A catheter pump system is disclosed. The catheter pump system can include a shaft assembly and an impeller coupled with a distal portion of the shaft assembly. A motor assembly can impart rotation on the impeller through the shaft assembly, the motor assembly comprising a motor which rotates the shaft assembly. The catheter pump system can include a fluid pathway which conveys fluid proximally during operation of the catheter pump system. A seal can be disposed between the motor assembly and the impeller. The seal can be configured to impede or prevent the fluid from the fluid pathway from entering the motor assembly at least about an outer periphery of the shaft assembly. The seal can comprise an opening through which a portion of the shaft assembly extends.

A suspension of a therapeutic substance (e.g., embolic beads) dispersed within a liquid can be delivered via a catheter by using a bidirectional pump to rapidly draw the mixture of the therapeutic substance and liquid from an external syringe into an internal reservoir, then rapidly push the mixture back out into the external syringe. The rapid operation of the bidirectional pump mixes the two constituents so that the therapeutic substance is temporarily suspended within the liquid. Then, a low-speed pump is used to inject the mixture out via the catheter. In some embodiments, the parameters of the low-speed pump are controlled so that the fluid exiting the catheter will experience laminar flow. When the therapeutic substance comprises embolic beads, this can advantageously prevent reflux of the embolic beads, which can be dangerous.

The disclosure relates to devices and methods for the treatment of edema, which devices use a restrictor for flow compensation. Devices and methods of the invention further use a flow-restrictor in the circulatory system, upstream of an intravascular pump, to balance pressure changes induced by the pump and to compensate for downstream flow. The device may be provided as an indwelling, intravascular catheter with a mechanical pump such as an impeller and a selectively deployable restrictor such as an inflatable balloon. Congestive heart failure or edema is treated by\operating the pump in an innominate vein and using the restrictor for flow compensation, to restrict the upstream flow and thus amplify or maintain pressure reduction at the lymphatic outlet.

The disclosure relates to devices and methods for the treatment of edema that uses an impeller with a balloon that may be mounted on the impeller housing. The invention provides devices and methods for treatment of edema that use an indwelling catheter with an impeller to lower pressure at an outlet of a lymphatic duct and a balloon on the impeller to guide and to restrict blood flow. The balloon restricts return flow from the jugular and guides that flow into the impeller cage. By funneling the flow into the impeller cage, a rate of flow down the vessel may be increased, resulting in a lateral pressure decrease effecting the lymphatic outlet. Because the lymphatic outlet is subject to a pressure decrease, fluids in the lymphatic system drain to the outlet and into the circulatory system.

Various systems and methods are provided for reducing pressure at an outflow of a duct, such as the thoracic duct or the lymphatic duct, for example, the right lymphatic duct. A catheter system 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 system includes first and second selectively deployable restriction members each configured to be activated to at least partially occlude the vein within which the catheter is implanted and to thus restrict fluid within a portion of the vein. The catheter system includes an impeller configured to be driven by a motor to induce a low pressure zone between the restriction members by causing blood to be pumped through the catheter when the restriction members occlude the vein.

Various systems and methods are provided for reducing pressure at an outflow of a duct, such as the thoracic duct or the lymphatic duct, for example, the right lymphatic duct. A catheter system 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 system includes first and second selectively deployable restriction members each configured to be activated to at least partially occlude the vein within which the catheter is implanted and to thus restrict fluid within a portion of the vein. The catheter system includes an impeller configured to be driven by a motor to induce a low pressure zone between the restriction members by causing blood to be pumped through the catheter when the restriction members occlude the vein.

The invention provides methods and devices that improve the flow of lymph without the use of a rotating mechanical pump. Systems and methods of the disclosure use inflatable balloons or similar restriction devices to transiently create impediments to flow in the vena cava. When those transient impediments are removed, the rush of blood to restore flow creates a localized zone of low pressure at an outlet of a lymph duct and lymph out of the lymph duct. Another episode of transient impediment is created and relieved, which encourages additional lymph flow. Using a device such as an inflatable balloon, a series of such episodes may be provided. For example, by causing about ten to twenty episodes of transient impediment and relief, lymph flow may be restored to normal rates and volumes.

A catheter pump system is disclosed. The catheter pump system can include a shaft assembly and an impeller coupled with a distal portion of the shaft assembly. A motor assembly can impart rotation on the impeller through the shaft assembly, the motor assembly comprising a motor which rotates the shaft assembly. The catheter pump system can include a fluid pathway which conveys fluid proximally during operation of the catheter pump system. A seal can be disposed between the motor assembly and the impeller. The seal can be configured to impede or prevent the fluid from the fluid pathway from entering the motor assembly at least about an outer periphery of the shaft assembly. The seal can comprise an opening through which a portion of the shaft assembly extends.

A catheter pump system is disclosed. The catheter pump system can include a shaft assembly and an impeller coupled with a distal portion of the shaft assembly. A motor assembly can impart rotation on the impeller through the shaft assembly, the motor assembly comprising a motor which rotates the shaft assembly. The catheter pump system can include a fluid pathway which conveys fluid proximally during operation of the catheter pump system. A seal can be disposed between the motor assembly and the impeller. The seal can be configured to impede or prevent the fluid from the fluid pathway from entering the motor assembly at least about an outer periphery of the shaft assembly. The seal can comprise an opening through which a portion of the shaft assembly extends.

Apparatus for rupturing muscle fibres in a lower oesophageal sphincter comprises a balloon catheter. A multi-electrode impedance planimetry measuring system comprising a pair of stimulating electrodes and sensing electrodes is located on the catheter within the balloon for monitoring the diameter of the balloon when the balloon is inflated with a liquid saline solution from a reservoir through a flowmeter under the control of a microprocessor. The microprocessor computes the minimum diameter value from signals read from the sensing electrodes each time the cumulative volume of the liquid saline solution in the balloon increases by a predefined unit volume. The microprocessor computes a curve of a plot of the minimum diameter values against the corresponding cumulative volume values and determines the slope at each computed minimum diameter value. Rupture of the muscle fibres of the sphincter is determined at the point of inflection of the curve.