Cardiovascular disease is a prominent ailment in the United States, but it’s often difficult to find a compatible heart donor. Artificial blood pumps can help extend a patient’s lifespan while they wait to receive a donor heart, or until their own heart recovers. However, artificial hearts are far from perfect. A common issue with artificially produced hearts is that the materials and mechanisms used to simulate a heart pumping are not always compatible with cardiac tissue. Materials like metal and plastic can even damage the blood and surrounding cardiac muscle because of the unnatural movement style.
Nicholas Cohrs, a doctoral student in the group led by Wendelin Stark, Professor of Functional Materials Engineering at ETH Zurich, is part of a team that works to remedy artificial hearts. The team from the Functional Materials Laboratory are pioneering development of a silicon heart that beats almost like a human heart. Made up of silicon, this heart is almost entirely soft.
Weighing 390 grams, the heart has a volume of 679 cm3 and was 3D printed as a single part ‘monoblock’. There’s no need to worry about putting it together like you would other 3D prints, because it is a singular printed piece of silicon. “It is a silicone monoblock with complex inner structure,” explains Cohrs. This artificial heart has a right and a left ventricle, just like a real human heart, though they are not separated by a septum but by an additional chamber. This chamber is in- and deflated by pressurized air and is required to pump fluid from the blood chambers, thus replacing the muscle contraction of the human heart.