Convertible basket catheter

Abstract

The invention relates to a convertible basket catheter. The present disclosure relates to a catheter having a basket-shaped electrode assembly formed from a plurality of spines with electrodes at a distal end of a catheter body. The basket electrode assembly has structural elements at a proximal end and a distal end. The structural element may maintain the spines in a desired spatial relationship with each other and / or may couple distal ends of the spines to a traction member. The basket-shaped electrode assembly has an expanded arrangement in which the spines are arcuately curved outwardly and a collapsed arrangement in which the spines are disposed generally along the longitudinal axis of the catheter body.

Description

Technical Field

[0001] This disclosure relates to electrophysiological (EP) catheters for mapping and / or ablation in the heart, and more specifically to structural elements for securely deploying EP catheters in a patient. Background Technology

[0002] Electrophysiological catheters are commonly used to map electrical activity in the heart and / or to deliver energy for therapeutic procedures. Various electrode designs for different purposes are known. Specifically, catheters with basket electrode arrays are known and described, for example, in U.S. Patents 5,772,590, 6,748,255, and 6,973,340, the entire disclosure of each of which is incorporated herein by reference.

[0003] A basket catheter typically has an elongated catheter body and a basket-shaped electrode assembly mounted at the distal end of the catheter body. The basket assembly has a proximal end and a distal end, and includes multiple ridges connected at its proximal and distal ends. Each ridge includes at least one electrode. The basket assembly has an expanded arrangement and a collapsed arrangement, in which the ridges are radially outwardly arched, and in which the ridges are generally arranged along the axis of the catheter body. In some cases, the expanded arrangement can be achieved by withdrawing a traction member fixed to the distal end of the ridge proximally to shorten the relative longitudinal distance to the proximal end of the ridge, resulting in an outward arching.

[0004] For diagnostic purposes, it is desirable for basket-type assemblies to detect as much electrical function as possible in the region where the electrode assembly is deployed, such as the left or right atrium, with as few heartbeats as possible, including a single heartbeat. To reliably achieve this, the basket should be deployed in a specific configuration that positions the ridges with a desired relative spacing to each other, in order to obtain uniform coverage of the tissue in the region of interest between the ridge-borne electrodes and the tissue. Similarly, when using basket-type catheters to deliver energy for therapeutic procedures such as tissue ablation, achieving a specific ridge configuration when the basket assembly is deployed helps ensure that one or more ridge-borne electrodes are positioned at the intended treatment site.

[0005] Therefore, it is desirable to provide structural elements for controlling the deployment of the ridges to achieve a specific configuration as the basket assembly expands. Similarly, it is desirable to provide structural elements at the distal end of the basket assembly that allow the tensioning members to be securely fixed to the distal end of the ridge. Additionally, it is desirable to provide structural elements at the distal end to maintain the relative radial spacing of the ridges. Furthermore, it is desirable to provide structural elements at the proximal end of the basket assembly to maintain the relative radial spacing of the ridges. The technology of this disclosure, as described in the following material, satisfies these and other needs. Summary of the Invention

[0006] This disclosure relates to a catheter having an elongated catheter body having a proximal end and a distal end, and at least one lumen passing through the elongated catheter body. The catheter body has a basket-shaped electrode assembly at its distal end, the basket-shaped electrode assembly including a plurality of ridges having a proximal end connected by proximal and distal structural elements, each ridge including a plurality of electrodes, wherein the basket-shaped electrode assembly has an expanded arrangement and a collapsed arrangement, in which the ridges are radially outwardly arched, and in which the ridges are arranged generally along the longitudinal axis of the catheter body.

[0007] In one aspect, the catheter has a traction member with a proximal end and a distal end, the traction member being slidably disposed within the lumen and aligned with the longitudinal axis of the catheter body, such that when the traction member is in the distal position relative to the catheter body along the longitudinal axis, the basket electrode assembly has a collapsed arrangement, and wherein when the traction member is in the proximal position of the distal position, the basket electrode assembly has an expanded arrangement.

