Abstract: A method and system for producing deep lesions without the production of high heat. The method generally includes ablating target tissue cells with a device in communication with an energy generator programmable to ablate tissue using heat energy, electroporation, or a combination thereof. The system generally includes a medical device having a plurality of electrodes at a distal end, and an energy generator in communication with the plurality of electrodes, the generator programmable to deliver alternating current energy between approximately 100 volts RMS and approximately 2000 volts RMS or greater. The generator is further programmable to deliver energy in unipolar mode, bipolar mode, and a combination thereof.

Abstract: Devices, systems and methods are disclosed for the ablation of tissue. Embodiments include an ablation catheter that has an array of ablation elements attached to a deployable carrier assembly. The carrier assembly can be constrained within the lumen of a catheter, and deployed to take on an expanded condition. The carrier assembly includes multiple electrodes that are configured to ablate tissue at low power. Systems include an interface unit with a visual display that provides a visual representation of the geometry of the ablation elements and/or provides selection means for selecting an icon provided on the display.

Abstract: A device and system for mapping and/or ablation wherein conductive portions of the electrodes and insulated portions of the electrode are composed of the same material. The system may generally include a medical device coupled to a console, the device including a distal assembly positionable at or near a target tissue region. The distal assembly may include one or more electrodes that include an integrated electrode head and electrode wire. The wire may be insulated by an oxidized layer. Alternatively, the distal assembly may include a plurality of protruding circumferential electrodes that are spaced apart by substantially insulated portions. The electrodes and insulated portions may be composed of the same material, with the insulated portions including an oxidized layer on an external surface.

Abstract: The present invention relates to a method, device, and system for improved mapping and/or ablation of a tissue. The device may generally include an elongate body and a distal assembly affixed to the elongate body that includes a treatment electrode having a conductive mapping region and a selectively conductive ablation region that is conductive of high-frequency current and substantially non-conductive of low-frequency current. Alternatively, the device may generally include a treatment electrode having a conductive mapping or ablation region and a region that is coated with an electrically insulated but thermally conductive layer.

Abstract: A method and system capable of identifying ectopic foci, rotors, or conduction pathways involved in reentrant arrhythmias within cardiac tissue, and then treating identified ectopic foci, rotors, and/or pathways with either lethal or sub-lethal temperatures. The system includes a medical device having one or more mapping elements and one or more treatment elements, and a computer programmable to identify ectopic foci and rotors based at least in part on signals received from the one or more mapping elements at one or more locations.

Abstract: A method for manufacturing a distal portion of a mapping and/or ablation device with fewer components and manufacturing steps than are required for presently known devices. The method generally includes aligning one or more electrodes and electrode wires within a housing mold, overmolding a biocompatible material over the one or more wires and a portion of each of the one or more electrodes, creating a housing component that integrates a dome component and an insulation component. Alternatively, the method generally includes aligning one or more wires within a housing mold so that at least a portion of each wire protrudes from the mold, overmolding a biocompatible material over the one or more wires, thus creating a housing component that integrates a dome component and insulation component. The protruding wire portions are cleaved off and at least a portion of the housing component is coated with a layer of conductive material.

Abstract: A medical device, system and method are provided for thermal medical treatment. A medical device for cryogenic treatment may include a tip and a thermal guard or shield. The tip may be at a distal end of a catheter shaft, having a distal surface and lateral surfaces. The thermal guard may be coupled to the catheter proximal of the distal tip, surrounding the longitudinal axis and exposing the distal surface, to resist heat transfer from body fluids to the lateral surfaces of the tip. An efficiency of heat transfer from selected tissue to be treated to the distal surface of the cryogenic tip is thereby increased.

Abstract: An ablation therapy system and systematic method is provided for treating continuous atrial fibrillation. The therapy system includes a Multi-Channel RF Ablation Generator, an ECG interface, an assembly of at least three ablation catheters, and an ECG interface operably coupling and interfacing the catheters to both an ECG unit and the RF Ablation Generator. The systematic method includes transseptally accessing the Left Atrium (LA) through the septum of the patient's heart, and performing an endocardial pulmonary vein ablation procedure on the pulmonary vein ostial tissue surrounding one or more pulmonary veins in a manner treating aberrant conductive pathways therethrough. After performing the pulmonary vein ablation, the method further includes performing an endocardial atrial septum ablation procedure on the septal tissue in a manner treating aberrant conductive pathways therethrough.

Abstract: A transseptal sheath defining a sheath lumen, a proximal end, and a distal end. A valve disposed within the sheath lumen proximate the distal end. The transseptal sheath defining at least one port along a portion of its periphery proximate the valve.

Abstract: Devices, systems and methods are disclosed for the ablation of tissue and treatment of cardiac arrhythmia. An ablation system includes an ablation catheter that has an array of ablation elements and a location element, an esophageal probe also including a location element, and an interface unit that provides energy to the ablation catheter. The distance between the location elements, determined by calculating means of the system, can be used by the system to set or modify one or more system parameters.

