Research Focuses on Stem Cell Therapy for Heart Attack, Heart Failure

Stem cells are building blocks that can divide, replenish and repair almost any type of cell in the body. They are being tested in the treatment of medical conditions, ranging from cerebral palsy and spinal cord injury to diabetes and Parkinson’s disease. Early research suggests stem cells may be able to repair damaged heart muscle cells as well.

“Stem cell research is experimental, but has yielded some intriguing early results,” says Thomas Povsic, MD, PhD, a cardiologist who is leading cardiac stem cell therapy trials at Duke. “Overall, the field looks promising, but each individual stem cell type and approach has to go through rigorous clinical testing.”

Enrollment is now underway in two cardiac stem cell therapy trials. One is enrolling people who experienced a major heart attack in the last year. The other is enrolling people who are limited by heart failure symptoms that include shortness of breath and fatigue, and can’t easily manage moderate physical activity.

“Your outcome after a heart attack depends on how much heart damage there is,” Dr. Povsic said. The more severe the damage, the harder it becomes for the heart to work. Eventually that can result in heart failure during which the heart can no longer pump adequate amounts of blood. In addition to making you feel bad, heart failure can increase your risk for heart rhythm problems, and eventually the need for a heart transplant.

The studies hope to ascertain whether cardiac stem cells can reverse that downward spiral, Dr. Povsic said. Neither trial requires patients to undergo a procedure to remove their own stem cells. Rather, the heart stem cells are prepared in the lab. The procedures, which take place in the cath lab, require an injection into the artery leading to the heart, or the heart muscle itself.

The first trial, which hopes to enroll up to 300 patients nationwide, involves an injection of stem cell from the heart into the heart’s main artery one month to one year after a heart attack. The hope is to determine whether stem cell therapy can improve heart function. “We also want to determine whether stem cells can reduce the risk of developing future heart failure,” he said.

The second study is hoping to determine if a different type of stem cell, injected into the heart muscle, can prevent people with heart failure from experiencing frequent hospitalization, other heart-related issues, and reduce their risk of dying from the disease. 

Duke is one of only 40 sites in the U.S. enrolling patients in the international heart failure trial, which requires sophisticated heart mapping technology to accurately place the stem cells.

“The key to this trial is our ability to inject cells into the heart using a special system which allows us to map the inside of the heart,” Dr. Povsic explained. By pinpointing exactly where the stem cells should be placed, “we avoid injecting them into dead areas of heart muscle where cells won’t live. We identify and place the cells where the patient’s heart isn’t getting enough blood and isn’t working well.”

The two stem cell therapies trials are the latest being offered at Duke. Dr. Povsic has been involved in several others whose results are currently being analyzed. “The field is promising so we continue to try new approaches,” he said.