Abstract: A catheter having an extended treatment zone for cooling tissue is provided. The catheter includes an elongate catheter body having a distal tip, and a fluid injection conduit disposed inside the catheter body defining a return lumen therein. The fluid injection conduit further defines two or more injection orifices including a first distal orifice near the distal tip, and a second orifice longitudinally offset along the fluid injection conduit to be less proximate the distal tip than the first orifice. Fluid cryogen flowing through the orifices creates an extended tissue cooling contour about the distal end portion of the catheter. At least one ECG ring electrode is provided about the catheter body near the second orifice. The catheter may thus provide for electrocardiographic mapping of tissue nodes lying transversely between the distal tip and the ECG ring electrode.

Abstract: An elongated catheter device with a distal balloon assembly is adapted for endovascular insertion. Coolant injected through the device may, in different embodiments, directly cool tissue contacting the balloon, or may cool a separate internal chamber. Plural balloons may be provided, wherein a secondary outer balloon surrounds a primary inner balloon, the primary balloon being filled with coolant and acting as the cooling chamber, the secondary balloon being coupled to a vacuum return lumen to serve as a robust leak containment device and thermal insulator around the cooling chamber. One or more sensors may be disposed between the balloons or the vacuum return lumen, to detect leaks and control the flow of fluid through the device. Examples of sensors include pressure and temperature sensors, optical sensors, magnetic flow switches and flow meters.

Abstract: A method of treating tissue is provided, including positioning a portion of a catheter in proximity to cardiac tissue; measuring an impedance value with the catheter; determining a respiratory rate based at least in part on the measured impedance value; and thermally treating the cardiac tissue with the catheter.

Abstract: An elongated catheter device with a distal balloon assembly is adapted for endovascular insertion. Coolant injected through the device may, in different embodiments, directly cool tissue contacting the balloon, or may cool a separate internal chamber. Plural balloons may be provided, wherein a secondary outer balloon surrounds a primary inner balloon, the primary balloon being filled with coolant and acting as the cooling chamber, the secondary balloon being coupled to a vacuum return lumen to serve as a robust leak containment device and thermal insulator around the cooling chamber. One or more sensors may be disposed between the balloons or the vacuum return lumen, to detect leaks and control the flow of fluid through the device. Examples of sensors include pressure and temperature sensors, optical sensors, magnetic flow switches and flow meters.

Abstract: The present invention provides a medical system including a protective sleeve for a medical device having a distal end positionable in a blood vessel, the protective sleeve including a body defining a passage therethrough and a vent in fluid communication with the passage, where at least a portion of the distal end of the medical device is positionable within the passage. An introducer device may be included having a sheath, where the sheath defines a first passage for receiving a portion of the catheter. In addition, the sleeve may be releasably engageable with the introducer device for subsequent insertion of the medical device into the introducer device.

Abstract: A system and method for controlling the inflation, ablation, and deflation of a balloon catheter. The system includes a balloon catheter, a console, a pressurized gas or liquid inflation source, and an umbilical system to deliver pressurized coolant to the balloon catheter. The system may include controller that monitors the amount of pressure and volume within the balloon catheter. During inflation, the pressure and/or volume of fluid within the balloon is maintained at a target amount in order to provide sufficient mechanized pressure against the desired target region. The system limits the inflation pressure such that a safe quantity of gas would be released should a leak occur. If the amount falls below a certain threshold level, gas or fluid egress is presumed and the inflation process is halted.

Abstract: A medical apparatus and system for determining contact assessment includes a catheter having an elongate body having a proximal end, a distal end opposite the proximal end, and defining an injection lumen and an exhaust lumen, an expandable membrane defining a cooling chamber disposed at a point along the elongate body, the cooling chamber in fluid communication with the injection lumen and the exhaust lumen, and a contact assessment element which may be a temperature sensor located proximate the coolant return lumen for measuring an internal temperature of the chamber. The system may include the catheter, a console having a fluid supply, an exhaust path and at least one control mechanism operationally coupled to the temperature sensor for processing a temperature signal received from the temperature sensor. The apparatus and system can also have multiple electrodes to measure and process various impedances to determine contact assessment.