Abstract: Devices, systems and methods are disclosed for the ablation of tissue. Embodiments include an ablation catheter that has an array of ablation elements attached to a deployable carrier assembly. The carrier assembly can be constrained within the lumen of a catheter, and deployed to take on an expanded condition. The carrier assembly includes multiple electrodes that are configured to ablate tissue at low power. Additional embodiments include a system that includes an interface unit for delivering one or more forms of energy to the ablation catheter.

Abstract: A method of detecting a thermocouple short circuit in a medical device, including obtaining a first temperature measurement from a thermocouple of the medical device; obtaining a second temperature measurement from the thermocouple; calculating a rate of change over time between the first and second temperature measurements; comparing the calculated rate of change over time to a predefined rate of change over time threshold; and generating an indication of a thermocouple short circuit based at least in part on the comparison.

Abstract: Devices, systems and methods are disclosed for the ablation of tissue. Embodiments include an ablation catheter which has an array of ablation elements attached to a deployable carrier assembly. The carrier assembly can be constrained within the lumen of a catheter, and deployed to take on an expanded condition.

Abstract: Systems and methods for assessing tissue contact, including positioning an electrode adjacent a tissue region; delivering radiofrequency energy to the electrode, wherein the delivered radiofrequency energy is sufficient to ablate at least a portion of the tissue region; obtaining a plurality of impedance measurements from the electrode during the delivery of the radiofrequency energy; calculating a change in the impedance measurements over a pre-determined time period; and generating an alert if the calculated change is less than a pre-defined value.

Abstract: A method and system for detecting microbubble formation during a radiofrequency ablation procedure. The method includes measuring an impedance of a pair of electrodes, at least one electrode in the pair of electrodes being coupled to a treatment assembly of a medical device. Radiofrequency ablation energy is transmitted between the pair of electrodes. The transmission of radiofrequency ablation energy between the pair of electrodes is terminated when after a predetermined period of time the measured impedance in either of the electrodes in the pair of electrodes is a predetermined percentage above a measured minimum impedance and a measured power is above a predetermined power threshold. An alert is generated indicating at least one of the formation and release of microbubbles proximate the pair of electrodes.

Abstract: Systems and methods for assessing electrode position, including positioning a plurality of electrodes within a heart and proximate a pulmonary vein; obtaining an impedance measurement from each of the plurality of electrodes; determining whether any of the plurality of electrodes is located within the pulmonary vein based at least in part on the obtained impedance measurements; and generating an indication if at least one of the plurality of electrodes is determined to be located within the pulmonary vein.

Abstract: A method and system for detecting a short circuit during a radiofrequency ablation procedure. The method includes measuring an impedance of a pair of electrodes coupled to a treatment assembly of a medical device. Radiofrequency ablation energy is transmitted between the pair of electrodes. The transmission of radiofrequency ablation energy between the pair of electrodes is terminated when after a predetermined period of time the measured impedance in either of the electrodes in the pair of electrodes is below a predetermined threshold impedance value. An alert is generated indicating a short circuit between the pair of electrodes.

Abstract: Catheters and methods for obtaining monophasic action potential (“MAP”) electrograms include a flexible catheter body defining a longitudinal axis, and a distal assembly affixed to the catheter body distal end defining a distal tip. The distal assembly has at least three MAP recording electrodes, and at least one reference electrode for determining reference potential. The recording electrodes are each positioned a radial distance from the longitudinal axis in at least three different radial directions, defining a recording geometry substantially having radial symmetry. The reference electrode is a longitudinal distance from the recording geometry. Optional features include a steerable catheter shaft, one or more radio-frequency ablation electrodes, and a dedicated pacing electrode. Different possible embodiments include a dome housing having the recording electrodes in a fixed spatial arrangement, and a distal loop assembly having an array of electrodes on at least three flexible loop elements.

Abstract: A system and method for anchoring a round catheter pull wire within the distal end of a catheter. A steering deflection mechanism includes a pull ring having a plurality of apertures and one or more receiving slots. The method includes affixing one or more round pull wires to the one or more receiving slots of the pull ring. The shape of the round wire and manner of affixing the wire to the pull ring provide a steering assembly that can withstand greater pull forces while maintaining design integrity.

Abstract: Catheters and methods for obtaining monophasic action potential (“MAP”) electrograms include a flexible catheter body defining a longitudinal axis, and a distal assembly affixed to the catheter body distal end defining a distal tip. The distal assembly has at least three MAP recording electrodes, and at least one reference electrode for determining reference potential. The recording electrodes are each positioned a radial distance from the longitudinal axis in at least three different radial directions, defining a recording geometry substantially having radial symmetry. The reference electrode is a longitudinal distance from the recording geometry. Optional features include a steerable catheter shaft, one or more radio-frequency ablation electrodes, and a dedicated pacing electrode. Different possible embodiments include a dome housing having the recording electrodes in a fixed spatial arrangement, and a distal loop assembly having an array of electrodes on at least three flexible loop elements.