1. Introduction
When heart function is impaired by 30%-50%, noticeable heart failure symptoms can occur. For end-stage heart failure patients, current ventricular assist devices can achieve a flow rate of 3-6 L/min, but invasive implantation methods pose significant risks of thrombosis and infection [1]. Research on non-blood-contact ventricular assist devices, both domestically and internationally, has mainly focused on pneumatic or hydraulic methods [2]. Although these methods can generate high pressures, they do not achieve non-blood-contact within the body. To improve existing ventricular assist devices, this study has preliminarily designed a wireless-powered pneumatic ventricular assist device. The device replaces percutaneous cable energy supply with magnetic resonance wireless energy technology, non-invasive is realized. It uses an internal gasbag to compress the ventricle, achieving non-blood-contact assistance. This approach offers a potential new technological pathway for the treatment of heart failure, but further research and validation are needed.
2. Methods
The pneumatic ventricular assist actuator mainly consists of an external power source, a wireless energy supply unit, a control system, and the actuator. The wireless energy supply unit provides energy to the internal control circuitry and compression actuator, thereby achieving non-invasive and minimizing the risk of secondary infection. The assist actuator is composed of a microcontroller, an air pump, an air storage gasbag, and a compression gasbag. The microcontroller manages the intake and exhaust pumps to control the expansion and contraction of the gasbag, thereby compressing the heart and achieving non-blood-contact assistance.
3. Results
A hollow silicone heart with a Young's modulus similar to that of the human heart was used as the test object to evaluate the assistive compression capability of the actuator at different compression frequencies. The results showed that the actuator could achieve an assistive compression pressure of 2 kPa at human heart rates (60-120 beats/min), meeting 74% of the required assistive pressure for the human heart. After extended testing, the assistive effect showed only a 3.33% reduction, indicating that the actuator can operate effectively for long periods.
4. Conclusion
The pneumatic ventricular assist actuator proposed in this study achieves non-invasive and non-blood-contact assistance, avoiding the thrombus and infection issues associated with traditional heart pumps. Preliminary experimental results indicate that the device can provide long-term, effective ventricular assistance in simulated human environments. However, the device is still in the early stages of exploration and requires further research and validation. It holds potential to become a viable technological pathway for the treatment of heart failure in the future.
References
[1] Weymann A, Foroughi J, Vardanyan R, et al. Artificial muscles and soft robotic devices for treatment of end‐stage heart failure[J]. Advanced Materials, 2023, 35(19): 2207390.
[2] Ranieri S B, Pascaner A F, Camus J M, et al. Towards the Development of a Multipurpose Console to Drive Pneumatic Assist Devices in Severe Heart Failure Refractory to Medical Treatment[C]//2019 Global Medical Engineering Physics Exchanges/Pan American Health Care Exchanges (GMEPE/PAHCE). IEEE, 2019: 1-4.