[0008] In one aspect, the distal structural element may be a cover configured to couple a traction member to the distal ends of a plurality of ridges. The cover may have an inwardly recessed portion defining a shoulder that engages a stop at the distal end of the traction member.

[0009] In one respect, the ridge can be an integral framework formed by cut-off tubes of material. For example, the tubes of material can be shape memory materials.

[0010] In one aspect, the cover may have a proximal portion with an outer diameter and a distal portion with an outer diameter, wherein the outer diameter of the proximal portion is smaller than the outer diameter of the distal portion. The outer diameter of the proximal portion is sized to fit snugly within the inner diameter of the tube of material.

[0011] In one respect, the opposing ridges of the basket electrode assembly can be formed by continuous ring members. For example, the ring members can be made of shape memory material.

[0012] In one aspect, the cover may have opposing holes through which the ring member passes. These opposing holes may be multiple pairs of opposing holes, wherein each pair of opposing holes is spirally staggered relative to adjacent holes. Alternatively, the cover may have opposite windows through which the ring member passes.

[0013] In one aspect, the proximal structural element may be a bushing disposed within the lumen of the catheter body. The bushing has a plurality of longitudinal channels distributed around its outer diameter, each channel configured to receive and secure the proximal end of a ridge. When the bushing is disposed within the catheter body, each channel forms a lumen having the inner diameter of the catheter body. The bushing may have a first lumen configured to receive a traction member. Alternatively or additionally, the bushing may have a second lumen configured to guide flushing fluid to a basket electrode assembly. Alternatively or additionally, the bushing may have a third lumen configured to secure a position sensor.

[0014] This disclosure also relates to a processing method that may include providing a catheter having an elongated catheter body having a proximal end, a distal end, and at least one lumen passing through the elongated catheter body, and a basket electrode assembly located at the distal end of the catheter body, the basket electrode assembly including a plurality of ridges having a proximal end connected by proximal and distal structural elements, each ridge including a plurality of electrodes; advancing the distal end of the catheter with the basket electrode assembly into a desired area in a patient using an interconnecting frame in a collapsed arrangement, in which the ridges are generally arranged along the longitudinal axis of the catheter body; and presenting the basket electrode assembly in an expanded arrangement, in which the elements are positioned radially outward from the longitudinal axis of the catheter body such that at least one electrode contacts tissue.

[0015] In one aspect, the method may include receiving an electrical signal from at least one electrode in contact with tissue.

[0016] In one aspect, the method may include delivering radiofrequency energy to at least one electrode in contact with tissue to form an ablation focus. Attached Figure Description

[0017] Other features and advantages will become apparent from the following and more specific description of preferred embodiments of the present disclosure, as shown in the accompanying drawings, and wherein similar reference characters throughout the views generally refer to the same parts or elements, and wherein:

[0018] Figure 1 This is a top plan view of a basket electrode assembly conduit according to one embodiment.

[0019] Figure 2 This is a schematic diagram of the frame of a basket-shaped electrode assembly formed by a cut-off tube according to one embodiment.

[0020] Figure 3 For the implementation of an scheme and Figure 2 A schematic cross-sectional view of the cover structure elements used together with the frame.

[0021] Figure 4This is a schematic diagram of the distal end of a tension member according to one embodiment.

[0022] Figure 5 A detailed diagram illustrating the interaction between the cover and frame of a basket electrode assembly according to one embodiment.

[0023] Figure 6 This is a schematic diagram of a continuous ring structure forming opposing ridges according to the implementation scheme.

[0024] Figure 7 This is a schematic diagram of another continuous ring member forming an opposing ridge according to the implementation scheme.

[0025] Figure 8 A detailed diagram illustrating the connection between the cover and frame of a basket-shaped electrode assembly formed by continuous ring members, according to one embodiment.

[0026] Figure 9 A schematic cross-sectional view of a cover structure element used with a frame of continuous ring members according to one embodiment.

[0027] Figure 10 A schematic cross-sectional view of another cap structure element configuration used with a frame of continuous ring members according to one embodiment.

[0028] Figure 11 This is a schematic front view of a bushing structural element according to one embodiment.

[0029] Figure 12 This is a schematic diagram of a basket-shaped electrode assembly arranged for expansion within the left atrium according to one embodiment.

