Abstract: An improved system and method for ablating a tissue site is provided. In one embodiment, the system comprises an ablation catheter employing one or more electrodes and multiple temperature sensors located along the catheter distal end. The temperature sensors control the power applied to the one or more electrodes. A deflection mechanism may be included to provide directional control to the catheter.

Abstract: A catheter ablation system including a catheter having a distal segment carrying at least one electrode extending along the segment and having a number of temperature sensors arranged along the distal segment adjacent the electrode, each providing an output indicative of temperature. The catheter is coupled to a power source which provides R-F energy to the electrode and with temperature processing circuitry coupled to the temperature sensors and the power source which controls power output from the power source as a function of the outputs of the temperature sensors. In a preferred embodiment, the temperature processing circuitry includes circuitry for comparing the temperature indicated by the temperature sensors to a known reference sensor and circuitry for disabling subsequent use of an output of one of the sensors if the output from the sensor differs from the referenced temperature by more than a defined value.

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 deflectable ablation catheter which includes an elongated catheter body with an electrode located along a distal section of the catheter body. The catheter is provided with a deflection wire coupled to the distal end of the catheter body which on longitudinal movement causes deflection of the distal section of the catheter body into a planar curve, and a core wire coupled to a point proximal to the distal section of the catheter body and coupled to the catheter body so that upon application of torque to the wire, the planar curve formed along the distal section is rotated into a second plane. A handle is provided at the proximal end of the catheter and carries controls coupled to the core wire and the deflection wire.

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 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.