Scientists have announced that they have been able to use stem cells to treat patients with heart failure, some of the first evidence that the much-hyped therapy could have significant clinical benefits.
In two studies reported at the American College of Cardiology conference, scientists used adult stem cells -- not the more controversial embryonic stem cells -- to treat patients and saw marked improvement in their health. Experts note these early studies need to be replicated in larger groups to confirm the results.
The findings are welcome news for patients like Joseph Glasser, 74, who received a bleak prognosis nine years ago after suffering a heart attack that left his heart so weakened he had to have a pacemaker implanted. Seventy-five percent of his heart muscle had died, his cardiologist told him, and there was nothing more he could do.
In the years afterward, Glasser frequently felt fatigued and short of breath, so he sought out new treatment options and eventually enrolled in a stem cell study at the University of California San Diego. There, doctors took cells from his leg, cultivated them in a lab and then injected them into his heart.
Today, two years after treatment, he says he no longer has problems maintaining energy, and even walks on a treadmill and swims.
"My ejection fraction went up. My heart reduced a little in size," he said, "but I don't need any numbers or proof that I am doing great. I have my body to tell me. I feel excellent, and I can do whatever I want to do."
He insists the procedure added years to his life. "My first cardiologist said he couldn't do anything for me and I would only live for five years, and now it is nine years later."
The study's leader, Nabil Dib, director of clinical cardiovascular cell therapy at the University of California San Diego, said one of the most notable aspects of the treatment was how minimally invasive it was -- patients don't even require anesthesia.
"We can do it with a catheter so they are awake during the procedure and can go home within 24 hours," he said.
That kind of targeted therapy is particularly valuable for high-risk patients like Glasser, who might be excluded from general surgery.
In the study, Dib and his colleagues extracted stem cells from the thigh muscles of 23 patients who, like Glasser, had poor heart function or heart failure. They then grew the cells in a lab and delivered them directly to patients' hearts through a catheter.
After six months, patients who had received the treatment showed improvements in health and quality of life, while those who had standard medical therapies worsened.
In a second study done at 10 medical institutions, researchers took muscle stem cells from donors, not the patients themselves, and infused them intravenously into cardiac patients within 10 days of a heart attack.
The researchers found that after six months patients had fewer side effects than those who had not received stem cells, and that they also showed improved heart and lung function.
"There was a lot of concern in the medical community about whether taking cells from an unrelated donor would cause a rejection reaction or cause tumors," said Joshua M. Hare, chief of cardiology and director of the Stem Cell Institute at the University of Miami School of Medicine.