Abstract: An electrode array catheter, typically used for mapping, pacing and ablation, includes a flexible delivery sheath (36, 64) and an electrode assembly (2, 62) slidably mounted within the delivery sheath for movement between retracted and deployed positions. The electrode assembly includes an ablation electrode (10, 90) and a plurality of mapping electrodes (26, 114) which are grouped in pairs and naturally assume a three-dimensional array when deployed. The electrodes are distributed to contact a portion of the chamber wall (130) surrounding the target site. The electrode assembly tip has a coiled conical shape (24) in one embodiment and has a number of axially extending, radially outwardly curved arms (118) in another embodiment. A flat flexible circuit (110), having axially extending electrode traces (112) connecting proximal terminals (108) to distal electrode pads (114), is slit (116) axially and is preformed and to create the curved arms.

Abstract: A dual curve ablation catheter (2), especially suited for treating atrial flutter, includes a shaft (4) with a deflectable tip (20) at the distal end (6) and a handle (10) at the proximal end (8). The tip includes a highly flexible distal segment (30), a relatively stiff intermediate segment (28) and a flexible proximal segment (26) so that pulling on a manipulator wire (16) attached to the distal segment causes the distal segment to curve and engage, for example, an isthmus of tissue (106) adjacent the tricuspid valve (104) and the inferior vena cava (98) and causes the proximal segment to curve and press against the wall (110) of the inferior vena cava so to stabilize the catheter. Ablation energy can be supplied through the ablation electrodes (48, 68) simultaneously or one at a time to ablate tissue at the isthmus without the need for moving the catheter.

Abstract: An electrode catheter (2) includes a handle (4) to which a catheter shaft (6) is mounted. The catheter shaft has a distal end (10) carrying plurality of electrodes (12). Dual purpose wires (18) extend from an electrical connector (14) on the handle, through separate axial lumens (16) in the catheter shaft and to the electrodes. The dual purpose wires are physically secured at their distal and proximal ends to the distal end of the catheter shaft and to the handle, respectively, so that rotation of the handle causes a rotational torque to be transmitted through the dual purpose wires to the distal end of the catheter shaft. Each dual purpose wire has an electrical resistance of no greater than about 0.80 ohms per centimeter and a torsional stiffness of at least about 0.25 to 1.0 inch-ounce (17654 to 70616 dyne-cm) for each 110 cm length of catheter shaft when the proximal end of the catheter shaft is rotated 3 turns. This construction provides a simply constructed, low cost torquing electrode catheter.

Abstract: An atrioventricular valve tissue ablation catheter (2), especially suited for treating Mahaim fibers, includes a shaft (4) with a deflectable tip (20) at the distal end (6) and a handle (10) at the proximal end (8). The tip includes a distal segment (66) curving in one direction and a proximal segment (44) curving in the opposite direction so the distal segment causes the distal segment can engage tissue on either side of the annulus (92) of the tricuspid (or mitral) valve (90). Ablation energy can be supplied through the ablation electrodes (46, 70) simultaneously or one at a time to ablate tissue at the annulus without the need for moving the catheter. Mapping electrodes (38) are provided proximal of the ablation electrodes.

Abstract: A system for checking the initial calibration of a temperature measuring device that provides a temperature measuring signal in a catheter includes a comparison unit for comparing the magnitude of the temperature signal to a reference value indicating the normal body temperature of the patient. The treatment procedure is disabled if the magnitude of the temperature signal is not within a predetermined range of the reference value.

Abstract: A system for delivering radiofrequency energy to ablate cardiac tissue comprises a radiofrequency generator and an intravascular catheter. The catheter includes both a radiofrequency ablation electrode and a temperature sensor within its distal end. Delivery of power to the ablation electrode may then be controlled based on electrode temperature using a cascade control system wherein analog temperature controller adjusts the set point to a secondary power controller. Alternatively, power delivered to the patient can be controlled directly based on a power set point. Reuse of the catheter is prevented by a fuse within the catheter which is sensed prier to power delivery and broken prior to disconnection of the catheter.

