Patients with advanced heart disease who received an experimental stem cell therapy showed slightly improved heart function, researchers said at a major US cardiology conference on Saturday.
The clinical trial involved 92 patients, with an average age of 63, who were picked at random to get either a placebo or a series of injections of their own stem cells, taken from their bone marrow, into damaged areas of their hearts.
The patients all had chronic heart disease, along with either heart failure or angina, and their left ventricles were pumping at less than 45 percent of capacity.
All the participants in the study were ineligible for revascularization surgery, such as coronary bypass to restore blood flow, because their heart disease was so advanced.
Those who received the stem cell therapy saw a small but significant boost in the heart’s ability to pump blood, measuring the increase from the heart’s main pumping chamber at 2.7 percent more than placebo patients.
Study authors described the trial as the largest to date to examine stem cell therapy as a route to repairing the heart in patients with chronic ischemic heart disease and left ventricular dysfunction.
“This is the kind of information we need in order to move forward with the clinical use of stem cell therapy,” said lead investigator Emerson Perin, director of clinical research for cardiovascular medicine at the Texas Heart Institute.
Perin’s research, which was conducted between 2009 and 2011 across five US sites, was presented at the annual American College of Cardiology Conference in Chicago.
The technique involved taking bone marrow samples from the patients and processing the marrow to extract stem cells. Doctors then injected the cells via catheter into the heart’s left ventricle.
The injections, comprising some 100 million stem cells in all, were specifically targeted at damaged areas, identified by real-time electromechanical mapping of the heart.
“With this mapping procedure, we have a roadmap to the heart muscle,” said Perin in a statement released ahead of the presentation in Chicago.
“We’re very careful about where we inject the cells; electromechanical mapping allows us to target the cell injections to viable areas of the heart,” he added, describing the procedure as “relatively quick and painless.”
Heart disease is the leading killer in the United States, claiming nearly 600,000 lives per year, according to the US Centers for Disease Control and Prevention.