TOTAL ARTIFICIAL HEART SYSTEM AND METHOD FOR PHASE-OFFSET CONTROL USING HIGH-FREQUENCY RIPPLE SPECTRAL CONTENT

This invention relates to a total artificial heart system having first and second rotary blood pumps configured to support systemic and pulmonary circulation, respectively, and a controller that regulates a non-zero relative phase offset between imposed pump cycles in order to reduce undesirable hemodynamic interference ripple. A sensed hemodynamic waveform, such as a pressure or flow waveform, is analyzed in the frequency domain by determining a fundamental frequency from pump command timing and separating spectral content into a baseline component at frequencies not greater than twice the fundamental frequency and a ripple-control component at frequencies above twice the fundamental frequency. The controller computes an interference ripple metric using only the higher-frequency component, holds the mean rotational-speed setpoints of the pumps fixed during evaluation, and updates the relative phase offset only when the ripple metric is reduced while mean-flow and mean-pressure targets remain within allowable ranges. In this manner, the invention selectively suppresses undesired high-frequency interference ripple while preserving desired baseline hemodynamic behavior and maintaining average circulatory performance.