In the context of a number of somewhat confusing recent research reports and trials involving bone marrow derived stem cells and heart therapy, a comparatively large phase II clinical trial has found that stem cells derived from heart failure patients own bone marrow and injected into their hearts improved the function of the left ventricle, the heart's pumping chamber.
Mayo Clinic cardiologist Dr. Robert Simari, chairman of the Cardiovascular Cell Therapy Research Network (CCTRN), the network of five academic centers and associated satellite sites that conducted the study talks about the results in the following video:
"We found that the bone marrow cells did not have a significant impact on the original end points chosen, which involved reversibility of a lack of blood supply to the heart, the volume of the left ventricle of the heart at the end of a contraction, and maximal oxygen consumption derived through a treadmill test," said Simari .
"But interestingly we did find that the very simple measure of ejection fraction was improved in the group that received the cells compared to the placebo group by 2.7 percent." Ejection fraction is the percentage of blood pumped out of the left ventricle during each contraction.
This Phase II clinical trial, designed to test a strategy to improve cardiac function, was an extension of earlier efforts in Brazil in which a smaller number of patients received fewer stem cells. For this new network study, 92 patients received a placebo or 100 million stem cells derived from the bone marrow in their hips in a one-time injection. This was the first study in humans to deliver that many bone marrow stem cells.
The average age of study participants was 63. The researchers found that patients younger than 62 improved more. Their ejection fraction improved by 4.7 percent. The researchers looked at the makeup of these patients' stem cells from a supply stored at a biorepository established by the CCTRN. They found these patients had more CD34+ and CD133+ type of stem cells in their mixture.
Adapted from the Mayo Clinic announcement.