Abstract: Systems and methods are disclosed for assessing electrode-tissue contact for tissue ablation. An exemplary electrode contact sensing system comprises an electrode 10 housed within a distal portion of a catheter shaft 14. At least one electro-mechanical sensor 20 is operatively associated with the electrode 10 within the catheter shaft 14. The at least one electro-mechanical sensor 20 is responsive to movement of the electrode 10 by generating electrical signals corresponding to the amount of movement. The system may also include an output device electrically connected to the at least one electro-mechanical sensor 20. The output device receives the electrical signals for assessing a level of contact between the electrode 10 and a tissue 12.

Abstract: Catheter systems include direction-sensitive, multi-polar tip electrode assemblies for electroporation-mediated therapy, electroporation-induced primary necrosis therapy and electric field-induced apoptosis therapy, including configurations for producing narrow, linear lesions as well as distributed, wide area lesions. A monitoring system for electroporation therapy includes a mechanism for delivering electrochromic dyes to a tissue site as well as a fiber optic arrangement to optically monitor the progress of the therapy as well as to confirm success post-therapy. A fiber optic temperature sensing electrode catheter includes a tip electrode having a cavity whose inner surface is impregnated or coated with thermochromic/thermotropic material that changes color with changes in temperature. An optic fiber/detector arrangement monitors the thermochromic or thermotropic materials, acquiring a light signal and generating an output signal indicative of the spectrum of the light signal.

Abstract: An electrode for ablation therapy includes a flexible conductive element for conducting electrical energy and a flexible conductive polymer member in electrically conductive contact with the conductive element. A catheter shaft may be coupled to the conductive element and/or the flexible conductive polymer member. The flexible conductive element may be formed as a helical coil, a mesh coating or wrap, or any other suitable form, and may surround (wholly or partially) a flexible electrically insulative, and optionally thermally conductive, member. A heat sink may be thermally coupled to at least one of the flexible conductive polymer member and the flexible electrically insulative member. The flexible electrically insulative member may include a passageway for coolant fluid to cool the electrode during ablation. The passageway may include at least one efflux hole to permit coolant fluid to flow from the passageway, or may define a closed loop.

Abstract: A catheter is disclosed having a flexible tubing with a proximal end and a distal end. The catheter comprising at least one movable magnet provided within the distal end of the flexible tubing. A control mechanism is operable to selectively activate the at least one movable magnet from the proximal end of the flexible tubing. The at least one movable magnet is responsive to an external magnetic field to position and guide the distal end of the flexible tubing within a body of a patient.

Abstract: A method and system for presenting information representative of lesion formation is provided. The system comprises an electronic control unit (ECU). The ECU is configured to acquire a value for an ablation description parameter and/or a position signal metric, wherein the value corresponds to a location in the tissue. The ECU is further configured to evaluate the value, assign it a visual indicator of a visualization scheme associated with the parameter/metric corresponding to the value, and generate a marker comprising the visual indicator such that the marker is indicative of the acquired value. The method comprises acquiring a value for the parameter/metric, and evaluating the value. The method further includes assigning a visual indicator of a visualization scheme associated with the parameter/metric corresponding to the value, and generating a marker comprising the visual indicator.

Abstract: A monitoring, managing and protecting system is provided that includes a monitoring probe working in conjunction with an ablating device. The probe is configured to be positioned in close proximity to a region of non-targeted tissue proximate an ablation site of targeted tissue and to be operatively connected to an electrical response assessment system or component. The probe includes an elongate shaft having proximal and distal ends, with a handle disposed at the proximal end thereof and a tissue monitoring and protecting apparatus disposed at the distal end thereof. The ablating device includes an elongate shaft having proximal and distal ends, with a handle mounted at the proximal end thereof and an ablation element mounted at the distal end thereof. The monitoring probe measures electrical characteristics of the non-targeted tissue and/or of the tissue between the monitoring electrode and the ablation electrode.

Abstract: A transseptal medical device (10, 110) is provided including a dilator (12, 112), a needle (14, 114), and a needle control mechanism (22, 122). The needle (14, 114) may be disposed within the dilator (12, 112), and the needle control mechanism (22, 122) may be operably connected to a proximal end (24, 124, 16, 116) of the needle (14, 114) or the dilator (12, 112) for selective adjustment of the distal end (26, 126) of the needle (14, 114) from a first position within the dilator (12, 112) to a second position external to the dilator (12, 112). The needle control mechanism (22) may include an actuator (32) configured for rotation within the dilator in one embodiment.

