Previous soft robotic ventricular assist devices have generally targeted biventricular heart failure and have not engaged the interventricular septum that plays a critical role in blood ejection from the ventricle. We propose implantable soft robotic devices to augment cardiac function in isolated left or right heart failure by applying rhythmic loading to either ventricle. Our devices anchor to the interventricular septum and apply forces to the free wall of the ventricle to cause approximation of the septum and free wall in systole and assist with recoil in diastole. Physiological sensing of the native hemodynamics enables organ-in-the-loop control of these robotic implants for fully autonomous augmentation of heart function. The devices are implanted on the beating heart under echocardiography guidance. We demonstrate the concept on both the right and the left ventricles through in vivo studies in a porcine model. Different heart failure models were used to demonstrate device function across a spectrum of hemodynamic conditions associated with right and left heart failure. These acute in vivo studies demonstrate recovery of blood flow and pressure from the baseline heart failure conditions. Significant reductions in diastolic ventricle pressure were also observed, demonstrating improved filling of the ventricles during diastole, which enables sustainable cardiac output.

Abstract:Robots that reside inside the body to restore or enhance biological function have long been a staple of science fiction. Creating such robotic implants poses challenges both in signaling between the implant and the biological host as well as in implant design. To investigate these challenges, we created a robotic implant to perform in vivo tissue regeneration via mechano-stimulation. The robot is designed to induce lengthening of tubular organs, such as the esophagus and intestines, by computer-controlled application of traction forces. Esophageal testing in swine demonstrates that the applied forces can induce cell proliferation and lengthening of the organ without a reduction in diameter, while the animal is awake, mobile and able to eat normally. Such robots can serve as research tools for studying mechanotransduction-based signaling and can also be employed clinically for conditions such as long-gap esophageal atresia and short bowel syndrome. One Sentence Summary:We have created a robotic implant for inducing tissue growth in tubular organs and demonstrated its potential through esophageal lengthening in swine.

In this work, a lumped‐parameter Windkessel model of the cardiovascular system that simulates biomechanical parameters of the human physiology is presented. The object‐oriented platform provided by the MATLAB‐based modeling environment SIMSCAPE is employed to compute blood pressures and flows in each heart chamber and at various sites of the vascular tree. The hydraulic domain allows the determination of cardiovascular hemodynamics intuitively from geometrical and mechanical properties of the system, while custom elements model the pumping action of the heart and the effects of respiration on blood flow. The model is validated by comparing predicted hemodynamics with normal physiology during both systole and diastole, demonstrating that changes in arterial pressures with breathing are consistent with reported physiological effects of cardiorespiratory coupling. The capabilities of this platform are explored through two exemplary case studies: i) pressure‐overload heart failure due to aortic constriction, validated in vitro and via finite element analysis, and ii) single‐ventricle Fontan physiology, validated in vitro and compared with the clinical literature. This platform provides a practical tool for the calculation of cardiovascular hemodynamics from hydraulic parameters, enabling the intuitive creation of in silico representations of complex circulatory loops, the planning and optimization of medical interventions, and the prediction of clinically relevant patient‐specific hemodynamics.