Abstract: A tissue ablation system for ablating tissue is presented having independent sensing and ablation capabilities. A sensing wire is positioned distally to the ablation region and passed through the ablation device allowing independent movement. The ablation device can ablate a substantial portion of a circumferential region of tissue. The tissue ablation system comprises an ablation device comprised of an elongated catheter with a proximal region and a distal region and an ablation element located proximate the distal region of the catheter. A sensing device having an elongated body with a proximal portion and a distal portion is adapted to be positioned within a vessel at or near a vessel ostium, wherein the sensing device is adapted to be slidably received within a lumen of the ablation device. The sensing device may be shaped in various configurations.

Abstract: A tissue ablation system for ablating tissue is presented having independent sensing and ablation capabilities. A sensing wire is positioned distally to the ablation region and passed through the ablation device allowing independent movement. The ablation device can ablate a substantial portion of a circumferential region of tissue. The tissue ablation system comprises an ablation device comprised of an elongated catheter with a proximal region and a distal region and an ablation element located proximate the distal region of the catheter. A sensing device having an elongated body with a proximal portion and a distal portion is adapted to be positioned within a vessel at or near a vessel ostium, wherein the sensing device is adapted to be slidably received within a lumen of the ablation device. The sensing device may be shaped in various configurations.

Abstract: A catheter includes a cryoablation tip with an electrically-driven ablation assembly for heating tissue. The cryoablation tip may be implemented with a cooling chamber through which a controllably injected coolant circulates to lower the tip temperature, and having an RF electrode at its distal end. The RF electrode may be operated to warm cryogenically-cooled tissue, or the coolant may be controlled to conductively cool the tissue in coordination with an RF treatment regimen, allowing greater versatility of operation and enhancing the lesion size, speed or placement of multi-lesion treatment or single lesion re-treatment cycles. In one embodiment a microwave energy source operates at a frequency to extend beyond the thermal conduction depth, or to penetrate the cryogenic ice ball and be absorbed in tissue beyond an ice boundary, thus extending the depth and/or width of a single treatment locus.

Abstract: A method and system for determining contact assessment includes the steps of positioning a catheter at a tissue treatment site, where the catheter has a proximal end portion and a distal end portion, the proximal end portion defining at least one fluid inlet port and at least one fluid outlet port, an expandable membrane defining a cooling chamber a coolant injection lumen in fluid communication with the at least one fluid inlet port and the cooling chamber, a coolant return lumen in fluid communication with the at least one fluid outlet port and the cooling chamber, the coolant injection tube, the cooling chamber, and the primary coolant return lumen defining a fluid pathway and a temperature sensor located near the coolant return lumen; measuring an internal temperature of the chamber, and modifying the position of the catheter in response to the measured temperature. The method and system can also use a measured impedance to determine contact assessment.

Abstract: The present invention provides a medical device having an elongate body with both a proximal end and a distal end, wherein the elongate body defines an intake lumen and an exhaust lumen. The medical device also has a first pliable element defining a cooling chamber disposed at a point along the elongate body, with the cooling chamber being in fluid communication with the intake lumen and the exhaust lumen. A second pliable element is provided which at least partially encloses the first pliable element, thereby defining a junction between the first and second pliable element. Moreover, a check valve is included which is in fluid communication with the junction between the first pliable element and second pliable element, the valve further being in fluid communication with the exhaust lumen. In addition, the medical device may include sensors or other monitoring means in fluid communication with the junction and the cooling chamber.

Abstract: The present invention advantageously provides a method and system for cryogenically ablating large areas of tissue within the left atrium. In an exemplary embodiment a cryotherapy device includes a catheter body having a substantially fixed diameter, a proximal end and a distal end; a first lumen for permitting passage of a cooling fluid from the proximal end to the distal end; a second lumen permitting return of the cooling fluid from the distal end to the proximal end; and an ablation element expandable from a first diameter that is substantially the same as the diameter of the catheter body to a second diameter that is at least twice the diameter of the catheter body, the ablation element having a surface portion that conforms to the uneven surface topography of the cardiac tissue. The ablation element can include one or more balloon and/or a flexible element that is deformed by moving the distal end of the catheter toward the proximal end of the catheter.

Abstract: Methods and systems for detecting fluid egress, assessing lesion quality, determining tissue composition or structure, determining ice coverage of catheter tip and providing tissue contact assessment, by providing a catheter having a shaft with a proximal end portion and a distal end portion, the proximal end portion and the distal end portion define at least one fluid pathway therebetween with the shaft having a plurality of electrodes, positioning the catheter at a tissue treatment site, applying an electrical current between at least two of the plurality of electrodes, measuring impedance voltage between the at least two of the plurality of electrodes and, processing the measured impedance voltage caused by the applied electrical current to determine if fluid egress is present, to assess lesion quality, to determine tissue composition, ice cover of catheter tip, and to provide contact assessment.

