Abstract: A medical device is disclosed which includes a deformable electrode device. In one illustrative embodiment, the deformable electrode is in the form of a braided member, at least a portion of which is electrically conductive. The braided member is extended over an elongated inner member, such as a guide wire, catheter shaft, or the like. A proximal sheath is slidably extended over the inner member and is connected to the braided, electrically conductive member. The proximal sheath may be advanced distally to deform the braided member so that it defines a distally facing, ablative ring, and is operative to form an annular lesion.

Abstract: The system and methods of the invention gauge the amount or quality of the contact between body tissue and one or more electrodes supported on a catheter. In further aspects, the invention concerns methods for controlling power delivery to particular electrodes on a catheter in response to tissue contact data derived from that electrode or other electrodes during the ablation procedure. The invention monitors and processes information concerning the number of pulses of pulsed radio-frequency energy that are delivered during an ablation procedure. The amount or quality of tissue contact is gauged by comparing the number of pulses delivered to a particular electrode during the interval to either the number of pulses delivered to at least one other electrode of the plural electrodes or data derived during the ablation procedure.

Abstract: A steerable catheter control mechanism for manipulating a pair of catheter control wires comprises a slider mechanism coupled to the proximal ends of the control wires and displaceable along a linear path to place a selected one of said wires in tension without placing the other of said wires in compression.

Abstract: A steerable catheter includes control handle having a generally tubular housing with a longitudinal slot therein in which an axially or longitudinally movable two-part slideblock resides, and a generally cylindrical, rotatably mounted thumbwheel surrounding a distal portion of the tubular housing, for controlling the axial translation of the slideblock. The pullwire passes into the distal end of the control handle and is only secured to the proximal part of the two-part slideblock so as to prevent the user from placing the pullwire under compression. A tip radius adjusting wire is attached to and extends distally from a slide actuator in the control handle into and through the main catheter shaft portion. The free distal end of the tip radius adjusting wire is selectably locatable at different positions. The radius of curvature of the tip portion, when deflected, depends upon how far distally into the deflectable tip portion the radius adjusting wire has been advanced by the user.

Abstract: A steerable catheter is disclosed which includes a complexly curved proximal section shaped to seat the catheter relative to an anatomical feature within a patient. The catheter also includes a flexible intermediate section which has comparatively greater flexibility than other sections of the catheter. The flexible intermediate section bends in response to forces applied by an attached steering device and substantially all of the flex in the catheter may be contained within the flexible intermediate section. The catheter further has a pre-shaped distal section which is urged into contact with tissue within the patient when the flexible intermediate section flexes. In a preferred embodiment, the distal section supports a plurality of ring electrodes and is shaped to generally correspond to the physiology of a wall of the heart.

Abstract: A steerable catheter control mechanism comprises a rotatable driver and a deflection device responsive to the driver to selectively secure a pair of control wires. The control wires are positioned such that rotation of the driver reduces the effective deflection device radius while loading a selected wire in tension, thereby maintaining a relatively constant torque acting on the driver and minimizing operator fatigue. The deflection device is also responsive to the driver to selectively place one of the control wires in tension while maintaining the other wire in a static state thereby minimizing control wire fatigue.

Abstract: A steerable catheter is disclosed which includes a complexly curved proximal section shaped to seat the catheter relative to an anatomical feature within a patient. The catheter also includes a flexible intermediate section which has comparatively greater flexibility than other sections of the catheter. The flexible intermediate section bends in response to forces applied by an attached steering device and substantially all of the flex in the catheter may be contained within the flexible intermediate section. The catheter further has a pre-shaped distal section which is urged into contact with tissue within the patient when the flexible intermediate section flexes. In a preferred embodiment, the distal section supports a plurality of ring electrodes and is shaped to generally correspond to the physiology of a wall of the heart.

Abstract: A snap-fit assembly for the distal tip of a catheter is provided. The assembly includes a thermally insulative core and a thermally conductive ablation electrode arranged to interlock with one another by snapping the two together. The core has a proximal end which is shaped to readily fit within the distal tip of an ablation catheter and includes a head which temporarily compresses as it is inserted into the ablation electrode. A method of making the distal tip assembly is also provided.

Abstract: A steerable catheter includes control handle having a generally tubular housing with a longitudinal slot therein in which an axially or longitudinally movable two-part slideblock resides, and a generally cylindrical, rotatably mounted thumbwheel surrounding a distal portion of the tubular housing, for controlling the axial translation of the slideblock. The pullwire passes into the distal end of the control handle and is only secured to the proximal part of the two-part slideblock so as to prevent the user from placing the pullwire under compression. A tip radius adjusting wire is attached to and extends distally from a slide actuator in the control handle into and through the main catheter shaft portion. The free distal end of the tip radius adjusting wire is selectably Iocatable at different positions. The radius of curvature of the tip portion, when deflected, depends upon how far distally into the deflectable tip portion the radius adjusting wire has been advanced by the user.