Various systems and methods are provided for reducing pressure at an outflow of a duct such as the thoracic duct or the lymphatic duct. In one embodiment, an indwelling catheter can be configured to be at least partially implanted within a vein of a patient in the vicinity of an outflow port of a duct of the lymphatic system. The catheter can include first and second restrictors each configured to at least partially occlude the vein within which the catheter is implanted and thus to restrict fluid flow within the vein when the restrictors are activated. The restrictors can each be configured to move between an activated configuration, in which the restrictor occludes the vein, and a relaxed configuration, in which the restrictor does not occlude the vein. The catheter can include a pump, such as an axial motor pump, configured to pump fluid through the catheter.

A fluid pump conveys a fluid, such as blood. A fluid channel that is bounded by a channel wall and a rotor arranged in the fluid channel and that is rotatably mounted about a pivot point of the bearing with a mechanical, hydrodynamic and/or hydrostatic, axial and radial bearing. The fluid channel has a spherical section and the rotor has a rotor body and a conveying element that is arranged within the spherical section of the fluid channel and configured to generate a substantially spherical rotational area of the rotor. The spherical center of the spherical section of the fluid channel and the spherical center of the spherical rotational area substantially coincide with the pivot point so that a minimum distance between the rotor and the channel wall is maintained in the spherical section upon a tilting of the rotor.

A method of detecting hypertension in a patient having an implantable blood pump, the method includes operating the implantable blood pump at a first pump set speed during a first period of time. A first flow rate minimum during a cardiac cycle of the patient is measured. during the first period of time. The first pump set speed is reduced by at least 200 rpm during a second period of time after the first period of time to a second pump set speed, the second period of time being less than the first period of time. A second flow rate minimum is measured during a cardiac cycle during the second period of time. If the second flow rate minimum decreases during the second period of time at the second pump set speed by more than a predetermined amount, an alert is generated indicating a presence of hypertension.

A method of determining a cumulative presence of suction in a patient having an implanted blood pump including determining whether at least one suction event occurred during a predetermined time interval for a predetermined number of time intervals and determining the cumulative presence of suction by dividing a sum of a number of predetermined time intervals in which at least one suction event occurred by the predetermined number of time intervals.

Blood pump devices having improved rotary seals for sealing a bearing assembly supporting a rotor provided herein. Such rotary seals are particularly suited for use in blood pump devices that include rotors having cantilevered supported through a sealed mechanical bearing disposed outside a blood flow path of the device to avoid thrombus formation caused by blood contact with the bearing. The rotary seal can include a first and second face seal that are preloaded with a deflectable compliance member incorporated into the pump housing or a pair of magnets. Such rotary seals can instead or further utilize tight fitment between components or a bio-absorbable fill material to seal an interface between the rotor shaft and pump housing to seal the bearing assembly from fluid flowing through the pump.

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.

An implantable blood pump includes a tube including an inner wall, and wherein during operation of the blood pump, the impeller rotates within the tube and a distance between the inner wall of the tube and the thrust bearing decreases as a speed of the impeller increases.

A blood pump having a pump casing with a blood flow inlet and a blood flow outlet, an impeller arranged in said pump casing so as to be rotatable about an axis of rotation. The impeller has blades sized and shaped for conveying blood from the blood flow inlet to the blood flow outlet. There is a drive unit for rotating the impeller, the drive unit having a magnetic core including a plurality of posts arranged about the axis of rotation and a back plate connecting the posts and extending between the posts in an intermediate area. A coil winding is disposed around each of the posts. The coil windings are controllable so as to create a rotating magnetic field. The impeller has a magnetic structure arranged to interact with the rotating magnetic field so as to cause rotation of the impeller.

A blood pump having a pump casing with a blood flow inlet and a blood flow outlet, an impeller arranged in said pump casing so as to be rotatable about an axis of rotation. The impeller has blades sized and shaped for conveying blood from the blood flow inlet to the blood flow outlet. There is a drive unit for rotating the impeller, the drive unit having a magnetic core including a plurality of posts arranged about the axis of rotation and a back plate connecting the posts and extending between the posts in an intermediate area. A coil winding is disposed around each of the posts. The coil windings are controllable so as to create a rotating magnetic field. The impeller has a magnetic structure arranged to interact with the rotating magnetic field so as to cause rotation of the impeller.

This invention concerns an intravascular blood pump for percutaneous insertion into a patient's blood vessel. The blood pump comprises a pump casing having a blood flow inlet and a blood flow outlet, and an impeller arranged in said pump casing so as to be rotatable about an axis of rotation. The impeller has blades sized and shaped for conveying blood from the blood flow inlet to the blood flow outlet. The blood pump comprises a drive unit for rotating the impeller, the drive unit comprising a plurality of posts arranged about the axis of rotation Each of the posts has an impeller-side end pointing towards the impeller with a front surface facing the impeller. A coil winding is disposed around each of the posts so as to create magnetic field lines running through the front surface of each of the posts and controllable so as to create a rotating magnetic field, wherein the impeller comprises a magnetic structure arranged to interact with the rotating magnetic field so as to cause rotation of the impeller. The front surface of at least one of the posts comprises a concavity in which the front surface is inclined downwards towards a central area of the front surface so as to concentrate at least a part of the magnetic field lines running through the front surface.