The present invention relates to a perfusion balloon catheter that has an expandable (enlargeable) inner lumen with a novel design feature that allows a continuous flow through this enlarged lumen sufficient perfusion to the distal lumen of the blood vessel or air passage concurrent to and independently of balloon inflation or deflation resulting in the prolonged dilatation and avoiding the high risks of blood or air flow stricture during balloon inflation.

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 a catheter, a proximal impeller disposed on the catheter inside a proximal impeller housing, and which is configured to pump blood by rotating inside the proximal impeller housing. A distal impeller is disposed on the catheter inside a distal impeller housing, distally to the proximal impeller, and the distal impeller is configured to pump blood by rotating inside the distal impeller housing. A tubular element is disposed between the proximal impeller housing and the distal impeller housing, the tubular element being configured to have a tubular configuration during rotation of the proximal and distal impellers. Other applications are also described.

Apparatus and methods are described including a blood pump that includes a catheter, a first impeller disposed on the catheter, and a second impeller disposed on the catheter, proximally to the first impeller. A control unit drives the first and second impellers to pump blood of a subject, by driving the first and second impellers to rotate. The blood pumps is configured such that (a) the first and second impellers are shaped differently from each other when the first and second impellers are in non-radially-constrained configurations, (b) the first and second impellers are sized differently from each other when the first and second impellers are in non-radially-constrained configurations, and/or (c) the first and second impellers are driven by the control unit to rotate under respective rotation conditions that are different from each other. Other applications are also described.

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 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.

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.

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 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.