Seattle-based University of Washington researchers discovered why cell transplants used to repair damage after a heart attack cause arrhythmias and found a possible alternative, The Washington Post reported April 28.
In the study, published April 6 in Cell Stem Cell, researchers altered four genes in heart muscle cells and implanted millions of them into pigs. The MEDUSA cells attached to the pig heart and beat in sync with existing cells. They cut arrhythmias by 95 percent, and the arrhythmias that did occur were over faster.
Researchers also discovered the cardiomyocyte injections cause arrhythmias because the cells are immature and fail to harmonize with the heart's electrical impulses. This forces the heart to beat too quickly, according to the report.
The modified cells could be a viable path for repairing hearts and overcoming irregular heartbeats.
"My mother died of heart disease," lead author Charles Murry, MD, PhD, director of the Institute for Stem Cell and Regenerative Medicine at the University of Washington, told the Post. "I use as a benchmark, 'Would I have put these in my mother?' Knowing how they perform in the pig heart, yes. I would put them in my mother."
However, there are limitations to the study. The five pigs had no sustained heart attacks and had a reduced chance of having irregular heartbeats due to the injected cells. Some researchers have also expressed concern that too much gene editing in heart cells could pose risks for cancer or interfere with vital cell functions.