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A
13-month-old boy has become the first person in the
United States to have a valve taken from a cow's neck
transplanted in his heart, officials said. Ryan
Doty has been breathing on his own since
Thursday night and the prognosis looks good, said Dr.
John Brown, the cardiothorasic surgeon who performed the
transplant May 4, 1999. The procedure, performed at Riley
Hospital for Children in Indianapolis, has not been
approved in the United States, but the Food and Drug
Administration permitted the surgery as a ``compassionate
case'' because of Ryan's critical condition. ``He was
extremely ill and really wasn't expected to live. This
was the only thing that could save his life,'' Brown, the
director of heart transplantation surgery at the Indiana
University medical centers, told The Evansville Courier
& Press in Sunday's editions. Ryan was in fair
condition this morning in Riley's intensive care unit. He
was born with only one heart valve instead of two. When
he was 3 months old, he received a heart-valve transplant
from an infant who had died. But that valve weakened and
developed leaks, said Brown, who performed the initial
transplant. Brown said there is always a critically short
supply of donor infant valves, and they tend to fail in
transplant procedures. In addition, pig valves used for
transplant in adult hearts are too large for infants. A
valve from a cow's neck ``is perfect'' for transplanting
into an infant's heart, Brown said. ``It has all the
qualities and properties that heart surgeons have been
looking for a long time,'' he told the newspaper. ``It's
strong, it's the right size, it has all the surrounding
tissue you need to make the hookup to the heart, and it's
less likely to have complications.'' The valve is treated
with chemicals so that the human body won't reject it.
When transplanted, ``it's not really living cow tissue
inside the patient,'' Brown said. The use of cow neck
valves in infants was approved in Europe a year ago,
Brown said. So far 13 of the transplants have been
performed in Switzerland and Italy, with successful
results. Eventually, infant patients will outgrow the
small valve, because it won't grow with them. Brown said
that when recipients become teen-agers, they'll require
another surgery to receive a pig's valve transplant.
Brown said he expects the FDA will approve bovine neck
valve use in America by the end of this year. Back
to Medical Wonders
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