Researchers create artificial heart muscles in a lab that beat like the real thing

Researchers in Germany have engineered a tiny stretch of artificial heart muscle that can save 33 million people currently suffering from irregularities in heart rhythm.So far, scientists have yet to find an effective treatment for heart arrhythmias, the most common of which is a disorder called atrial fibrillation. This is particularly because keeping human heart cells alive in a lab long enough to develop and test drugs for illnesses has not been possible so far.Now, researchers from the University Medical Centre-Hamburg have grown strips of heart muscle in a lab.These not only work the same way, express the same genes and resemble heart tissue in every way, they also beat like real heart tissue, as shown in a remarkable video recorded of the muscle.The artificial heart muscle was grown using human induced pluripotent stem cells (hiPSCs), which can be modified to become any cell in the body. These stem cells were treated with a chemical known as retinoic acid, made from Vitamin A, which is important for healthy growth of cells.Artificial cells made from stem cells normally grow flat like a sheet when grown in a lab, but researchers tweaked them to grow in 3D space. They found this 3D model considerably closer in the function and molecular structure to real human heart tissue from patients."These atrial muscle strips represent a great opportunity to model (heart arrhythmia) in a dish and test drugs," Dr Marta Lemme, first author of the study from University Medical Center Hamburg-Eppendorf, told the press. Nevertheless, improvements can still be made to reach even higher similarity with the human atrial tissue.”Their next steps, researchers said, were to artificially induce arrhythmias in these artificial cells and study how electrical impulses and potentially effective drugs can help cure the arrythmias.The study’s findings were published in Stem Cell Reports.