[0030] Figure 13 This is a schematic diagram of an invasive medical procedure using a basket electrode assembly according to one implementation scheme. Detailed Implementation

[0031] First, it should be understood that this disclosure is not limited to specific exemplary materials, constructions, conventions, methods, or structures, as these are all subject to variation. Therefore, while preferred materials and methods are described herein, many similar or equivalent options may be used in the practice or implementation of this disclosure.

[0032] It should also be understood that the terminology used herein is for the purpose of describing specific embodiments of this disclosure only and is not intended to be limiting.

[0033] The specific embodiments illustrated below with reference to the accompanying drawings are intended to describe exemplary embodiments of this disclosure and are not intended to represent the only exemplary embodiments in which this disclosure may be practiced. The term “exemplary” as used throughout this specification means “serving as an example, instance, or illustration” and is not necessarily to be construed as preferred or superior to other exemplary embodiments. The detailed description includes specific details intended to provide a thorough understanding of the exemplary embodiments of this specification. It will be apparent to those skilled in the art that the exemplary embodiments of this specification may be practiced without these specific details. In some instances, well-known structures and apparatuses are shown in the block diagrams to avoid obscuring the novelty of the exemplary embodiments presented herein.

[0034] For the sake of brevity and clarity only, directional terms such as top, bottom, left, right, up, down, above, above, below, under, behind, rear, and front may be used relative to the accompanying drawings. These and similar directional terms should not be construed as limiting the scope of this disclosure in any way.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0036] Finally, as used in this specification and the appended claims, unless otherwise expressly stated in the text, the singular forms “a,” “an,” and “the” include the plural references.

[0037] Some types of electrical activity within the heart chambers are non-periodic. Examples include arterial fibrillation or arterial tachycardia arising from scarring in the ventricular wall caused by infarction. This type of electrical activity is random with each heartbeat. To analyze or “map” this type of electrical activity, it is desirable to obtain a ‘picture’ as quickly as possible, such as within a single heartbeat. In other words, all points of the mapping or picture can be obtained simultaneously within a tenth of a second. According to the technology of this disclosure, a basket electrode assembly can be more closely conformed to the anatomy of a patient's heart for accurate mapping of this electrical activity. By employing structural elements at the proximal and distal ends of the basket electrode assembly, the ridge can be reliably deployed into the desired specific configuration.

[0038] like Figure 1As shown, catheter 10 includes an elongated catheter body 12 with proximal and distal ends and a control handle 14 at the proximal end of the catheter body. A basket-shaped electrode assembly 16 has multiple ridges 18 mounted at the distal end of the elongated body 12, each ridge carrying multiple electrodes 20. The catheter body 12 includes an elongated tubular structure having a single axial or central lumen (not shown), but may optionally have multiple lumens if desired. To enable accurate mapping of electrical signals, such as detecting most or substantially all electrical function of the right or left atrium in a few heartbeats like a single heartbeat, some embodiments provide an electrode array with a relatively high density. Thus, the number of ridges 18 employed can be eight, ten, twelve, or any other suitable number. The ridges 18 may be radially distributed uniformly or non-uniformly. Additionally, each ridge 18 may include multiple electrodes 20, such as at least ten and up to about 16 electrodes per ridge. In other applications, fewer ridges and / or electrodes may be employed as desired. Additionally, the electrodes may be evenly distributed along each ridge or may be deflected proximally, centrally, or distally to facilitate the analysis of the measured electrical signals or to access desired areas of the patient's anatomy. In some embodiments, one or more electrodes 20 may be configured to deliver radiofrequency energy to ablate tissue adjacent to the electrodes.

