Believe it or not, developing a hole in the heart is more common than you might think. Doctors estimate that about 8 in every 1,000 babies are born with a problem in the heart or blood vessels, half of which will develop ventricular septal defect (VSD) – also known as a hole in the heart.
Although the problem is not always fatal, VSD is still a concern for doctors and patients – one that researchers at the University of Wisconsin-Madison (UW) are working to alleviate. Those researchers have developed a “patch” made from stem cells that could one day be applied to the heart, allowing the organ to heal itself. The new procedure is set to be tested on mice and other animals with the defect.
Similar procedures have been tested before, but have largely failed. The team at UW says this is different, however, because of new ways of working with stem cells.
Scientists can now motivate embryonic stem cells to become the differentiated cells found in individual organs, allowing researchers to create patches for various organs. The mice being used for the test procedure have been genetically engineered to have a more human-like immune response to determine whether or not the immune system will reject the added stem cells. Animal tests will also determine the cells’ efficacy in aligning with the patient’s heartbeat and rhythm – if they can’t the mice could develop life-threatening arrhythmias.
“The excitement here is we’re moving closer to patient applications,” says Timothy Kamp, a professor in the UW School of Medicine and Public Health. “We’re at a stage when we need to see how these cells do in a large animal heart attack model. We’ll be making patches of heart muscle that can be applied to these injured areas.”
Still, it will be a while before the potentially life-saving procedure moves beyond the realm of mice.
“The proposed studies in animal models are essential to develop this novel therapy,” Kamp said, “but the gold standard, of course, is a human patient.”