Abstract: An electrical stimulation lead includes a lead body that defines an alignment feature extending distally from a proximal end of the lead body and inwardly from an outer surface of the lead body. The lead also includes electrodes disposed along the distal portion of the lead body, segmented terminals disposed along the proximal portion of the lead and arranged in sets of segmented terminals, and lead conductors electrically coupling the electrodes to the terminals. Each set of segmented terminals includes at least two segmented terminals disposed in a circumferential arrangement at a same longitudinal position of the lead. A system can include the lead and a connector for receiving the proximal end of the lead. The connector can include an alignment protuberance extending into a connector lumen and configured to be received into the alignment groove of the lead to align the lead with the connector.

Abstract: Various aspects of the present disclosure are directed toward methods, apparatuses, and systems that include an implantable medical device comprising an implantable lead, a suture sleeve having an interior surface defining a lumen of the suture sleeve that receives the implantable lead, and an engagement feature configured to non-removeably secure the suture sleeve to the implantable lead.

Abstract: Embodiments of the invention include a temporarily or permanently implantable medical device with an elongate electrical line, and a method of producing the implantable medical device. The elongate electrical line includes a first electrical component and a second component, wherein the first electrical component or part of the first electrical component includes a functional conductor. The second component includes at least one metal layer and at least one flexible plastic layer. The first electrical component is electrically connected in series to the at least one metal layer of the second component.

Abstract: A cable for use in biopotential measurements in a magnetic resonance (MR) environment comprises a flexible plastic or polymer sheet (32, 40) extending as a single unitary structure from a first end to an opposite second end, and an electrically conductive trace (38, 58) disposed on the flexible plastic or polymer sheet and running from the first end to the opposite second end. The electrically conductive trace has sheet resistance of one ohm/square or higher, and may have a hatching or checkerboard pattern. The cable may further include an electrically insulating protective layer (50, 70) disposed on the substrate and covering the electrically conductive trace, an electrode (30) disposed on the electrically conductive trace at the second end, an edge connector (74) at the first end, or various combinations of such features.

Abstract: A microlead has a distal active portion formed by a microcable including an electrically conductive core coated with an insulation layer, with a plurality of exposed areas forming the stimulation electrodes. The microcable has a three-dimensional preshape inscribed in a cylindrical envelope volume so as to match the target vessel wall. The microcable includes a plurality of exposed areas regularly distributed over the circumference of the cylindrical envelope volume considered in axial projection, the exposed zones extending only over an angular sector of the microcable considered in cross section, said angular sector facing the outside of the envelope volume of the preshape.

Abstract: The invention relates to a catheter (10a), comprising a flexible catheter body (10a) forming at least two hollow spaces (90, 100/110) along the longitudinal extension thereof, characterized in that the catheter body (10a) comprises at least two consecutively arranged sections (20) having sheaths (60) that are arranged between the sections (20) and seal the hollow spaces (90, 100/110) at least in some sections, wherein the one hollow space (90) is designed so it communicates with at least one opening (70) penetrating the catheter wall in each section (20), and the other hollow space (100/110) is equipped to introduce an element (40/50) that brings about a longitudinal change of at least one of the sections (20).

Abstract: Intravascular devices, systems, and methods are disclosed. In some embodiments, a method of assembling an intravascular device is provided that includes positioning a first tubular member around a plurality of conductors and a core member; advancing a first of the plurality of conductors through an opening of the first tubular member; positioning a first conductive member around the first tubular member; and electrically coupling the first of the plurality of conductors to the first conductive member. In some embodiments, an intravascular device is provided that includes an insulating member positioned around a plurality of conductors and a core member and a conductive member positioned around the insulating member, wherein at least one of the plurality of conductors extends through an opening in the insulating member and is electrically coupled to the first conductive member.

Abstract: Treatment of cardiac tissue via an implantable heart treatment device is described. A device embodiment includes, but is not limited to, a substrate configured for implantation within a body; an electromagnetic signal generator coupled to the substrate and configured to generate one or more electric signals configured to stimulate one or more tissues of a heart; and an oxygenator coupled to the substrate and configured to supply one or more oxygenated molecules to one or more tissues of the heart, the oxygenator including a blood inlet portion, a blood outlet portion, and an oxygen exchange portion positioned between the blood inlet portion and the blood outlet portion, the oxygen exchange portion including a high surface area oxygen exchanger configured to transfer one or more oxygenated molecules from the high surface area oxygen exchanger to blood passing from the blood inlet portion to the blood outlet portion.