[0039] The catheter body 12 is flexible, i.e., capable of bending, but substantially incompressible along its length. The catheter body 12 can have any suitable construction and can be made of any suitable material. One construction includes materials such as polyurethane or... The outer wall is made of (polyether block amide). The outer wall includes an embedded braided mesh of stainless steel or the like to increase the torsional stiffness of the catheter body 12, such that the distal end of the catheter body rotates accordingly when the control handle 14 is rotated. The outer diameter of the catheter body 12 is not definitive, but should generally be as small as possible and may not exceed about 10 French kilometres depending on the desired application. Similarly, the thickness of the outer wall is not definitive, but may be thin enough to accommodate the traction member wire, lead wire, sensor cable, and any other wires, cables, or tubes in the central lumen. If desired, the inner surface of the outer wall may be lined with a reinforcing tube (not shown) to provide improved torsional stability. U.S. Patent 6,064,905 describes and illustrates examples of catheter body construction suitable for use in conjunction with the present invention, the entire disclosure of which is incorporated herein by reference.

[0040] The basket electrode assembly 16 may also include a traction member 22, which is generally coaxial with the catheter body 12 and extends from the proximal end of the catheter body 12 through the central lumen, and is attached to a structural element such as a cap 24 to couple the traction member 22 to the distal end of the ridge 18. Longitudinal movement of the traction member 22 relative to the catheter body is provided, allowing the distal end of the ridge 18 to move proximally relative to the catheter body 12 to radially expand the electrode assembly. In some embodiments, the ridge 18 may have a pre-formed expanded configuration present when unconstrained, and the traction member is not required. The proximal end of the ridge 18 may be provided by another structural element disposed within the catheter body 12, such as... Figure 1 The bushing 26, schematically shown, receives the ridge 18. As will be described in further detail below, the bushing 26 secures and holds the proximal ends of the ridge 18 relative to each other in a desired radial configuration.

[0041] Because the proximal end of the ridge 18 is secured to the catheter body 12 by the bushing 26, the distance between the distal and proximal ends of the ridge 18 shortens when the ridge 18 is outwardly arched into an expanded arrangement, which can be associated with the relative movement of the traction member 22 in the proximal direction. Alternatively or additionally, the ridge 18 may comprise materials that facilitate an expanded arrangement, such as shape memory materials, such that the traction member 22 facilitates or eliminates the transition between the expanded and collapsed arrangements. In embodiments, the traction member 22 may comprise a wire or thiourea tube formed of a suitable shape memory material, such as a nickel-titanium alloy as described below. As will be appreciated, different amounts of relative movement of the traction member 22 along the longitudinal axis can affect the degree of arching, such as enabling the ridge 18 to exert greater pressure on the atrial tissue for better contact between the tissue and the electrodes on the ridge. Therefore, when the basket electrode assembly 16 is in an expanded arrangement, the user can modify the shape of the electrode assembly by adjusting the distance the traction member 22 is retracted.

[0042] The range of travel of the tension member 22 from its farthest position to a relatively closer position corresponds to the basket electrode assembly 16 from a collapsed arrangement to having a shape similar to... Figure 1The deflection of the generally spherical inflatable arrangement is shown. In the collapsed arrangement, the ridge can be constrained, for example, by a guide sheath, and the ridge can be deflected from the collapsed arrangement to the first inflatable deployment configuration by withdrawing the guide sheath and applying sufficient force to the traction member 22. As will be understood, in the collapsed arrangement, the ridge 18 is generally linearly aligned with the catheter body 12 to minimize the outer diameter for insertion and withdrawal from the patient. In the inflatable arrangement, the ridge 18 of the basket electrode assembly 16 is outwardly arched. Presenting the inflatable arrangement when positioned at the desired location within the patient allows the electrode 20 to contract or be closer to the wall of the chamber or other areas where the basket electrode assembly 16 is positioned. The overall size of the basket electrode assembly 16 can be selected based on the patient's anatomy to provide a close fit to areas of the patient being investigated or treated, such as the right or left atrium. In some embodiments, the traction member 22 may be coupled to an actuator on a control handle 14, which may be a sliding lever, a rotary button, or any other suitable implementation. Thus, the actuator can be used to adjust the relative longitudinal position of the traction member 22, and specifically can be configured to adjust the position of the traction member 22 to achieve one or more desired expansion arrangements of the basket electrode assembly 16.

