Abstract: A signal processing circuit for controlling operation of an implanted ventricular assist device comprising an input module for receiving one or more signals of a patient from one or more sensors. A processor for processing the received signals is included, the processor configured to compare a total blood output on a left side of the patient's heart with a total blood output on a right side of the patient's heart; determine at least one from the group consisting of the presence of fluid imbalance between the left and right sides of the patient's heart and the absence of fluid imbalance between the left and right sides of the patient's heart based on the comparison; and when the presence of fluid imbalance is determined, control the implanted ventricular device to restore fluid balance between the left and right sides of the patient's heart.

Abstract: A flow rate of blood through an implantable blood pump is determined based on a parameter related to the flow, such as a parameter related to thrust on the rotor of the pump. An amount of current supplied to the pump is used to determine each of a first flow rate value and second flow rate values. Each of the first and second flow rate values, in combination with the parameter related to thrust on the rotor of the pump, are used to calculate a flow rate of blood through the pump.

Abstract: A flow rate of blood through an implantable blood pump is determined based on a parameter related to the flow, such as a parameter related to thrust on the rotor of the pump. An amount of current supplied to the pump is used to determine each of a first flow rate value and second flow rate values. Each of the first and second flow rate values, in combination with the parameter related to thrust on the rotor of the pump, are used to calculate a flow rate of blood through the pump.

Abstract: The flow rate of blood in an implantable blood pump is determined at least in part based on a parameter related to thrust on the rotor of the pump. The parameter may be a parameter related to displacement of the rotor along its axis, such as a function of the back electromotive force generated in one or more coils of the stator. The back electromotive force may be measured during open-phase periods of a particular coil or set of coils, during which no power is applied to the coil or set of coils by the motor drive circuit. The parameter related to thrust may be used in conjunction with the speed of rotation of the rotor, the magnitude of current supplied to the rotor, or both to determine the flow rate. The pump may be controlled responsive to the determined flow rate.

Abstract: 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.

Abstract: The presence or absence of a high pressure condition in an implantable blood pump is determined at least in part based on a comparison between a determined amount of differential pressure across the pump and a pressure threshold value. The amount of differential pressure parameter may be determined based at least in part on a parameter related to flow, such as a parameter related to thrust on the rotor of the pump. In response to determining the presence of a high pressure condition, an updated speed of rotation of the rotor that is less than the rotor's initial speed may be determined. The rotor's speed may be increased when the flow rate of blood is determined to be at least equal to a flow recovery threshold value.

Abstract: A flow rate of blood through an implantable blood pump is determined based on a parameter related to the flow, such as a parameter related to thrust on the rotor of the pump. An amount of current supplied to the pump is used to determine each of a first flow rate value and second flow rate values. Each of the first and second flow rate values, in combination with the parameter related to thrust on the rotor of the pump, are used to calculate a flow rate of blood through the pump.

Abstract: The presence or absence of a high pressure condition in an implantable blood pump is determined at least in part based on a comparison between a determined amount of differential pressure across the pump and a pressure threshold value. The amount of differential pressure parameter may be determined based at least in part on a parameter related to flow, such as a parameter related to thrust on the rotor of the pump. In response to determining the presence of a high pressure condition, an updated speed of rotation of the rotor that is less than the rotor's initial speed may be determined. The rotor's speed may be increased when the flow rate of blood is determined to be at least equal to a flow recovery threshold value.

Abstract: 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.

Abstract: The flow rate of blood in an implantable blood pump is determined at least in part based on a parameter related to thrust on the rotor of the pump. The parameter may be a parameter related to displacement of the rotor along its axis, such as a function of the back electromotive force generated in one or more coils of the stator. The back electromotive force may be measured during open-phase periods of a particular coil or set of coils, during which no power is applied to the coil or set of coils by the motor drive circuit. The parameter related to thrust may be used in conjunction with the speed of rotation of the rotor, the magnitude of current supplied to the rotor, or both to determine the flow rate. The pump may be controlled responsive to the determined flow rate.

Abstract: A pump (100) includes a pump housing (200) having a fluid inlet (114) and a fluid outlet (116). An impeller (252) is disposed within the pump housing (200) and is rotatable about an axis (156) to move fluid from the inlet (114) to the outlet (116). A flexible drive spring (270) connects the impeller to a rotating drive mechanism (312). The spring (270) transmits torque to the impeller (252) from the drive mechanism (312) and preloads the impeller against a surface (232) of the pump housing (200).

Abstract: A method and apparatus for finding the position of an object in a space involves identifying the positions of pixels in an image of the space, which satisfy a condition relating to a pixel property associated with the object, classifying the positions into a group according to classification criteria, and producing a group position representation for the group, from positions classified in the group, the group position representation representing the position of the object in the space.