Multi-layer high-density electrode mapping catheter

Abstract

Various embodiments of the invention may include a flexible catheter tip. A flexible catheter tip may include an inboard substructure defining a tip longitudinal axis, wherein the inboard substructure is formed from a first continuous element including a first rectangular cross-section. An intermediate medial cladding layer may be disposed about a first continuous element forming a distal portion of the medial substructure. An outboard substructure may extend along the head longitudinal axis, wherein the outboard substructure is formed from a second continuous element comprising a second rectangular cross-section. An intermediate outer cladding layer may be disposed about a second continuous element forming a distal portion of the outer substructure.

Description

[0001] This application is a divisional application of the invention patent application filed on July 6, 2018, entitled "Multilayer High-Density Electrode Mapping Conduit", with national application number 201880043130.X.

[0002] Cross-reference to related applications

[0003] This application claims priority to U.S. Application No. 62 / 529,586 (Application No. 568), filed July 7, 2017, entitled “Multilayer High-Density Electrode Mapping Catheter.” Application No. 568 is incorporated herein by reference as if fully set forth herein. Technical Field

[0004] This invention relates to a multilayer high-density electrode mapping catheter. Background Technology

[0005] Catheters have been used in cardiac medical procedures for many years. For example, they can be used to diagnose and treat arrhythmias when located in specific locations within the body that are inaccessible without invasive surgery.

[0006] Traditional mapping catheters may include, for example, multiple adjacent loop electrodes arranged around the longitudinal axis of the catheter and made of platinum or some other metal. These loop electrodes are relatively rigid. Similarly, traditional ablation catheters may include relatively rigid tip electrodes for delivering treatment (e.g., delivering radiofrequency (RF) ablation energy) and may also include multiple adjacent loop electrodes. When using these traditional catheters and their relatively rigid (or deformable), metallic electrodes, especially in the presence of sharp gradients and undulations, maintaining good electrical contact with cardiac tissue can be difficult.

[0007] Whether mapping or creating damage in the heart, the problem is complicated by unstable or irregular heartbeats, making it difficult to maintain adequate contact between the electrode and tissue for a sufficient duration. These problems are exacerbated on curved or tortuous surfaces. Without adequate contact between the electrode and tissue, high-quality damage or accurate mapping is impossible.

[0008] The above discussion is intended to illustrate the existing field and should not be regarded as a denial of the scope of the claims. Summary of the Invention

[0009] Various embodiments of the present invention may include a flexible catheter tip. The flexible catheter tip may include an inner lower structure defining a longitudinal axis of the tip, wherein the inner lower structure is formed by a first continuous element including a first rectangular cross-section. An intermediate inner overlay may be arranged around the first continuous element forming a distal portion of the inner lower structure. An outer lower structure may extend along the longitudinal axis of the tip, wherein the outer lower structure may be formed by a second continuous element including a second rectangular cross-section. An intermediate outer overlay may be arranged around the second continuous element forming a distal portion of the outer lower structure.

[0010] Various embodiments of the present invention may include a flexible catheter tip. The flexible catheter tip may include a flexible lower structure defining a longitudinal axis of the tip, wherein the flexible lower structure is formed by a first continuous element including a first rectangular cross-section. The flexible catheter tip may include an intermediate covering layer disposed around the first continuous element. The flexible catheter tip may include a covering layer disposed on the intermediate covering layer such that the intermediate covering layer is disposed between the covering layer and the flexible lower structure.

[0011] Various embodiments of the present invention may include a flexible catheter tip. The flexible catheter tip may include an inner lower structure defining a longitudinal axis of the tip, wherein the inner lower structure is formed by a first continuous element including a first rectangular cross-section, the first continuous element defining a first inner arm lower structure and a second inner arm lower structure, and an expanding head connected to the distal ends of each of the first inner arm lower structure and the second inner arm lower structure. The flexible catheter tip may include an intermediate inner covering layer disposed around the expanding head. The flexible catheter tip may include an outer lower structure extending along the longitudinal axis of the tip, wherein the outer lower structure is formed by a second continuous element including a second rectangular cross-section, the second continuous element defining a first outer arm lower structure and a second outer arm lower structure, and an expanding head connected to the distal ends of each of the first outer arm lower structure and the second outer arm lower structure. The flexible catheter tip may include an intermediate outer covering layer disposed around the second continuous element forming the head. Attached Figure Description

[0012] Figure 1A A top view of a high-density electrode mapping catheter according to various embodiments of the present invention is shown.

