Using minimally invasive robotic surgery equipment, researchers injected the stem cells into the damaged hearts. The cells were "labeled" with iron particles so that researchers would be able to see if they engrafted in the pig hearts.
The cells were successfully transplanted in six of seven cases. Subsequent MRI studies showed that the cells took hold in the heart and function improved.
The team used a combination of skeletal myoblasts, or cells that give rise to muscle, and bone-marrow derived cells. Both cell types have been shown to improve the development of new blood vessels and to improve function of injured heart muscle. Both are in human clinical trials as well.
The research is published in the current issue of the Journal of Thoracic and Cardiovascular Surgery.
Once more animal studies are completed, the technique could be applied in human clinical trials.
"In people with heart failure, open surgery can be risky; finding a minimally invasive technique to deliver cell therapy to the damaged cardiac tissue would reduce the risk to patients," said Doris A. Taylor, Ph.D., professor of Physiology, holder of the Medtronic Bakken Chair in Cardiovascular Repair, and co-leader of the study.
The minimally invasive approach would offer several benefits for people in heart failure, Taylor said. It is less dangerous to the patient. It can be done while the heart is still beating, and requires less time under anesthesia. It also offers surgeons a magnified view of the heart and allows them to target the cell infusion more precisely.
Harald Ott, M.D., co-leader of this study, now a surgery resident at Massachusetts General Hospital in Boston, pointed out, "Currently these types of cell therapies, in which stem cells are injected into damaged hearts, are
Source:University of Minnesota