How can you mend a broken heart? One way is by 3D printing an artificial heart using silicone, which is what researchers at ETH Zurich (Swiss Federal Institute of Zurich) have accomplished. Just one thing: It only keeps ticking for about 45 minutes.
Kidding aside, longevity was never the objective of this project. Nicholas Cohrs, a doctoral student in the group led by Wendelin Stark, Professor of Functional Materials Engineering at ETH Zurich, set out to make the first entirely soft artificial heart that mimics the real thing as much as possible. “Our goal is to develop an artificial heart that is roughly the same size as the patient’s own one and which imitates the human heart as closely as possible in form and function,” said Cohrs.
A functioning artificial heart would be a godsend for the approximately 26 million people worldwide who suffer from heart failure, relatively few of whom can count on receiving a donor heart. Blood pumps that are currently used to keep hearts functioning have several disadvantages, including mechanical complications and the absence of a physiological pulse, which can be unnerving for the patient.
The silicone heart was manufactured by means of a 3D-printing, lost-wax casting technique, according to a press release on the ETH Zurich website. It weighs 390 grams and has a volume of 679 cm3. “It is a silicone monoblock with a complex inner structure,” explained Cohrs. This artificial heart has a right and left ventricle, just like a real human heart, but they are separated by an additional chamber instead of a septum. Pressurized air is used to replicate the muscle contractions of the human heart.
As described in a paper published in the scientific journal Artificial Organs, the soft artificial heart fundamentally works and moves in a manner similar to a human heart. It currently has a life span of only about 3,000 beats, after which the material can no longer withstand the strain. “This was simply a feasibility test,” explained Cohrs. “Our goal was not to present a heart ready for implantation, but to think about a new direction for the development of artificial hearts.”