Abstract: An electrophysiology catheter (20) comprises a shaft (22) having a first bending stiffness and a deflectable tip (28) secured to the distal end (24) of the shaft with a second bending stiffness less than the first bending stiffness. At least one electrode (34, 36) is mounted to the tip for delivering current to or monitoring electrical activity of tissue. A manipulator wire (58) is coupled to the distal end of the deflectable tip, whereby the deflectable tip may be deflected by axial force applied to the manipulator wire. A stiffener member (66) is axially slidable relative to the tip so as to adjust the tip curvature without removing the catheter from the body. The catheter may further include a core wire (72) configured to rotate the deflectable tip about a longitudinal axis (2) without rotating the proximal end (26) of the catheter shaft, wherein the distal end of the deflectable tip remains in a substantially constant axial position, preferably in a plane perpendicular to the longitudinal axis.

Abstract: A system for delivering radiofrequency energy to ablate tissue comprises a radiofrequency generator and an intravascular catheter. The catheter includes both a radiofrequency ablation electrode and a temperature sensor within its distal end. Delivery of power to the ablation electrode may then be controlled based on electrode temperature using a cascade control system wherein analog temperature controller adjusts the set point to a secondary power controller. Alternatively, power delivered to the patient can be controlled directly based on a power set point. A sinusoidal RF signal is provided to avoid energy attenuation and the sinusoidal RF signal may be pulsed to avoid buildup of coagulum on the catheter tip while providing high power to create large lesions. A verification circuit checks the continuity of circuits in the catheter.

Abstract: An electrophysiology catheter (20) comprises a shaft (22) having a first bending stiffness and a deflectable tip (28) secured to the distal end (24) of the shaft with a second bending stiffness less than the first bending stiffness. At least one electrode (34, 36) is mounted to the tip for delivering current to or monitoring electrical activity of tissue. A manipulator wire (58) is coupled to the distal end of the deflectable tip, whereby the deflectable tip may be deflected by axial force applied to the manipulator wire. A stiffener member (66) is axially slidable relative to the tip so as to adjust the tip curvature without removing the catheter from the body. The catheter may further include a core wire (72) configured to rotate the deflectable tip about a longitudinal axis (2) without rotating the proximal end (26) of the catheter shaft, wherein the distal end of the deflectable tip remains in a substantially constant axial position, preferably in a plane perpendicular to the longitudinal axis.

Abstract: An intracardiac electrical potential reference catheter includes a proximal shaft section in a distal flexible tip section. The flexible tip section shaped in a geometry suitable for performing intracardiac mapping and includes a plurality of electrode axially spaced-apart thereon. The shaft section is formed from a polymeric material and includes a reinforcement layer, typically a stainless steel braid. The flexible tip section is also formed from a polymeric material and is free from any braided reinforcement. A core wire is attached to a proximal housing on the catheter at one end and to a distal electrode tip at the other end. In this way, the torque is transmitted along the length of the catheter by both the reinforced shaft and separately by the core wire.

Abstract: A steerable catheter suitable for radiofrequency ablation of cardiac tissue comprises a catheter shaft with a deflectable tip at the distal end of the shaft. The tip is deflected by means of a shapable handle coupled to pull wires fastened to the distal end of the deflectable tip. A core wire extends from the handle to the distal tip, providing fine positioning of the deflectable tip by applying torque through the core wire to the tip. A spring tube is further provided in the deflectable tip for improved torque transmission and kink-resistance. The catheter has an electrode at the distal end of the deflectable tip for positioning at a target site and applying RF power to accomplish ablation.

Abstract: A steerable catheter suitable for radiofrequency ablation of cardiac tissue comprises a catheter shaft with a deflectable tip at the distal end of the shaft. The tip is deflected by means of a shapable handle coupled to pull wires fastened to the distal end of the deflectable tip. A core wire extends from the handle to the distal tip, providing fine positioning of the deflectable tip by applying torque through the core wire to the tip. A spring tube is further provided in the deflectable tip for improved torque transmission and kink-resistance. The catheter has an electrode at the distal end of the deflectable tip for positioning at a target site and applying RF power to accomplish ablation.