Novel stem cell treatment could help restore heart’s ability to pump after failure
A patient’s own bone marrow cells can potentially be used to repair the heart and restore healthy blood flow after severe heart failure, researchers at the University of Florida and national colleagues report today. These early results pave the way for new clinical trials and, ultimately, new therapies that could help millions of patients. The findings, presented during the American College of Cardiology’s 61st Annual Scientific Session in Chicago, are from a large multicenter clinical study that also involves researchers at the Texas Heart Institute at St. Luke’s Episcopal Hospital, the Cleveland Clinic, Minnesota Heart Institute and Vanderbilt University. “If results like these could be amplified with either more cells, enhanced cells, or a different cell type they could lead to change in the paradigm for management of severe chronic ischemic heart disease and heart failure,” said UF principal investigator Carl J. Pepine, M.D. “The shift in management would be from current attempts to prevent further damage and maintain status quo, to one of repair and/or replacement of damaged blood vessels and heart muscle.” Almost 6 million people in the United States have heart failure, according to the NIH National Heart Lung and Blood Institute. The condition affects both children and adults and can involve one or both sides of the heart. Heart failure occurs when damage from conditions such as coronary heart disease, high blood pressure and diabetes cause the heart to lose its ability to effectively pump sufficient amounts of blood to the body’s organs. Nicknamed FOCUS, the study of 92 adults is the largest of its kind in this group of patients. The work was conducted between 2009 and 2011 at the five centers, which are part of the Cardiovascular Cell Therapy Research Network, a national consortium funded by the NIH National Heart, Lung and Blood Institute. Originally funded in 2007, the network received the first federal funding for cooperative studies of so-called adult stem cells, in which patients are treated with cells taken from their own bodies. “Studies such as these are able to be completed much faster because of the team approach of the network,” said network director Sonia Skarlatos, Ph.D., who is also deputy director of the division of cardiovascular sciences at the National Heart Lung and Blood Institute. Patients who had heart failure and/or chest pain, called angina pectoris, but were not eligible for standard surgical treatment to improve blood flow, were randomly selected to receive either stem cell treatment or a placebo that did not contain the cells being investigated. In patients treated with stem cell therapy, the percentage of oxygen-rich blood being pumped out of the heart’s left ventricle with each heartbeat increased slightly — just under 3 percent — but notably. A normal percentage for blood pumped from the left ventricle is 55 percent to 70 percent. Patients enrolled had 45 percent or lower pumping volume when they started the study. The improvement in blood flow was also linked to increased proportions of blood-forming bone marrow stem cells called CD34+ and CD133+. The results were more striking among patients who were younger than 62, compared with patients who were 62 or older. This information will help researchers identify which patients are most likely to benefit from cell therapy based on the cell composition of a person’s bone marrow. “This study moves us one step closer to being able to help patients with severe heart failure who have no other alternatives,” said FOCUS principal investigator James T. Willerson, M.D., president and medical director of the Texas Heart Institute.