WO2019046888A1

WO2019046888A1 - Electrophysiology catheter with sensor

Info

Publication number: WO2019046888A1
Application number: PCT/AU2018/050864
Authority: WO
Inventors: David Ogle; Binu Parameswaran
Original assignee: Cathrx Ltd
Priority date: 2017-09-05
Filing date: 2018-08-15
Publication date: 2019-03-14

Abstract

A shape imparting means for a catheter sheath comprising an elongate member with a distal end and a proximal end. The elongate member comprising a lumen extending from the proximal end to the distal end. The elongate member comprising a mounting means near to the proximal the distal end for receiving a sensor, and wherein when the shape imparting means is inserted in a catheter sheath, the sensor is rotatable about an axial direction, relative to said catheter sheath.

Description

ELECTROPHYSIOLOGY CATHETER WITH SENSOR TECHNICAL FIELD

[0001] The present invention relates to an electrophysiological catheter. More particularly, the present disclosure is related to an electrophysiological catheter with a sensor mounted on the deflection means.

BACKGROUND

[0002] Diagnostic and mapping catheters are commonly used for in vivo procedures to sense for abnormalities within a patient. Typically, these procedures are conducted via a keyhole surgery and with a device which will cause minimal potential damage to a patient. A catheter is a typical device for such a procedure.

[0003] Catheters for diagnostic procedures are well known within the art, however there are a number of problems associated with known diagnostic and sensing catheters.

[0004] US Patent No. 5,938,603 (Ponzi), there is disclosed a steerable electromagnetic catheter comprises a catheter body, tip section, and control handle. The catheter body has proximal and distal ends and at least one lumen extending therethrough. The control handle is fixedly attached to the proximal end of the catheter body. The tip section comprises tubing having proximal and distal ends and at least one lumen extending therethrough. The proximal end of the tip section is fixedly attached to the distal end of the catheter body. A tip electrode is mounted at the distal end of the tip section and has at least one blind hole extending from its proximal end. The blind hole is in communication with at least one lumen in the tip section. An electromagnetic sensor is mounted in the tip section. The catheter further comprises a means for deflecting the tip section.

However, this document does not teach or suggest the advantages of the present disclosure, and is in generally relatively large and may be difficult to navigate.

[0005] EP Patent No. 0879069 (Ponzi, et. al.) relates to an electrophysiology catheter (an electrode catheter) having an electromagnetic sensor designed internally into the top portion. The catheter is a size 7 French or 8 French of metal braided construction with preferably three lumens. The catheter has a deflectable tip utilizing an offset lumen with a puller wire, a non-compressible coil in the body section, and a compressible TEFLON sheath in the tip section. The electromagnetic sensor is mounted internally in the catheter tip by a combination of a hole drilled in the three lumen tip, and a hollow bridging that covers the electromagnetic sensor and connects the tip electrode to the catheter shaft. The tip electrode is secured to the end of the bridging tube by an etched TEFLON ring which mates the electrode stem to the inside of the ring. This disclosure does not teach or suggest the advantages of the present disclosure.

[0006] Known catheter leads comprising electrodes are generally formed with

biocompatible metal components which are adapted to be inserted into a patient. These leads generally have sensors which are used to detect electromagnetic signals within a patient. However, positioning these sensing devices may be difficult. Some known catheters are formed with a pull-wire which is fixed to the distal end of the catheter sheath, however this prevents the pull- wire from being separated from the catheter sheath. This will prevent the catheter sheath and the pull-wire from being reusable. Further, using a pull-wire may only impart limited shapes to the catheter sheath, and must be imparted to the location in which the pull- wire is fixed to the catheter sheath. Further, catheters equipped with pull-wires generally are not capable of having a stylet to replace the pull- wire, nor is the function of a pull- wire an equivalent to that of a stylet. More particularly, the pull- wire is similar to a tendon, in which applying tension to a pull-wire causes the catheter lead attached thereto to deform. However, these types of deflection means can only impart a shape at the location in which the pull-wire is attached and activated, which can cause steering problems in use.

[0007] Most catheters known are also incapable of being used more than once, and this is generally a large expense for procedures. Further accidental contact with a non- sterile surface may cause an entire catheter to be discarded without use which can cause substantial expense to a hospital or clinician. In addition, discarding catheters may also result in expensive rare earth metals to be discarded along with a catheter lead, or the electronics of the catheter handle to be discarded despite no contact with biological matter. Further, replacing components of a catheter lead and/or catheter handle is generally unknown in the art.

[0008] It may also be difficult to form a desired shape at a desired portion of the catheter. This can cause the lead to snag anatomy in use, which can cause severe lesions, internal bleeding and undesired medical complications.

[0009] None of the above referenced prior art documents anticipate a deflection means with a sensor attached thereto, nor do they anticipate the advantages of such a

configuration. There may be a need to develop a catheter which provides an advantage over the prior art which may allow for reduced manufacturing costs in relation to known catheters and may also provide for a catheter with a superior cross section. There may also be a need to develop a catheter which can be more readily manipulated in use, as desired by a clinician.

[0010] Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.

[0011] Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.