[0043] The basket electrode assembly 16 can be constructed using a framework with a suitable substrate material. In one aspect, shape memory materials can be used to help present both expanding and collapsing arrangements. For example, nickel-titanium alloys known as nitinol can be used. At body temperature, nitinol wires are flexible and elastic, and like most metals, they deform when subjected to minimal force and return to their shape when that force is absent. Nitinol belongs to a class of materials called shape memory alloys (SMAs), which possess interesting mechanical properties beyond flexibility and elasticity, including shape memory and superelasticity. This allows nitinol to "remember its shape" according to its temperature phase. The austenitic phase is the stronger, higher-temperature phase of nitinol with a simple cubic crystal structure. Superelastic behavior occurs in this phase (a temperature distribution exceeding 50°C-60°C). Correspondingly, the martensitic phase is the relatively weaker, lower-temperature phase with a twinned crystal structure. When nitinol materials are in the martensitic phase, they are relatively easy to deform and will retain that deformation. However, when heated above its austenitic transformation temperature, nitinol will revert to its pre-deformed shape, resulting in a "shape memory" effect. The temperature at which nitinol begins to transform into austenite upon heating is referred to as the "As" temperature. The temperature at which nitinol has completed its austenitic transformation upon heating is referred to as the "Af" temperature. Therefore, the basket electrode assembly 16, when formed from such a material, can have a three-dimensional shape that readily collapses to be fed into the guide sheath and then readily returns to its expanded shape memory configuration upon removal of the guide sheath and / or actuation traction member 22 upon delivery to the desired area of ​​the patient.

[0044] In one exemplary embodiment, frame 28 can be formed from a nickel-titanium nanotube by laser cutting or other similar techniques to provide, for example, Figure 2 The overall frame is shown. According to this embodiment, a 3mm tube with a wall thickness of approximately 8 to 9 mils can be used. Alternative embodiments may employ other materials that do not necessarily have shape memory properties but are sufficiently flexible to accommodate both expansion and collapse arrangements. These materials include metallic materials such as stainless steel, or polymeric materials such as polyetheretherketone (PEEK).

[0045] An embodiment of the cover 24 suitable for use with a frame 28 formed of a cut-off tube is described in Figure 3 As shown in the cross-sectional view. The cap 24 may include a proximal portion 30 having a diameter D1, the diameter being sized to fit snugly within the inner diameter of the tube used to construct the frame 28, with the distal portion of the cap 24 remaining intact. Additionally, the cap 24 may include a distal portion 32 having a diameter D2 greater than D1, the diameter D2 being, for example, approximately the outer diameter of the tube used to construct the frame 28 but at least greater than the inner diameter of the tube. Therefore, the proximal portion 30 of the cap 24 may be disposed within and fixed to the distal end of the frame 28, within the intact, uncut portion. The cap 24 also includes an inner recess 34 having an inner diameter D3. A lumen 36 extends from the recess 34 to the proximal end of the cap 24. The lumen 36 has an inner diameter D4 that mates with the inner diameter D3 of the recess 34 to define a shoulder 38 that intersects with the tension member 22. Figure 4 As shown, the distal end of the pulling member 22 may have a stop 40, which has a diameter D3 that fits within the recess 34 but is larger than the inner diameter D4 of the lumen 36, such that the stop 40 engages the outer diameter D5 of the shoulder 38. Therefore, the pulling member 22 can be easily secured to the cover 24, and the stop 40 provides mechanical action with the shoulder 38, such that proximal movement of the pulling member 22 reliably affects the corresponding proximal movement of the cover 24 and the distal end of the ridge 18, causing it to arch outward as the basket electrode assembly 16 expands. The stop 40 can be held within the recess 34 by suitable techniques, including adhesive bonding.

