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When Georgia Bowen was born with an emergency Caesarean section on May 18, she breathed, raised her arms, cried twice, and had cardiac arrest.
The baby had already had a heart attack, most likely still in the womb. His heart was deeply damaged. much of the muscle was dead, or nearly so, causing cardiac arrest.
The doctors kept her alive thanks to a complex machine that fulfilled the function of her heart and lungs. Then they decided to try an experimental procedure that had never been tried before in a human after a heart attack.
They removed a billion mitochondria – the energy plants in each cell – from a fragment of Georgia's healthy muscle, and introduced them into the damaged muscle of their hearts.
Mitochondria are the first part of the cell that dies when it does not receive oxygen-rich blood. When they are lost, the cell dies.
However, a number of experiments have shown that fresh mitochondria can revive weakened cells and allow them to recover quickly.
In animal studies, mitochondrial grafts apparently restore heart muscle after an infarct, which is still alive, and revive damaged lungs and kidneys.
In human-only tests, mitochondrial grafts apparently repair damaged heart muscle in neonates during conbad heart defects repair operations.
But in the case of Georgia, the transplant was a shot in the dark – a heart attack is different from a temporary blood loss during an operation. There is a very short period of time between the beginning of the infarct and the development of a scar where there were previously living cells.
The problem was that no one knew when the infarction had occurred in the child. However, said Dr. Sitaram Emani, a pediatric cardiac surgeon who performed the transplant, had little risk for the baby and there was a chance that some cells could still be saved.
"They gave the child the opportunity to fight," said Kate Bowen, the girl's mother.
The idea of mitochondrial grafting arose out of despair and the happy encounter of two researchers from two Harvard hospitals. Emani of Boston Children, and James McCully of Beth Israel Deaconess Medical Center.
Dr. Emani, a pediatric surgeon, and dr. McCully, a scientist who studies the hearts of adults, has struggled with the same problem: how to save hearts that have run out of oxygen during surgery or a heart attack.
"If you cut the oxygen too long, the heart can barely pulse," said Dr. McCully. The cells can survive, but they will never fully recover.
Working with pigs, dr. McCully removed a small piece of the abdominal muscle and isolated the mitochondria. He injected them into the heart cells, and to his surprise, they headed to the right place in the cells and started providing energy. The hearts of the pigs have recovered.
Meanwhile, dr. Emani faced the same difficulties in her work with the heart of babies.
Many of your patients are newborns who need surgery to heal the heart malformations that threaten their lives. Sometimes, during or after one of these operations, a small blood vessel bends or crashes.
The heart still works, but the cells that run out of oxygen are beating slowly and weakly.
He linked the baby to a machine like the one that kept Georgia Bowen alive, for what is called extracorporeal membrane oxygenation, Ecmo. However, it is a palliative measure. Half of babies with coronary problems who end up in an Ecmo machine die.
But one day, they said to dr. Emani from dr. McCully. The two researchers met and treated 11 babies with mitochondria. All but one could come out of Ecmo, said Dr. Emani. However, three of them died later, and dr. Emani attributes his death to a delay in treatment and other causes.
In comparison, the mortality rate among a similar group of infants who did not receive a mitochondrial transplant was 65%. And none of the children who did not receive the treatment found any function of their heart.
The researchers intend to perform a test to see if mitochondrial grafts can repair heart muscle damaged during heart attacks in adults.
For Georgia, the procedure arrived too late. The part of his heart muscle affected by the infarction is dead. Their doctors have implanted a device that performs the pumping function of the heart, and they expect their heart to recover enough so that they can remove the device.
"Georgia is a miracle that continues to struggle daily and perseveres despite the obstacles it encounters," said the mother.
"In our hearts, we know that she will leave this and return home."
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