Using A Patient's Own Bone Marrow Cells Can Help An Ailing Heart

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Using A Patient’s Own Bone Marrow Cells Can Help

An Ailing Heart

ANAHEIM, Calif., Nov. 12 – In the first study of

its kind, researchers have used a person’s own

bone marrow cells to improve blood flow in

otherwise untreatable coronary arteries, according

to research presented today at the American Heart

Association’s Scientific Sessions 2001 conference.

Kimikazu Hamano, M.D., and his colleagues reported

results from an ongoing clinical trial in which

five patients received injections of their own

bone marrow cells into oxygen-starved areas of

their hearts. Three of these patients later had

increased blood flow in these areas. " We found

this new treatment to be safe, and we believe it

could be an alternative treatment for heart

patients who cannot be helped by coronary artery

bypass surgery or balloon angioplasty, " says

Hamano, a lecturer at the Yamaguchi University

School of Medicine in Ube, Japan. Bypass surgery

and angioplasty can improve blood flow to the

hearts of many patients whose coronary arteries

are clogged and narrowed by fatty deposits. But

others cannot be helped at all or portions of

their heart cannot benefit from the procedures.

This is often because their heart disease is too

widespread.

Injecting adult stem cells from the patient’s own

bone marrow is easy, relatively inexpensive and

appears to have no side effects, Hamano says. Stem

cells are basic building block cells that can grow

into specialized cells in the body, such as heart

cells, nerve cells and organ cells. The Japanese

team began their human trial after a series of

animal experiments. The first patient was injected

with his own bone marrow cells in November 1999.

" We have good results from these experiments in

animal studies, " Hamano says. " The aim of the

current trial is to confirm the safety and

efficacy of this treatment in humans. " He and his

colleagues selected their study participants from

among patients who were scheduled to undergo

bypass surgery. Their five patients had an average

age of 66 and all suffered severe and debilitating

chest pain (angina). They were chosen because

areas of their heart muscle could not receive any

benefit from the bypass surgery.

As surgeons began bypass surgery on each

participant, the researchers withdrew bone marrow

from the patient’s hip bone. From this harvested

marrow, they prepared a mixture rich in

mononuclear cells, which includes immature cells

such as stem cells and the precursor cells of the

endothelial cells that line the inner walls of

blood vessels.

Depending on the size of the area of heart muscle

treated, the patients received between five and 22

injections of cells into the heart muscle,

administered 1 centimeter (0.39 inch) apart. The

patients were examined one month after their

injections/operations using a nuclear medicine

test called cardiac scintigraphy. Scintigraphy

measures coronary perfusion, which is the amount

of blood flowing to the heart. All of the patients

have been followed for at least one year.

Three of the five patients showed marked

improvement in blood flow to the parts of their

heart treated with bone marrow. Their severe chest

pain also had disappeared. The other two patients,

however, had no change in blood flow compared to

preoperative tests. Chest X-rays, blood tests,

electrocardiography, and ultrasound studies did

not reveal any detrimental changes in any

patients.

Despite evidence in three patients of increased

blood flow in the treated areas, “It was difficult

to clearly identify new vessels formed by this

treatment on postoperative angiograms,” Hamano

says. Angiography uses a combination of X-rays and

a dye injected into the heart’s arteries to

visualize the organ’s blood vessels. However, this

failure to detect new vessels did not surprise the

researchers.

" From our experimental data, the new vessels

formed as the result of bone marrow cell

injections were only 30 to 60 micrometers (about

0.00117 to 0.00234 inch) in diameter, " Hamano

explains. " The detection level of blood vessels by

angiography is more than 200 micrometers.

Therefore, it is understandable that we could not

see the new vessels. "

The important finding, he says, is the evidence of

greater blood flow to the heart muscle. Hamano and

his colleagues have now treated a sixth patient as

part of their continuing study. Co-authors are:

Masahiko Nishida, M.D.; Ken Hirata, M.D.; Akihito

Mikamo, M.D., Ph.D.; Tao-Sheng Li, M.D., Ph.D.;

Kensuke Esato, M.D., Ph.D.; Masahiko Harada, M.D.,

Ph.D.; and Toshiro Miura, M.D., Ph.D.