[0013] Figure 1B According to various embodiments of the present invention Figure 1A Isometric side and top views of the medium- and high-density electrode mapping catheter.

[0014] Figure 2A According to various embodiments of the present invention Figure 1AIsometric side and top views of the inner lower structure of the medium- and high-density electrode mapping catheter.

[0015] Figure 2B According to various embodiments of the present invention Figure 2A A top view of the inner lower structure shown.

[0016] Figure 3 According to various embodiments of the present invention Figure 1A A top view of the lower outer structure of the high-density electrode mapping catheter.

[0017] Figure 4 It is a middle inner covering layer according to various embodiments of the present invention. Figure 2A and 2B A top view of the inner lower structure shown.

[0018] Figure 5 It is a middle outer covering layer according to various embodiments of the present invention. Figure 3 A top view of the lower outer structure shown.

[0019] Figure 6A This is a cross-sectional view of the lower structure and the covering layer arranged around the continuous elements of the inner lower structure according to various embodiments of the present invention.

[0020] Figure 6B This is a cross-sectional view of the lower structure and the intermediate inner covering layer arranged around the first continuous element of the inner lower structure according to various embodiments of the present invention, as well as the covering layer arranged around the lower structure and the intermediate inner covering layer.

[0021] Figure 7A This is a cross-sectional view of the lower structure and the intermediate covering layer having a first outer diameter arranged around the first continuous element of the lower structure according to various embodiments of the present invention, and the covering layer arranged around the lower structure and the intermediate covering layer.

[0022] Figure 7B This is a cross-sectional view of the lower structure and the intermediate covering layer with a second outer diameter arranged around the first continuous element of the lower structure according to various embodiments of the present invention, and the covering layer arranged around the lower structure and the intermediate covering layer.

[0023] Figure 7C This is a cross-sectional view of the lower structure and the intermediate covering layer with a third outer diameter arranged around the first continuous element of the lower structure according to various embodiments of the present invention, and the covering layer arranged around the lower structure and the intermediate covering layer.

[0024] Figure 7D It is a lower structure according to various embodiments of the present invention and a first inner intermediate covering layer arranged around a first continuous element of the lower structure and having such Figure 7A The second outer intermediate coating layer of the first outer diameter is shown. Detailed Implementation

[0025] The contents of international application PCT / US2014 / 011940 entitled “Flexible High-Density Mapping Catheter Tips and Flexible Ablation Catheter Tips with Onboard High-Density Mapping Electrodes” and U.S. application 15 / 331,369 entitled “High Density Electrode Mapping Catheter” are incorporated herein by reference.

[0026] According to various embodiments of the present invention, Figure 1A This is a top view of the high-density electrode mapping catheter 101. Figure 1B Isometric side and top views of a high-density electrode mapping catheter 101 are shown. In some embodiments, the high-density electrode mapping catheter 101 may include a flexible tip 110 forming a flexible array of microelectrodes 102-1, 102-2, 102-3, and 102-4. Hereafter, microelectrodes 102-1, 102-2, 102-3, and 102-4 are referred to as microelectrodes 102. For ease of reference, in Figure 1A Only four microelectrodes 102 are shown in the figure; however, as illustrated, the high-density mapping catheter 101 may include more than four microelectrodes. This array of planar microelectrodes 102 (or “paddle-like structure”) includes four side-by-side longitudinally extending arms 103, 104, 105, and 106, forming a flexible frame on which the microelectrodes 102 are arranged. These four microelectrode-bearing arms include a first outer arm 103, a second outer arm 106, a first inner arm 104, and a second inner arm 105, which can be connected via a distal connector 109. These arms can be laterally separated from each other.

[0027] Each of the four arms can support multiple microelectrodes 102. For example, each of the four arms can support multiple microelectrodes 102 spaced apart along the length of each of the four arms. Although Figure 1A and Figure 1B The high-density electrode mapping catheters 101 shown all have four arms, but the high-density electrode mapping catheters 101 may include more or fewer arms. Furthermore, although... Figure 1A and 1BThe high-density electrode mapping conduit 101 shown includes 18 electrodes (e.g., 5 electrodes on the first outer arm 103, 5 microelectrodes on the second outer arm 106, and 4 microelectrodes on the first inner arm 104 and 4 microelectrodes on the second inner arm 105), but the conduit may include more or fewer than 18 microelectrodes. Additionally, the first outer arm 103 and the second outer arm 106 may include more or fewer than 5 microelectrodes, and the first inner arm 104 and the second inner arm 105 may include more or fewer than 4 microelectrodes.

