Abstract: A catheter assembly having a sheath, which includes a side wall enclosing an interior bore, and a distal region. The assembly also has a bendable catheter tube, which is carried for sliding movement in the interior bore. A pull wire also runs through the interior bore of the sheath, preferably within a lumen. The catheter tube has a distal portion with a coupling which joins the distal portion of the catheter tube and the distal portion of the pull wire. Relative movement of the pull wire and the sheath causes bending of the catheter tube outwardly through the opening, in response to sliding movement of the catheter tube within the interior bore toward the distal region of the sheath.

Abstract: An electrode support structure comprises a guide body having at its distal end a flexible spline leg. The spline leg is flexed to define an arcuate shape to facilitate intimate contact against tissue. An electrode element is carried by the spline leg for movement along its axis. The structure includes a control element coupled to the electrode element. The control element remotely imparts force to move the electrode element along the axis of the spline leg. Therefore, in use, the physician can cause the electrode element to travel along a path that the spline leg defines, without otherwise changing the location of the guide body.

Abstract: A device for ablating tissue within the body has an element with an energy emitting region helically wound about and along the axis of the element. The element emits energy to create a lesion in body tissue. A sheath of a non-energy emitting material is movable over the region to adjust the impedance of the region.

Abstract: Systems and methods reduce the effective volume of an atrial appendage by deploying first and second devices into the atrium. The first device carries a first element to affect positioning of the tissue surface in a repositioned orientation. The second device carries a second element to affix the tissue surface in the repositioned orientation affected by the first device. In one embodiment, the first device carries a loop structure having a perimeter. The second device is deployed within the perimeter of said loop structure. The systems and methods attach the second device to an interior surface of an atrial appendage, and pull the atrial appendage through said loop structure to cause inversion thereof.

Abstract: Enhanced electrical connections for electrodes are provided. In one implementation, an electrode body comprises a first electrically nonconductive layer and a second electrically nonconductive layer overlying at least a portion of the first layer. An intermediate region is formed between the first and second layers. An electrically conductive pathway extends within the intermediate region. An formed opening extends to the intermediate region, exposing a part of the electrically conductive pathway. An electrically conductive material is deposited on the second layer so that a part of the electrically conductive material passes through the opening to establish electrical contact between the electrically conductive material and the electrically conductive pathway.

Abstract: An apparatus for ablating body tissue has an electrode for contacting tissue to transmit ablation energy. A tissue temperature sensing element is held in a thermally conducting carrier on the electrode. The carrier holds the tissue temperature sensing element in thermal conductive contact with tissue, while keeping the temperature sensing element in isolation from thermal conductive contact with the electrode. The carrier has prescribed thermal conductive characteristics that significantly improve the sensitivity of the temperature sensing element to tissue temperature and not the temperature of the electrode.

Abstract: A flexible electrode support is bent to define an arcuate shape that extends beyond the distal end of an associated guide body. At least one of the ends of the support is free of attachment to the distal end. By moving the free end, a user can push upon or pull against the structure to alter its arcuate shape to assure intimate contact with tissue.

Abstract: Compound steering assemblies, usable in both diagnostic and therapeutic applications, enable a physician to swiftly and accurately steer the distal section of the catheter in multiple planes or complex curves to position and maintain ablation and/or mapping electrodes in intimate contact with an interior body surface.

Abstract: Systems and associated methods place a temperature sensing element in an "edge region" between an energy transmitting electrode and a non-electrically conducting support body, where higher temperatures are likely to exist. Reliable temperature sensing, which is sensitive to variations in temperatures along the electrode, results.

Abstract: Devices and methods for ablating body tissue use wire wound about a support body in adjacent windings to form one or more elongated electrodes. A connection couples the wire to a source of ablation energy for transmission by the elongated electrode to ablate tissue. The adjacent windings are spaced apart to impart enhanced flexibility to the elongated electrode during use.

Abstract: A system and associated method ablate body tissue using multiple emitters of ablating energy. The system and method convey ablating energy individually to each emitter in a sequence of power pulses. The system and method periodically sense temperature at each emitter and compare the sensed temperatures to a desired temperature established for all emitters to generate a signal individually for each emitter based upon the comparison. The system and method individually vary the power pulse to each emitter based upon the signal for that emitter to maintain the temperatures at all emitters essentially at the desired temperature during tissue ablation.

Abstract: Systems and methods ablate body tissue using an electrode for contacting tissue at a tissue-electrode interface to transmit ablation energy at a determinable power level. The systems and methods include an element to remove heat from the electrode at a determinable rate. The systems and methods employ a processing element to derive a prediction of the maximum tissue temperature condition occurring beneath the tissue-electrode interface. The processing element controls the power level of ablation energy transmitted by the electrode, or the rate at which the electrode is cooled, or both, based, at least in part, upon the maximum tissue temperature prediction.

Abstract: Systems and methods for ablating body tissue use an electrode for contacting tissue to form a tissue-electrode interface. The electrode is adapted to be connected to a source of ablation energy to conduct ablation energy for transmission by the electrode into tissue at the tissue-electrode interface. The electrode is preferably cooled. The systems and methods include multiple temperature sensing elements. One element senses tissue temperature. A second element senses electrode temperature. A third element senses the rate at which the electrode is cooled. The systems and methods control the supply of ablation energy to the electrode based, at least in part, upon the multiple temperatures sensed by the different temperature sensing elements.

Abstract: Systems and associated methods form larger and deeper lesion patterns by shaping a support body with multiple electrodes in ways that increase the density of the electrodes per given tissue area. The support body can carry either elongated, continuous electrodes or arrays of non-contiguous, segmented electrodes.

Abstract: A method of ablating tissue in the heart to treat atrial fibrillation introduces into a selected atrium an energy emitting element. The method exposes the element to a region of the atrial wall and applies ablating energy to the element to thermally destroy tissue. The method forms a convoluted lesion pattern comprising elongated straight lesions and elongated curvilinear lesions. The lesion pattern directs electrical impulses within the atrial myocardium along a path that activates the atrial myocardium while interrupting reentry circuits that, if not interrupted, would cause fibrillation. The method emulates the surgical maze procedure, but lends itself to catheter-based procedures that do not require open heart surgical techniques. A composite structure for performing the method is formed using a template that displays in planar view a desired lesion pattern for the tissue. An array of spaced apart element is laid on the template.

Abstract: A device for ablating tissue within the body has an element with an energy emitting region helically wound about and along the axis of the element. The element emits energy to create a lesion in body tissue. A sheath of a non-energy emitting material is movable over the region to adjust the impedance of the region.