Wearable Soft Robotic Device Supports the Failing Heart in vivo

Soft robots fabricated from low modulus, compliant materials hold significant potential for medical device applications that warrant safe, synergistic interaction with humans. We have recently applied this technology to develop ventricular assistive devices (VADs) that can externally massage the failing heart [1][2]. In heart failure (HF), the heart cannot provide sufficient pumping support to meet the metabolic needs of the body. For patients in end-stage HF, impeller-based VADs can be implanted to supplement heart function. However, these devices are associated with complications including bleeding and thromboembolism as a result of blood clots that form on the non-biologic surfaces of the device. Direct cardiac compression devices are an alternative form of VAD which use an inflatable cuff positioned around the ventricles to apply compressive forces during systole. This allows augmentation of cardiac pumping function without the need to contact the blood directly [3]. Based on this principle, we developed a soft robotic sleeve that fits around the heart and emulates the native cardiac muscle motion in order to restore function to the failing heart [1]. Subsequently, we developed a wearable soft robotic device which could be mechanically coupled to the ventricles [2]. This work demonstrated that actuator synchronization and mechanical coupling to the heart are significant factors for augmenting cardiac output. Here, we report the use of this wearable soft robotic device [2] with additional in vivo data to demonstrate repeatable performance.