SUMMARY

[0012] PROBLEMS TO BE SOLVED

[0013] It may be advantageous to provide a thinner sensing catheter for sensing diagnostic applications.

[0014] It may be advantageous to provide a more compact catheter for sensing diagnostic applications. [0015] It may be advantageous to provide for a catheter with a sensor which is more easily manoeuvrable and/or positionable.

[0016] It may be advantageous to provide for a catheter with a sensor which is displaceable relative to a catheter sheath.

[0017] It may be advantageous to provide a catheter with a sensor which is rotatable.

[0018] It may be advantageous to provide for a catheter with a sensor which is translatable.

[0019] It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

[0020] MEANS FOR SOLVING THE PROBLEM

[0021] A first aspect of the present disclosure may relate to a shape imparting means for a catheter sheath. The shape imparting means comprising an elongate member with a distal end and a proximal end. The elongate member comprising a lumen extending from the proximal end to the distal end. The elongate member comprising a mounting means positionable proximal the distal end for receiving a sensor; and wherein when the shape imparting means is inserted in a catheter sheath, the sensor can be rotated about an axial direction, relative to said catheter sheath. Further, the sensor may be adapted to be translatable, relative to said catheter sheath.

[0022] Preferably, the shape imparting means is a stylet. Preferably, the mounting means releasably retains the sensor. Preferably, the shape imparting means further comprises a pull-wire. Preferably, the pull-wire comprises a further sensor. Preferably, the sensor is axially displaceable relative to a distal end of the catheter sheath. Preferably, the sensor is a sensor assembly. Preferably, at least one further sensor is disposed on the elongate element. Preferably, an extension element is disposed on the distal end of the shape imparting means. Preferably, the mounting means is disposed on the extension element and the extension element is axially displaceable to the shape imparting means.

[0023] In yet another aspect, the present invention may relate to stylet for a multifunction catheter. The stylet comprising an elongate stylet body having a proximal end and a distal end an extension element adapted to be disposed over the distal end of the stylet. The extension element comprising at least one sensor mounted thereon, and wherein when the extension element and stylet are disposed in a lumen of a catheter sheath the sensor is rotatable and/or translatable about an axial direction, relative to said catheter sheath.

[0024] Preferably, the at least one sensor includes a sensor assembly. Preferably, the stylet further comprises a pull-wire. Preferably, at least one further sensor is disposed on the pull- wire. Preferably, a distal end of the pull- wire extends distally of the distal end of the stylet.

[0025] In the context of the present invention, the words "comprise", "comprising" and the like are to be construed in their inclusive, as opposed to their exclusive, sense, that is in the sense of "including, but not limited to".

[0026] The invention is to be interpreted with reference to the at least one of the technical problems described or affiliated with the background art. The present aims to solve or ameliorate at least one of the technical problems and this may result in one or more advantageous effects as defined by this specification and described in detail with reference to the preferred embodiments of the present invention.

BRIEF DESCRIPTION OF THE FIGURES

[0027] Figure 1 illustrates a perspective view of an embodiment of a catheter with a sheath and a handle of the present disclosure;

[0028] Figure 2 illustrates a partial transparent cut away view of an embodiment of a catheter with a sensor mounted on a deflection means; [0029] Figure 3 illustrates a transparent schematic view of an embodiment of a sensor mounted on a deflection means inside a catheter sheath;

[0030] Figure 4 illustrates a partial schematic transparent view an embodiment of a deflection means with an end cap;

[0031] Figure 5 illustrates a schematic of another embodiment of a stylet with a plurality of sensor pairs disposed on said stylet;

[0032] Figure 6 illustrates a schematic of another embodiment of a stylet with a plurality of sensors disposed proximally of the distal end of the stylet;

[0033] Figure 7 illustrates a schematic of an embodiment of a stacked multiple sensors on and inside of a mounting means at distal end of a stylet;

[0034] Figure 8 illustrates a schematic of an embodiment of a sensor assembly disposed on the distal end of a stylet;

[0035] Figure 9 illustrates a perspective view of an embodiment of a stylet with a plurality of sensors on and inside a holder at distal end of a stylet;

[0036] Figure 10 illustrates a schematic of an embodiment of a plurality of sensors on a distal end of a pull- wire;

[0037] Figure 11 illustrates a schematic of yet another embodiment of a sensor arrangement with a plurality of sensors on an extension of a pull-wire; and

[0038] Figure 12 illustrates a schematic perspective view of an embodiment of a stacked sensor mounted on a distal end of a stylet. DESCRIPTION OF THE INVENTION

[0039] Preferred embodiments of the invention will now be described with reference to the accompanying drawings and non-limiting examples.

[0040] Referring to the embodiment of Figure 1, there is illustrated a catheter 10. The catheter is preferably an electrophysiological catheter 10. The catheter 10 comprises a catheter handle 11 and a catheter sheath 12. The catheter sheath 12 is an elongate element extending from a distal end 16 of the handle 11. The catheter sheath 12 is preferably formed with a generally tubular member having a proximal end 20

connectable with the handle 11 and a distal end 22 having one or more electrodes 38 attached to the catheter sheath 12. The catheter sheath 12 may also be referred to herein as tubular member 12. The catheter sheath 12 preferably comprises a lumen 24 extending form the proximal end 20 to the distal end 22 of the catheter sheath 12.

