Paving the way for artificial hearts, bioengineers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have successfully created a biologically coherent model of the human ventricle. Building a human heart is important because the heart cannot repair itself from damage like other organs. To do so, however, the researchers needed to recreate the complex structure of the heart including the helical geometries responsible for generating the torsional movements when the heart beats.
Although it is believed that the torsion motion is important for pumping blood at large volumes, scientists have not been able to prove it. This is partly because creating hearts with different geometries is difficult. In the new study published In the journal Science, scientists demonstrated that the alignment of the muscles increases the amount of blood the ventricles can pump during contraction.
“This work is a huge step forward for organ fabrication and brings us closer to our ultimate goal of building a human heart for transplantation.” speak Kit Parker, Tarr Family Professor of Applied Physics and Biological Engineering at SEAS and senior author of the paper.
To come to a conclusion, the scientists came up with a new additive manufacturing method, the Concentrated Rotating Jet (FRJS). This allows them to fabricate helically linked fibers with diameters ranging from a few micrometers to hundreds of nanometers.
With this model, the scientists tried to test the hypothesis of Edward Sallin, former chair of the Department of Biology at the University of Alabama Birmingham School of Medicine, who stated that helical alignment is crucial for magnified fractions.
“The human heart actually has many layers of muscles arranged in a spiral with different connection angles. With FRJS, we can reconstruct those complex structures really accurately, forming single and even four-chambered ventricular structures,” said Huibin Chang, a postdoctoral fellow at SEAS and co. the author of the study, explained.