Abstract: In one embodiment, a neurostimulation lead comprises: a lead body comprising a plurality of conductor wires; and a molded stimulation tip end comprising a plurality of segmented electrodes, hypotubes, and an annular frame structure: wherein (i) each segmented electrode of the plurality of segmented electrodes has an inner surface, an outer surface, and step-down region embedded within polymer material of the molded stimulation tip end, (ii) each respective hypotube is directly welded to the inner surface of a corresponding segmented electrode of the plurality of segmented electrodes.

Abstract: A catheter apparatus comprises an elongated catheter body having a distal end, a proximal end, and at least one fluid lumen extending longitudinally therein; and a plurality of flexible electrode segments on a distal portion of the catheter body adjacent the distal end, each pair of neighboring flexible electrode segments being spaced from each other longitudinally by a corresponding electrically nonconductive segment. Each flexible electrode segment comprises a sidewall provided with one or more elongated stiffness reductions extending through the sidewall, the one or more elongated stiffness reductions providing flexibility in the sidewall for bending movement relative to a longitudinal axis of the catheter body. The electrically nonconductive segment is substantially smaller in length than each of the corresponding pair of neighboring flexible electrode segments.

Abstract: A therapy lead has a distal header, a helix-shaft assembly, and a ring seal. The distal header has a cylindrical passage, and the helix-shaft assembly has a shaft and a helical anchor distally extending from the shaft. The shaft extends through the cylindrical passage. The ring seal circumferentially extends about the shaft and inside the cylindrical passage. The ring seal has a proximal face, a distal face, an outer circumferential surface, an inner circumferential surface, and a side wall. The distal face is opposite the proximal face. The outer circumferential surface extends between the proximal face and distal face. The inner circumferential surface is opposite the outer circumferential surface and extends between the proximal face and distal face. The inner circumferential surface defines a center hole of the ring seal that extends between the proximal face and distal face.

Abstract: The present invention's goal is to devise an apparatus (here-forth called ‘punch-ball’) made of a tension-reversible membrane that will assume a particular three-dimensional predetermined shape when under tension, apparatus that will border a central empty space, central space limited by the interior face of the membrane, and central space that will be in direct communication with the exterior space outside of the external face of the ‘punch-ball’ through orifices in the membrane (here-forth called ‘punches’), punches that will not decrease the ability of the membrane to exhibit a tension force. The punch-ball can be used freestanding or in connection with an object representing a confined space that will be abutting the exterior face of the punch-ball when the punch-ball is under tension.

Abstract: A coiled, closed-loop RF current attenuator is configured to be placed about an implantable lead conductor. A coiled conductor extends in a coiled shape defining a longitudinal axis from a first coil end to a second coil end. The first coil end is electrically connected to the second coil end. An insulator is disposed about the coiled conductor. The closed loop attenuator can also include in series a short, a capacitor and/or a resistor. In some embodiments the closed loop attenuator can be resonant at an MRI RF-pulsed frequency. The closed loop attenuator can be integrated as a permanent part of an implantable lead conductor, or alternatively, be a stand-alone device that is placed about a premade implantable lead conductor.

Abstract: Guidewires and methods for transmitting electrical stimuli to a heart and for guiding and supporting the delivery of elongate treatment devices within the heart are disclosed. A guidewire can comprise an elongate body, including first and second elongate conductors, and at least first and second electrodes. A distal end portion of the elongate body can include a preformed bias shape, such as a pigtail-shaped region, on which the first and second electrodes can be located. The preformed bias shape can optionally be non-coplanar relative to an intermediate portion of the elongate body. The first and second elongate conductors can be formed of a single structure or two or more electrically connected structures. The conductors can extend from proximal end portions to distal end portions that electrically connect to the first and second electrodes.

Abstract: Devices, systems, and methods for the localization of body lumen junctions and other intraluminal structure are disclosed. Various embodiments permit clinicians to identify the locations of intraluminal structures and medical devices during non-surgical medical techniques, such as cardiac ablation, by determining the intralumen conductance and/or cross-sectional area at a plurality of locations within the body lumen.

Abstract: Ablation catheter comprising an elongate member with proximal and distal ends, wherein the distal end is arranged to apply a high energy electrical shock from a plurality of locations along the length of said distal end and wherein said distal end is curved. Preferably the distal end of the elongate member extends in a circle segment.