[0041] The catheter sheath 12 may be formed from a polymeric material or other predetermined non-conductive biocompatible material. The catheter sheath 12 also include conductive fibres and/or conductive wires (not shown). The conductive wires may be embedded, fixed, glued, adhered, or attached to the wall of the catheter sheath 12. Optionally, the conductive wires may be disposed, embedded or formed in the wall of the catheter sheath 12. The conductive wires may be at least one of; helically wound, laid in rows, intertwined, woven or braided. The conductive wires may also be pressed between two or more layers of non-conductive material, or a layer of conductive material and a second layer of non-conductive material. The conductive wires may alternatively be attached to the wall of the catheter sheath 12 such that the conductive wires are in electrical communication with the electrodes 38 of the catheter sheath 12. Optionally, a second set of conductive wires may be overlaid on a first set of conductive wires. The second set of wires may be disposed in a generally opposing direction relative to the first set of wires. It will be appreciated that any number of layers of conductive wires may be formed with, or within, the wall of the catheter sheath 12. [0042] The electrodes 38 may be fixed to the catheter sheath 12 by any conventional method, such as induction heating, heat treatment, heat-shrink fastening methods, crimping, swaging, or any other desired method. At least one of the conductive wires may be attached to at least one electrode 38 such that the electrode 38 may be energised. The electrodes may be a ring type electrode 38. The ring electrodes 38 may be of a fixed size which do not expand or contract during use or when being secured to the catheter sheath 12. Preferably, the outer surface of an electrode 38 is substantially flush with the outer surface of the catheter sheath 12.

[0043] A shape imparting element 26 may be received in the lumen 24 of the catheter sheath 12. Turning to Figure 2, the shape imparting element 26 is preferably a stylet 26 which may be used to impart a desired shape to at least a portion of the catheter sheath 12. Shape imparting element 26 will be referred to herein as "stylet 26", but it will be appreciated that the term "shape imparting element" may include any means to impart a shape. The shape imparted to the catheter sheath 12 may be at any desired location of the catheter sheath 12. The stylet 26 is axially displaceable relative to the catheter sheath 12, such that the shape imparted to the catheter sheath 12 may also be axially displaced relative to the distal end 22 of the catheter sheath 12. This may be advantageous as the axial displacement of the shape (imparted by stylet 26) may allow the distal end 22 of the catheter sheath 12 to be projected distal the stylet 26, which may assist a user to navigate the catheter sheath 12 through tortuous anatomy to a desired location.

[0044] The stylet 26 may be formed from a shape memory alloy or a shape memory material such that a predefined shape is imparted to the stylet at rest. The stylet 26 may also include a stylet lumen 27 which houses a further shape imparting means, such as a further stylet (not shown) and/or a pull-wire 32 which can be used to impart a shape to the stylet 26, which in turn imparts a shape to the catheter sheath 12. The stylet lumen 27 may further house other components, such as at least one electrical conductor which may be connected to a sensor 50. The sensor 50 is preferably a diagnostic sensor, or an electromagnetic sensor which may be adapted to detect electrical signals of a patient. The sensor 50 may be any desired sensor for mapping or diagnostic use. The sensor 50 may be fixed or attached to the electrical conductor, or sensor conductor 52 of the stylet 26.

[0045] Preferably, the distal end of the stylet 26 comprises a sensor attachment means or sensor mounting means 60. Illustrated in Figures 2 and 3, there is shown a cup 60 mounting means which allows for the sensor 50 to be mounted on the stylet 26. In this way the sensor 50 can be moved axially in the catheter sheath 12 such that the sensor 50 can be moved relative to the distal end or the end cap of the catheter sheath 12. In this way the catheter sheath 12 may be positioned in a desired manner and the sensor 50 may be moved axially within the lumen of the catheter sheath 12. This may allow for a "drag sensing" operation to be performed, in which the sensor 50 is moved incrementally or continuously in the catheter sheath 12 to map or sense a desired area. This is of further advantage if the catheter also comprises at least one electrode 38 on the catheter sheath 12, as this will allow sensing to be performed followed by ablation. In this way both drag sensing and drag ablation (drag burning) can be performed by the single device at relatively the same time or performed in discrete sensing actions. A discrete sensing action may be any action includes which activating a sensor 50 and subsequently deactivating a sensor. It will be appreciated that deactivating a sensor 50 need not be the same sensor activated, and may be any active sensor 50 switched to an inactive state.

