Two groups of scientists have demonstrated that immature cells, called stem cells, when pulled from the bone marrow, can mature into heart muscle and new blood vessels that can repair damaged hearts in rats and mice. The reports appear in the April issue of Nature Medicine and the April 5 issue of Nature . Itescu, director of transplantation immunology at Columbia-Presbyterian Medical Center in New York, is senior researcher for one of the studies.
Heart attacks kill heart muscle by cutting off the blood supply to the muscle.
But even when the blood supply is quickly restored, a process called reperfusion, the heart muscle can sustain permanent damage. When these cells die in a process called secondary loss, they are replaced by scar tissue. The result is heart failure in which the heart enlarges, becomes floppy, and pumps blood inefficiently. People with heart failure have difficulty breathing, suffer chest pain, and are often bedridden. In many cases, these people eventually need heart transplants to survive.