E-CAD: Electroactive Polymer-Based Cardiac Assist Device with Low Power Consumption

Abstract

Heart failure (HF) is a major clinical and public health problem. Cardiac assist devices are crucial treatment modalities for end-stage HF, but they still face limitations, such as direct blood contact and high power consumption. We present a lightweight (<60 g), compact, electroactive polymer (EAP)-based cardiac assist device (E-CAD) as a nonblood-contacting, low-power alternative to address these limitations. E-CAD consists of EAP units paired with negative bias springs (NBSs), mounted on a flexible sleeve that wraps around the heart to assist in cardiac compression. The device is designed to be biomimetic to match the regionally varying mechanical stiffness of the heart. Benchtop silicone phantom and ex vivo porcine tests demonstrated E-CAD's ability to increase volume displacement by 1.21-fold in benchtop tests with a silicone phantom and 1.17-fold in ex vivo settings, along with an associated increase in ejection fraction, compared to cases without the device. Furthermore, it operates on low power (<0.3 W), enabling a compact design with a thin driveline (outer diameter = 0.3 mm), which reduces infection risk. In summary, we showed that EAP-based direct cardiac compression was feasible with low power demand. The improvement in cardiac output may translate into clinical benefits for advanced HF patients.