Doctors at the Cedars-Sinai Heart Institute have completed the first procedure in which a patient's own heart tissue was used to grow heart stem cells that were then injected back into the patient's heart in an effort to re-grow healthy muscle damaged when the patient suffered a heart attack.

The minimally-invasive procedure is part of a Phase I clinical study. It is the first time cardiologists used cells from a patient's own heart to attempt to heal injured heart muscle.

"This procedure signals a new and exciting era in the understanding and treatment of heart disease," said Eduardo Marban, M.D. Ph.D., director of the Cedars-Sinai Heart Institute, who developed the technique and is leading the clinical trial. "Five years ago, we didn't even know the heart had its own distinct type of stem cells. Now we are exploring how to harness such stem cells to help patients heal their own damaged hearts."

The study is directed by the Cedars-Sinai Heart Institute, with the collaboration of Johns Hopkins University, where Dr. Marban practiced before joining Cedars-Sinai in 2007.

Twenty-four patients are now enrolled in the study. The patients go through a three-step procedure. After undergoing extensive imaging so doctors can pinpoint the exact location and severity of the damage suffered, the patients undergo a minimally-invasive biopsy, with local anesthesia.

Using a catheter inserted through a vein in the neck, doctors remove a small piece of heart tissue, about half the size of a raisin. The heart tissue is then taken to a specialized lab at Cedars-Sinai, where heart stem cells are cultured using methods invented by Marban and his team. It takes about four weeks for the cells to multiply to numbers sufficient for therapeutic use; doctors use approximately 10 to 25 million cells per patient.

In the third and final step, the now-multiplied stem cells are re-introduced into patient's coronary arteries during a second catheter procedure.

All patients in the study had to have experienced heart attacks within four weeks prior to enrolling in the research project. Four patients will receive 12.5 million stem cells and two patients will serve as controls. Later this summer, it is anticipated that 12 more patients will undergo procedures to receive 25 million stem cells, while six additional patients will be monitored as controls.

First Patient is 39 Years Old

The first patient, Kenneth Milles, a 39-year-old controller for a small construction company in the San Fernando Valley, experienced a heart attack on May 10 due to a 99 percent blockage in the left anterior descending artery, a major artery of the heart.

Milles' heart attack left 21 percent of his heart muscle infarcted. He underwent his biopsy May 24, and received his infusion of stem cells on June 29.

Milles and the other patients in the study will be monitored for six months. Complete results are scheduled to be available in late 2010.

Isolating Heart Cells Instead of Bone Marrow

Marban, who holds the Mark Siegel Family Foundation Chair at the Cedars-Sinai Heart Institute and directs Cedars-Sinai's Board of Governors Heart Stem Cell Center, said the cardiac stem cell procedure is a logical step forward from recent studies in which cardiac patients have been treated with stem cells derived from bone marrow.

Studies over the past eight years have shown that more than 500 cardiac patients have experienced modest improvement when treated with bone marrow stem cells. However, bone marrow stem cells are not predestined to regenerate heart muscle. Heart stem cells are naturally programmed to do just that and could prove to be more successful in regrowing healthy cardiac tissue, Dr. Marban says.

"If successful, we hope the procedure could be widely available in a few years and could be more broadly applied to cardiac patients," Marban notes. "For example, if patients are able to re-grow damaged heart muscle via stem cell therapy, there could be lesser demand for expensive and risky treatments such as heart transplants," he says.

Patent Pending

The process to grow the cardiac-derived stem cells involved in the study was developed by Marban when he was on the faculty of Johns Hopkins University. The university has filed for a patent on that intellectual property, and has licensed it to a company in which Dr. Marban has a financial interest. No funds from that company were used to support the clinical study. All funding was derived from the National Institutes of Health, the Donald W. Reynolds Foundation and Cedars-Sinai Medical Center.

Source: Cedars-Sinai Medical Center