Mimics Innovation Awards 2020 Runners Up: Clara Park and Yiling Fan

A bionic “heart” for testing cardiac devices

To develop a high-fidelity in vitro simulator for pre-clinical testing of cardiac devices

Cardiac devices, such as prosthetic valves, need to be rigorously tested in the pre-clinical phase to ensure they fit and perform as intended. However, testing these devices in either synthetic or organic models has its challenges — the complex anatomy and motion of the heart are difficult to recreate with purely synthetic models, ex vivo organic models have limited longevity due to muscle stiffening and decay, while using in vivo animal models is both logistically complex and costly. Combining ideas from previous work on artificial heart models and separate research on an implantable robotic heart sleeve designed to wrap around a live heart to help it pump blood, Clara Park, Yiling Fan, and their team set about developing a durable, anatomically correct, and functionally accurate ‘hybrid’ model that could be used for device testing, physician training, and demonstration purposes.

The biorobotic hybrid heart is based on an explanted porcine heart: the endocardium is chemically preserved to maintain the intracardial structures, while the myocardium is replaced with a synthetic matrix of soft robotic actuators that can be ‘inflated’ to drive the motion of the heart.

To recreate the microscopic fiber orientations of the myocardium — which play a key role in the heart’s pumping motions — the team unraveled a porcine myocardial band and used diffusion tensor magnetic resonance imaging (DT-MRI) to guide the design of the matrix. This synthetic band was then wrapped around the organic endocardium and held in place with a new type of bioadhesive, developed as part of the project. As a last step, the hybrid heart was encased in a silicone covering, cast from the original heart, to ensure a snug fit.

Thanks to the robotic actuators, it is possible to simulate extreme conditions such as exercise, or disease-related conditions such as heart failure (weaker actuation) or myocardial infarction (locally inactivated muscles), and even to mimic a patient-specific fiber orientation as detected by DT-MRI.

In responding to the previously unmet need for realistic, cost-effective, scenario-based cardiac device testing, the researchers made considerable technological advancements, notably in the use of DT-MRI, the creation of a robotic matrix that functions like native heart tissue, and the development of a new bioadhesive.

Given the rising need for cardiac devices and interventions worldwide due to population aging, we felt that this research was particularly pertinent, and deserved to be rewarded for its far-reaching contribution to the future of personalized care in cardiology.