Abstract: A device for positioning an electrode in tissue includes: a lead body having a distal portion; an electrode array coupled to the lead distal portion; an anchoring element having an anchor tip and being operable in a first configuration in which the anchor tip is retracted within the lead and in a second configuration in which the anchor tip is extended outside the lead and configured to fixate within the tissue; and a displacement mechanism that is actuated to bias the electrode array or the anchoring element toward the tissue. A method for positioning an electrode in tissue includes: navigating, to the tissue, a lead with an electrode array, an anchoring element with a distal anchor tip, and a displacement mechanism; biasing the electrode array and anchoring element towards the tissue with the displacement mechanism; and deploying the anchoring element, and verifying fixation of the anchor tip within the tissue.

Abstract: A medical device for conducting electrical signal comprises an elongate member and a plurality of cables. Each cable may have three concentric layers: a first layer with an inner conductor, a second layer with an inner insulator, and a third layer with an outer conductor. The inner insulator electrically isolates the outer conductor from the inner conductor.

Abstract: A medical device lead. The lead includes one or more jacketed conductive elements. The jacket comprises one or more covers. A first cover of polyether ketone (PEEK) is in direct contact with the at least one conductive element. At least one conductive element and a PEEK cover are coiled. The coiled conductive element can substantially retain its original coiled shape.

Abstract: An implantable lead assembly is provided that comprises a lead body having a proximal end portion and a distal end portion, and having a length extending there between. A plurality of electrodes are disposed along the lead body. A plurality of cable conductors are contained within the lead body, the conductors extending from the electrodes to the proximal end portion. A lead connector is provided at the proximal end portion. The lead connector includes a connector pin configured to mate with a corresponding header contact; a first termination pin coupled to one of the plurality of cable conductors; a collar coupler securely and electrically coupling the connector pin and first termination pin in an axially offset alignment with one another; and a body segment that is elongated along a longitudinal axis and extends between a header mating face and a lead mating end.

Abstract: An extensible medical lead comprises at least one proximal contact, at least one distal electrode, and having at least one conductive filer electrically coupled between the proximal contacts and the distal stimulation electrode. The lead further comprises an outer jacket made of a longitudinally compressible material. The conductive filer may also be coiled to provide extensibility.

Abstract: The present invention comprises articles and methods for atraumatic removal of a chronically implanted medical device, such as a vascular graft. Specifically, the invention comprises a thin, lubricious and durable tubular cover that aids in protecting the indwelling implant during implantation while also acting as an atraumatic removal aid.

Abstract: An integrated catheter placement system for accurately placing a catheter within a patient's vasculature is disclosed. In one embodiment, the integrated system comprises a system console, a tip location sensor for temporary placement on the patient's chest, and an ultrasound probe. The tip location sensor senses a magnetic field of a stylet disposed in a lumen of the catheter when the catheter is disposed in the vasculature. The ultrasound probe ultrasonically images a portion of the vasculature prior to intravascular introduction of the catheter. The ultrasound probe includes user input controls for controlling use of the ultrasound probe in an ultrasound mode and use of the tip location sensor in a tip location mode. In another embodiment, ECG signal-based catheter tip guidance is included in the integrated system to enable guidance of the catheter tip to a desired position with respect to a node of the patient's heart.

Abstract: An electrophysiology catheter, e.g., a coronary sinus catheter, for insertion into a cardiac vessel, such as the coronary sinus, includes a handle and a catheter shaft coupled at one end to the handle. The catheter shaft has a distal end and an anchor is associated with the catheter shaft and is movable between a deployed position and a collapsed position. In the deployed position, the anchor extends radially outward from an outer surface of the catheter shaft for contacting a wall and temporarily anchoring the catheter shaft within the coronary sinus. The catheter also includes an actuator for causing deployment and collapsing of the anchor upon manipulation of the actuator.

Abstract: A microlead, of an overall diameter less than 0.5 mm, includes a plurality of at least eight conductor wires individually insulated and twisted together. Each conductor wire includes an electrically conductive core microcable and an insulation layer surrounding the core microcable and having at least one exposed area to form a detection/stimulation electrode of the microlead. The microlead further includes a central support structure shaped as a surface of revolution, which may be free of conductor wires and of central lumen. The conductor wires are configured in one or more layers of twisted peripheral conductor wires carried by the central support structure and circumferentially distributed thereon.

