Digital system for P-wave detection and synchronization of the artificial heart

This paper describes the implementation of a microcomputer based P-wave synchronization system for the artificial heart. This system provides for synchronization of the cardiac prosthesis pump with P-wave signals from electrodes implanted in the remnant of the natural atrium. The device carries out the functions of P-wave detection and determines the duration of systole based upon a moving average of the time intervals between successive pulses. The system has been tested both on a mock circulatory system and in vivo on calves. The purpose of the paper is to provide details of the circuitry and algorithms used.