A treatment device includes a flexible sheath; a wire configured to be inserted into the sheath; a first treatment member disposed at distal side from the wire; a second treatment member disposed at a distal side from the first treatment member; and a protection member configured to cover the second treatment member when the first treatment member projects from a distal end of the sheath.

Embodiments of the invention are directed to a method of excising tissue including injecting fluid into the submucosa to raise targeted tissue. A first electrode is positioned below the targeted tissue within the injected fluid and a second electrode is positioned adjacent a surface of the raised targeted tissue opposite the first electrode. Electrical current is applied between the first and second electrodes and the targeted tissue is excized with the second electrode.

A tissue segmentation device, controller, and methods therefore are disclosed. The device has an active electrode, a return electrode, a mechanical force application mechanism, voltage and current sensors, and a controller. The controller is configured to control a power output of the segmentation device. The controller has a processing component, responsive to the sensors, configured to execute the following: (a) derive a power factor of power applied to the at least one electrode; and (b) responsive to the deriving a power factor, assign a circuit status to a circuit comprising the at least one electrode. IF (PF0) and ((Vrms/Irms)T), THEN the circuit status is open. IF (PF0) and ((Vrms/Irms)<T), THEN the circuit status is short. PF is the power factor. T is a threshold value.

A method of creating an AV fistula between adjacent first and second blood vessels, includes steps of cutting a hole through the adjacent walls of the first and second blood vessels and inserting a welding catheter into the first vessel, and through the hole into the second vessel, so that a distal end of the welding catheter is disposed within the second vessel. A portion of wall defining the welding catheter is then expanded radially outwardly, and the expanded wall portion is pulled proximally to engage the wall of the second blood vessel and to pull it toward the wall of the first blood vessel. Then, a portion of wall proximal to the first expanded wall portion and disposed in the first blood vessel is expanded radially outwardly, thereby capturing the walls of each of the second and first blood vessels between the two expanded wall portions. Cutting elements on the expanded wall portions are then energized to create a tissue welded elongate aperture between the first and second blood vessels.

A tissue removal system for extracting a tissue specimen from a patient and a related method are disclosed. The system has a flexible container with an opening associated with a proximal end, and a distal end. The system also has a plurality of wires removably coupled to an interior of the flexible container in a pre-collection configuration wherein the plurality of wires form a receiving space for receiving the tissue specimen and wherein the plurality of wires are positioned in a pattern. The pattern is selected to divide the tissue specimen into at least four pieces in response to at least one pulling force on the plurality of wires.

Provided is a high-frequency treatment tool. A positioning member that regulates movement of a second wire part within a sheath relative to a first wire part in a direction of a longitudinal axis of the second wire part is present in the sheath. In a state in which a folded part is located close to a distal end of the sheath, a loop formation part is fed from the distal end of the sheath with the second wire part fixed.

In one embodiment, a method is disclosed in which a retrieval apparatus is coupled to a retrieval portion of an implantable device. The implantable device includes a plurality of expandable members each having a portion that comes into contact with a tissue of a subject when expanded. A force is then provided to the retrieval portion to collapse the implantable device. An electrical current is also provided to the portions of the expandable members that come into contact with the tissue of the subject via the retrieval apparatus.

A device, system, and method for ligating the left atrial appendage without creating pro-arrhythmic tissue. The device may generally include a snare including a thermally transmissive distal portion and a suture including a distal portion, both distal portions having a lasso-shaped configuration that may be positioned proximate the base of the left atrial appendage. Once the distal portions of the snare and the suture are tightened around the base of the left atrial appendage, the thermally transmissive distal portion of the snare may be activated to create an ablation lesion in adjacent left atrial appendage tissue. The lesion may be created with radiofrequency energy or through cryoablation by the circulation of refrigerant within the thermally transmissive distal portion of the snare.

This disclosure is directed to a catheter having a lasso electrode assembly with a movable spine. The lasso electrode assembly may have an array of sensing electrodes and may be configured to engage the ostium of the vessel of a patient. The movable spine may have an ablation electrode and may travel along track around the circumference of the lasso electrode assembly. By adjusting the position of the movable spine, tissue may be ablated to form lesions around a circumference of the vessel.

A tissue segmentation device, controller, and methods therefore are disclosed. The device has an active electrode, a return electrode, a mechanical force application mechanism, voltage and current sensors, and a controller. The controller is configured to control a power output of the segmentation device. The controller has a processing component, responsive to the sensors, configured to execute the following: (a) derive a power factor of power applied to the at least one electrode; and (b) responsive to the deriving a power factor, assign a circuit status to a circuit comprising the at least one electrode. IF (PF 0) and ((Vrms/Irms)T), THEN the circuit status is open. IF (PF 0) and ((Vrms/Irms)<T), THEN the circuit status is short. PF is the power factor. T is a threshold value.