Apparatus and methods are described including a left-ventricular assist device that includes a tube configured to traverse a subject's aortic valve, with a distal portion of the tube within the subject's left ventricle. A frame disposed within the distal portion of the tube defines cells, and a width of each of the cells within a cylindrical portion of the frame is less than 2 mm. An inner lining lines at least some of the cylindrical portion of the frame. An impeller is disposed inside the frame such that a gap between an outer edge of the impeller and the inner lining is less than 1 mm. The impeller is stabilized with respect to the frame, such that, during rotation of the impeller, the gap between the outer edge of the impeller and the inner lining is maintained and is substantially constant. Other applications are also described.

A method of determining a presence of suction in a patient having an implantable blood pump from down-sampled log files. The method comprising calculating a waveform index for each of a plurality of flow rate data points from the down-sampled log files. The calculated waveform index is compared with a predetermined waveform index threshold. A non-suction trough baseline is calculated from the plurality of flow rate data points. A difference between a measured trough and a calculated non-suction trough baseline is compared with a predetermined threshold. The presence of suction for each of the plurality of flow rate data points is determined if the calculated waveform index is greater than the predetermined waveform index threshold and the difference between the measured trough and a calculated non-suction trough baseline is greater than the predetermined threshold.

A method of determining a presence of suction in a patient having an implantable blood pump from down-sampled log files. The method comprising calculating a waveform index for each of a plurality of flow rate data points from the down-sampled log files. The calculated waveform index is compared with a predetermined waveform index threshold. A non-suction trough baseline is calculated from the plurality of flow rate data points. A difference between a measured trough and a calculated non-suction trough baseline is compared with a predetermined threshold. The presence of suction for each of the plurality of flow rate data points is determined if the calculated waveform index is greater than the predetermined waveform index threshold and the difference between the measured trough and a calculated non-suction trough baseline is greater than the predetermined threshold.

Catheter blood pumps that include an expandable pump portion. The pump portions include a collapsible blood conduit that defines a blood lumen. The collapsible blood conduits include a collapsible scaffold adapted to provide radial support to the blood conduit. The pump portion also includes one or more impellers.

Catheter blood pumps that include an expandable pump portion. The pump portions include a collapsible blood conduit that defines a blood lumen. The collapsible blood conduits include a collapsible scaffold adapted to provide radial support to the blood conduit. The pump portion also includes one or more impellers.

Intravascular blood pumps and methods of use. The blood pump include a pump portion that includes a collapsible blood conduit defining a blood flow lumen between an inflow and an outflow. The pump portion includes a distal collapsible impeller axially spaced from a proximal collapsible impeller, at least a portion of each of the distal and proximal collapsible impellers disposed between the inflow and the outflow.

Intravascular blood pumps and methods of use. The blood pump include a pump portion that includes a collapsible blood conduit defining a blood flow lumen between an inflow and an outflow. The pump portion includes a distal collapsible impeller axially spaced from a proximal collapsible impeller, at least a portion of each of the distal and proximal collapsible impellers disposed between the inflow and the outflow.

A mechanical circulatory support device is provided. The device has a housing containing separate first and second pumps. Each pump having an inlet, an outlet, and an impeller. The device also having a switching mechanism located within the housing and movable from a first position to a second position to divert blood flow within the housing to an inlet of one of the pumps and/or to bypass blood flow relative to one of the pumps within the housing.

A mechanical circulatory support device is provided. The device has a housing containing separate first and second pumps. Each pump having an inlet, an outlet, and an impeller. The device also having a switching mechanism located within the housing and movable from a first position to a second position to divert blood flow within the housing to an inlet of one of the pumps and/or to bypass blood flow relative to one of the pumps within the housing.

Apparatus and methods are described including a blood pump configured to be placed inside a body of subject. The blood pump includes an impeller, a frame disposed around the impeller, and a distal-tip portion disposed distally with respect to the frame. A duckbill valve is disposed entirely within a distal most 10 mm of the distal-tip portion. The duckbill valve defines a wide inlet and a narrow tip that defines a slit therethrough. The duckbill valve is proximally facing, such that the wide inlet faces a distal end of the distal-tip portion and such that the narrow tip faces away from the distal end of distal-tip portion. Other applications are also described.