Abstract: The invention relates to a bipolar myocardial pacemaker electrode (1) consisting of a plug (2), a supply line (3), a cathode (4), an anode (5), surgical thread (7) and a fixation member (8), whereby the electrode (1) has an internal lumen and is freely movable on the thread (7); the thread (7) can be guided through the inner lumen of the electrode including the supply line and plug thereof, and distally supports the fixation member (8) in the form of a knot; the supply line (3) is externally insulated and has a distal cathode pole (4) tangentially arranged on the surface of the heart in the heart tissue (myocardium) in the usage position, wherein the cathode pole consists of a conically tapering coil and the supply line (3) has an anode pole (5) arranged proximally underneath the heart in the usage position.

Abstract: A medical electrical lead includes a threaded conductor, a coil conductor, and a sleeve. The threaded conductor has an outer surface with a threaded section that includes threads defining grooves between the threads. The coil conductor has coils seated in the grooves of the threaded conductor. The coil conductor has a coil major diameter greater than a thread major diameter. The sleeve is positioned radially outward of the coil conductor and has an inner surface in contact with the coil conductor so as to produce a radially inward force compressing the coil conductor against the threaded section of the threaded conductor.

Abstract: Systems and methods make possible the placement of one or more electrode leads in a tissue region for providing functional and/or therapeutic stimulation to tissue. The systems and methods are adapted to provide the relief of pain.

Abstract: An electrical stimulation lead includes a cog-shaped conductor guide disposed either at the proximal end or the distal end of the lead. The cog-shaped conductor guide includes a central core and multiple protrusions extending outwards from the core. Conductor tracks are defined within the cog-shaped conductor guide between adjacent protrusions. Electrodes are provided along the distal end of the lead, terminals are provided along the proximal end of the lead, and conductors couple the electrodes to the terminals. An elongated lead body extends from the electrodes to the terminals of the lead. Each of the conductors has an end portion positioned within one of the conductor tracks of the cog-shaped conductor guide.

Abstract: An ablation catheter adapted for use with a guide wire has a 3-D shaped portion that carries ring electrodes for ablating a vessel or tubular region, including the renal artery. The 3-D shaped portion, for example, a helical portion, enables the ring electrodes to contact an inner surface of the vessel at a plurality of locations at different depths along the vessel to form a conduction block without forming a closed conduction loop which would otherwise increase the risk of stenosis of the vessel. In one embodiment, the catheter has a lumen with entry and exit ports to allow the guide wire to pass through the lumen but bypass the 3-D shaped portion. In another embodiment, the catheter has outer bands providing side tunnels through which the guide wire can pass through.

Abstract: A stimulation lead extends from a proximal end to a distal end and includes a plurality of electrodes disposed along the distal end of the lead; a plurality of terminals disposed along the proximal end of the lead; and an elongated body separating the plurality of electrodes from the plurality of terminals. The elongated body includes an outer tube of insulative material, and a cog-shaped conductor guide disposed within the outer tube. The conductor guide includes a central core and a plurality of protrusions extending outward from the central core. The plurality of protrusions and the outer tube define a plurality of pocket regions. The stimulation further includes a plurality of conductors disposed within the plurality of pocket regions, each conductor coupling at least one of the plurality of electrodes to at least one of the plurality of terminals.

Abstract: A catheter system including an accelerometer-based sensing assembly is provided. In particular the present teachings relate to an accelerometer based assembly used to determine contact between a catheter and surrounding proximate tissue, such as cardiac tissue. An embodiment of such a system may, for example, be used for visualization, mapping, ablation, or other methods of diagnosis and treatment of tissue and/or surrounding areas.

Abstract: According to some embodiments, a device operates by comparative morphological analysis of depolarization signals collected in spontaneous rhythm on separate respective channels, with two temporal components combined into a single 2D parametric VGM vectogram characteristic. Similarity quantification methods evaluate a variation over time of a descriptor parameter of a current VGM compared to a stored previous reference VGM. This variation is compared with predetermined thresholds to diagnose an occurrence of remodeling or reverse remodeling in a patient, and/or to detect a lead failure or an occurrence of ischemia. The descriptor parameter is a function of a velocity vector of the VGM, a comparison relating to a correlation coefficient between respective magnitudes of a current VGM velocity vector and of a reference VGM velocity vector, and an average angle between these respective velocity vectors.