[0046] A detailed view of the distal end of the basket electrode assembly 16 is shown in Figure 5 As shown in the figure, Figure 5 The connection between the cap 24 and the tubular distal end of the frame 28 is shown. As shown in this view, the ridge 18 has a base formed by the frame 28 and may include a non-conductive cover 42, which may include a biocompatible plastic tubing, such as polyurethane or polyimide tubing, on which the electrode 20 is mounted. In embodiments characterized by a polymer frame, the non-conductive cover may be omitted. Figure 5The configuration shown employs the distal portion of a ridge 18 exhibiting a concave configuration, generally positioned within a radius of curvature defined by adjacent lateral portions. For safety reasons, this recessed design keeps the top of the basket electrode assembly 16 approximately flush with the outer curvature by presenting a relatively blunt and non-invasive surface. Additionally, the electrode 20 may be positioned at an inflection point where the distal concave portion 32 transforms into a proximal convex portion to provide coverage in the polarity region of the basket electrode assembly 16. The ridge 18 may be configured with varying degrees of curvature to more closely conform to the patient's anatomy.

[0047] In another exemplary embodiment, the frame of the basket electrode assembly 16 may employ a continuous ring of material to form two opposing ridges 18. For example, Figure 6 and Figure 7 Ring members 44 and 46 are shown respectively, each ring member forming an opposing ridge 18. (See also...) Figure 6 As shown, the ring member 44 may have a distal region 48 of a protrusion generally formed outside the radius of curvature of the ring member 44. Alternatively, as in Figure 7 As shown, ring member 46 may have a distal region 50 of a concave surface generally formed inside the radius of curvature of ring member 46. Raised regions 48 and / or concave regions 50 may be employed to reduce interference with other ring members, which may be stacked to form a complete basket electrode assembly 16 with a desired number of ridges 18. The radius of curvature for the raised regions 48 and / or concave regions 50 for each ring member may be adjusted as needed to provide clearance relative to other ring members. Ring members 44 and / or 46 may comprise any suitable resilient material, such as those discussed above relative to frame 28. In some embodiments, nitinol or other shape memory materials may be used. Additionally, ring members 44 and / or 46 may have circular, elliptical, square, or other rectangular shapes as desired.

[0048] A partial view of an embodiment of the basket electrode assembly 16 formed by the ring member 44 is shown in Figure 8 As shown in the diagram. Similar to other embodiments described above, the ring member 44 may have a non-conductive cover 42 on which the electrodes 20 are disposed. A structural element for attaching the distal end of the ridge 18 to the traction member 22 is provided in the form of a cover 52 having a plurality of opposing holes 54 through which the ring member 44 is guided. In other embodiments, each ridge 18 may be formed of a single member, each member being secured at its distal end via the holes 54 of the cover 52. In each of these embodiments, the holes 54 help maintain a desired radial spacing between the distal ends of the ridges 18 relative to each other.

[0049] Detailed sectional view of cover 52 is in Figure 9As shown in the figure. Each pair of opposing holes 54, such as holes 54a and 54b, may be spirally staggered around the radius of the cover 52 to provide interference between the ring members 44 (not shown in this view) guided through it. The shape of the holes 54 may be set to accommodate the profiles of the ring members 44 and / or 46, such as by having a circular, elliptical, square, or rectangular configuration. The cover 52 may also be characterized by a recess 56 and a lumen 58, which mate to form a shoulder 60. The dimensions of these aspects of the cover 52 may be set relative to the cover 24 as described above to secure the stop 40 of the pulling member 22. Alternative embodiments are as follows. Figure 10 The diagram is shown in the form of a cover 62, which incorporates multiple windows 64 to provide greater clearance for the ring members 44 and / or 46. Although not shown in this view, the cover 62 may also have an inner shoulder similar to other embodiments of the stop 40 used to engage the tension member 22.

