Vacuum-enhanced dielectric elastomer counterpulsation for in-vivo diastolic augmentation

Cardiac assist devices based on dielectric elastomer actuators (DEAs) offer a promising alternative to conventional mechanical circulatory support by providing soft and adaptive mechanical assistance. However, existing DEA-based systems face significant limitations in energy efficiency and effective hemodynamic modulation. This study presents a novel vacuum-enhanced DEA-based counterpulsation device and evaluates its performance in a porcine in-vivo model. We investigated two distinct implementation configurations: a direct attachment to the descending aorta and an integration into a bypass circuit mimicking an ascending aortic attachment. The device was actuated in synchronization with the cardiac cycle to provide real-time mechanical unloading. The results demonstrate that the vacuum-enhanced DEA system significantly improved diastolic augmentation (Mean: 39.1 ± 11.7%; Range: 29.2 to 55.0%) and achieved superior left ventricular unloading, marked by a remarkable reduction in end-diastolic pressure (Mean: −126.1 ± 65.6%; Range: −188.3 to −67.1%). Furthermore, the device reduced stroke work (Mean: −12.3 ± 14.0%; Range: −24.2 to 4.4%) and increased stroke volume (Mean: 3.9 ± 2.2%; Range: 2.5 to 7.1%) compared to baseline (device off). These findings establish vacuum-enhanced DEA actuation as a highly viable and impactful approach for next-generation cardiac assist devices, paving the way for further clinical optimization and application.