My first attempt at printing the heart is pictured below.
Unfortunately, my print was unable to finish, so the superior vasculature is not visible. However, the print did successfully print the smaller collateral vessels of the pulmonary arteries. I also need to experiment with printing the heart without the base and instead printing with supports. The base really takes away from the final product in my opinion. I have printed the heart this past week on the taller Ultimaker Extended so I will see next week if the print turned out. It took about 6.5 hours to print the final product.
I will be collaborating with a group in Peoria this summer to figure out how to make models of the inside of the heart as well. I will hopefully be able to figure out a way to do this using free or open source software. https://twitter.com/GwendolynDerk/status/724360255656751104