Direct Ventricular Assist Device And Research On Ecg Synchronization Control

Wrapped around the surface of weakened hearts, direct ventricular assist devices compress the weakened heart with mild mechanical force to pump more blood. This paper firstly introduced the principle of direct ventricular assists and a pneumatic direct ventricular assist device in the Lab. In order to avoid the conflict between the native heart pumping action and direct ventricular assisting, ECG synchronization control method is investigated. The feature point of ECG signal, corresponding to the systolic period of native hearts, is detected as the trigger signal used to drive the assist device to compress epicardial surface. Then based on the study of the bioelectricity amplifier & electrocardiogram, this thesis designed the ECG acquisition circuit, acquiring the real-time ECG from the human body. In addition using the correspondence relationship between the heart pumping status and feature points of ECG waveform, QRS complex, corresponding to the systolic period of native hearts, was detected as the trigger signal of assist devices. On CompactRIO acquisition and control platform, the software modules, including ECG acquisition, power frequency interference elimination, QRS detection from ECG waveform, and square wave control signal output, were designed in detail. Finally, experimental tests were carried out for hardware and software modules on the test platform. Experiment results were analyzed, and have proved that the whole system can fully meet the application requirements.