[0046] Further, having a sensor 50 attached to a stylet 26 may also allow for the sensor 50 to be rotated internal the catheter sheath 12. This is a significant advantage as this allows for more accurate placement of a sensor 50 without imparting torsion to the catheter sheath 12 which could cause internal damage to a patient, or cause misplacement during movement. The stylet 26 is preferably rotatable about the axial direction to allow for at least one of the shape of the stylet 26 to be rotated or the sensor 50 to be rotated. This may be of particular advantage with respect to ultrasonic directional sensors, or sensors 50 which are required to be in a predetermined orientation to sense. Optionally, the sensor 50 may be an EMF sensor. The sensors 50 may be any predetermined sensor type, or combination of different sensor types. [0047] The catheter sheath 12 may have a plurality of lumens extending from the proximal end 20 of the sheath to the distal end 22. The stylet 26 may be housed within a predetermined lumen of the catheter sheath 12 and the other lumens may be used for fluid, electrical leads or further sensors. The proximal ends 28, 20 of the stylet 26 and the catheter sheath 12 are connected to the handle at the handle distal end 16. The distal end of the stylet 30 may be substantially in register with the distal end 22 of the catheter sheath 12, or the end cap 40. It is preferred that the stylet be positionable within the catheter sheath 12 at any location such that the stylet can be used to impart a desired shape to the catheter sheath 12.

[0048] A plurality of sensors may be disposed on the stylet 26 and activated at any desired time, either individually or in an array (see Figures 5 to 12, for example), Activating the sensors 50, 51 in a desired manner may allow for different electromagnetic radiation or magnetic fields to be sensed more effectively compared to the state of the art.

[0049] In yet another embodiment, the sensor mounting means 60 may be replaced by a further sheath, or a sensor sheath (also referred to herein as extension element 76), mounted on the stylet, and a catheter sheath 12 mounted on the sensor sheath. In this arrangement, the sensor sheath is an intermediary layer between the stylet 26 and the catheter sheath 12. This may facilitate for the catheter sheath 12 to be projected distally of the sensor sheath, and the sensor sheath to be projected distally of the stylet 26, which may allow for improved navigation. Optionally, more than one shape imparting means may be disposed in the catheter sheath 12 and operable independently of each other.

[0050] A sensor sheath (extension element 76) may comprise any number of sensors 50, at any desired spacing. The spacing of the sensors 50 may provide for different sensing arrangements for different applications. Preferably, the sensors are spaced at known intervals, and are preferably arranged to allow for sensing in multiple directions radially of the catheter sheath 12.

[0051] The sensor may be displaceable relative to the distal portion of the catheter sheath 12. The distal portion 22 of the catheter sheath 12 includes the distal end 22 and at least a portion proximal the distal end 22. Drag sensing may allow for a catheter sheath 12 to remain in a desired location while the sensors 50, 51 internal to the catheter sheath 12 are moved within the lumen 24 of the sheath 12. Moving the sensors 50 within the lumen may be a relatively axial movement. Having the sensor 50 adapted to move may allow for a predetermined path to be mapped or sensed by the catheter. This is a significant advantage over known sensing catheters. Further, this may be of particular advantage for a multi-function catheter, in which the catheter 10 is adapted for both sensing or mapping and also adapted to issue energy to a patient via electrodes 38. Issuing energy to a patient may be used for ablation treatments or other energy delivery treatment. Further, allowing a sensor 50 to be displaced relatively from electrodes 38 on a catheter sheath 12 may allow for improved sensing with relatively less interference from the electrodes 38.

[0052] The cup 60 portion may releasably retain a sensor 50 by factional forces, adhesive, a locking mechanism, pressure, a vacuum, or any other suitable attachment means to releasably secure a sensor to the stylet. In yet another embodiment, the sensor 50 may be fixedly attached to the stylet 26 or integrally formed with the stylet 26 such that the sensor 50 is not removable without damaging the stylet 26. A physical attachment means may include at least one of a cap, a clasp, or a claw, however a physical attachment means may be any suitable element to secure or fix the sensor 50 in a desired location relative to the stylet 26.

[0053] In at least one embodiment, the sensor 50 is adapted to be substantially in register with the distal end of the catheter sheath 12. More preferably, the stylet 26 is receivable in the end cap 40. Optionally, the end cap 40 may be adapted to function as an electrode and/or a fluid delivery means. If the end cap 40 is adapted to allow for fluid delivery, the end cap comprises at least one aperture (not shown) to allow for fluids to be delivered to a target location, when in use. An array of apertures may be disposed in the end cap 40 to allow for delivery of fluid. Electrodes 38 may be formed with apertures to allow for delivery of fluid, or the catheter sheath 12 may comprise fluid apertures or a window to allow for expulsion of fluids. [0054] In yet another embodiment, the sensor 50 in the lumen 24 of the sheath 12 may be disposed intermediate two electrodes 38 disposed on the catheter sheath 12 or may be disposed between the distal end 22 and the electrode 38 most distal the proximal end of the catheter sheath 12.

[0055] The stylet 26 preferably comprises a pull-wire 32 such that manipulation of the pull wire 32 allows for a deflection of the stylet 26. The pull-wire 32 may be disposed in a lumen 27 of the stylet 26. The stylet 26 may be formed form a shape memory alloy, such as Nitinol (NiTi). The pull-wire 32 may also be formed from a shape memory alloy. Preferably any metal components are also a biocompatible material. The distal end 32 of the pull- wire 32 may be fixed to the distal end 30 of the stylet 26 and the proximal end 34 of the pull-wire 32 may be fixed to a manipulation means in the handle 11 of the catheter 10. The stylet 26 is also preferably connected to the catheter handle 11 and may also be in communication with a manipulation means. The manipulation means may be a control knob or an actuator. The control knob or actuator may be effected a rotational force or a torque to impart a shape to at least one of the stylet or impart a tension to the pull- wire 32. The actuator may be a button or slider or any other means which may impart a movement to the pull-wire 32 and/or the stylet 26. The actuator may also effect movement of the extension element 76.