Abstract: Methods and systems for detecting fluid egress, assessing lesion quality, determining tissue composition or structure, determining ice coverage of catheter tip and providing tissue contact assessment, by providing a catheter having a shaft with a proximal end portion and a distal end portion, the proximal end portion and the distal end portion define at least one fluid pathway therebetween with the shaft having a plurality of electrodes, positioning the catheter at a tissue treatment site, applying an electrical current between at least two of the plurality of electrodes, measuring impedance voltage between the at least two of the plurality of electrodes and, processing the measured impedance voltage caused by the applied electrical current to determine if fluid egress is present, to assess lesion quality, to determine tissue composition, ice cover of catheter tip, and to provide contact assessment.

Abstract: A surgical device includes a device body defining a sealed fluid path having a first end and a second end, a refrigerant supply in communication with the first end of the sealed fluid path, and a vacuum source in communication with the second end of the sealed fluid path. Leak detection apparatus can be provided in communication with the sealed fluid path.

Abstract: A catheter includes a cryoablation tip with an electrically-driven ablation assembly for heating tissue. The cryoablation tip may be implemented with a cooling chamber through which a controllably injected coolant circulates to lower the tip temperature, and having an RF electrode at its distal end. The RF electrode may be operated to warm cryogenically-cooled tissue, or the coolant may be controlled to conductively cool the tissue in coordination with an RF treatment regimen, allowing greater versatility of operation and enhancing the lesion size, speed or placement of multi-lesion treatment or single lesion retreatment cycles. In one embodiment a microwave energy source operates at a frequency to extend beyond the thermal conduction depth, or to penetrate the cryogenic ice ball and be absorbed in tissue beyond an ice boundary, thus extending the depth and/or width of a single treatment locus.

Abstract: The present invention advantageously provides a method and system for cryogenically ablating large areas of tissue within the left atrium. In an exemplary embodiment a cryotherapy device includes a catheter body having a substantially fixed diameter, a proximal end and a distal end; a first lumen for permitting passage of a cooling fluid from the proximal end to the distal end; a second lumen permitting return of the cooling fluid from the distal end to the proximal end; and an ablation element expandable from a first diameter that is substantially the same as the diameter of the catheter body to a second diameter that is at least twice the diameter of the catheter body, the ablation element having a surface portion that conforms to the uneven surface topography of the cardiac tissue. The ablation element can include one or more balloon and/or a flexible element that is deformed by moving the distal end of the catheter toward the proximal end of the catheter.

Abstract: The present invention advantageously provides a method and system for cryogenically ablating large areas of tissue within the left atrium. In an exemplary embodiment a cryotherapy device includes a catheter body having a substantially fixed diameter, a proximal end and a distal end; a first lumen for permitting passage of a cooling fluid from the proximal end to the distal end; a second lumen permitting return of the cooling fluid from the distal end to the proximal end; and an ablation element expandable from a first diameter that is substantially the same as the diameter of the catheter body to a second diameter that is at least twice the diameter of the catheter body, the ablation element having a surface portion that conforms to the uneven surface topography of the cardiac tissue. The ablation element can include one or more balloon and/or a flexible element that is deformed by moving the distal end of the catheter toward the proximal end of the catheter.

Abstract: A coolant system for a cryoablation or treatment probe such as a mapping or ablation catheter, or a treatment wand, includes a compressor and condenser having a low pressure inlet side and a high pressure outlet side, wherein the outlet side passes through a heat exchanger and is cooled by the inlet side and conditioned for injection to a catheter inlet. A vacuum return system connectable to the catheter outlet draws thermally expended coolant from the catheter and returns it to the low pressure inlet side. A motorized pressure regulator between the heat exchanger and the catheter inlet determines the pressure of coolant passing into the catheter and thus regulates the cooling rate for a selected mapping or ablation regimen. The low pressure compressor inlet supply preferentially conditions the pressurized coolant to ambient temperature or lower before injection into the catheter, allowing the coolant to travel through the body at ambient before expansion in the tip.