STANFORD, CALIF. (June 1) BW HEALTHWIRE -- When Dan Thorn learned
during a routine company physical that a valve on the left side
of his heart was leaking, at first he refused to believe it. After
all, the Menlo Park resident was in his early thirties and jogged
regularly, lifted weights and participated in martial arts. He
hardly fit the profile of someone who needed heart surgery.
Thorn's
youth and fitness weren't the only things about his case that
were unusual. To get the materials to correct the defective valve,
surgeons at UCSF Stanford Health Care went to an unlikely source:
the other side of Thorn's heart.
The
surgeons, led by Bruce Reitz, MD, chairman and professor of cardiothoracic
surgery at Stanford University School of Medicine, used the pulmonary
valve from the right side of Thorn's heart to replace the defective
aortic valve on the left side of the heart.
The pulmonary valve makes an ideal substitute, Reitz said, because
it is about the same size and shape as the aortic valve and is
able to close tightly even under high pressure. And the valve
is not rejected by the immune system because it is the patient's
own tissue.
The
aortic valve must form a solid seal to prevent blood from reversing
into the heart during contraction. Leakage can occur if the flaps
of the valve are congenitally malformed or are corroded by infections
or diseases like rheumatoid arthritis. For the patient, a faulty
aortic valve causes shortness of breath and fatigue because the
heart begins to fail due to the extra work load.
The
heart responds to the inadequate circulation by enlarging and
pumping harder, which over the long term weaken its muscle. If
not corrected, the condition can lead to heart failure and death.
Reitz
said the alternatives -- implantation of a mechanical valve or
one taken from a pig's heart -- give inferior results over time
because the immune system attacks the animal implants, and blood
clots may form on the mechanical ones. A pulmonary valve transplant,
however, can last the lifetime of the patient, Reitz said. To
replace the relocated pulmonary valve, surgeons implant a pulmonary
valve taken from the hospital's tissue bank of donated human valves.
Stanford
surgeons started regularly performing the procedure in 1993. They
now carry out 15 to 20 of the surgeries a year, more than any
other hospital in the Bay Area, Reitz said.
But the procedure is not really new. In the early 1960s, Stanford
heart-transplant pioneer Norman Shumway, MD, PhD, conceived of
using the pulmonary valve as a replacement for the aortic valve.
Shumway, who is now an emeritus professor of cardiothoracic surgery,
showed the procedure would work in dogs, but he never tried it
in humans. It became known as the Ross procedure after English
surgeon Donald Ross perfected the technique and proved it was
safe and effective for people.
Thorn
and his doctors decided the time had come for surgery when he
started to black out occasionally. "About a month or two before
the surgery, I started getting blackouts where you fade in and
out, almost like an elongated deja vu," he said. Thorn felt that
the Ross procedure offered the best chance of returning to normal.
He said that a mechanical valve is noisier than a natural valve,
and the sound of a mechanical valve slamming shut would constantly
remind him of his problem.
Thorn
only spent three days in the hospital after his April 1997 operation
and went back to work about two months later. He said he eased
into his athletic routine, but his recovery was slowed by knee
and ankle operations that were unrelated to his heart surgery.
"I should have my 'Your Fifth Surgery Is Free' card," he said.
Thorn has now resumed all of his pre-surgery activities.
"In
the two years I've had it, I would say it's better than my original
heart," he said.
Why
did the Ross procedure take so long to win converts? "It took
quite a few years for results to accrue and for people to see
the outcome," said Reitz. Initially, surgeons were hesitant to
try the operation because they thought it was more challenging
and had greater potential for side effects than standard valve
replacement, he said. However, heart surgeons throughout the world
are now performing the Ross procedure, he noted.
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