[0050] As described above, whether cut off from a tube such as in frame 28 or from the proximal end of the ridge 18 including the opposing ends of ring members 44 and / or 46, it can be received and secured by structural elements such as bushing 26, which in Figure 11 As shown in the diagram. The bushing 26 may have a generally cylindrical shape, its dimensions set to fit snugly within the catheter body 12. A plurality of longitudinal channels 66 are radially distributed around the cylindrical body of the bushing 26. Each channel 66 may be sized to receive and secure the proximal end of a ridge 18. When the bushing 26 is disposed within the catheter body, the channels 66 may form lumens by combining with the surfaces of the inner diameter of the catheter body 12, and the ridges 18 may be secured by the channels in any suitable manner by adhesive bonding. As will be understood, the channels 66 maintain a desired radial spacing between the proximal ends of the ridges 18 relative to each other. Although shown as uniformly distributed, in some embodiments, the channels may be non-uniformly distributed to produce a corresponding radial distribution of the ridges 18, if desired. The bushing 26 may have a first lumen 68 through which a traction member 44 can pass, extending from the proximal end to the distal end. The bushing 26 may have a second lumen 70, also extending from the proximal end to the distal end, for supplying a suitable flushing fluid, such as heparinized saline, to the basket electrode assembly 16. Accessories (not shown) may be provided in the control handle 14 to direct flushing fluid from a suitable source or pump into the lumen or into tubing extending through the catheter body 12 communicating with the lumen 70. The bushing 26 may have a third lumen 72 terminating within the body of the bushing 26 to secure and position a position sensor (not shown in this figure) that may be used to help determine the location of the basket electrode assembly 16 within the patient's body, as described in further detail below.

[0051] In one aspect, electrophysiologists may introduce a guiding sheath, guidewire, and dilator into the patient, as is commonly known in the art. An example of a suitable guiding sheath for use with the catheter of this invention is PREFACE.TM Braided guide sheaths (commercially available from Biosense Webster, Inc. (Diamond Bar, CA)) and DiRex TM Guide sheath (commercially available from BARD (Murray Hill, NJ)). Insert the guidewire, remove the dilator, and guide the catheter through the guide sheath, thereby pulling the guidewire lumen in the traction member to allow the catheter to pass through the guidewire. In such cases... Figure 12 In the exemplary procedure described, a catheter is first introduced into the right atrium (RA) via the inferior vena cava (IVC), through which the catheter passes through the diaphragm (S) to reach the left atrium (LA).

[0052] As will be known, in the collapsed position, the guide sheath 74 covers the ridge 18 of the basket electrode assembly 16, allowing the entire catheter to pass through the patient's vascular system to the desired location. The traction member 22 can be positioned distal to the catheter body to allow the ridge of the assembly to flatten as the assembly passes through the guide sheath. Once the distal end of the catheter reaches the desired location, such as the left atrium, the guide sheath is withdrawn to expose the basket electrode assembly 16. The traction member 22 is pulled proximally or otherwise manipulated, causing the ridge 18 to fold outward between the distal and proximal junctions. As the basket electrode assembly 16 expands radially, the electrode 20 contacts the atrial tissue.

[0053] When the basket electrode assembly 16 is deployed in its expanded arrangement, an electrophysiologist can map local activation time and / or perform ablation using electrode 20, which can guide the electrophysiologist in diagnosing or treating a patient. The catheter may include one or more reference ring electrodes mounted on the catheter body, and / or one or more reference electrodes may be placed externally to the patient. By using the catheter of the present invention with multiple electrodes on the basket electrode assembly, an electrophysiologist can obtain the true anatomy of the cavernous sinus region of the heart (including the atria), allowing for faster mapping of the measurement area by measuring fewer points than with conventional catheters.

[0054] In another aspect, each ridge 18 may include wiring with built-in or embedded leads for electrodes 20 carried by the ridge, as described in U.S. Application Serial No. 13 / 860,921 entitled “HIGH DENSITY ELECTRODE STRUCTURE”, filed April 11, 2013, and U.S. Application Serial No. 14 / 063,477 entitled “CONNECTION OF ELECTRODES TOWIRES COILED ON A CORE”, filed October 25, 2013, the entire disclosure of which is incorporated herein by reference.

[0055] To help illustrate the use of the basket electrode assembly 16, Figure 13This is a schematic diagram of an invasive medical procedure according to an embodiment. A catheter 10, having a basket electrode assembly 16 (not shown in this view) at its distal end, may have a connector 80 at its proximal end for coupling wires from its respective electrodes 20 (not shown in this view) to a console 82 for recording and analyzing the signals they detect. An electrophysiologist 84 may insert the catheter 10 into a patient 86 to acquire electrode potential signals from the patient's heart 88. A professional uses a control handle 14 attached to the catheter to perform the insertion. The console 82 may include a processing unit 90 that analyzes the received signals and can present the results of the analysis on a display 92 attached to the console. The results are typically in the form of a mapping, digital display, and / or graph derived from the signals.

