Abstract: The invention relates to an ablation catheter which controls the temperature and reduces the coagulation of biological fluids on an electrode of a catheter, prevents the impedance rise of tissue in contact with the electrode, and maximizes the potential energy transfer to the tissue, thereby allowing an increase in the lesion size produced by the ablation. The electrode includes passages positioned to allow saline flow out of an inner cavity of the electrode. This fluid flow produces the desired cooling effect and is accomplished, for example, by saline irrigation flow with a valve element to block flow of blood into the inner cavity of the electrode.

Abstract: An ablating device has a cover which holds an interface material such as a gel. The cover contains the interface material during initial placement of the device. The ablating device may also have a removable tip or a membrane filled with fluid. In still another aspect, the ablating device may be submerged in liquid during operation.

Abstract: A method of identifying the fossa ovalis in a patient by positioning one or more electrodes against the tissue of the interatrial septum of the patient and acquiring unipolar and/or bipolar electrograms of the tissue of the interatrial septum while moving the electrodes to a plurality of positions against the tissue of the interatrial septum. The fossa ovalis is identified on the basis of unipolar voltage reduction, signal fractionation, broadened signal, reduced signal slew rate, reduced local myocardial impedance, increased phase angle and/or increased pacing threshold. An apparatus for identify the fossa ovalis is also provided.

Abstract: A method of repairing a three dimensional surface mesh model to be watertight and manifold generally includes identifying a plurality of hole edges in the surface mesh model, selecting one of the hole edges, creating a cycle of hole edges that defines a hole in the surface mesh model, converting the cycle of hole edges into two or more cycles of exactly three edges each, and adding a triangular facet to the surface mesh model for each of the cycles of exactly three edges. The process may be repeated until the model is substantially watertight. Non-manifold vertices may be repaired by selecting a vertex of the model, identifying a number of independent cycles of triangular facets sharing the selected vertex, and redefining the selected vertex for at least all but one of the number of independent cycles. This process may be repeated until the model is manifold.

Abstract: A wire lock includes a body having an opening therethrough, a locking member disposed at least partially within the opening, and a biasing device. The biasing device urges the locking member into a configuration wherein a wire passing through the opening is restrained in at least one direction, and may operate in either tension or compression. The locking member may include one or more locking elements that are compressed about the wire through engagement with a wedge-shaped locking section of the body, with the biasing member urging the locking member against the locking section. In other embodiments, the locking member is a locking pin riding on an inclined surface of an elongate slot extending across the body, with the biasing member urging the locking pin against one end of the slot, and the wire pinched between the pin and a body surface opposite the inclined surface.

Abstract: Catheter systems and methods are disclosed for anchoring the catheter system to tissue, e.g., for delivery of biologic or chemical agents, or other therapeutic fluid during various procedures. An exemplary tissue anchoring catheter comprises an outer catheter shaft connected to a catheter handle. A delivery sheath is provided within the outer catheter shaft, the delivery sheath housing a needle. At least one anchor is operatively associated with the delivery sheath, the at least one anchor operable at the catheter handle to secure the delivery sheath to tissue for conveying biologic or chemical agents, or other therapeutic fluid from the needle to the tissue. The tissue anchoring catheter may further comprise sensing means such as piezoelectric, pressure, thermistor, thermocouple, or ultrasound sensors.

Abstract: Disclosed herein are ablation systems and methods for providing feedback on lesion formation in real-time. The methods and systems assess absorptivity of tissue based on a degree of electric coupling or contact between an ablation electrode and the tissue. The absorptivity can then be used, along with other information, including, power levels and activation times, to provide real-time feedback on the lesions being created. Feedback may be provided, for example, in the form of estimated lesion volumes and other lesion characteristics. The methods and systems can provide estimated treatment times to achieve a desired lesion characteristic for a given degree of contact, as well as depth of a lesion being created. The degree of contact may be measured using different techniques, including the phase angle techniques and a coupling index.

Abstract: An ablation catheter including a shaft supporting one or more partially or completely exposed braided electrodes that may be positioned against a target tissue to ablate the tissue. The shaft may be precurved in a loop-like shape or any other shape to assist in positioning the electrode against a target tissue. The shaft may include a fluid lumen to direct a fluid material, which may be conductive, through one or more apertures or ports. The ports are adapted to direct the fluid past portions of the braided electrode to cool the electrode, flush blood away from the electrode, and to transfer ablation energy to the target tissue. Ablation energy may be delivered directly by the electrode and by way of a conductive fluid contacting the electrode. The shaft may further include a second lumen to provide a housing for a control wire that may be used to control the shape of the shaft.

Abstract: Side-port sheaths for catheter placement and translation are disclosed. The sheaths include a side-port opening through which a gliding catheter may be deployed during diagnosis or treatment of tissue. The side-port sheath may include a suspension ribbon used to deploy, or that aids in the deployment of, the embedded gliding catheter. The suspension ribbon may be slideably or fixably engaged with an outer surface of the sheath of the gliding catheter.

