Abstract: The present invention provides a medical system, including a catheter defining an injection lumen, a chamber in fluid communication with the injection lumen, and an exhaust lumen in fluid communication with the chamber; a first temperature sensor positioned in the exhaust lumen proximal to the chamber; a second temperature sensor positioned in the chamber; and a console in electrical communication with the first and second temperature sensors, the controller modifying coolant flow through the medical device based at least in part upon a signal received from the first and second temperature sensor. The system may further include a thermally-conductive element circumscribing a substantial portion of the exhaust lumen proximal to the chamber, where the first temperature sensor is mounted to the thermally-conductive element, and the thermally-conductive element may include at least one of a braid, coil, and band.

Abstract: A method and system for continuously delivering cryotreatment to a treatment device. In one embodiment, the system may include a first PID circuit in the fluid delivery line and a second PID circuit in the fluid return line, and the first and second PID circuits may operate simultaneously to continuously provide coolant to a cryotreatment device during the inflation phase, ablation phase, and warming (or thawing) phase while providing for temperature adjustment. Alternatively, the system may include a bypass line by which coolant may bypass the subcooler system and be delivered to the cryotreatment device at non-ablation temperatures during the inflation phase. During the ablation phase, coolant may flow through the subcooler system.

Abstract: A system and method for the delivery of a medical device to a treatment location. The device may include an elongate body, the elongate body including a plurality of annular segments and a jacket disposed about the plurality of annular segments and defining an interior space, and a vacuum source in fluid communication with the interior space of the jacket. When a vacuum is applied to the interior space of the jacket, the jacket may constrict about the plurality of annular elements, thereby increasing the frictional forces between the plurality of segments and between the plurality of segments and an inner surface of the jacket.

Abstract: A medical device is provided, having an elongate body defining a distal portion and a proximal portion; a first expandable member disposed on the distal portion of the elongate body and defining a cooling chamber therein, the first expandable member having a first rigidity; a second expandable member disposed around the first expandable member to define an interstitial region therebetween, where the second expandable member has a second rigidity less than the first rigidity; a gel disposed within the interstitial region; a coolant flow path in fluid communication with the cooling chamber; and a cryogenic coolant source in fluid communication with the coolant flow path.

Abstract: A method and system for improved lesion creation. The method generally includes positioning a treatment element of a medical device proximate an area of target tissue and operating a control unit in accordance with a duty cycle, that includes at least one freeze-warm cycle, each freeze-warm cycle including: supplying coolant to the treatment element at a first flow rate that causes the treatment element to reach a first temperature, the first temperature causing ablation of the target tissue and cryoadhesion between the treatment element and target tissue, and supplying coolant to the treatment element at a second flow rate that causes the treatment element to reach a second temperature, the second temperature being higher than the first temperature and the second flow rate being lower than the first flow rate, the second temperature being above a temperature at which ablation occurs and below a temperature at which cryoadhesion is broken.

Abstract: A medical device includes a steering element defining a passage for a guide wire. A fluid injection tube defining a proximal and a distal end is also included, wherein a portion of the fluid injection tube is contoured about a portion of the steering element. A plurality of injection ports may be disposed in the portion of the fluid injection tube contoured about the steering element.

Abstract: A method and system for creating permanent lesions in an area of target tissue, such as tissue at or proximate a junction between a pulmonary vein and the left atrium. The method may generally include positioning a medical device in contact with a pulmonary vein ostium, ablating the tissue, and recording a plurality of temperature measurements from one or more of three temperature sensors. The device may include an occlusion element in communication with a coolant source, a first sensor located distal of the occlusion element, a second sensor located proximal of the occlusion element, and a third sensor located in the occlusion element. One or more temperature measurements may be compared with each other to assess occlusion of the pulmonary vein, and/or may be compared with a set of reference temperatures to predict a real-time temperature within the target tissue.

Abstract: The present invention provides a medical system, including a catheter defining an injection lumen, a chamber in fluid communication with the injection lumen, and an exhaust lumen in fluid communication with the chamber; a first temperature sensor positioned in the exhaust lumen proximal to the chamber; a second temperature sensor positioned in the chamber; and a console in electrical communication with the first and second temperature sensors, the controller modifying coolant flow through the medical device based at least in part upon a signal received from the first and second temperature sensor. The system may further include a thermally-conductive element circumscribing a substantial portion of the exhaust lumen proximal to the chamber, where the first temperature sensor is mounted to the thermally-conductive element, and the thermally-conductive element may include at least one of a braid, coil, and band.

