Doctors at Northwestern University have shown that adult stem cells can relieve angina pain in heart patients. About 850,000 U.S. heart patients have angina--chest pain caused by blocked coronary arteries--that persists despite available treatments. The study examined 167 patients with refractory angina; patients received either a low or high dose of their own adult stem cells injected into their damaged heart muscle, or a placebo injection. The results, published in the journal Circulation Research, showed that patients who received their adult stem cells experienced significant improvements in angina frequency and exercise tolerance. Dr. Douglas Losordo, lead author on the study, says the improvements in the patients treated with adult stem cells were life altering for many patients. Dr. Losordo also noted:

"To put it in human terms, patients who might have been able to sit and watch TV without symptoms could now walk at a normal pace without chest pain, and someone who could walk at a slow pace might be able to ride a bike."

"Early research across multiple disease categories suggests that stem cells generated within the body in adults may have a therapeutic benefit. This is the first controlled trial treating chronic myocardial ischemia patients with their own stem cells to achieve significant reduction in angina frequency and improvement in exercise tolerance."

"There is an emerging notion that our bodies -- even the bodies of patients with significant disease -- contain this natural biology that can heal. We are just beginning to understand and exploit this pre-installed mechanism for self-repair."

In smaller previous studies reported in 2010, scientists in Florida and Brazil had found that adult stem cells injected directly into the heart could relieve angina in patients, and a Spanish group had also shown some improvement in angina patients' symptoms.

Previous research has also show the ability of adult stem cells to shrink enlarged hearts and also long-term evidence that adult stem cells can treat chronic heart failure.