Design And Implementation Of A Low-power Wireless Telemetry Implantable Stimulation System

The micro low-power implantable medical electronic system is a device that could be implanted in animals to detect the real-time physiological parameters and have long-term analysis under free state without any constraint. It could achieve the monitoring, forewarning, diagnosis and the tendency’s analysis of physiological condition. With the acquired physiological signals, the system could output requisite stimulation to achieve the physiological intervention and treatment for animals. As this kind of device is always limited by the objectives’size, weight and the monitoring time, the design of our system’s volume, weight, power consumption and biological compatibility are critical. There are similar products abroad which have been applied successfully, however no valid solutions and mature products are available in our country.We completed the design of a low-power wireless implantable telemetry system that can be applied in rats and other bigger animals. The design of our system consists of low-power physiological parameter acquisition circuit, power management circuit, low-power micro controller (MCU), wireless RF transceiver that meet ISM band and bidirectional constant current stimulus circuit. Meanwhile, we developed a matching wireless receiver to achieve the long-term and real-time physiological signals’monitoring and the control of remote wireless stimulation. By the setting of computer program, the system could transmit stimuli to the animals and regulate the settings including stimulating voltage, frequency, pulse width and stimulus mode. Moreover, we have completed the tests and debugging of the system’s hardware and software. The verification experiment of the device was also conducted, which have showed the system fit the need of design and scientific research.The long-term in vivo experiment in New Zealand rabbits indicated our system could continuously collect ECG for more than 60 days. Besides, the atrial stimulation we applied had evoked persistent atrial fibrillation and established the animal model of atrial fibrillation successfully. With the same system, we also stimulated the vagus nerve to improve the cardiac function of heart failure animals.Our study mainly designed and implemented the development of a implantable wireless telemetry stimulation system, which focused on the design of low-power micro electronic system and embedded program to achieve the long-term physiological signals’detection and programed stimulation during pharmacological, physiological, pathological and other medical researches.