In 2020, MSU researcher Aitor Aguirre and his team started creating and perfecting tiny working models of the human heart known as organoids. Now, these organoids can be modified to replicate atrial fibrillation, or A-fib.

Roughly the size of a lentil, the three-dimensional heart organoids are so accurate that researchers can study heart development, diseases and drug responses in ways that were previously impossible. The organoids’ rhythmic beating is so strong that it can be seen without a microscope.