[0056] In another aspect, the processing unit 90 may also receive signals from one or more position sensors positioned near the distal end of the catheter 10 adjacent to the basket electrode assembly 16, such as by securing it in the lumen 72 using the bushing 26 as described above. Each of the one or more sensors may include a magnetic field-responsive coil or multiple such coils. Using multiple coils allows six-dimensional position and orientation coordinates to be determined. In response to a magnetic field from an outer coil, the sensor can thus generate an electrical position signal, enabling the processor 90 to determine the position (e.g., location and orientation) of the distal end of the catheter 10 within the cardiac cavity. An electrophysiologist can then observe the position of the basket electrode assembly 16 on an image of the patient's heart on a display 92. This position sensing method can be illustrated by using CARTO. TM The system is used to implement this, the CARTO TM The system is manufactured by Biosense Webster Inc. (Diamond Bar, Calif.) and is described in detail in U.S. Patent Nos. 5,391,199, 6,690,963, 6,484,118, 6,239,724, 6,618,612, and 6,332,089, PCT Patent Publication WO 96 / 05768, and U.S. Patent Application Publications 2002 / 0065455 A1, 2003 / 0120150 A1, and 2004 / 0068178 A1, the disclosures of which are incorporated herein by reference in their entirety. Other position sensing techniques may also be employed, as will be appreciated. If desired, at least two position sensors may be positioned proximal and distal relative to the electrode array assembly 16. The coordinates of the distal sensor relative to the proximal sensor can be determined, and other known information relating to the configuration of the basket electrode assembly 16 is used to locate the position of each electrode 2 in the electrodes 20.

[0057] The present invention has been described above with respect to the currently disclosed embodiments. Those skilled in the art will recognize that changes and modifications can be made to the described structures without intentionally departing from the principles, spirit, and scope of the invention. As will be understood by those skilled in the art, the drawings are not necessarily drawn to scale. Therefore, the above description should not be construed as relating only to the precise structures described and illustrated in the drawings, but should be considered to be consistent with and supported by the following claims, which have the fullest and most reasonable scope.

Claims

1. A catheter comprising an elongated catheter body having a proximal end, a distal end, and at least one lumen passing through the elongated catheter body, and a basket electrode assembly located at the distal end of the catheter body, the basket electrode assembly comprising a plurality of ridges having a proximal end connected by a proximal structural element and a distal structural element, each ridge comprising a plurality of electrodes, wherein the basket electrode assembly has an expanded arrangement and a collapsed arrangement, wherein in the expanded arrangement the ridges are radially outwardly arched, and in the collapsed arrangement the ridges are generally arranged along the longitudinal axis of the catheter body.

2. The catheter of claim 1 further comprises a traction member having a proximal end and a distal end, the traction member being slidably disposed within the lumen and aligned with the longitudinal axis of the catheter body such that the basket electrode assembly has the collapsed arrangement when the traction member is at its distal position relative to the catheter body along the longitudinal axis, and wherein the basket electrode assembly has the expanded arrangement when the traction member is proximal to the distal position.

3. The catheter of claim 2, wherein the distal structural element includes a cap configured to couple the traction member to the distal end of the plurality of ridges.

4. The catheter of claim 3, wherein the cap has an inwardly recessed portion defining a shoulder that engages a stop located at the distal end of the traction member.

5. The catheter of claim 4, wherein the ridge comprises an integral frame formed by a truncated tube of material.

6. The conduit of claim 5, wherein the material comprises a shape memory material.

7. The catheter of claim 5, wherein the cap has a proximal portion having an outer diameter and a distal portion having an outer diameter, wherein the outer diameter of the proximal portion is smaller than the outer diameter of the distal portion.

8. The conduit of claim 7, wherein the outer diameter of the proximal portion is configured to fit snugly within the inner diameter of the tube made of the material.

9. The catheter according to claim 4, wherein the opposing ridges are formed by continuous annular members.

10. The conduit of claim 9, wherein the annular component comprises a shape memory material.

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