Abstract: System and methods are disclosed for tissue contact and thermal assessment, e.g. for tissue ablation procedures. An exemplary brush electrode comprises a plurality of flexible filaments adapted to transfer electrical energy to a tissue. At least one piezoelectric sensor is embedded among the plurality of flexible filaments. The at least one piezoelectric sensor is responsive to contact stress of the flexible filaments by generating electrical signals corresponding to the amount of contact stress. An output device is electrically connected to the at least one piezoelectric sensor. The output device receives the electrical signal for assessing tissue contact by the flexible filaments. The brush electrode may further comprise a sensing device mounted adjacent the at least one piezoelectric sensor, wherein the sensing device is a pressure sensor, a thermistor, a thermocouple, or an ultrasound sensor.

Abstract: A method of locating the fossa ovalis in a patient by locating the His bundle, plane of the interatrial septum, and coronary sinus ostium in a patient, and thereafter locating the fossa ovalis on the basis of one or more predetermined distances between the fossa ovalis and the His bundle and the coronary sinus ostium. An apparatus for locating the fossa ovalis and performing a transseptal puncture is also provided.

Abstract: Catheter navigation is coupled with ultrasound imaging to yield a context map showing the location on a heart of the ultrasonically imaged frame.

Abstract: An ablation catheter employing a continuous or nearly continuous flexible electrode arrangement. In one implementation, the flexible electrode include at least one electrode defining a saw tooth pattern. In another implementation, the flexible electrode is arranged in an interlaced pattern. Generally, the flexible electrodes are configured to adapt to the change in shape of the portion of the catheter that the electrode is connected with. Moreover, the flexible electrodes are arranged to provide a continuous or nearly continuous lesion of the target tissue. In some implementations, the flexible electrode may be connected with the catheter in a biased configuration, and as such may assist in changing the shape of a curve in the catheter.

Abstract: An ablation catheter has a virtual electrode tip including a fluid manifold structure for operably varying the active area of the virtual electrode. An array of apertures in the distal end of the catheter form the virtual electrode structure. A movable plug slides within the fluid manifold and seals against the interior walls of the fluid manifold. Conductive fluid cannot flow past the plug to fill the fluid manifold on the side of the plug opposite a fluid inlet channel into the fluid manifold. An electrode is positioned within the fluid manifold between the plug and the end wall of the fluid manifold adjacent the channel. By moving the plug within fluid manifold, only those portholes between the plug and the inlet channel will emit energized fluid. The effective length of an active ablation section of the virtual electrode is changed by repositioning the plug within the fluid manifold.

Abstract: The instant invention relates to an electrophysiology apparatus and method used to measure electrical activity occurring in a portion of tissue of a patient and to visualize the electrical activity and/or information related to the electrical activity. In particular, the instant invention relates to three-dimensional mapping of the electrical activity and/or the information related to the electrical activity.

Abstract: A catheter is designed with a virtual electrode structure for creating a linear lesion. The catheter includes a sensor array that measures temperatures of adjacent tissue along the length of the virtual electrode section. The sensors in the sensor array include a conductive material that is substantially coated with an electrically and thermally insulating material. An aperture is formed in the insulating coating to expose an area of the conductive material. Leads are coupled with each sensor and are connected at their opposite, proximal ends with a discrimination circuit. The circuit processes the signals induced in the sensors to output a single temperature measurement, for example, the highest temperature, the lowest temperature, or the average temperature. The sensors also measure cardiac electrical activity and the leads are further connected to an electrocardiograph monitor to determine the efficacy of treatment.

Abstract: An irrigated ablation catheter includes a tubular catheter body having an inner tubular member and an outer tubular member. The catheter body has a proximal portion and a distal portion. The catheter also includes an electrode extending from the distal portion of the catheter body, a flow distributor positioned at least partially within distal portion of the catheter body and at least partially overlapping the electrode, and a flow path extending through the catheter body and the flow distributor. The flow path is configured to provide cooling fluid to an external surface of the electrode.

Abstract: A device for both providing therapy to a tissue and detecting a characteristic of said tissue is provided. The device includes a deformable tubular body such as a catheter or scope. An electrode is supported by the body and configured to deliver therapeutic energy to the tissue along a first path. The electrode may, for example, be used in cardiac ablation and the therapeutic energy may comprise any common ablation energy modality including radio waves or ultrasound waves. The device further includes an acoustic transducer supported by the body and configured to receive acoustic energy along a second path. The transducer may also transmit acoustic energy. The first and second paths are aligned and may be parallel or overlap, for example. The physical relationship of the electrode and transducer and the alignment of the energy paths eliminates the need to register the spatial coordinates of the therapeutic and diagnostic elements.

Abstract: A method and apparatus for mapping a location of a point within the body is disclosed. A plurality of positional reference nodes are determined, each aligned on a first element. A second element is mapped with reference to the plurality of reference nodes to determine the relative location of a point on the second element.

Abstract: The invention relates to a steerable catheter having a distal section with reduced variation in deflection path during deflection. The distal section of the catheter includes stripes of different material hardness along the length of the distal section affecting the directionality of catheter deflection upon the application of a deflection force like that applied by pull wires. The stripes result in preferential bending in a desired path with greater reproducibility.