[0028] In some embodiments, the microelectrode 102 can be used in diagnostic, therapeutic, and / or mapping procedures. For example, and not limited to, the microelectrode 102 can be used in electrophysiological studies, pacing, cardiac mapping, and / or ablation. In some embodiments, the microelectrode 102 can be used to perform unipolar or bipolar ablation. Such unipolar or bipolar ablation can create specific lesion lines or lesion patterns. In some embodiments, the microelectrode 102 can receive electrical signals from the heart, which can be used for electrophysiological studies. In some embodiments, the microelectrode 102 can perform location or positioning sensing functions related to cardiac mapping.

[0029] In some embodiments, the high-density electrode mapping catheter 101 may include a catheter shaft 107. The catheter shaft 107 may include a proximal end and a distal end. The distal end may include a connector 108 that can attach the distal end of the catheter shaft 107 to the proximal end of the planar array. Figure 1A As shown, the catheter shaft 107 may define a longitudinal axis aa, and the first lateral arm 103, the first medial arm 104, the second medial arm 105, and the second lateral arm 106 may generally extend parallel to the longitudinal axis aa. The catheter shaft 107 may be made of a flexible material, allowing it to pass through a patient's tortuous vascular system. In some embodiments, the catheter shaft 107 may include one or more annular electrodes 111 arranged along the length of the catheter shaft 107. In examples, the annular electrodes 111 may be used for diagnostic, therapeutic, and / or mapping procedures.

[0030] like Figure 1B As shown, the flexible tip 110 can be adapted to conform to tissue (e.g., cardiac tissue). For example, when the flexible tip 110 contacts tissue, it deflects to allow the flexible frame to conform to the tissue. In some embodiments, the arm (or the lower structure of the arm) includes a portion located at... Figure 1A and 1BThe distal paddle structure (or multi-arm, flexible frame carrying electrodes) of the catheter shown may be laser-cut from flexible or spring-like materials such as nitinol and / or flexible substrates as discussed herein. In some embodiments, the arm (or lower structure of the arm) may be formed from a sheet of metal (e.g., nitinol) with a uniform thickness. Different portions of the arm (or lower structure of the arm) may be formed from the sheet (e.g., cut) such that different portions of the arm have different widths. The structure of the arm (including, for example, the length and / or diameter of the arm) and the material can be adjusted or customized to produce, for example, desired elasticity, flexibility, foldability, conformability, and stiffness characteristics, including one or more characteristics that can vary from the proximal end to the distal end of a single arm or among or between multiple arms including a single paddle structure. The foldability of materials such as nitinol and / or other types of flexible substrates provides an additional advantage in facilitating the insertion of the paddle structure into the delivery catheter or cannula, whether during catheter delivery into the body or removal from the body at the end of the procedure.

[0031] In some embodiments, the arm may have a rectangular cross-section and may have well-defined edges. The arm may be encapsulated in a damage-resistant coating, which may be a thin-walled polymer (e.g., urethane) extrusion. The damage-resistant coating prevents the edges of the arm from contacting tissue, thereby preventing tissue damage. In some embodiments, the arm, and especially its edges, may contact the damage-resistant coating due to contact with tissue and / or unfolding from the sheath. Contact between the edges of the arm and the damage-resistant coating can cause wear on the coating and may ultimately result in voids within it. As further discussed herein, embodiments of the invention provide solutions to this potential event. Furthermore, embodiments of the invention prevent stretching / shrinkage of the damage-resistant coating, which can reduce the amount of wear on the coating.

[0032] The disclosed catheters with multiple microelectrodes can be used for: (1) defining regional conduction mapping of a specific-sized region (e.g., a region of one square centimeter) within the atrial wall of the heart; (2) identifying complex fragmented atrial electrographs for ablation; (3) identifying local lesion potentials between microelectrodes to obtain higher electrograph resolution; and / or (4) more precisely aligning the ablation area. Despite the potential for irregular cardiac motion, these mapping and ablation catheters are constructed to conform to and maintain contact with cardiac tissue. During cardiac motion, the enhanced stability of the catheters on the cardiac wall provides more accurate mapping and ablation due to the continuous tissue-electrode contact. Additionally, the catheters described herein can be used for endocardial and epicardial applications. For example, the planar array embodiment shown herein can be used in endocardial procedures in which the planar array of microelectrodes is positioned between the myocardial surface and the pericardium. Alternatively, this planar array embodiment can be used in epicardial procedures to rapidly scan and / or analyze the inner surface of the myocardium and quickly generate high-density maps of the electrical properties of cardiac tissue.

