Methods, systems, and devices are described for treating diseases of the gastrointestinal tract, including ulcerative colitis, by delivering ablative energy to a tissue surface of the gastrointestinal tract and ablating the tissue to a controlled depth. Ablating the tissue may include removing a biofilm layer or coagulating tissue.

Methods, systems, and devices are described for treating diseases of the gastrointestinal tract, including ulcerative colitis, by delivering ablative energy to a tissue surface of the gastrointestinal tract and ablating the tissue to a controlled depth. Ablating the tissue may include removing a biofilm layer or coagulating tissue.

Ablation catheter comprising an elongate member with proximal and distal ends, wherein the distal end is arranged to apply a high energy electrical shock from a plurality of locations along the length of said distal end and wherein said distal end is curved. Preferably the distal end of the elongate member extends in a circle segment.

An electrosurgical instrument end effector includes an active electrode received by an insulating material, the active electrode including a primary suction aperture which provides access to a primary fluid channel extending from the active electrode, through the insulating material, to a lumen. The lumen is arranged to carry fluid to and from a surgical site when in use. The end effector further includes at least one additional fluid channel providing alternative access to the primary fluid channel from the active electrode. The at least one additional fluid channel bypasses the primary suction aperture.

A catheter has a multifunctional virtual tip electrode with a porous substrate and a multitude of surface microelectrodes. The surface microelectrodes are in close proximity to each other and in a variety of configurations so as to sense tissue for highly localized intracardiac signal detection, and high density local electrograms and mapping. The porous substrate allows for flow of conductive fluid for ablating tissue. The surface microelectrodes can be formed via a metallization process that allows for any shape or size and close proximity, and the fluid weeping from the porous substrate provides more uniform irrigation in the form of a thin layer of saline. The delivery of RF power to the catheter tip is based on the principle of virtual electrode, where the conductive saline flowing through the porous tip acts as the electrical connection between the tip electrode and the heart surface. The substrate and the surface electrodes are constructed of MRI compatible materials so that the physician can conduct lesion assessment in real time during an ablation procedure. The surface electrodes include noble metals, including, for example, platinum, gold and combinations thereof.

An electrosurgical instrument end effector includes an active electrode received by an insulating material, the active electrode including a primary suction aperture which provides access to a primary fluid channel extending from the active electrode, through the insulating material, to a lumen. The lumen is arranged to carry fluid to and from a surgical site when in use. The end effector further includes at least one additional fluid channel providing alternative access to the primary fluid channel from the active electrode, wherein the at least one additional fluid channel bypasses the primary suction aperture.

Devices, systems, and methods for therapeutically treating tissue. The devices and methods are suitable for minimally invasive surgery or open surgical procedures. More particularly, methods and devices described herein permit accessing and/or treating areas of tissue with a therapeutic device.

The invention relates to an ablation catheter for treatment of a patient's tissue, for example for a PVI procedure on a patient's heart, comprising an elongated catheter shaft and an ablation portion being arranged at a distal end of the catheter shaft with a plurality of electrodes accommodated along the ablation portion, wherein the ablation portion comprises at least two loop sections forming a three-dimensional spiral. In order to increase safety of ablation treatment, spare adjacent tissue (e.g. nerves, vessels, esophagus) and shorten ablation time, a pitch, or clearance of two neighboring loop sections is greater than an ionization threshold of the medium around the distal section, for example blood or gases resulted from electrolysis. The invention further relates to an operation method of such ablation catheter.

Instrument and systems for applying ablative energy to epicardial tissue via a subxiphoid access surgical approach. The instrument has a head assembly sized and shaped for a subxiphoid surgical approach to a patient's heart and defines a contact face. The head assembly includes a paddle body, a first ablation electrode, and a second ablation electrode. The ablation electrodes are coupled to the paddle body in a spaced apart, spatially-fixed fashion. The ablation electrodes are exteriorly exposed at the contact face. A tubular member extends from the head assembly and maintains wiring connected to the ablation electrodes. The instrument is manipulable to locate the contact face on epicardial tissue of a patient's heart via a subxiphoid surgical approach, such as between the left and right pulmonary vein junctions of the posterior left atrium.

The electrode head includes two working surfaces in accordance with an actual bipolar electrode. These may be manufactured lithographically, exhibiting even more complicated outlines. Working surfaces are depicted, which are structured as annulus sector-shaped, concentrically arranged areas, when projected in a plane. Moreover, a further area is situated centrally, which is disc-shaped in a planar projection. Plasma is ignited alternately at both poles. If the individual concentric zones are situated close enough with respect to each other a continuous plasma layer will result.