A new study revealed that healthy heart muscle cells increased by 30 percent in animals with ischemic heart disease after receiving cardiosphere-derived cells (CDCs).

The research, conducted at the University at Buffalo School of Medicine and Biomedical Sciences, showed that contrary to previous beliefs that heart cells are terminally differentiated and unable to divide, new heart cells were generated by the animals after they were infused with stem cells.

While most studies have largely focused on regenerating muscle in scarred tissue, the UB research group has shown that cardiac repair could be brought about by infusing the CDCs slowly into coronary arteries of the diseased as well as normal areas of the heart.

"Whereas most research has focused upon irreversible damage and scarring following a heart attack, we have shown that a single CDC infusion is capable of improving heart function in areas of the heart that are viable but not functioning normally," explains John M. Canty Jr., MD, the Albert and Elizabeth Rekate Professor of Medicine in the UB medical school and UB's chief of cardiovascular medicine who is a study co-author.

According to the researchers, infusing stem cell formulations directly into coronary arteries is much simpler as it will deliver the cells throughout the heart, unlike if it is injected directly into heart muscle which requires equipment that is not widely available.

Lead author Gen Suzuki, MD, a research assistant professor of medicine in the UB medical school, they have shown that cells derived from heart biopsies can be expanded outside of the body and slowly infused back into the coronary arteries of animals with chronic dysfunction from restricted blood flow or hibernating myocardium.

"The new cardiac muscle cells are small and function more normally than diseased large, hypertrophied myocytes," Gen Suzuki said.

Still in its preclinical phase, the effectiveness of the research is expected to be determined in patients within two to three years or possibly even sooner.

Co-authors on the paper are Thomas Cimato, M.D., Ph.D., assistant professor of medicine and Merced Leiker, research associate in the UB Division of Cardiovascular Medicine. It was funded by the Department of Veterans Affairs; the Empire State Stem Cell Board; the National Heart, Lung and Blood Institute of the National Institutes of Health; and the Albert and Elizabeth Rekate Fund.