[0033] Figure 2A According to various embodiments of the present invention Figure 1A Isometric side and top views of the inner lower structure 120 (also referred to herein as the inner lower structure) of the high-density electrode mapping catheter are shown. In some embodiments, the inner lower structure 120 may be formed of a flexible or spring-like material such as nitinol alloy and / or a flexible substrate as described herein. In an example, the inner lower structure may be cut from a planar sheet material. The inner lower structure 120 may include a first inner arm lower structure 121 and a second inner arm lower structure 122. Although not shown, the outer lower structure (also referred to herein as the outer lower structure) providing the lower structure for the first outer arm 103 and the second outer arm 106 may be formed and / or processed in a manner similar to that discussed with reference to the inner lower structure 120. Additionally, if the high-density electrode mapping catheter includes additional arms, those arms may be formed and / or processed in a manner similar to that described with reference to the inner lower structure 120. For simplicity, the inner lower structure 120 will be discussed directly. As shown in the figure, the inner lower structure 120 may include a first proximal inner mounting arm 123 and a second proximal inner mounting arm 124. The proximal inner mounting arm is insertable into the distal end of the catheter 107 and passes through the connector 108, and can be used to connect the flexible tip 110 to the distal end of the catheter 107. In some embodiments, the proximal inner mounting arm may be inserted through a torsion liner as discussed herein.

[0034] In some embodiments, the inner lower structure 120 may define a head-end longitudinal axis, shown by line bb. In some embodiments, the inner lower structure 120 may be formed of a continuous element including a first rectangular cross-section. As used herein, the rectangular cross-section may include a square cross-section. For example, the inner lower structure 120 may include a first proximal inner mounting arm 123 and a second proximal inner mounting arm 124, which may extend along the longitudinal axis. The inner lower structure 120 may include a first inner arm lower structure 121 and a second inner arm lower structure 122, the first inner arm lower structure 121 extending distally from the first proximal inner mounting arm 123 and the second inner arm lower structure 122 extending distally from the second proximal inner mounting arm 124. In some embodiments, the first inner arm lower structure 121 and the second inner arm lower structure 122 may be parallel to the head-end longitudinal axis bb and extend parallel to each other.

[0035] In some embodiments, a first transition lower structure 126 may be disposed between a first proximal inner mounting arm 123 and a first inner arm lower structure 121. The first transition lower structure 126 may expand laterally away from the head-end longitudinal axis bb. Furthermore, a second transition lower structure 127 may be disposed between a second proximal inner mounting arm 124 and a second inner arm lower structure 122. A second transition lower structure 128 may expand laterally away from the head-end longitudinal axis bb. In this example, the first transition lower structure 126 and the second transition lower structure 128 may expand away from each other.

[0036] In some embodiments, the inner lower structure 120 includes an expanding head 130 connected to the distal ends of the first and second inner arm lower structures 121, 122. In some embodiments, the expanding head 130 may be formed by a first expanding element 132 and a second expanding element 134. As the first expanding element 132 and the second expanding element 134 extend distally, the elements 132, 134 may expand laterally away from the head-end longitudinal axis bb and away from each other before extending toward the head-end longitudinal axis bb. The first expanding element 132 and the second expanding element 134 may be connected along the head-end longitudinal axis bb. In the example, the inner lower structure may be symmetrical about both sides of the head-end longitudinal axis bb.

[0037] In some embodiments, the proximal portion of the lower inner frame structure 120 may include a first proximal inner mounting arm 123 and a second proximal inner mounting arm 124. In an example, the proximal portion of the lower inner frame structure 120 may include an inner frame locking portion 136.

