before adulthood, and every 10 years after that. 

Now four months on from the surgery at Duke University, North Carolina, the infant is ‘thriving’ and hitting every development milestone. 

His mother, Tayler Monroe, called the procedure a ‘miracle’ and said that it saved her son’s life. 

Truncus arteriosus is normally a death sentence for infants without surgery, as the heart over-works itself struggling to get nutrients to every corner of the body. It is also rare, with less than one in 10,000 American babies born with it.

Owen Monroe was born weighing 5lbs in North Carolina. His parents signed him up for the partial heart surgery after being told they would need to wait six months for the full transplant, which could be too long for their son

Owen Monroe was born weighing 5lbs in North Carolina. His parents signed him up for the partial heart surgery after being told they would need to wait six months for the full transplant, which could be too long for their son

Pictured above is the operation taking place, where Owen's fused arteries were separated and the valves in his heart replaced

Pictured above is the operation taking place, where Owen's fused arteries were separated and the valves in his heart replaced

Pictured above is the operation taking place, where Owen’s fused arteries were separated and the valves in his heart replaced

Pictured is Owen a few months after surgery, with the scar visible on his chest

Pictured is Owen a few months after surgery, with the scar visible on his chest

Pictured is Owen a few months after surgery, with the scar visible on his chest

Mother Tayler said it was 'miraculous' that her son had survived. He is 'thriving' and hitting every development milestone in line with his peers

Mother Tayler said it was 'miraculous' that her son had survived. He is 'thriving' and hitting every development milestone in line with his peers

Mother Tayler said it was ‘miraculous’ that her son had survived. He is ‘thriving’ and hitting every development milestone in line with his peers

A normal heart

A normal heart

Owen's heart which had truncus arteriosus, or where the aorta and pulmonary artery are fused

Owen's heart which had truncus arteriosus, or where the aorta and pulmonary artery are fused

NORMAL HEART AND OWEN’S HEART: Shown above is a normal heart (left) and Owen’s (right). He had a rare condition called truncus arteriosus. It is normally a death sentence without surgery

Parents Tayler and Nicholas Monroe said their son’s diagnosis left them with ‘few options’ as he was already likely to suffer heart failure shortly after birth.

They were told the waiting list for a full transplant was about six months, which their son was unlikely to reach.

So they signed up for the experimental surgery at Duke University, which would use living tissue to separate the fused arteries.

What is truncus arteriosus?

This rare defect is where the two main arteries to the heart — the aorta and pulmonary artery — become fused together.

The condition is normally a death sentence for infants without surgery.

But children typically need several operations over their lives to replace the valves as they grow — because these do not grow with them.

What are the symptoms?

These appear within the first week of life and include.

  • Bluish color of the lips and nails;
  • Fast breathing or trouble breathing;
  • Poor feeding. 

How is it treated?

Babies are quickly treated after they are born to avoid congestive heart failure, when the muscle stops working because it can’t pump enough blood to meet the body’s energy needs.

They are then offered surgery to separate the two arteries. 

What’s the survival rate? 

About 90 percent of infants who get surgery live longer than 40 years.

The condition is rare, with less than one in 10,000 American babies being diagnosed with it.

Source: Cincinnati Children’s Hospital

About 90 percent of infants who receive the surgery using tissue from a cadaver — the standard procedure — survive for more than 40 years.

But they will need at least three other operations in their lifetime to replace the tissue because they will grow, the American Heart Association says. It may also need to be replaced every ten years in adulthood.

When Owen was born doctors found that as well as having fused arteries he was also suffering from a ‘leaky’ heart valve — which would also need to be replaced. 

It is essential to have good heart valves as they stop blood flowing back in the wrong direction, interrupting circulation.

In the operation, he received living tissue and valves from another infant’s donor heart.

The heart had strong valves but was too weak to be used for a full transplant. Doctors said that without Owen’s operation it would not have been used.

After recovering and showing no ill-effects from the surgery, Owen was discharged and returned home.

Doctors say the youngster is now developing normally, and his parents could not be more thrilled.

Speaking before the birth, mother Tayler said: ‘It was basically like if something happened [at birth] we would resuscitate him and hope for the best, which is really hard  and scary to hear.

‘Nick and I had the conversation of is Owen here to be a donor for other babies, which is probably the hardest conversation you could ever have as a parent.’

But after the operation and her son’s recovery Tayler said it was ‘miraculous’.

‘The fact that not only he’s okay but he’s thriving really gives a lot of hope for future babies that have to go through this.

‘All of his doctors are thrilled at how he’s doing. He’s not behing at all developmentally, anything like that.’ 

Dr Joseph Turek, a cardiologist who led the surgery, said: ‘This procedure potentially solves the problem of a growing valve.

‘If we can eliminate the need for multiple open-heart surgeries every time a child outgrows an old valve, we could be extending the life of that child by potentially decades or more.’

In the surgery, doctors began by cutting the single blood vessel (pictured above)

In the surgery, doctors began by cutting the single blood vessel (pictured above)

In the surgery, doctors began by cutting the single blood vessel (pictured above)

They then used living tissue to replace the missing area of the aorta, and the missing area of the pulmonary artery. New valves were also added from the donor heart to control blood flow

They then used living tissue to replace the missing area of the aorta, and the missing area of the pulmonary artery. New valves were also added from the donor heart to control blood flow

They then used living tissue to replace the missing area of the aorta, and the missing area of the pulmonary artery. New valves were also added from the donor heart to control blood flow

Owen's heart has since functioned normally. Doctors hope that the living tissue will grow with him, avoiding the need for future heart surgeries

Owen's heart has since functioned normally. Doctors hope that the living tissue will grow with him, avoiding the need for future heart surgeries

Owen’s heart has since functioned normally. Doctors hope that the living tissue will grow with him, avoiding the need for future heart surgeries

Dr Michael Carboni, a cardiologist also at the university who consulted for the baby, added: ‘What’s particularly remarkable about this procedure, is that not only is this innovation something that can extend the lives of children, but it makes use of a donated heart that would otherwise not be transplantable.

‘The valves in this procedure come from a donor heart that had muslce tissue which was too weak to make it viable for a full transplant, but had strong valves that were well-suited for Owen’s needs.’

Father Mr Monroe said: ‘As harrowing  of an experience as it was for our family, we knew from the beginning that Owen was in the best hands.

‘Our greatest hope is that Owen’s success story will change the way organ donation and transplants are handled not only for congenital heart disease babies, but for all patients.’