Suction detection on an axial blood pump using BEMF data

摘要

The presence or absence of a suction condition in an implantable blood pump is determined at least in part based on a parameter related to flow, such as a parameter related to thrust on the rotor of the pump. A local extreme of the parameter representing the minimum flow during ventricular diastole in an earlier interval is used to establish a threshold value. A value of the parameter representing the minimum flow during ventricular diastole in a later interval is compared to this threshold. If the comparison indicates a substantial decline in the minimum flow between the earlier and later intervals is associated with a suction condition. During the absence of a suction condition, the threshold is continually updated, so that the system does not indicate presence of a suction condition if the flow decreases gradually.

主权项

1. A control circuit for monitoring the operation of an implantable blood pump, the control circuit comprising:
a threshold value determination circuit operative to repeatedly determine a threshold value of a parameter related to thrust along an axis of a rotor of the pump based on values of the parameter occurring during a period of time prior to each determination; a comparison circuit operative to compare one or more values of the parameter with the threshold value from the last previous determination; and a condition determination circuit operative to determine the presence or absence of one of a suction condition and a suction clearance condition based at least in part on the result yielded by the comparison circuit.