[0038] Figure 2B Various embodiments according to the present invention are shown. Figure 2A The top view of the inner lower structure 120 shown. Figure 2BAn inner frame locking portion 136 is shown on the proximal inner side of the inner frame lower structure 120. In some embodiments, the distal ends of the first proximal inner mounting arm 123 and the second proximal inner mounting arm 124 may be connected to the first transition lower structure portion 126 and the second transition lower structure portion 128, respectively. The first proximal inner mounting arm 123 may have a reduced lateral width relative to the first transition lower structure portion 126, and the second proximal inner mounting arm 124 may have a reduced lateral width relative to the second transition lower structure portion 128. In the example, the transition lower structures 126, 128 and the proximal inner mounting arms 123, 124 may be connected as follows: Figure 2B The narrowing is further shown at the narrowing transition area between the two elements.

[0039] In some embodiments, the inner frame locking portion 136 may be connected to a proximal tail including a first proximal tail end 148 and a second proximal tail end 150. The first proximal tail end 148 may be connected to a first proximal inner mounting arm 123, and the second proximal tail end 150 may be connected to a second proximal inner mounting arm 124.

[0040] As previously mentioned, each part of the lower structure 120 of the inner frame ( Figure 2A , 2B The high-density electrode mapping conduit, including proximal tail ends 148, 150, proximal medial mounting arms 123, 124, medial arm lower structures 121, 122, and expansion head 130, can be formed into a planar substrate. For example, the planar substrate may have a rectangular cross-section, which would be advantageous, as further described herein. In some methods, the high-density electrode mapping conduit can be assembled using tubular sub-assemblies for the medial and lateral lower structures. One reason for using tubing when assembling the lower structure is to allow wires to pass through the tubing for connecting the individual microelectrodes in a threaded manner. This process can be labor-intensive and / or cost-intensive, as each wire will be individually threaded through the tubing and individually connected to each microelectrode. Additionally, ensuring a reliable electrical connection between each microelectrode and its wires can be challenging.

[0041] Furthermore, the use of tubing can result in less predictability of the flexible tip deflection because the tubing walls can be symmetrical and not biased into bending in a specific form. Embodiments of the invention provide more predictable deflection of the flexible tip 110. Additionally, embodiments of the invention can maintain lateral spacing between multiple electrodes arranged on the inner and outer lower structures, as discussed further herein. However, byproducts of planar substrates (e.g., having a rectangular cross-section) can include contact between the edge of the arm and the damage-resistant coating accommodating the planar substrate, which can cause wear on the damage-resistant coating and ultimately lead to voids in the coating. Embodiments of the invention provide solutions to this potential event.

[0042] like Figure 2A and 2B As shown, the inner lower structure 120 (and the outer lower structure, although not shown) can be formed from a planar material piece. In the example, the inner lower structure 120 (and the outer lower structure) can be formed from a lower structure having a rectangular and / or square cross-section. In some embodiments, the inner lower structure 120 and / or the outer lower structure can be continuous elements formed from a single integral material piece. As used herein, a rectangular cross-section can be defined as a rectangular cross-section with a width greater than its thickness. However, in some embodiments, the rectangular cross-section may include a cross-section with a thickness greater than its width. As used herein, a square cross-section can be defined as a cross-section with the same width and thickness.

[0043] Figure 3 According to various embodiments of the present invention Figure 1A A top view of the outer lower structure 170 (also referred to herein as the outer lower structure) of the high-density electrode mapping catheter. In some embodiments, the outer lower structure 170 may be formed of a flexible or spring-like material (such as nitinol alloy) and / or a flexible substrate, as previously discussed with respect to the inner lower structure. The outer lower structure 170 may include a first outer arm lower structure 172 and a second outer arm lower structure 174. As shown, the outer lower structure 170 may include a first proximal outer mounting arm 176 and a second proximal outer mounting arm 178. The proximal outer mounting arms 176, 178 may be inserted into the distal end of the catheter 107 and may be used to attach a flexible tip 110 ( Figure 1A , 1B It is connected to the distal end of the conduit 107. In some embodiments, the proximal lateral mounting arms 176, 178 may be inserted through a torsion liner, as discussed herein.

[0044] In some embodiments, the outer lower structure 170 may define a head-end longitudinal axis as indicated by b'b'. In some embodiments, the outer lower structure 170 may be formed of a continuous element including a first rectangular cross-section. For example, the outer lower structure 170 may include a first proximal outer mounting arm 176 and a second proximal outer mounting arm 178, which may extend along the head-end longitudinal axis. The outer lower structure 170 may include a first outer arm lower structure 172 and a second outer arm lower structure 174, the first outer arm lower structure 172 extending distally from the first proximal outer mounting arm 176 and the second outer arm lower structure 174 extending distally from the second proximal outer mounting arm 178. In some embodiments, the first outer arm lower structure 172 and the second outer arm lower structure 174 may be parallel to the longitudinal axis b'b' and extend parallel to each other.

