An estimated one in 20 patients undergoing a common
operation to boost blood supply to the
heart and to ward off repeat heart attacks may do better if
their surgeons also remold the heart to a
near normal size, by cutting and suturing together
stretched muscle and scar tissue resulting from the
initial attack, according to cardiac surgeons at Johns
Hopkins.
In a study presented Jan. 28 at the 44th annual
meeting of the Society of Thoracic Surgeons in
Fort Lauderdale, Fla., the Johns Hopkins team found that in
patients with advanced heart failure, by
combining so-called coronary artery bypass grafting, known
as CABG, with surgical ventricular
restoration, or SVR, the likelihood of subsequent heart
problems was 24 percent, compared to 55
percent in those undergoing CABG alone.
"Cardiologists and cardiac surgeons with patients
about to undergo coronary bypass surgery
should clearly be considering ventricular restoration,"
said senior study investigator and cardiac
surgeon John Conte. A quarter-million Americans undergo
bypass surgery each year. "For those who
qualify for the dual procedure, the trend is clearly toward
living longer, with fewer hospitalizations
and improved quality of life."
Moreover, Conte says, the combined procedure in
patients with moderate heart failure offers
increased chance to delay or put off entirely the need for
a heart transplant. He points out that there
is a tremendous shortage of organs available for heart
transplantation, with nearly 3,000 Americans
currently on waiting lists.
Conte, an associate professor of surgery at the School
of Medicine and its
Heart Institute,
cautions that not all CABG patients can benefit from SVR
and that the procedure is most appropriate
for those with moderate to severe heart failure, whose
pumping function has dropped to less than 35
percent (with 65 percent being normal), and who have
suffered a clearly defined heart attack in the
heart's main pumping chamber, the left ventricle. "We
estimate that about one in 20 CABG patients
who have congestive heart failure are in this category,
from the volume of patients we see here at
Hopkins," Conte said.
The new study compared results for two groups of men
and women at Johns Hopkins, with
similar degrees of heart failure and medical histories. One
group of 62 had the dual procedure, and
another group of 58 had CABG only. All patients were
operated on between June 2002 and December
2005 and were monitored afterward by phone and regular
check-ups.
The study is believed to be the first head-to-head
comparison of the single and dual procedures
that applied strict scientific controls, using similar
patients in both groups and the same team of
surgeons to ensure a uniform quality of surgery.
Results showed that heart function improved for 80
percent of patients who had the
combination procedure and for 57 percent who had the single
procedure. Signs of progress included
being able to stay active, take walks and participate in
normal everyday activities, such as getting
dressed, without becoming exhausted and short of breath.
Death rates during surgery with either CABG alone or
CABG with SVR remained the same (at
5.2 percent and 6.4 percent, respectively) and measures of
pumping function, called the ejection
fraction, also improved by the same amount (at 32 percent
and 34 percent.) Researchers plan to
continue monitoring the study patients to better assess
long-term survival rates.
"Surgical ventricular restoration can be performed
with minimal training and by any cardiac
surgeon," said Conte, who has performed nearly 150 of the
dual procedures since 2000.
The add-on procedure, he says, takes a half hour
beyond the average two-hour, single CABG
surgery, in which arteries from other parts of the body are
transplanted to the heart in order to
increase its blood supply and to get around, or bypass,
arteries narrowed from disease.
In SVR, surgeons cut open the left ventricle and sew
it back together — without actually
removing any tissue — to more closely resemble a
smaller, normally shaped heart. Often, a patch is sewn
over the cut areas to hold the newly shaped heart
together.
"Remodeling the heart can restore the heart to its
normal, elliptical shape, lowering the
pressure buildup inside the heart cavity, reducing the
amount of oxygen and energy needed by the
muscle to keep pumping and allowing the heart to work
normally," said Conte, director of heart and
lung transplantation at Johns Hopkins.
Both CABG and SVR are covered by Medicare and by most
health insurance plans. Costs vary
according to how many arteries must be bypassed and what
other parts of the organ also need to be
shored up. The standard Medicare rate for a single CABG is
$1,800, with SVR costing an additional
$700.
According to researchers, stretched heart muscle and
scar tissue, known as ventricular dilation,
is a common consequence of heart attack. The heart dilates,
or thins out, in response to increasing
pressure within the heart, forcing it to work harder and
less efficiently to pump blood through the
body. A common result is heart valve leakage, which may
also require surgical repair.
The latest estimates from the American Heart
Association, in 2004, show that more than 5
million Americans are currently afflicted by heart failure,
with nearly three-quarters preceded by
high blood pressure. All are at greater risk of hypertrophy
and heart attack.
Study support was provided by funding from The Johns
Hopkins Hospital.
Other Johns Hopkins investigators in-volved in this
study were lead investigator Roni Prucz,
Eric Weiss, Nishant Patel, Lois Nwakanma and William
Baumgartner.