Apparatus and methods are described including a blood pump that includes an axial shaft configured for insertion into, and rotation within, a subject's body. The blood pump also includes an impeller coupled to the axial shaft such that, as the axial shaft rotates, the impeller pumps blood of the subject. Proximal and distal radial bearings surround the axial shaft and are configured to radially stabilize the axial shaft while the axial shaft rotates. Proximal and distal sleeves, which are less flexible than the axial shaft, are disposed around the axial shaft, such that the proximal and distal sleeves contact the proximal and distal radial bearings, respectively, as the axial shaft rotates. A ratio between a length of the axial shaft and a combined length of the proximal sleeve and distal sleeve is between 2:1 and 6:1. Other applications are also described.

Apparatus and methods are described including a solid axial shaft having a shaft diameter that is less than 0.8 mm, an impeller configured for insertion into a left ventricle of a heart of a subject and coupled to the axial shaft, and a hollow drive cable coupled, at a distal end of the drive cable, to the axial shaft, and configured to rotate so as to rotate the axial shaft, thereby causing the impeller to pump blood of the subject from the left ventricle. Other applications are also described.

Apparatus and methods are described including a solid axial shaft having a shaft diameter that is less than 0.8 mm, an impeller configured for insertion into a left ventricle of a heart of a subject and coupled to the axial shaft, and a hollow drive cable coupled, at a distal end of the drive cable, to the axial shaft, and configured to rotate so as to rotate the axial shaft, thereby causing the impeller to pump blood of the subject from the left ventricle. Other applications are also described.

Various devices, systems, and techniques are provided for purging blood pumps. A purge apparatus may be provided that may include a housing having a hinged lid defining a first surface of the housing. The hinged lid may be configured to allow access to an internal volume of space of the housing. The housing may have an opening on a second surface opposite the first surface. The housing may define a tubing channel configured to receive at least a portion of a tube. The purge apparatus may include a pumping mechanism configured to be operably connected to a motor through the opening. The pumping mechanism may be disposed within the internal volume of space of the housing. The pumping mechanism may be configured to, during operation, compress the tube extending through the purge apparatus so as to continuously maintain a positive pressure downstream of the pumping mechanism.

Various devices, systems, and techniques are provided for purging blood pumps. A purge apparatus may be provided that may include a housing having a hinged lid defining a first surface of the housing. The hinged lid may be configured to allow access to an internal volume of space of the housing. The housing may have an opening on a second surface opposite the first surface. The housing may define a tubing channel configured to receive at least a portion of a tube. The purge apparatus may include a pumping mechanism configured to be operably connected to a motor through the opening. The pumping mechanism may be disposed within the internal volume of space of the housing. The pumping mechanism may be configured to, during operation, compress the tube extending through the purge apparatus so as to continuously maintain a positive pressure downstream of the pumping mechanism.

A blood pump may be provided. The blood pump may include a blood flow section operably coupled to a distal end of a catheter. The blood flow section may be configured to cause blood to flow into a blood flow inlet of the blood flow section, through the blood flow section, and out of a blood flow outlet. At least one external and/or internal surface of the blood flow section may include at least a portion of a surface modified by one or more fluorinated end groups and/or silicone end groups of an oligomer or copolymer. The surface may be modified by one or more fluorinated end groups of an oligomer. The surface may be modified by one or more silicone end groups of a copolymer. The oligomer or copolymer may include a silicone, a polycarbonate, a polyurethane, a polyamide, a polyethylene, a polypropylene, a polysulfone, or a polyvinyl chloride.

A blood pump may be provided. The blood pump may include a blood flow section operably coupled to a distal end of a catheter. The blood flow section may be configured to cause blood to flow into a blood flow inlet of the blood flow section, through the blood flow section, and out of a blood flow outlet. At least one external and/or internal surface of the blood flow section may include at least a portion of a surface modified by one or more fluorinated end groups and/or silicone end groups of an oligomer or copolymer. The surface may be modified by one or more fluorinated end groups of an oligomer. The surface may be modified by one or more silicone end groups of a copolymer. The oligomer or copolymer may include a silicone, a polycarbonate, a polyurethane, a polyamide, a polyethylene, a polypropylene, a polysulfone, or a polyvinyl chloride.

Methods and apparatus for providing sensory feedback to an operator of a mechanical circulatory support (MCS) device are provided. The method comprises monitoring, using a controller of the MCS device, one or more physiological signals associated with a heart of a patient within which the MCS device is placed, generating an alert signal based, at least in part, on the monitored one or more physiological signals, and transmitting in response to generating the alert signal, a control signal from the controller of the MCS to a feedback device, wherein the feedback device is configured to provide sensory feedback to an operator of the MCS device based on the control signal.

Methods and apparatus for providing sensory feedback to an operator of a mechanical circulatory support (MCS) device are provided. The method comprises monitoring, using a controller of the MCS device, one or more physiological signals associated with a heart of a patient within which the MCS device is placed, generating an alert signal based, at least in part, on the monitored one or more physiological signals, and transmitting in response to generating the alert signal, a control signal from the controller of the MCS to a feedback device, wherein the feedback device is configured to provide sensory feedback to an operator of the MCS device based on the control signal.

Catheter blood pumps that include an expandable conduit coupled to at least one hub shaped to promote smooth blood flow. In some examples, the at least one hub includes non-metallic configuration and the struts comprise a metallic configuration (e.g., nitinol). The hub can include one or more layers, including a combination of Chronoflex and Pebax.