While preliminary, the results of a prospective randomized trial indicate that a minimally invasive approach to cell therapy is feasible for the estimated 40 percent of heart failure patients whose disease is unrelated to coronary blockages and who therefore cannot benefit from bypass procedures. Moreover, the experience so far suggests the novel stem-cell approach may be a viable treatment for these and other heart failure patients, reported Dr. Patel, director of clinical cardiac cell therapies at the McGowan Institute.

All 30 patients enrolled had severe heart failure (New York Heart Association heart failure classifications III and IV) with ejection fraction rates of less than 35 percent. Ejection fraction is a standard measure of heart function and is determined by the total amount of blood that the left ventricle pumps out per heart beat. A patient with good heart function has an ejection fraction of at least 55 percent.

Patients were scheduled to undergo the minimally invasive procedure but were unaware whether they would receive their own bone marrow stem cells or their own serum. Regardless, while under general anesthesia, each patient had bone marrow harvested from their hipbones. The cells believed to have the greatest therapeutic benefit, CD34+ cells, were isolated from the bone marrow and either injected into the hearts of patients randomized for therapy or placed in frozen storage if the patients were randomized to the control group. These patients received the same number of injections into the heart - about 25 to 30 - as the patients in the treatment group but instead of containing their stem cells, the injections were loaded with their serum. Neither group experienced any significant side effects or complications, including abnormal heart rhythms, which had been associated with other stem cell trials.

With a six-month follow-up period now complete, the patients who had been randomized to receive the placebo treatment are now eligible to receive their own bone-marrow stem cells that had been kept frozen.

Last April, Dr. Patel reported the results of a trial looking at stem cell therapy given in conjunction with beating-heart bypass surgery for patients whose hearts were damaged by heart attack or chronic coronary disease. That study involving 20 patients also demonstrated the potential benefits of using a patient’s own bone marrow-derived stem cells to treat their ischemic heart disease.

Dr. Patel conducted his initial trials outside of the United States. He and his colleagues now have U.S. Food and Drug Administration approval to conduct a trial at the University of Pittsburgh that would involve giving stem cells to patients who are being implanted with heart assist devices.

From the McGowan Institute of Regenerative Medicine