Researchers in Germany were able to 3D-bioprint human heart tissue using hiPSCs (human induced pluripotent stem cells). The tissue can be used as an in vivo model for heart disease. Most notable is that this 3D model can spontaneously beat, as seen in this video.

This video originally appeared on Stem Cell Reports, November 8, 2018 issue.
Atrial-like Engineered Heart Tissue: An In Vitro Model of the Human Atrium