[0056] Preferably, the stylet 26 comprises a sensor mounting means 60 to allow for mounting the sensor 50 at a predetermined location on the stylet 26. The sensor mounting means 60 is preferably located at the distal end 30 of the stylet 26 such that the sensor 50 can be moved into register with the distal end of the catheter sheath 12. The mounting means 60 may be a cup type arrangement in which the sensor 50 is positioned within the cup.

[0057] The cup 60 may also be adapted to seat the sensor 50. The cup 60 having at least one wall 62 and a base portion 64. At least one of the wall 62 and the base may comprise an aperture (not shown) to allow for an electrical connection to be established between the sensor 50 and the catheter handle 11. Preferably, a sensor lead 52 is provided for said electrical connection. [0058] The sensor 50 is preferably in communication with at least one component of the handle 11, such as a power source or a temiinal. The stylet 26 may be fixed to the catheter handle 11, or may be removably attached to the handle 11. The catheter sheath 12 may also be removably attached to the handle 11 or fixedly attached. Preferably, the catheter sheath 12 is removably with respect to the stylet 26 such that at least the stylet 26 can be replaced, reprocessed and/or reused. In this way the internal components of the catheter 10 can be reused and therefore reduce the potential costs for a procedure.

Further, removing the catheter sheath 12 to allow for access to the stylet 26 may allow for replacement, recovery or removal of the sensor 50.

[0059] An intermediate sheath (not shown) may be disposed between the stylet 26 and the catheter sheath 12. The intermediate sheath may be provided with at least one of sensors 50, electrodes 38, and conductive elements. The conductive elements may be conductive wires, similar to that of sensor lead 52, or fibres which may be energised to provide energy to the sensor 50 and/or the electrodes 38. If there is an intermediate layer, the external layer may comprise at least one aperture to allow for a fluid to be passed through at least one aperture or window in said catheter sheath 12. The fluid may be used to improve the sensing capabilities of the catheter 10 in use. Preferably, the fluid provided is a saline fluid or a fluid which allows for enhancement of sensing, or provision of energy from electrodes which may be of particular use for ablation electrodes.

[0060] The catheter sheath 12 comprises at least one lumen extending from the proximal end 20 to the distal end 22. However, the catheter sheath 12 may be provided with any number of lumens. The lumens may be any desired shape, such as circle, oval, kidney shape, or any other predetermined desired shape. Preferably, the lumens in the catheter sheath 12 are adapted to house at least one of electrical leads, stylets 26, pull-wires 32 or sensors.

[0061] Referring to Figure 3, the end cap 40 of the sheath 12 preferably comprises protrusion 42 with a lumen 44. The protrusion 42 of the end cap 40 is preferably received in the distal end 22 of the catheter sheath 12, and more preferably the protrusion 42 is received in the lumen 24 of the catheter sheath 12. The lumen 44 of the protrusion 42 is preferably adapted to receive at least a portion of the sensor 50, such that at least a portion of the sensor may be received in the lumen 44 of the protrusion 42. The end cap 40 further comprises an external portion which projects beyond the distal end of the catheter sheath 12. The end cap 40 may optionally be of a relatively larger diameter to that of the catheter sheath 12; however, it will be appreciated that the end cap 40 may be the same, or smaller, French (Fr) or diameter as that of the catheter sheath 12. The end cap 40 may have a spherical or bulbous profile.

[0062] Optionally, if the catheter sheath 12 comprises multiple lumens (not shown), the end cap 40 may also comprise an equal number of protrusions 42, or fewer, than the number of lumens of the catheter sheath 12.

[0063] The catheter sheath 12 may be formed with a varying rigidity and/or flexibility. Having a catheter sheath 12 of varying rigidity and/or flexibility may allow for more efficient and/or easier placement of the catheter sheath 12 in vivo.

[0064] In another embodiment, the present invention relates to a reposable

electrophysiology catheter 10 with an electromagnetic mapping sensor designed internally at the distal end. The unique modular design of the reposable catheter consists of a deflectable catheter sheath 12, a control handle 11 attached to the proximal end of the catheter sheath 12 and stylet housed within the lumen 24 of the catheter sheath 12. The catheter sheath 12 extends from the control handle and houses the stylet 26, or other desired shape imparting means 26, which is also connected to the control handle. An electromagnetic sensor is mounted internally on the distal end of the stylet 26.

