The present disclosure relates to techniques for restricting luminary organs. More specifically, a constriction device is provided, having one or several constriction elements configured to be inflated and thereby expand in a first direction towards the luminary organ to constrict a first portion of the luminary organ for restricting the flow of fluid therethrough.

A subcutaneous arteriovenous graft system includes an arteriovenous graft having an arterial end, a venous end opposite to the arterial end and an internal volume between the arterial end and the venous end, and a valve device that can be arranged in an open state, in which fluid flow through the graft is possible and a closed state in which the fluid flow through the arteriovenous graft is blocked. The valve device is constructed to decrease, in the closed state of the valve device, the internal volume of the complete graft to substantially zero.

The invention relates to a valve used in medical procedures. More specifically the invention relates to an introducer sheath valve used in minimally invasive and conventional surgical procedures. The valve may accommodate a wide range of surgical implement diameters, shapes, and multiple implements without imposing the high frictional forces of known valves.

A dialysis valve includes a tube attached between an artery and a vein which, when elongated, simultaneously narrows in diameter at at least one location. The narrowed portion of the tube decreases the volume and velocity between the arterial and venous side of the patient to prevent damage or intimal hyperplasia on the venous side between dialysis treatments. When the valve is opened for dialysis, an unrestricted blood flow exists between the arterial and venous side, permitting a controlled, open blood flow during dialysis.

A dialysis valve includes a tube attached between an artery and a vein which, when elongated, simultaneously narrows in diameter at at least one location. The narrowed portion of the tube decreases the volume and velocity between the arterial and venous side of the patient to prevent damage or intimal hyperplasia on the venous side between dialysis treatments. When the valve is opened for dialysis, an unrestricted blood flow exists between the arterial and venous side, permitting a controlled, open blood flow during dialysis.

The disclosure includes devices and methods for controlling fluid flow. The devices include a tube configured to receive fluid from a fluid source; and a valve for controlling fluid flow through the tube, the valve responsive to fluid pressure in the tube. The valve includes a first magnet outside the tube at a fixed first distance from the tube and a second magnet outside the tube substantially opposite the first magnet and at a second distance from the tube, the second distance greater than the first distance. The valve includes a ferromagnetic fluid within the tube between the first magnet and the second magnet and held in position by a magnetic field generated by the first magnet. The amount of ferromagnetic fluid is sufficient to seal the tube when the fluid pressure is below a threshold pressure set by the second distance between the second magnet and the tube.

Systems and methods are adapted for treating the carotid artery. The systems include interventional catheters and blood vessel access devices that are adapted for transcervical insertion into the carotid artery. Embodiments of the systems and methods can be used in combination with embolic protection systems including blood flow reversal mechanisms, arterial filters, and arterial occlusion devices.

A system is described herein that can irrigate a tissue site using negative-pressure. The system may include a tissue interface configured to be placed adjacent to the tissue site, and a sealing member configured to be placed over the tissue interface to form a sealed space. The system may also include a negative-pressure source configured to be fluidly coupled to the sealed space and a fluid source. The system may further include an irrigation valve. The irrigation valve can have a fluid inlet configured to be fluidly coupled to the fluid source. The irrigation valve can also have a fluid outlet configured to be fluidly coupled to the sealed space. The irrigation valve may also include a clamp configured to be actuated by the negative-pressure source to regulate fluid flow from the fluid source through the fluid outlet.

Systems, methods, and apparatuses for irrigating a tissue site are described. The system can include a tissue interface and a sealing member configured to be placed over the tissue site to form a sealed space, and a negative-pressure source fluidly coupled to the sealed space. The system includes an irrigation valve having a housing, a piston disposed in the housing, a fluid inlet to fluidly couple a fluid inlet chamber to a fluid source, and a fluid outlet to fluidly couple a fluid outlet chamber to the sealed space. A piston passage extends through the piston and fluidly couples the fluid inlet chamber and the fluid outlet chamber, and a biasing member is coupled to the piston to bias the irrigation valve to a closed position. The negative-pressure source is configured to move the piston between the closed position and an open position to draw fluid to the sealed space.

An arteriovenous graft system is described. The arteriovenous graft system includes an arteriovenous graft that is suited for use during hemodialysis. In order to minimize or prevent arterial steal, at least one valve device is positioned at the arterial end of the arteriovenous graft. In one embodiment, for instance, the arteriovenous graft systems includes a first valve device positioned at the arterial end and a second valve device positioned at the venous end. In one embodiment, the valve devices may include an inflatable balloon that, when inflated, constricts and closes off the arteriovenous graft. If desired, a single actuator can be used to open and close both valve devices.