Stemming the tide of heart failure

New research shows promise for the use of the heart s own stem cells in treating heart failure. Like other stem cells, cardiac stem cells (CSCs) are self-renewing and multipotent so CSCs can differentiate into all three major cardiac tissue types. Thus, in a new small pilot study, these CSCs were used to treat the damage caused by coronary heart disease.

Ischemic heart disease (or coronary artery disease, CAD) is characterized by a blockage in the heart s blood vessels; it is the most common cause of heart failure in the developed world. When severe or progressive, CAD leads to a loss of cardiac muscle tissue and, consequently, a decreased ability of the heart to pump blood, as measured by left ventricular ejection fraction (LVEF). Current treatments cannot restore damaged cardiac tissue yet. But, as was revealed in the most recent study, scientists were able to use cardiac stem cells (CSCs) to regenerate damaged cardiac tissue and improve heart function.

In what was the first human trial of CSCs, researchers from the University of Louisville in Kentucky and Brigham and Women s Hospital at the Harvard Medical School treated 16 severe heart failure patients with the stem cells; an additional seven patients receiving standard care served as the control group. Four months after treatment, 14 of the CSC-treated patients experienced an improved ability of the heart to pump blood, with their LVEF increasing from 30.3 percent to 38.5 percent. At one year, eight stem-cell-treated patients increased their LVEF by over 12 percent. Such results were not observed in the control group.

In addition to this significant increase in ejection fraction, seven CSC-treated patients exhibited a 30 percent decrease in the size of damaged tissue at one year.

Though he concedes that the study is small and preliminary, ACSH's Dr. Gilbert Ross believes these figures are truly astounding and the results are indeed dramatic and promising for people suffering from severe heart failure." However, he also acknowledges that, given the complexities of human studies and the dire prognosis of heart failure, not many with the condition today will see this technology in actual clinical use.