Abstract: The present invention provides a medical device having an catheter body defining proximal and distal portions, and a guidewire lumen at least partially disposed within and movable within the catheter body. The medical device may include an expandable element defining a proximal end and a distal end, wherein the proximal end is coupled to the distal portion of the catheter body and the distal end is coupled to the guidewire lumen. In addition, an actuator element may be coupled to the guidewire lumen for longitudinal movement thereof, and a tensioning element may further be coupled to the guidewire lumen to bias the guidewire lumen and/or the expandable element towards a particular geometric configuration.

Abstract: A medical device includes a steering element defining a passage for a guide wire. A fluid injection tube defining a proximal and a distal end is also included, wherein a portion of the fluid injection tube is contoured about a portion of the steering element. A plurality of injection ports may be disposed in the portion of the fluid injection tube contoured about the steering element.

Abstract: A medical device, including an elongate body having a proximal portion and a distal portion; a shaft at least partially disposed within the elongate body; an expandable element at the distal portion of the elongate body; and a fluid delivery conduit defining a deflectable segment movably coupled to the shaft, the deflectable segment being transitionable from a substantially linear configuration to a substantially curvilinear configuration.

Abstract: A medical device, including an elongate body having a proximal portion and a distal portion; a shaft at least partially disposed within the elongate body; an expandable element at the distal portion of the elongate body; and a fluid delivery conduit defining a deflectable segment movably coupled to the shaft, the deflectable segment being transitionable from a substantially linear configuration to a substantially curvilinear configuration.

Abstract: A medical system, comprising an ablation catheter is disclosed. The ablation catheter includes an elongate shaft with a proximal end, a distal end and a lumen disposed between the proximal end and the distal end. The ablation catheter also includes an expandable element in fluid communication with the lumen, a first temperature sensor operable to measure a first temperature; and a second temperature sensor operable to measure a second temperature. The first temperature sensor and the second temperature sensor are longitudinally separated from each other by at least a portion of the expandable element.

Abstract: A method and system for continuously delivering cryotreatment to a treatment device. In one embodiment, the system may include a first PID circuit in the fluid delivery line and a second PID circuit in the fluid return line, and the first and second PID circuits may operate simultaneously to continuously provide coolant to a cryotreatment device during the inflation phase, ablation phase, and warming (or thawing) phase while providing for temperature adjustment. Alternatively, the system may include a bypass line by which coolant may bypass the subcooler system and be delivered to the cryotreatment device at non-ablation temperatures during the inflation phase. During the ablation phase, coolant may flow through the subcooler system.

Abstract: A method and system for improved lesion creation. The method generally includes positioning a treatment element of a medical device proximate an area of target tissue and operating a control unit in accordance with a duty cycle, that includes at least one freeze-warm cycle, each freeze-warm cycle including: supplying coolant to the treatment element at a first flow rate that causes the treatment element to reach a first temperature, the first temperature causing ablation of the target tissue and cryoadhesion between the treatment element and target tissue, and supplying coolant to the treatment element at a second flow rate that causes the treatment element to reach a second temperature, the second temperature being higher than the first temperature and the second flow rate being lower than the first flow rate, the second temperature being above a temperature at which ablation occurs and below a temperature at which cryoadhesion is broken.

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: A method of treating tissue is provided, including positioning a stimulation device proximate a phrenic nerve; stimulating the phrenic nerve with the stimulation device; measuring a physiological response to the stimulation; defining a threshold physiological response value based at least in part on the measured physiological response; positioning a thermal treatment element proximate to an arrhythmogenic cardiac tissue region; applying a thermal treatment regimen to the cardiac tissue region with the medical device; measuring a physiological parameter during the thermal treatment regimen application; and conveying the measured physiological parameter to a controller, the controller comparing the measured physiological parameter to the defined physiological response value threshold, the controller adjusting the thermal treatment regimen in response to the comparison of the measured physiological parameter to the defined physiological response value threshold.

Abstract: An intravascular catheter is provided, including a flexible elongate body; an expandable element positioned on the elongate body; a substantially linear thermal segment located distally of the expandable element; a first fluid flow path in fluid communication with the expandable element; and a second fluid flow path in fluid communication with the substantially linear thermal segment.

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: A method of ablating tissue is provided, including positioning an expandable element of a catheter in a blood vessel; inflating the expandable element with a volume of refrigerant to substantially occlude the blood vessel; measuring the volume of refrigerant used to inflate the expandable element; correlating the measured volume to an inflated dimension of the expandable element; defining at least one of a target pressure within the expandable element and a target flow rate for refrigerant delivery to the expandable element based at least in part on the inflated dimension; regulating refrigerant delivery to the expandable element to attain the at least one defined target pressure within the expandable element or defined target flow rate for fluid delivery to the expandable element; and ablating at least a portion of the blood vessel with the expandable element.