Abstract: A contact sensing assembly including a catheter and an electrode including a tip portion and a base portion, and a generally central axis, with the electrode being connected to a distal end of the catheter. Optical sensor(s) may be provided for emitting and/or receiving an optical signal, with a part of the optical signal being transverse to the central axis. Optical interference member(s) may be provided for interfering with the optical signal. A method for sensing contact force exerted by an electrode on a tissue includes directing an optical signal along a portion of a catheter, emitting and/or receiving an optical signal, with a part of the optical signal being at a predetermined angle relative to the central axis, and sensing changes in intensity of the optical signal based on displacement associated with the electrode tip portion based on the contact force exerted by the electrode on the tissue.

Abstract: A method and system for determining tissue type is provided. The system comprises an electronic control unit (ECU) configured to acquire a value of an electrical parameter between a first electrode electrically coupled with tissue and a second electrode. The ECU is further configured to identify a tissue type from a plurality of tissue types based at least on the acquired value, and in an exemplary embodiment, to generate a tissue morphology map comprising a marker representative of the identified tissue type. The method comprises acquiring a value of an electrical parameter between a first electrode electrically coupled with tissue and a second electrode. The method further comprises identifying a tissue type from a plurality of tissue types based on at least the acquired value of the electrical parameter, and in an exemplary embodiment, the method further comprises generating a tissue morphology map based on the identified tissue type.

Abstract: Systems and methods are disclosed for assessing electrode-tissue contact for tissue ablation. An exemplary electrode contact sensing system comprises an electrode housed within a distal portion of a catheter shaft. At least one electro-mechanical sensor is operatively associated with the electrode within the catheter shaft. The at least one electro-mechanical sensor is responsive to movement of the electrode by generating electrical signals corresponding to the amount of movement. The system may also include an output device electrically connected to the at least one electro-mechanical sensor. The output device receives the electrical signals for assessing a level of contact between the electrode and a tissue.

Abstract: Systems and methods for photodynamic ablation of cardiac tissue via an esophagus are disclosed. An exemplary system includes an ablation catheter having an expandable distal end for securing the ablation catheter in the esophagus. The distal end of the ablation catheter contains at least one light source operable to activate a photodynamic substance delivered to the target area of the cardiac tissue to be ablated and form a lesion. The system also includes at least one feedback device contained in the distal end of the ablation catheter. The at least one feedback device provides feedback for at least one of: positioning a distal end of an ablation catheter in a desired position in the esophagus adjacent a target area of the cardiac tissue to be ablated, forming an adequate lesion, and assessing lesion formation.

Abstract: Acoustic coupling systems and methods are disclosed as these can be used for assessment and ablation procedures. An exemplary acoustic assessment system for a catheter may comprise a flexible catheter shaft. At least one acoustic transducer is positioned in the flexible catheter shaft. The at least one acoustic transducer emits a generated acoustic signal for reflection by adjacent tissue. The at least one acoustic transducer receives a reflected acoustic signal from the adjacent tissue and generates electrical signals corresponding to one or more property of the tissue. An output device is electrically connected to the at least one acoustic transducer. The output device receives the electrical signals and generate output for a user for assessing the tissue.

Abstract: A method and system for determining a likelihood of barotrauma occurring in tissue during the formation of a lesion therein is provided. The system includes an electronic control unit (ECU). The ECU is configured to acquire at least one value of at least one component of a complex impedance between an electrode and the tissue. The ECU is further configured to calculate an index responsive to the at least one value of the at least one complex impedance component. The index is indicative of a likelihood of barotrauma occurring in the tissue. The method comprises acquiring at least one value of at least one component of a complex impedance between an electrode and the tissue. The method further comprises calculating an index responsive to the at least one value of the at least one complex impedance component. The calculating index is indicative of a likelihood of barotrauma occurring in the tissue.

