Abstract: A method of ablating an epicardial tissue region, including positioning a medical device adjacent the epicardial tissue region, the medical device having a first electrode, a second electrode, and a third electrode located in between the first and second electrodes; delivering an irrigation fluid to the tissue region; and ablating at least a portion of the tissue region by sequentially activating the third electrode in a monopolar radiofrequency delivery mode and activating the first and second electrodes in a bipolar radiofrequency delivery mode.

Abstract: A method of assessing lesion quality of an ablated tissue region comprising ablating at least a portion of the tissue region. The reactance of the ablated tissue region is measured at a plurality of frequencies. The lesion quality of the ablated tissue region is determined based on the measured reactance. For example, an untreated tissue reactance value and a predetermined thermally treated tissue region reactance threshold may be determined. The measured reactance at each of the plurality of frequencies is compared to the threshold to determine the lesion quality of the thermally treated tissue region. The thermal treatment of the tissue may be modified based on the lesion quality determination.

Abstract: An atrial ablation catheter with an electrode array particularly adapted to locate and ablate foci of arrhythmia which are required for sustained atrial fibrillation is provided. The array is easily deployed and retracted from the catheter, and presents a proximally oriented electrode array that can be pulled against the septal wall of the left atrium to engage the septal wall.

Abstract: A polyacrylamide tissue phantom embedded with multi-formulated thermochromic liquid crystals for use in the evaluation of RF ablation therapies is provided. The tissue phantom approximates the properties of biological tissue, and therefore provides a suitable substitute for use in testing the effects of RF and other energy-emitting devices on biological tissue. Also provided is a system for using the tissue phantom in the evaluation of RF therapies.

Abstract: Devices, systems and methods are disclosed for the mapping of electrical signals and 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 transformed from a compact, linear configuration to a helical configuration, such as to map and ablate pulmonary vein ostia.

Abstract: A catheter assembly for use in an anatomy can include an elongated body, which can have a proximal end and a distal end. The body can also define a lumen from the proximal end to the distal end. The assembly can include at least one electrode, which can be coupled to the distal end to sense an electrical activity within the anatomy. The assembly can include a core wire, which can be received within the lumen from the proximal end to the distal end. The core wire can be configured to move the distal end from a first configuration to a second configuration. The assembly can also include a necked portion, which can be formed between the proximal end and the distal end to provide increased stiffness to the distal end of the body.

Abstract: A system and method for identifying the location of a medical device within a patient's body may be used to localize the fossa ovalis for trans-septal procedures. The systems and methods measure light reflected by tissues encountered by an optical array. An optical array detects characteristic wavelengths of tissues that are different distances from the optical array. The reflectance of different wavelengths of light at different distances from an optical array may be used to identify the types of tissue encountered, including oxygenated blood in the left atrium as detected from the right atrium through the fossa ovalis.

Abstract: A medical system, including a catheter having a fluid flow path and a distal portion separated from the fluid flow path; a plurality of electrodes coupled to the distal portion; at least one temperature sensor coupled to the distal portion; a heat sink in thermal communication with each electrode and in fluid communication with the fluid flow path; a radiofrequency signal generator in communication with the plurality of electrodes; and a fluid source in fluid communication with the fluid flow path.

Abstract: A medical method is provided, including a medical device having a distal assembly including at least one electrode and at least one treatment element, the medical device generating information regarding at least one of a physiological measurement and an operational parameter of the medical device; a plurality of surface electrodes affixable to a skin of the patient, wherein the surface electrodes are in electrical communication with the distal assembly to obtain position information of the medical device; and a processor pairing the position information and the at least one of a physiological measurement and an operational parameter of the medical device.

Abstract: Devices, systems and methods are disclosed for the ablation of tissue. A steerable ablation catheter can include one or more ablation elements at its distal end and one or more ablation elements fixedly attached to its shaft. The distal end of the ablation catheter can be deflected to assume a number of different deflection geometries in at least one direction along the shaft. One feature of the ablation catheter is that its shaft can comprise materials of differing durometers or stiffnesses attached together at a joint. Methods associated with use of the ablation catheter are also covered.

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 system and method are described for sensing the orientation of a catheter relative to a tissue and regulating the application of power to maintain the tissue at a pre-determined temperature.

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: A radio frequency tissue ablation system with a radio frequency generator, the generator comprising a radio frequency source, at least four independently controllable radio frequency outputs, a user interface and a controller configured to delivery radio frequency energy from the radio frequency source to the radio frequency outputs in one of at least two different output configurations in response to a configuration selection made through the user.

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 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: A medical device including a catheter having a shaft with a distal portion; a first plurality of substantially hemispherical electrodes coupled to the distal portion; a second plurality of substantially hemispherical electrodes coupled to the shaft proximal of the first plurality, where the second plurality of electrodes are oriented substantially orthogonal to the first plurality of electrodes; and an additional electrode coupled to the shaft. A console may have a processor in electrical communication with the first and second plurality of electrodes and the reference electrode, the processor programmed to obtaining a monophasic action potential recording from at least one of the first and second plurality of electrodes.

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 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: A medical device including a catheter having a shaft with a distal portion; a first plurality of substantially hemispherical electrodes coupled to the distal portion; a second plurality of substantially hemispherical electrodes coupled to the shaft proximal of the first plurality, where the second plurality of electrodes are oriented substantially orthogonal to the first plurality of electrodes; and an additional electrode coupled to the shaft. A console may have a processor in electrical communication with the first and second plurality of electrodes and the reference electrode, the processor programmed to obtaining a monophasic action potential recording from at least one of the first and second plurality of electrodes.