[0065] In yet another embodiment, the invention may relate to the novel design of a sensor, preferably an electromagnetic sensor, mounted internally on the distal end of a stylet 26 of reposable electrophysiology catheter 10. The sensor 50 may be adapted for use for 3D mapping and tip visualisation when the catheter 10 is connected to a mapping system. The reposable catheter 10 may be of any desired diameter for example, 4.5 French, 6 French, or 7.5 French. The catheter sheath 12 may be formed with varying French which may assist with placement and/or operation of the catheter 10. [0066] The unique design of the stylet 26 may be formed from a deflectable hollow tube made from a highly deflectable material such as Nitinol (NiTi). A pull- wire 32 is inserted inside the lumen 27 of the stylet 26 and extends along its length. The respective distal end of the stylet 26 and pull-wire 32 may be crimped together and their proximal ends are fastened to the handle 11 or in the handle 11. The proximal end 28 of the stylet can be fixed while the proximal end 34 of the pull-wire 32 can be fastened to a gear mechanism or other manipulation means. When the control handle, which is connected to the gear mechanism or manipulation means, is steered, the pull-wire 32 pulls on the crimped distal end of the stylet 26. The relative movement between the pull-wire 32 and the stylet defines the deflection and manoeuvrability of the catheter 10.

[0067] The stylet 26 further includes a 'cup' 60 designed inside the hollow of the tube, which is beyond the distal crimped joint. The cup 60, on the non-magnetic stylet 26, holds and firmly mounts the aforementioned electromagnetic sensor therein. An sensor cable 52 is connected to the sensor 50 and runs along the length of the stylet 26. The distal end of the sensor cable 52 is connected to the sensor 50 and the proximal end of the sensor cable 52 is connected to a temiinal (not shown) inside the handle 11. A data cable connects to the handle, preferably the proximal end 14 of the handle, for transferring sensed data (sensed signals converted to data) from the catheter to the 3D mapping system. Optionally, the stylet 26 may be withdrawn entirely from the catheter 10 and a further shape imparting means or other desired structure may be inserted into the catheter sheath 12. It will be appreciated that the stylet 26 may be removed from the handle 11 during in vivo procedures.

[0068] In yet another embodiment, the sensor 50 on stylet 26 may be moved

incrementally internal the sheath. In this way a drag sensing application may be effected, or an incremental sensing application may be effected. This may provide for a more consistent mapping and/or sensing operation to be carried out. The control handle may allow for incremental displacement of the stylet 26 and/or sensor 50, or for a

predetermined displacement velocity relative to the catheter sheath 12 distal end. [0069] Figure 4 illustrates an embodiment of a capped stylet with a pull-wire 32 in a lumen 27 of the stylet 26. The cap 51 of the stylet 26 is shown as being fitted over the end portion of the distal end of the stylet 26 and does not require a cup or sensor mount, as the cap 51 is adapted to mount the stylet without a mounting element. In this way the cap 51 is relatively large than the stylet 26. The stylet 26 is receivable within a lumen 24 of a catheter sheath 12, such that manipulation of the stylet 26 imparts a shape to the catheter sheath 12. The cap 51 may also be adapted to function as a sensor 50. The cap 51 may have hemispherical profile, a bulbous profile or a rounded profile which will reduce the potential for the cap to puncture a catheter sheath 12. However, it will be appreciated that the cap may be any desired shape or profile. Preferably, if the cap 51 is a sensor 50, the sensor 50 is connected by a sensor lead 52 to the handle 11 to control the sensor 50 to send and/or receive data. The sensor lead 52 may be disposed within the wall of the stylet 26, or within the lumen 27 of the stylet 26, or adjacent the external wall of the stylet 26. In another embodiment, the pull- wire may be used to house or act as the sensor lead 52.

[0070] Referring to Figure 5, there is shown a further embodiment of a stylet 26 with an end cap 51 mounted at the distal end of a stylet 26 and a plurality of sensor pairs 54 on the stylet 26. The profile of the sensor pairs 54 preferably conform to the axial cross- sectional shape of the stylet 26 to allow for a slimmer cross sectional area of the stylet 26. The sensor pairs 54 may be stacked or disposed in any other predeteimined configuration. Each of the sensor pairs 54 may be connected to the handle 11 by at least one sensor lead 52, or each sensor 50/sensor pair 54 may be connected by respective sensor leads 52. Any number of sensor leads 52 and connections may be used with the sensors and the handle 11.

[0071] The sensors 50 may be spaced by at any desired interval, and may be disposed in a predetermined array. While the sensor pairs 54 are illustrated as substantially aligned, a sensor pair 54 may be radially offset relative to an adjacent sensor pair 54. Optionally, the sensors 50 may be adapted to flex or deform when in use such that manoeuvrability of the catheter 10 is maintained. [0072] Similar to Figure 5, Figure 6 illustrates a further embodiment of a stylet 26 with a plurality of sensors 50 mounted on the shaft of the stylet 26. The sensors may be ring sensors 50 which are mounted or fixed to the stylet 26. The sensors 50 may be attached, fixed or mounted to the stylet 26 by crimping, swaging, heat treatment, gluing, adhering, welding, induction or by any other desired attachment means. While not shown, the distal portion of the catheter sheath 12 may also comprise an end sensor. The ring electrodes 38 (of the sheath 12) or ring sensors 50 may be spaced at any predetermined interval, and preferably are mounted at evenly spaced intervals.

