Stem cells injections into the heart can help with agina pectoris (chest pain caused by the obstruction of coronary arteries) when medication, surgery, and angioplasty have failed, according to a new study published in the American Heart Association journal Circulation Research.

The study states that the stem cell injections stimulate the growth of new blood vessels (or at least triggered a healing process), thereby freeing the blood flow and allowing for normal circulation in the heart area.

Patients in the study who were injected with the stem cells had on average 7 agina attacks per week six months after the treatment, compared with 11 in the control group that received placebo shots.  After 12 months, the attacks of the treated group fell to 6 per week. 

Also, the treated group did better in exercise tolerance tests.

Advances in biology have allowed scientists to effect and manipulate natural processes (like the growth of blood vessels).  One of the most potent tools they have discovered to do their biddings is stem cells, which are undifferentiated 'building block' cells that can turn into many different specialized cells of human organs.

Scientists have used stem cells to synthetically grow most human organs.  Moreover, a synthetic windpipe grown from cultivating stem cells has been recently transplanted into the neck of a cancer patient.  The procedure saved the patient's life.

For the Circulation Research agina study, CD34+ stem cells were injected.  A decade ago, these cells were proven to stimulate the formation of new blood vessels, said Douglas W. Losordo, MD, of Chicago's Northwestern University, reported WebMD.