'If a treatment can be found for the damage done by a heart attack to heart muscle, then there is the potential to forestall the serious complications that traditionally result from a heart attack, including disturbances of heart rhythm that can lead to sudden cardiac death, and decreased muscle pumping function that can lead to congestive heart failure,'

The Johns Hopkins researchers who conducted the study initially presented their findings last fall at the 2004 Scientific Sessions of the American Heart Association.

Repair and Reverse Damage

Two participants already have been enrolled in a Phase I clinical trial, which is designed to test the safety of injecting adult stem cells at varying doses in patients who recently have suffered a heart attack. In total, 48 patients will participate in this study, which is taking place at several sites across the country. Results are expected by mid-2006.

"Ultimately, the goal is to develop a widely applicable treatment to repair and reverse the damage done to heart muscle that has been infarcted, or destroyed, after losing its blood supply," says cardiologist Joshua Hare, MD, professor of medicine at The Johns Hopkins University School of Medicine and its Heart Institute, and senior author of the study and lead trial investigator.

Special Kind of Stem Cell

"There is reason for optimism about these findings, possibly leading to a first-ever cure for heart attack in humans," says Dr. Hare.

"If a treatment can be found for the damage done by a heart attack to heart muscle, then there is the potential to forestall the serious complications that traditionally result from a heart attack, including disturbances of heart rhythm that can lead to sudden cardiac death, and decreased muscle pumping function that can lead to congestive heart failure," he notes.

The researchers are using a special kind of stem cell in an early stage of development, called adult mesenchymal stem cells, to avoid potential problems due to the tendency of the human immune system to attack stem cells from sources other than the self.

Bone marrow adult stem cells do not have the same potential to develop into different organ tissues, as do embryonic stem cells, whose use is more controversial.