[0073] Figure 7 illustrates a further embodiment of a stylet 26 with sensors 50. The sensors are disposed on an external surface of an extension element 76 and on an inner surface of the extension element 76. The extension element 76 has at least one lumen, and the extension element 76 preferably mounts onto the distal end of the stylet 26. The extension element 76 may be displaceable relative to the stylet 26. The sensors 50 may be disposed on, or in, the extension element 76 in any desired manner. While Figure 7 illustrates the sensors 50 being internal the extension element 76 at the distal end and a number of sensors 50 disposed external the extension element 76 proximal the distal end of the stylet 26, the sensors 50 may be disposed in any configuration, either internal and/or external the extension element 76. Optionally, the stylet 26 may also include sensors mounted on the exterior, such as that seen in Figure 5 or Figure 6. The extension element 76 may extend to, or near to, the proximal end of the stylet 26 such that the shaft of the stylet 26 is surrounded or enclosed by the extension element 76.

[0074] In an alternate embodiment, the extension member 76 is fixed, and is not axially displaceable relative to the stylet 26. In this way the relative distance between the distal end of the extension element 76 and the stylet 26 will be known.

[0075] A sensor assembly 70 is illustrated as being mounted to a stylet in Figure 8. The sensor assembly 70 can be mounted to the stylet 26 or in a lumen 27 of the stylet 26. The assembly 70 preferably comprises a plurality of sensors 50 which may be disposed in a predetermined array or arrangement. The mounting portion 60 of the stylet 26 may comprise an elongate element 74 extending distally relative to the distal end of the stylet 26. The sensors 50 can be disposed on the elongate element 74. The elongate element 74 may comprise a plurality of sensors 50, or a sensor assembly 70, or a distal mounting means 60.

[0076] Optionally, the stylet 26 may be tapered or stepped at the distal end, such that a mounting means may be placed on the stylet 26. In this way the mounting means external wall is flush, or substantially aligned, with the external wall of the stylet 26 proximal the step such that there is a single diameter (French). Optionally, the stylet may have a varying diameter, or French, which may be advantageous for navigating anatomy of a patient.

[0077] Figure 9 illustrates a combination of a sensor assembly 70 and an extension element 76. The sensor assembly of Figure 9 is disposed on the distal end of the extension element 76, and the extension element 76 is disposed on the stylet 26. The extension element 76 can be fitted with at least one sensor 50 disposed on the extension element 76, and at least one further sensor 50 disposed internal the extension element 76. The internal sensors (internal the lumen of the extension element 76) and the external sensors (external the lumen of the extension element 76), may be spaced evenly or in any pattern or predetermined array. It will be appreciated that sensors 50 may be bundled together in groups and activated individually, activated in groups, or all sensors 50 activated all at once. In this way different sensing or mapping operations may be performed.

[0078] Yet another embodiment is illustrated in Figure 10, in which a plurality of sensors are disposed on a pull-wire 32 of the stylet 26. The stylet may be used to impart a desired shape proximally of the pull-wire 32 and the pull-wire 32 may be used to impart a discrete shape distally of the stylet 26. In this embodiment, the pull-wire 32 may be connected or fixed to the catheter sheath 12. Preferably, at least the distal portion 36 of the pull-wire is formed with a relatively higher rigidity to that of the proximal portion 34 of the pull-wire 32. The higher rigidity of the pull-wire may allow for the plurality of sensors 50 disposed thereon to be carried more effectively, and retain a desired shape when in use. [0079] A further embodiment of a stylet with a plurality of sensors is shown in Figure 11. The stylet 26 is shown with a plurality of sensors 50 disposed on the stylet 26, and a plurality of sensors 50 disposed on the pull-wire 32 and a further plurality of sensors disposed on an extension element 76. It is noted that this Figure only shows a portion of the stylet 26 and extension element 76.

[0080] A further embodiment of a stylet 26 is illustrated in Figure 12. The stylet 26 comprises a stylet extension 80 a multiple sensors 50. The sensors 50 are mounted at least in part internal to the stylet extension 80 and a portion of the sensors may be disposed external to the extension 80. Further ring sensors 50 may be disposed on the external surface 82 of the stylet extension 80. The stylet extension 80 may allow for a further sensor 50 or other element to be mounted at the distal end of the stylet extension 80. The pull-wire 32 may be fixed to the stylet 26 or the stylet extension 80. The termination (location of fixing) of the pull-wire 32 will dictate where the stylet and/or the stylet extension 80 will deflect or deform.

[0081] The extension element 76 may be formed from any desired material, and is preferably a biocompatible polymer. The stylet extension 80 may also be formed from any desired material which is biocompatible, however it is preferred that the material is the same as, or similar in material properties to that of the stylet 26. Optionally, the stylet extension 80 may be have a different flexibility or rigidity relative to the stylet 26 which may assist with navigation. The rigidity of the catheter sheath 12 may be increased by the inclusion of the extension element 76, or impart a predetermined shape to the catheter sheath 12.

[0082] The catheter 10 of the present disclosure may reduce the potential for cross contamination and functional degradation typically associated with multiple-use devices. Namely, the catheter sheath 12 can be disposed of after use, and the handle and stylet may be sterilised using autoclave processes or other conventional sterilisation processes. In this way the catheter can be reused while also removing the inherent risks associated with The handle 10 and the stylet assembly (preferably includes at least two of the following components; 26, 32, 50, 60) are reposable and/or reprocessable. After use, the catheter sheath 12 can be removed and discarded and the handle 11 and stylet assembly can be sterilised using a sterilisation tray. The sterilised handle 11 and stylet assembly can then assembled with a new, sterile catheter sheath 12 for use in a subsequent procedure.