Abstract: The present invention is directed to ablation devices and methods utilizing pressure sensitive conductive composites, such as quantum tunneling composites, or other contact-sensitive, conductive polymers. The materials provide for electrodes and methods capable of differentiating between a soft and a hard push. The present invention thus provides an electrode for delivering selective electrical energy for ablation that may be varied based upon the pressure exerted on the surface area of the targeted tissue.

Abstract: A method and system for assessing lesion formation in tissue is provided. The system includes an electronic control unit (ECU) configured to acquire magnitudes for a component of a complex impedance between an electrode and tissue, and the power applied to the tissue during lesion formation. The ECU is configured to calculate a value responsive to the complex impedance component and the power. The value is indicative of a predicted lesion depth, a likelihood the lesion has reached a predetermined depth, or a predicted tissue temperature. The method includes acquiring magnitudes for a component of a complex impedance between an electrode and tissue and the power applied during lesion formation. The method includes calculating a value responsive to the complex impedance component and the power, the value being indicative of a predicted lesion depth, a likelihood the lesion has reached a predetermined depth, and/or a predicted tissue temperature.

Abstract: A catheter assembly for pressure-sensitive control of ablation treatment is disclosed. The assembly includes a conductive element, an electrode, and a pressure sensitive conductive composite member positioned between the conductive element and the electrode. At least one of the conductive pin, the pressure sensitive conductive composite element and the ablation electrode are moveable to create an engagement position and a non-engagement position. In the engagement position, the elements are electrically coupled such that ablation energy may be delivered from the conductive pin to the ablation electrode via the pressure sensitive conductive composite element. In the non-engagement position, the elements are electrically decoupled such that ablation energy is not delivered to the ablation electrode. A related method for pressure-sensitive control of ablation is also disclosed.

Abstract: A photodynamic mapping device includes a shaft with a proximal end and a distal end, at least one optical electrode at the distal end of the shaft, and at least one optical fiber positioned inside the shaft. In embodiments, the at least one optical fiber extends from the distal end of the shaft and is coupled to the at least one optical electrode provided at or about an outer surface of the device. In an embodiment, at least one optical fiber is coupled, at or about the proximal end of the shaft, to a light source coupled and an optical sensor. An analyzer can be coupled to the optical sensor. Embodiments of such devices can be configured to deliver substances, such as photodynamic therapeutic substances.

Abstract: Virtual-electrode catheters and methods for using such virtual-electrode catheters are disclosed. For example, bipolar and multipolar, virtual-electrode catheters having at least one internal electrode and at least one surface electrode, and methods of using these catheters for treatment of cardiac arrhythmias via, for example, radiofrequency (RF) ablation are disclosed. The catheters may comprise a catheter body with an internal lumen extending within it and adapted to flowingly receive a conductive fluid. An exit feature defining a flow path from the internal lumen to the catheter's outer surface may exist through a sidewall of the catheter body. A conductor is mounted within the internal lumen adjacent to the exit feature and is adapted to deliver treatment energy to the tissue via the conductive fluid in the internal lumen. At least one surface electrode is mounted on the outer surface of the catheter body adjacent to the exit feature.

Abstract: A catheter assembly for assessing contact between the catheter assembly and tissue is disclosed. In an exemplary embodiment the assembly includes a catheter shaft and a trio of pressure sensitive capacitive members each of whose electrical resistance varies with a pressure vector applied to the catheter assembly. The assembly also includes at least one measurement terminal to permit the measurement of changes in the electrical characteristics of the pressure sensitive capacitive members. The assembly may optionally include a measurement device to measure resistance, impedance and/or other electrical characteristics. The assembly may utilize a reference electrode secured to the patient's tissue, which permits the measurement device to measure changes between the reference electrode and the at least one measurement terminal. Optionally, the assembly may include a conductive outer layer.

Abstract: An electrode catheter and a method for assessing electrode-tissue contact and coupling are disclosed. An exemplary electrode catheter comprises an electrode adapted to apply electrical energy. A measurement circuit is adapted to measure impedance between the electrode and ground as the electrode approaches a target tissue. A processor determines a contact and coupling condition for the target tissue based at least in part on reactance of the impedance measured by the measurement circuit. In another exemplary embodiment, the electrode catheter determines the contact and coupling condition based at least in part on a phase angle of the impedance.