Thursday, February 14, 2013

Stem Cells and Heart Function

On November 6, 2012, at the American Heart Association Scientific Sessions meeting, Drs. Bolli (from the University of Louisville) and Anversa (from Brigham and Women's Hospital in Boston) presented updated data from their SCIPIO trial (Stem Cell Infusion in Patients with Ischemic CardiomyOpathy). This trial was a randomized open-label trial using cardiac stem cells in patients with heart failure after a heart attack, or myocardial infarction.  The data they presented was the follow-up after 2 years.

The trial followed 33 patients who suffered a heart attack with measurable damage to the cardiac muscle.  The patients all had a decreased LVEF (left ventricular ejection fraction), a standard measure of the heart's function measuring the blood ejected from the left ventricle during contraction of the heart muscle.  In the study, the patients' LVEF had to be equal to or under 40%, with a normal LVEF being 50% or more.  The trial involved harvesting patients' stem cells from their hearts during coronary artery bypass surgery and then multiplying these cells in the research team's lab.  When approximately 1 million cells had been produced, the stem cells were then reintroduced into the region of the heart that had been scarred as a result of the heart attack. 

Of the 33 patients, 20 actually received the stem cell therapy while the other 13 were in the control group receiving no stem cells.  The researchers report that the 20 patients receiving stem cell therapy had marked improvement in cardiac function.  Four months after the stem cell infusion, these pateints' average LVEF rose from 29% to 36%.  At the one year mark, LVEF increased by 8.1%, while at the 2 year mark by 12.9%.  The 13 control patients showed no improvement, on average.

Additionally, nine of the patients who received stem cells underwent MRI's and showed marked reduction in the size of the heart muscle scarring and resultant increase in viable muscle tissue.  On average, the infarct size was 33.9 grams prior to treatment and 18.2 grams at the 2 year mark.  The viable left ventricle tissue rose from 146.3 to 164.2 grams.

One patient in particular had suffered from two heart attacks prior to the study.  His LVEF went from 38% to 58% after stem cell therapy, with his heart now showing essentially no ill effects from the prior myocardial infarctions.

The investigators plan to continue following these patients for two more years, and hopefully expand their resaerch with further funding.