[0083] In yet another embodiment, the shape imparting means for a catheter sheath comprises an elongate member with a distal end 30 and a proximal end 28. The elongate member comprising a lumen 27 extending from the proximal end 28 to the distal end 30. The elongate member comprising a mounting means 60 positionable proximal the distal end 30 for receiving a sensor 50; and wherein when the shape imparting means can be inserted in a catheter sheath 12, the sensor 50 can be rotated about an axial direction, relative to said catheter sheath 12. The sensor 50 may also be translatable relative to said catheter sheath 12. Optionally, the sensors 50 may be axially displaceable relative to each other.

[0084] The extension element 76 may be relatively displaceable to the stylet 26, and therefore sensors 50 on the extension element 26 may be at least one of translatable, displaceable and/or rotatable relative to the sensors 50 on the stylet 26. Similarly, if the stylet comprises a stylet extension 80, the stylet extension 80 (and any sensors 50 thereon) may be at least one of translatable, displaceable and/or rotatable relative to the sensors 50 on the stylet 26. It will be appreciated that sensors 50 may instead be sensor pairs 54, and/or sensor assemblies 70 if desired.

[0085] Optionally, the shape imparting means 26 is a stylet 26. Optionally, the mounting means releasably retains the sensor 50. Optionally, the shape imparting means 26 further comprises a pull-wire 32. Optionally, the pull-wire 32 comprises a further sensor 50. Optionally, the sensor 50 is axially displaceable relative to a distal end 22 of the catheter sheath 12. Optionally, the sensor is a sensor assembly. Optionally, at least one further sensor 50 is disposed on the elongate element. Optionally, an extension element 76 is disposed on the distal end of the shape imparting means 26. Optionally, the mounting means is disposed on the extension element and the extension element 76 is axially displaceable to the shape imparting means 26. [0086] In yet another embodiment, a stylet may comprise an elongate stylet body having a proximal end 28 and a distal end 30 an extension element 80 adapted to be disposed over the distal end 30 of the stylet 26. The extension element 80 comprising at least one sensor 50 mounted thereon, and wherein when the extension element 80 and stylet 26 are disposed in a lumen 24 of a catheter sheath 12 the sensor is rotatable about an axial direction, relative to said catheter sheath 12.

[0087] Optionally, the at least one sensor 50 includes a sensor assembly 70. Preferably, the stylet further comprises a pull-wire 32. Optionally, at least one further sensor 50 is disposed on the pull-wire 32. Optionally, a distal end of the pull-wire extends distally of the distal end of the stylet.

[0088] Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms, in keeping with the broad principles and the spirit of the invention described herein.

[0089] The present invention and the described preferred embodiments specifically include at least one feature that is industrial applicable.

Claims

1. A shape imparting means for a catheter sheath, the shape imparting means comprising;

an elongate member with a distal end and a proximal end;

the elongate member comprising a lumen extending from the proximal end to the distal end;

the elongate member comprising a mounting means near to the proximal the distal end for receiving a sensor; and

wherein when the shape imparting means is inserted in a catheter sheath, the sensor is rotatable about an axial direction, relative to said catheter sheath.

2. The shape imparting means as claimed in claim 1, wherein the shape imparting means is a stylet.

3. The shape imparting means as claimed in claim 1 or claim 2, the mounting means releasably retains the sensor.

4. The shape imparting means as claimed in any one of the preceding claims, wherein the shape imparting means further comprises a pull-wire.

5. The shape imparting means as claimed in claim 4, wherein the pull- wire comprises a further sensor.

6. The shape imparting means as claimed in any one of the preceding claims, wherein the sensor is axially displaceable relative to a distal end of the catheter sheath.

7. The shape imparting means as claimed in any one of the preceding claims, wherein the sensor is a sensor assembly.

8. The shape imparting means as claimed in any one of the preceding claims, wherein at least one further sensor is disposed on the elongate element.

9. The shape imparting means as claimed in any one of the preceding claims, wherein an extension element is disposed on the distal end of the shape imparting means.

10. The shape imparting means as claimed in claim 9, wherein the mounting means is disposed on the extension element and the extension element is axially displaceable to the shape imparting means.

11. A stylet for a multi-function catheter, the stylet comprising;

an elongate stylet body having a proximal end and a distal end;

an extension element adapted to be disposed over the distal end of the stylet; the extension element comprising at least one sensor mounted thereon, and wherein when the extension element and stylet are disposed in a lumen of a catheter sheath the sensor is rotatable about an axial direction, relative to said catheter sheath.

12. The stylet as claimed in claim 11, wherein the at least one sensor includes a sensor assembly.

13. The stylet as claimed in claim 11 or claim 12, wherein the stylet further comprises a pull- wire.

14. The stylet as claimed in claim 13, wherein at least one further sensor is disposed on the pull- wire.

15. The stylet as claimed in claim 13 or claim 14, wherein a distal end of the pull- wire extends distally of the distal end of the stylet.