Abstract: A microlead has a distal active portion formed by a microcable including an electrically conductive core coated with an insulation layer, with a plurality of exposed areas forming the stimulation electrodes. The microcable has a three-dimensional preshape inscribed in a cylindrical envelope volume so as to match the target vessel wall. The microcable includes a plurality of exposed areas regularly distributed over the circumference of the cylindrical envelope volume considered in axial projection, the exposed zones extending only over an angular sector of the microcable considered in cross section, said angular sector facing the outside of the envelope volume of the preshape.

Abstract: An implantable medical elongated member extends between a proximal end configured to be coupled to a medical device and a distal end. The implantable elongated member includes one or more fixation elements coupled to at least a middle portion and/or a proximal portion of the elongated member in order to substantially fix a position of the elongated member to tissue at one or more intermediate points between the proximal end and the distal end of the elongated member.

Abstract: An example stretchable device is described that includes electrical contacts and an interconnect coupling the electrical contacts. The interconnect has a meander-shaped configuration that includes at least one nested serpentine-shaped feature. The interconnect can be conductive or non-conductive. The meander-shaped configuration can be a serpentine structure, providing a serpentine-in-serpentine configuration.

Abstract: A catheter includes a shaft having at least one lumen. The lumen comprises a longitudinally-extending trough defined by a longitudinally-extending recess, within which a component is disposed, and a longitudinally extending open edge. The lumen further comprises a longitudinally-extending channel defined by a longitudinally-extending cavity and by the open edge of the trough. A planarity wire is disposed within the cavity and is configured to close the open edge of the trough to within a pre-defined tolerance that is less than the size of the component to retain the component in the recess.

Abstract: An implantable medical device (IMD) may include a housing having a proximal end and a distal end and a set of one or more electrodes connected to but spaced apart from the housing. The IMD may further include a controller disposed within the housing, wherein the controller is configured to sense cardiac electrical signals, and deliver electrical stimulation pulses via the first set of one or more electrodes. In some embodiments, a first portion of the housing is configured to be disposed at least partly within a coronary sinus of a patient's heart and a second portion of the housing is configured to be disposed at least partly within a right atrium of the patient's heart.

Abstract: A device for brain stimulation includes a lead having a longitudinal surface, a proximal end and a distal end. A plurality of electrodes are disposed along the longitudinal surface of the lead near the distal end of the lead. At least one marker is disposed on the longitudinal surface of the lead. The at least one marker is configured and arranged to identify a relative position of the plurality of electrodes.

Abstract: Apparatus and methods are described including a mechanical support element that is placed inside a first vein of a subject. At least one electrode disposed on the mechanical support element is placed inside the first vein, in a vicinity of a site upstream of a bifurcation with a second vein of the subject. A control unit enhances downstream blood flow from the first vein by driving the at least one electrode to divert blood downstream into the second vein by constricting the first vein at the upstream site, by driving the at least one electrode to apply a current to the vicinity of the site. The mechanical support element prevents the first vein from collapsing by providing mechanical support to the vein. Other embodiments are also described.

Abstract: An implantable electrical stimulation lead includes a lead body, electrodes disposed along a distal end of the lead body, terminals disposed along the proximal end of the lead body, and conductors coupling the terminals to the electrodes. The electrodes include a tip electrode having an electrode body with an outer stimulating surface. An internal lumen is defined in the electrode body and extends inwardly from an opening in a proximal end of the electrode body. Side apertures are formed between the outer stimulating surface and the internal lumen. A portion of the lead body is disposed within the internal lumen and side apertures through the opening in the proximal end of the electrode body. That portion of the lead body facilitates retention of the tip electrode on a distal tip of the lead body.

Abstract: An apparatus for measuring biopotential signals comprises a plurality of electrodes embedded or affixed to a wearable worn about the torso of a pregnant subject, enabling the non-invasive acquisition of electrocardiographic signals and the extraction of separate fetal and maternal electrocardiographic signals therefrom. The wearable is stretchable or adjustable to accommodate any maternal body habitus and can advantageously employ dry physiologic electrodes to eliminate the step of skin preparation and provide longer-term monitoring that is also both more convenient and more comfortable.

