Stem Cells May Help Painful Heart Condition
Published February 2007
UC physicians are participating in a nationwide clinical trial to test the effectiveness of treating adult heart disease patients with their own stem cells.
The goal of the 20-center clinical study, says local project leader Neal Weintraub, MD, director of cardiology at UC, is to improve the lives of people who suffer from a lack of blood flow to the heart-a painful condition known as chronic myocardial ischemia, or angina.
"The hope is that the stem cells will help to form new vessel networks to deliver blood flow to the heart and alleviate the symptoms of angina," says Weintraub.
Stem cells are "undifferentiated" cells that haven't yet evolved into any specific tissue. For this study, the researchers will collect cells capable of forming endothelium, the inner lining of blood vessel walls, from each patient's blood, and then inject them into regions of the patient's ailing heart that have insufficient blood flow.
What's different about this study, says Weintraub, is that obtaining the cells is less invasive compared with previous methods of harvesting them.
Instead of collecting the stem cells directly from the patient's bone marrow, the standard approach, researchers in this phase-2, double-blind, placebo-controlled study will use a far more comfortable and convenient procedure. They will inject participants with a medication that "mobilizes" or draws the cells out of the bone marrow and into the blood stream, where they can easily be harvested.
The researchers will collect the stem cells using Hoxworth Blood Center's sophisticated Amicus blood cell separator, a process known as apheresis. They will then identify the specific stem cells they need using a state-of-the-art Isolex 300i magnetic cell selection system, after which staff at UCs cardiac catheterization lab will inject the purified cells into the patient's heart.
Lab personnel will use a NOGA XP cardiac navigation system, recently approved by the Food and Drug Administration, to map the heart and guide an experimental catheter, known as a Myostar, to inject the cells into the heart.
No surgery is involved, Weintraub stresses, so patients will be allowed to go home the next day. Their progress will then be followed for a year.
"The risk of this therapy is low, Weintraub says, and it's much less traumatic than performing open heart surgery to deliver the cells.
The body's ability to heal injury and restore normal function "often ends up having something to do with stem cells, Weintraub explains.
"The body has an innate capacity to heal itself, he says. "This ability of stem cells to regenerate and replenish tissue function helps us to heal from injuries and illnesses. It may also help us maintain bodily functions as we age.
"We have known for some time that stem cells capable of forming endothelium circulate in the blood stream and may help to maintain normal blood vessel function.
"So what we're trying to do, says Weintraub, "is enhance nature's own way of healing by isolating these cells and injecting them in concentrated form directly into the heart, where we think they can help improve blood flow to the heart muscle.
The Cincinnati study will eventually involve about a dozen patients. Study candidates, says Weintraub, will be stable angina patients who have no other options for treatment, either through bypass surgery, inserting a stent (a perforated tube that holds the narrowing artery open), angioplasty (expanding the artery with a balloon) or additional medications. Anyone who has recently suffered a heart attack would not be eligible for several months after the attack.
Thanks to the new technology that UC and University Hospital will use in the trial, says Weintraub, "We hope this will be the first of many studies of how stem cells may best be used to treat heart disease. To that end, he says, the state of Ohio has developed a consortium involving the University of Cincinnati and other major medical centers and university-based hospitals that will collaborate on developing and delivering new stem cell therapies to patients.
For more study information, including participation criteria, call (513) 558 2273 or e-mail email@example.com. The trial is funded by the Cellular Therapies business unit of Baxter Healthcare Corporation, which manufacturers the Isolex cell selection system. Weintraub has no financial interest in either Baxter or Johnson & Johnson, which markets the NOGA XP and Myostar technology.