An impeller includes a hub and a blade supported by the hub. The impeller has a stored configuration in which the blade is compressed so that its distal end moves towards the hub, and a deployed configuration in which the blade extends away from the hub. The impeller may be part of a pump for pumping fluids, such as blood, and may include a cannula having a proximal portion with a fixed diameter, and a distal portion with an expandable diameter. The impeller may reside in the expandable portion of the cannula. The cannula may have a compressed diameter which allows it to be inserted percutaneously into a patient. Once at a desired location, the expandable portion of the cannula may be expanded and the impeller expanded to the deployed configuration. A flexible drive shaft may extend through the cannula for rotationally driving the impeller within the patient.

A heart pump assembly includes an elongate catheter with a proximal portion and a distal portion, a rotor at the distal portion of the elongate catheter, a driveshaft, and a bearing. The rotor can include an impeller blade shaped to induce fluid flow in a first axial direction. The drive shaft may be coupled to or integrally formed with a proximal end of the rotor and can include a pump element formed in a surface of the drive shaft. The bearing can include a bore into which the drive shaft extends. The pump element is shaped so as to induce fluid flow through the bore in a second axial direction which can be the same or opposite to the first axial direction.

A heart pump assembly includes an elongate catheter with a proximal portion and a distal portion, a rotor at the distal portion of the elongate catheter, a driveshaft, and a bearing. The rotor can include an impeller blade shaped to induce fluid flow in a first axial direction. The drive shaft may be coupled to or integrally formed with a proximal end of the rotor and can include a pump element formed in a surface of the drive shaft. The bearing can include a bore into which the drive shaft extends. The pump element is shaped so as to induce fluid flow through the bore in a second axial direction which can be the same or opposite to the first axial direction.

A blood pump includes an impeller; a drive shaft coupled to the impeller and configured to rotate with the impeller; a motor configured to drive the impeller; and a bearing assembly disposed adjacent the motor and configured to receive an end of the drive shaft. The bearing assembly includes a bearing, where the end of the drive shaft is at least partially rounded, and the where the bearing includes a concave depression defined in a first side of the bearing, where the depression is configured to receive the end of the drive shaft. The bearing assembly may include a lubricant chamber configured to hold a lubricant.

A blood pump includes an impeller; a drive shaft coupled to the impeller and configured to rotate with the impeller; a motor configured to drive the impeller; and a bearing assembly disposed adjacent the motor and configured to receive an end of the drive shaft. The bearing assembly includes a bearing, where the end of the drive shaft is at least partially rounded, and the where the bearing includes a concave depression defined in a first side of the bearing, where the depression is configured to receive the end of the drive shaft. The bearing assembly may include a lubricant chamber configured to hold a lubricant.

A blood pump comprises a pump casing having a blood flow inlet and a blood flow outlet connected by a passage, and an impeller arranged in said pump casing so as to be rotatable about an axis of rotation. The impeller is provided with blades sized and shaped for conveying blood along the passage from the blood flow inlet to the blood flow outlet, and is rotatably supported in the pump casing by a first bearing at a first axial end of the impeller and a second bearing axially spaced apart from the first bearing. The first bearing comprises a projection extending along the axis of rotation and connected to one of the impeller and the pump casing and a cavity in the other one of the impeller and the pump casing, the projection comprising an enlarged portion that engages the cavity such that the first bearing and the second bearing are arranged to bear axial forces in the same axial direction.

A blood pump comprises a pump casing having a blood flow inlet and a blood flow outlet connected by a passage, and an impeller arranged in said pump casing so as to be rotatable about an axis of rotation. The impeller is provided with blades sized and shaped for conveying blood along the passage from the blood flow inlet to the blood flow outlet, and is rotatably supported in the pump casing by a first bearing at a first axial end of the impeller and a second bearing axially spaced apart from the first bearing. The first bearing comprises a projection extending along the axis of rotation and connected to one of the impeller and the pump casing and a cavity in the other one of the impeller and the pump casing, the projection comprising an enlarged portion that engages the cavity such that the first bearing and the second bearing are arranged to bear axial forces in the same axial direction.

A blood pump is described that includes an impeller having proximal and distal bushings, at least one helical elongate element, a spring that is disposed inside of the helical elongate element and along an axis around which the helical elongate element winds, and a film of material supported between the helical elongate element and the spring. A frame is disposed around the impeller. A flexible elongate element extends radially from the spring to the helical elongate element, and maintains the helical elongate element within a given distance from the spring, to thereby maintain a gap between an outer edge of a blade of the impeller and an inner surface of the frame, during rotation of the impeller. Other applications are also described.

A blood pump is described that includes an impeller having proximal and distal bushings, at least one helical elongate element, a spring that is disposed inside of the helical elongate element and along an axis around which the helical elongate element winds, and a film of material supported between the helical elongate element and the spring. A frame is disposed around the impeller. A flexible elongate element extends radially from the spring to the helical elongate element, and maintains the helical elongate element within a given distance from the spring, to thereby maintain a gap between an outer edge of a blade of the impeller and an inner surface of the frame, during rotation of the impeller. Other applications are also described.

A blood pump includes an impeller; a drive shaft coupled to the impeller and configured to rotate with the impeller; a motor configured to drive the impeller; and a bearing assembly disposed adjacent the motor and configured to receive an end of the drive shaft. The bearing assembly includes a bearing, where the end of the drive shaft is at least partially rounded, and the where the bearing includes a concave depression defined in a first side of the bearing, where the depression is configured to receive the end of the drive shaft. The bearing assembly may include a lubricant chamber configured to hold a lubricant.