Abstract: A catheter for use in a patient's heart, especially for mapping a tubular region of the heart, has a catheter body, a deflectable intermediate section and a distal mapping assembly that has a generally circular portion adapted to sit on or in a tubular region of the heart. A control handle of the catheter allows for single-handed manipulation of various control mechanisms that can deflect the intermediate section and contract the mapping assembly by means of a deflection control assembly and a rotational control assembly. The deflection control assembly has a deflection arm and a rocker member. The rotational control assembly has an outer rotational member, an inner rotational member and a cam. A pair of puller members are responsive to the deflection control assembly to bi-directionally deflect the intermediate section. A third puller member is responsive to the rotational control assembly to contract the generally circular portion of the mapping assembly.

Abstract: A device and method for treating an aneurysm include a catheter capable of insertion into a body to be positioned adjacent the aneurysm, the catheter including a distal end and an operator end opposite the distal end. The catheter forms a circular pathway extending between the distal end and the operator end. A partitioner extends through the pathway of the catheter, the partitioner being rotatable within the catheter and including one or more lumens that provide an orifice from a first end of the partitioner to a second end of the partitioner. The device further includes a first coil extending through the partitioner from the first end to the second end in a first lumen and a second coil extending through the partitioner from the first end to the second end in a second lumen. The first and second lumens may be fully circumscribed by the partitioner and have first and second diameters, respectively.

Abstract: A sensing/pacing lead including a microcable having a diameter of at most 2 French (0.66 mm). The microcable includes an electrically conductive core cable including a plurality of strands and a composite structure formed from at least a structuring material and a radiopaque material, the radiopaque material constituting at least about 0.008 mm2 of the core cable cross section. The plurality of strands of the core cable comprises a first set of individual strands formed from the structuring material and a second set of individual strands formed from the radiopaque material, or a plurality of strands each comprising a first and second layer, one of which is the structuring material and the other the radiopaque material. The microcable further includes a polymer insulation layer at least partially surrounding the core cable and at least one electrode.

Abstract: An imaging window of an imaging catheter includes a first imaging window section and a second imaging window section. The first imaging window section has a finite length and is formed from a first material having a flexural modulus. The second imaging window section has a finite length and is formed from a second material having a flexural modulus. The flexural modulus of the first material is different than the flexural modulus of the second material.

Abstract: A method and system for the diagnosis of anomalies in a lead attached to an implantable medical device, such as an implantable cardioverter defibrillator (ICD), including an insulation breach resulting in a short circuit of the high-voltage shock pulse. Determination that the defibrillation pathway is shorted may be made by initial analysis of a Reference EGM and Diagnostic EGM and subsequent analysis of Differential Diagnostic EGMs. Upon determining if a specific defibrillation pathway is shorted, the nonessential defibrillation electrode of that pathway may be excluded from the defibrillation circuit, delivering defibrillation current only between functioning defibrillation electrodes. Alternatively, the ICD system can confirm the presence of a lead anomaly with one or more alternative diagnostic approaches. Patient and remote-monitoring alerts may be initiated.

Abstract: A lead delivery apparatus and a method of delivering a medical lead to an anatomic target site. The method includes inserting a hydraulic plug into an internal delivery lumen of a delivery shaft, and coupling a medical lead to the hydraulic plug. Hydraulic pressure is applied to the hydraulic plug through the delivery lumen, thereby moving the hydraulic plug toward an anatomic target site, and advancing the medical lead toward the target site.

Abstract: An exemplary cochlear electrode array includes a flexible body having a pre-curved spiral shape so as to conform with the curvature of a human cochlea, a plurality of stimulation electrode contacts spaced apart along a first side of the flexible body, a bundle of wires embedded within the flexible body for electrically connecting the electrode contacts to at least one stimulation signal source, at least one inflatable portion extending along at least part of the length of the flexible body, the at least one inflatable portion being adapted to straighten the flexible body, starting from the pre-curved shape, prior to insertion into the cochlea upon being inflated by being filled with gas or liquid, and to allow the flexible body to gradually reassume its pre-curved shape during insertion of the flexible body into the cochlea upon gradual withdrawal of gas or liquid from the at least one inflatable portion.

Abstract: A method for mapping a cardiac chamber includes sensing activation signals of intrinsic physiological activity with a plurality of electrodes disposed in or near the cardiac chamber, the activation signals including a near-field activation signal component and a far-field activation signal component, isolating R-wave events in the activation signals, generating a far-field activation template representative of the far-field activation signal component based on the R-wave events, and filtering the far-field activation template from the activation signals to identify the near-field activation signal components in the activation signals.