Bone marrow cells improve heart after attack-study

By Bill Berkrot and Ransdell Pierson

DALLAS (Reuters) – Heart attack survivors whose hearts were
infused with stem cells from their own bone marrow showed
nearly twice the improvement in the organ’s pumping ability as
patients given a placebo, according to a new study presented on
Sunday.

A further analysis of the data found that benefits to heart
function seen four months after an attack appeared to be most
pronounced in patients with more severe heart attacks that
caused greater damage to the muscle, researchers said at the
American Heart Association annual scientific meeting.

“The medications and interventional therapies available so
far are intended only to limit further damage to the heart,”
said Andreas Zeiher, professor at J.W. Goethe University in
Frankfurt, Germany, and a senior author of the study.

“In contrast, progenitor cell therapy has the potential not
only to limit further damage, but to regenerate heart
function,” he said.

Progenitor cells are immature cells that can become a
variety of specialized cells.

“The concept that we can regrow heart muscle cells would be
an extraordinary development in the treatment of heart
disease,” said Dr. Richard Stein, director of preventive
cardiology at New York’s Beth Israel Hospital, who is attending
the meetings.

“It changes the entire game,” he said of the prevailing
thought that a person has a finite number of heart cells that
cannot be regrown once they are destroyed.

The primary goal of the 204-patient study was to show
improvement in function of the left ventricle — the pumping
chamber of the heart — which is considered a good gauge of a
patient’s prognosis following a heart attack.

Both groups in the study had nearly identical left
ventricular function going in, and both showed improvement
after four months as expected, researchers said.

But patients who received the bone marrow cell infusion saw
an improvement in their left ventricular ejection fraction — a
measure of heart efficiency — on average, of 5.5 percent.
Those getting placebo saw a 3 percent improvement.

Researchers said the compelling results stood in contrast
to “widely mixed results” seen in prior smaller studies of the
cell therapy.

They were further encouraged by other results, including
less heart enlargement seen in the bone marrow cell patients,
and improved blood flow in the artery where the attack
occurred, indicating the possibility that new blood vessels may
have been created to nourish the damaged area.

Heart enlargement, which often occurs after an attack as
the heart tries compensate for reduced pumping ability, is a
hallmark of a failing heart.

The reduction in heart enlargement seen in the bone marrow
cell patients appeared to lead to reduced incidence of new
heart attacks, hospitalization due to heart failure and deaths,
researchers said.

“The trial may be a landmark in helping to determine
whether the concept of progenitor (cell) therapy will have a
future for restoring heart function after” heart attacks, said
lead investigator Volker Schachinger of Goethe University.