Apparatus and methods are described for improving renal function of a patient, including mechanically occluding the patient's inferior vena cava downstream of the renal vein ostium to form an upstream region and a downstream region of the inferior vena cava, and mechanically pumping blood through the inferior vena cava from the upstream region to a discharge location in the downstream region while the inferior vena cava is occluded, wherein the blood remains in the inferior vena cava while being mechanically pumped. Other applications are also described.

Fluid pressure or flow in a human body may be adjusted with circulation or perfusion systems and methods. The system may include a first pump implantable in a chamber or vessel of the human body, and a plurality of struts connected to a housing of the first pump, wherein the struts secure the first pump in a desired location of the chamber or vessel. The system may also include one or more flow modification elements disposed on the first pump, where the flow modification elements direct flow to a desired organ or a desired vessel to adjust pressure or flow as desired.

Systems and methods for improving kidney function. A first mechanical circulatory support system (MCS) is introduced in a patient's heart, and a second mechanical circulatory support system is introduced in a patient's inferior vena cava or renal vein. The second mechanical circulatory support system is operated while the first mechanical circulatory support system is operating. A renal parameter is monitored during. Combined operation of the two mechanical circulatory support systems results in a change in renal parameter, e.g. pressure drop in the renal vein, indicating an improvement in kidney function. Once the renal parameter is determined to be below a target threshold, operation of the second mechanical circulatory support device is stopped.

Systems and methods for improving kidney function. A first mechanical circulatory support system (MCS) is introduced in a patient's heart, and a second mechanical circulatory support system is introduced in a patient's inferior vena cava or renal vein. The second mechanical circulatory support system is operated while the first mechanical circulatory support system is operating. A renal parameter is monitored during. Combined operation of the two mechanical circulatory support systems results in a change in renal parameter, e.g. pressure drop in the renal vein, indicating an improvement in kidney function. Once the renal parameter is determined to be below a target threshold, operation of the second mechanical circulatory support device is stopped.

A catheter devices/systems and methods therefrom are described herein for treating acute kidney injury, especially the contrast-induced acute kidney injury wherein the devices may prevent the contrast dyes from entering into kidney and/or facilitate blood flow of kidney by said catheter system.

A blood flow assist system can include an impeller assembly including an impeller shaft and an impeller on the impeller shaft, a primary flow pathway disposed along an exterior surface of the impeller. The system can include a rotor assembly at a proximal portion of the impeller shaft. A secondary flow pathway can be disposed along a lumen of the impeller shaft. During operation of the blood flow assist system, blood can be pumped proximally along the primary flow pathway and the secondary flow pathway. The system can include a sleeve bearing distal the impeller. The system can include a drive unit having a distal end disposed distal a proximal end of the second impeller. The drive unit comprising a drive magnet and a drive bearing between the drive magnet and the impeller assembly.

Apparatus and methods are described including a blood pump that includes an impeller having proximal and distal end portions, a frame disposed around the impeller, and a shaft member that passes through the proximal and distal end portions of the impeller and that is configured to impart rotational motion to the impeller. The impeller defines a radially-constrained configuration in which the impeller is introduced into a subject's body and a non-radially-constrained configuration in which the impeller is configured to pump blood within the subject's body. The distal end portion of the impeller is configured to slide over the shaft member as the impeller changes from its radially-constrained configuration to its non-radially-constrained configuration. Other applications are also described.

Apparatus and methods are described including identifying a subject as suffering from cardiac dysfunction, congestive heart failure, reduced renal blood flow, increased renal vascular resistance, arterial hypertension, and/or kidney dysfunction, and, in response thereto, reducing blood pressure within a renal vein of the subject, by activating at least one impeller to pump blood from the renal vein into a vena cava of the subject, by the impeller rotating.

A blood pump comprises a pump casing having a blood flow inlet and outlet, and an impeller arranged in said pump casing so as to be rotatable. The impeller has blades sized and shaped for conveying blood from the blood flow inlet to the blood flow outlet. The blood pump comprises an outflow cannula having an upstream end portion, a downstream end portion and an intermediate portion. The upstream end portion is connected to the pump casing such that blood is conveyed from the blood flow outlet through the intermediate portion towards the downstream end portion. The downstream end portion has a blood flow outlet through which blood can exit the outflow cannula. At least a portion of the intermediate portion of the outflow cannula has an outer diameter that is larger than an outer diameter of the pump casing.

Apparatus and methods are described for use with a tributary vessel of a subject that supplies a vein of the subject. Blood within the tributary vessel is mechanically isolated into a compartment that is separated from blood within the vein. Blood flow from the tributary vessel to the vein is controlled by pumping blood from the compartment to the vein. Other applications are also described.