Tiny Beating Hearts Created With Stem Cells at the University of Washington Engineered cardiac tissue will help speed research for a variety of diseases and new drugs Astronaut Jessica Meir “feeds” a set of the University of Washington’s engineered heart tissues (inside the green-topped case at center) riding aboard the International Space Station as part of a test of micro-gravity on heart health. Image courtesy of NASA. The University of Washington (UW) in Seattle has developed engineered heart tissue that beats. Though minuscule, the rice-grain sized tissues hold enormous promise for understanding one of the body’s most essential organ. Heart disease is the world’s leading cause of death. The new beating hearts, a sort of heart in a petri dish or organ in a dish, will allow researches to better understand cardiac function under various conditions or test the cardiac impact of new drugs.