Adv. Mater. http://doi.org/p94 (2013)

Credit: © 2013 WILEY

Pneumatic artificial muscles (PAMs) are robust and flexible 'bladders' that can contract when inflated with pressurized air. Because of the simple fabrication methods and their fast response, they are widely used as actuators in robotics and automation. Now Ellen Roche and co-workers assemble arrays of millimetre-sized PAMs in elastomeric matrices to create artificial soft muscular tissues, and demonstrate that these systems can perfectly mimic the complex motion of a human heart. In a three-dimensional mould of a left ventricle, they positioned thin actuators similar to the arrangement of muscle fibres, and embedded them in a polymer layer that has an elastic modulus comparable to that of myocardial tissues. This prototype was able to reproduce the twisting of a healthy ventricle, as well as the abnormal movements induced by partially damaged heart muscles. The application of these soft actuators in artificial organs may require further investigation; however, the researchers suggest that these prototypes could be used as simulators to re-create a heart environment in which the reliability of implantable prosthetic devices, such as valves, can be tested.