Abstract: Methods and apparatus for estimating maximum flow for a heart pump are described. The method comprises receiving data relating motor current to differential pressure measured for a predetermined speed of a motor of the heart pump, extrapolating based on the received data, a first value for the motor current at which the differential pressure is zero, and determining a maximum flow value through the heart pump at the predetermined speed of the motor of the heart pump based, at least in part, on the first value for the motor current.

Abstract: Methods and apparatus for determining flow through a circulatory support device are provided. The method comprises receiving a motor current signal from a motor of the circulatory support device, determining within a time window of the motor current signal, a measured current value at which flow through the circulatory support device is maximum, determining an offset value based, at least in part, on the measured current value, determining based, at least in part, on the received motor current signal, whether an abnormal condition has occurred, adjusting the motor current signal based, at least in part, on the offset value and the determination of whether an abnormal condition has occurred to produce an adjusted motor current signal, and determining the flow through the circulatory support device based, at least in part, on the adjusted motor current signal.

Abstract: Systems and methods for detecting suction events in blood pumps by monitoring pump motor current. A pump suction event is detected based on a comparison of a pulsatility index that is calculated based on a filtered pump motor current signal with a first predetermined threshold or based on a comparison of a calculated index associated with a normalized band-pass filtered pump motor current signal with a second predetermined threshold. A suction event is also detected based on comparisons of both the calculated pulsatility index and the calculated index associated with the normalized band-pass filtered pump motor current signal with respective first and second predetermined thresholds.

Abstract: Provided here are methods of detecting compromised cerebrovascular reactivity in a subject and treating such subject. The method includes acquiring transcranial Doppler signals and cardiac measurements from the subject following a breath-hold maneuver and recording a test set of CBFV measurements. A breath-hold acceleration index is calculated based on a linear regression correlation of temporal variations of the mean velocity across all cardiac cycles during the breath-hold maneuver. The presence of compromised cerebrovascular reactivity in the subject is detected in response to variations in the breath-hold acceleration index of the subject as compared to a healthy individual performing breath-hold maneuver under similar conditions. If the subject has compromised cerebrovascular reactivity, a therapeutically effective compound is administered to the subject along with provision of behavioral modification regimen.