Mechanical circulatory supports configured to operate in series with the native heart are disclosed. In an embodiment, a centrifugal pump is used. In an embodiment, inlet and outlet ports are connected into the aorta and blood flow is diverted through a lumen and a centrifugal pump between the inlet and outlet ports. The supports may create a pressure rise between about 40-80 mmHg, and maintain a flow rate of about 5 L/min. The support may be configured to be inserted in a collinear manner with the descending aorta. The support may be optimized to replicate naturally occurring vortex formation within the aorta. Diffusers of different dimensions and configurations, such as helical configuration, and/or the orientation of installation may be used to optimize vortex formation. The support may use an impeller which is electromagnetically suspended, stabilized, and rotated to pump blood.

The present disclosure is directed generally to mechanical cardiovascular support systems used in the medical field to assist the movement of blood. In particular the present disclosure is directed to an impeller having features that allow improved performance. An annular flow area around a rotating impeller may be variable along the axial length of the impeller. A first radial gap, between a distal region of the impeller and a surrounding tubular housing, may be greater or smaller than a second radial gap, between a proximal region of the impeller and the surrounding tubular housing.

The present disclosure is directed generally to mechanical cardiovascular support systems used in the medical field to assist the movement of blood. In particular the present disclosure is directed to an impeller having features that allow improved performance. An annular flow area around a rotating impeller may be variable along the axial length of the impeller. A first radial gap, between a distal region of the impeller and a surrounding tubular housing, may be greater or smaller than a second radial gap, between a proximal region of the impeller and the surrounding tubular housing.

A temporary, removable mechanical circulatory support heart-assist device has at least two propellers or impellers. Each propeller or impeller has a number of blades arranged around an axis of rotation. The blades are configured to pump blood. The two propellers or impellers rotate in opposite directions from each other. The device can be configured to be implanted and removed with minimally invasive surgery.

A temporary, removable mechanical circulatory support heart-assist device has at least two propellers or impellers. Each propeller or impeller has a number of blades arranged around an axis of rotation. The blades are configured to pump blood. The two propellers or impellers rotate in opposite directions from each other. The device can be configured to be implanted and removed with minimally invasive surgery.

Devices, system, and methods are provided based on a technique for purging a blood pump. The technique may include providing a blood pump having an impeller and providing a fluid comprising a bicarbonate. The technique may include flowing the fluid through a first gap between a bearing and an outer surface of a rotatable shaft coupled to the impeller, the bearing and gap being disposed within a lumen of a tubular member and depending on the flow rate of the fluid and the speed of the impeller, the fluid may flow through the first gap and into a second gap between the bearing and a surface of the impeller facing the bearing. The bicarbonate reduces denaturation and adsorption of any blood proteins in the gap(s).

Devices, system, and methods are provided based on a technique for purging a blood pump. The technique may include providing a blood pump having an impeller and providing a fluid comprising a bicarbonate. The technique may include flowing the fluid through a first gap between a bearing and an outer surface of a rotatable shaft coupled to the impeller, the bearing and gap being disposed within a lumen of a tubular member and depending on the flow rate of the fluid and the speed of the impeller, the fluid may flow through the first gap and into a second gap between the bearing and a surface of the impeller facing the bearing. The bicarbonate reduces denaturation and adsorption of any blood proteins in the gap(s).

A blood pump comprises a pump casing a blood flow inlet and a blood flow outlet connected by a passage, and an impeller. The impeller comprises blades configured to convey blood from the blood flow inlet to the blood flow outlet, the impeller being supported in the pump casing by at least one contact-type bearing comprising a surface of the impeller facing a surface of the pump casing. At least one wash out channel extends through the impeller and is in fluid connection with the passage via a first opening and with the bearing via a second opening. The wash out channel is operatively associated with a secondary pump for pumping blood through the wash out channel towards the bearing. The secondary pump is formed at least partially by said at least one wash out channel extending through the impeller along a direction having at least one tangential directional component.

A blood pump comprises a pump casing a blood flow inlet and a blood flow outlet connected by a passage, and an impeller. The impeller comprises blades configured to convey blood from the blood flow inlet to the blood flow outlet, the impeller being supported in the pump casing by at least one contact-type bearing comprising a surface of the impeller facing a surface of the pump casing. At least one wash out channel extends through the impeller and is in fluid connection with the passage via a first opening and with the bearing via a second opening. The wash out channel is operatively associated with a secondary pump for pumping blood through the wash out channel towards the bearing. The secondary pump is formed at least partially by said at least one wash out channel extending through the impeller along a direction having at least one tangential directional component.

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.