Stem cells from fat win favor with heart researcher

CHICAGO (Reuters) – Stem cells derived from a patient’s bone marrow can help treat severe heart failure, but the results are even better when they are taken from fat, a leading researcher said, citing his experience in a number of studies.

“It’s no longer a question whether the bone marrow cells work or don’t work; they do work when you have healthy stem cells,” Dr. James Willerson of the Texas Heart Institute said in an interview. “The search now is to find the very best stem cell type or types.

“And at the moment, I’d say the best stem cells are fat-derived cells and stem cells that reside in the heart called c-KIT positive stem cells,” he said before presenting findings of his latest research at the annual scientific sessions of the American College of Cardiology in Chicago.

Willerson’s newest 92-patient, government-funded trial, is the largest study of bone marrow-derived stem cells ever done in patients with severe heart failure – a condition in which the heart is too weak to adequately supply the body with blood.

The study confirmed favorable results seen in the past decade from two of his previous studies of bone marrow-derived cells in similar patients, Willerson said.

He said patients enrolled in his latest trial called FOCUS had ejection fractions, a measure of the heart’s pumping strength, of 45 percent or less, far below normal readings of 55 percent or greater.

By removing stem cells from bone in the hip, growing them in culture and then injecting them directly into the heart, he said ejection fractions were nudged 2.7 percentage points higher.

“It was a small but statistically significant improvement and it was even greater if patients were younger,” he said, referring to those in their early 60s or younger, when stem cells are more functionally normal.

The patients will be followed for five years to assess the success of the treatment.

Although impressive, Willerson said the heart improvements in the FOCUS trial paled in comparison to favorable results seen in a recent study presented last year. They involved the use of fat-derived stem cells called mesenchymal cells to treat patients with severe heart failure.

In that trial, he said patients had improved heart function that actually translated into a reduction in death, heart attack, and the need for rehospitalization.

“They were more dynamic and impressive results,” he said, noting that patients with severe heart failure typically cannot walk any distance for lack of energy, are very short of breath and often sleep sitting up because they cannot breathe well laying down.

Willerson said he and his colleagues hope that continuing favorable trial results will convince U.S. health regulators that stem cells provide considerable benefit to heart patients and are safe.

“We’re very enthusiastic about stem cells in the repair of injured hearts,” he said. “There will be a day in the not-too-distant future that the U.S. Food and Drug Administration comes to believe the same thing.”

(Reporting By Debra Sherman; Editing by Paul Simao)

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Stem-Cell Trial Failed to Treat Heart Failure

SATURDAY, March 24 (HealthDay News) — An innovative approach using patients’ own bone marrow cells to treat chronic heart failure came up short in terms of effectiveness, researchers report.

Use of stem cell therapy to repair the slow, steady damage done to heart muscle and improve heart function is safe, but has not been shown to improve most measures of heart function, the study authors said.

“For the measures we paid most attention to, we saw no effect, there is no question about that,” said researcher Dr. Lemuel Moye, a professor of biostatistics at the University of Texas School of Public Health in Houston.

“Ultimately, this is going to pay off handsomely for individuals and for public health in general, but it’s going to take years of work,” Moye said. “We are the vanguard looking for new promising lines of research.”

While the hoped-for results didn’t materialize, there appeared to be a small improvement in some patients, he said. “When we looked at another commonly used measure of heart function called ejection fraction, or the strength of the heart’s pumping, that’s where all the action was,” Moye noted.

It’s hard to know which measures of heart function to look at, Moye explained. “We have had some difficulty with that,” he said.

Future research will look at other measures of heart function, pay more attention to the characteristics of the cells that are injected and determine which cells are best, he added.

Cardiac cells and other types of specially prepared cells are available now that were not accessible when this study started in 2009, Moye pointed out.

The results of the trial, which was sponsored by the U.S. National Heart, Lung, and Blood Institute, were to be presented Saturday at the American College of Cardiology’s annual meeting in Chicago. The report was also published online March 24 in the Journal of the American Medical Association.

For the study, Moye and colleagues worked with 92 patients, average age 63 and mostly male, who had heart failure with and without chest pain. They were randomly assigned to receive either an injection of 100 million bone marrow cells from their own bone marrow, or an inactive placebo. Patients in both groups also received aggressive medical therapy.

During the trial, the researchers looked for improvements in blood volume in the heart, oxygen use by the heart and blood flow through the heart.

After six months, the researchers said they saw no difference between the groups in these measures. Nor was any difference seen in the extent of heart damage, heart movement during contractions or overall condition.

Moye’s team did find a slight improvement in the heart’s ability to pump blood among patients 62 and younger. The improvement was small, only 3.1 percent, but patients in the placebo group declined 1.6 percent in this measure, they said.

It’s possible that cells of younger people are more potent, and that’s borne out by improvement in heart function seen in younger patients who did not get bone marrow cells, Moye said.

“We have demonstrated that the characteristics of the cells are correlated with heart function, so that the better the cells, the better the response — so even in patients who did not get stem cells, those younger patients did better,” he said.

Commenting on the study, Dr. Gregg Fonarow, director of the Ahmanson-University of California, Los Angeles, Cardiomyopathy Center, said there has been “tremendous interest in cell-based therapies” to treat acute and chronic heart disease and chronic heart failure.

Most studies trying delivery of different types of cells have been small and not adequately powered to demonstrate improvement in cardiac function or clinical outcomes, and results have been mixed, Fonarow said.

“While this study failed to meet any of its primary or secondary endpoints, the insights provided will be helpful in designing future trials,” Fonarow added. “However, whether cell-based therapies will be of therapeutic value to patients with heart disease and heart failure remains to be seen.”

More information

For more information on heart disease, visit the American Heart Association.

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Stem cell therapy could repair some heart damage

Patients with advanced heart disease who received an experimental stem cell therapy showed slight improvements in blood pumping but no change in most of their symptoms, US researchers said Saturday.

Study authors described the trial as the largest to date to examine stem cell therapy as a route to repairing the heart in patients with chronic ischemic heart disease and left ventricular dysfunction.

Previous studies have established that the approach is safe in human patients, but none had examined how well it worked on a variety of heart ailments.

The clinical trial involved 92 patients, with an average age of 63, who were picked at random to get either a placebo or a series of injections of their own stem cells, taken from their bone marrow, into damaged areas of their hearts.

The patients — 82 of whom were men — all had chronic heart disease, along with either heart failure or angina or both, and their left ventricles were pumping at less than 45 percent of capacity.

None of the participants in the study were eligible for revascularization surgery, such as coronary bypass to restore blood flow, because their heart disease was so advanced.

Those who received the stem cell therapy saw a small but significant boost in the heart’s ability to pump blood, measuring the increase from the heart’s main pumping chamber at 2.7 percent more than placebo patients.

The treatment worked best in the youngest patients, those under 62, according to the analysis which was done after six months of treatment.

However, other factors showed no improvement — the heart’s maximum oxygen consumption did not change and the defects in the heart were not healed by the treatment — according to an analysis of the study in the Journal of the American Medical Association.

“This is the kind of information we need in order to move forward with the clinical use of stem cell therapy,” said lead investigator Emerson Perin, director of clinical research for cardiovascular medicine at the Texas Heart Institute.

Perin’s research, which was conducted between 2009 and 2011 across five US sites, was presented at the annual American College of Cardiology Conference in Chicago.

The technique involved taking bone marrow samples from the patients and processing the marrow to extract stem cells. Doctors then injected the cells via catheter into the heart’s left ventricle.

The injections, comprising some 100 million stem cells in all, were specifically targeted at damaged areas, identified by real-time electromechanical mapping of the heart.

“With this mapping procedure, we have a roadmap to the heart muscle,” said Perin in a statement released ahead of the presentation in Chicago.

“We’re very careful about where we inject the cells; electromechanical mapping allows us to target the cell injections to viable areas of the heart,” he added, describing the procedure as “relatively quick and painless.”

Heart disease is the leading killer in the United States, claiming nearly 600,000 lives per year, according to the US Centers for Disease Control and Prevention.

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