[0045] In some embodiments, a first outer transition lower structure 180 may be disposed between a first proximal outer mounting arm 176 and a first outer arm lower structure 172. The first outer transition lower structure 180 may expand laterally away from the head-end longitudinal axis b'b'. Furthermore, a second outer transition lower structure 181 may be disposed between a second proximal outer mounting arm 178 and a second outer arm lower structure 174. The second outer transition lower structure 181 may expand laterally away from the head-end longitudinal axis b'b'. In this example, the first outer transition lower structure 180 and the second outer transition lower structure 181 may expand away from each other.

[0046] In some embodiments, the outer lower structure 170 includes a distal head 182 connected to the first and second outer arm lower structures 172, 174. In some embodiments, the head 182 may be formed by a first narrowing element 184 and a second narrowing element 186, each extending distally toward the head-end longitudinal axis b'b' and converging at the longitudinal axis b'b'. In the example, the outer lower structure 170 may be symmetrical along the head-end longitudinal axis b'b'.

[0047] In some embodiments, the proximal portion of the lower outer frame structure 170 may include a first proximal lateral mounting arm 176 and a second proximal lateral mounting arm 178. In an example, the lower outer frame structure 170 may include an outer frame locking portion 188.

[0048] In some embodiments, the first proximal lateral mounting arm 176 and the second proximal lateral mounting arm 178 may be connected to the proximal ends of the first lateral transition lower structure 180 and the second lateral transition lower structure 181, respectively. The first proximal lateral mounting arm 176 may have a reduced lateral width relative to the first lateral transition lower structure 180, and the second proximal lateral mounting arm 178 may have a reduced lateral width relative to the second lateral transition lower structure 181. In the example, the lateral transition lower structures 180, 181 and the proximal lateral mounting arms 176, 178 may be narrowed at a narrowed lateral transition region located between the two elements.

[0049] In some embodiments, the proximal end of the outer frame locking portion 188 may be connected to a proximal outer tail end including a first proximal outer tail end 189 and a second proximal outer tail end 190. The first proximal outer tail end 189 may be connected to a first proximal outer mounting arm 176, and the second proximal outer tail end 190 may be connected to a second proximal outer mounting arm 178. In an example, the proximal outer mounting arms 176, 178 and the proximal outer tail ends 189, 190 may be narrowed at a narrowed outer tail end transition region located between the two elements.

[0050] As previously described, each portion of the outer frame lower structure 170, including the proximal tail ends 189, 190, the proximal outer mounting arms 176, 178, the outer arm lower structures 172, 174, and the head 182, can be formed from a planar substrate. For example, the planar substrate can have a rectangular cross-section, which would be advantageous, as further described herein. However, using a planar substrate can also result in the planar substrate having defined edges, as previously described. Figure 3 As shown, the outer lower structure 170 can be formed from a planar material piece. In the example, the outer lower structure 170 can be formed from a lower structure having a rectangular and / or square cross-section. In some embodiments, the outer lower structure 170 can be a continuous element formed from a single monolithic material piece.

[0051] Figure 4 According to various embodiments of the present invention Figure 2A and 2BThe diagram shows a top view of the inner lower structure 120' with an intermediate inner covering layer 200. As previously described, the inner lower structure 120' may include a first inner arm lower structure 121', a second inner arm lower structure 122', a first proximal inner mounting arm 123', and a second proximal inner mounting arm 124', which can be inserted into the distal end of the catheter to secure the inner lower structure to the catheter. The first proximal arm lower structure 121' may be connected to the first proximal inner mounting arm 123' via a first transition lower structure portion 126', and the second inner arm lower structure 122' may be connected to the second proximal inner mounting arm 124' via a second transition lower structure portion 128'.

[0052] The inner lower structure may include an expansion head 130' connected to the distal end of the first and second inner arm lower structures 121', 122'. The expansion head 130' may include a first expansion element 132' and a second expansion element 134'. As previously mentioned... Figure 2A and 2B As the first expansion element 132 and the second expansion element 134' extend distally, before extending toward the head end longitudinal axis bb'' and toward each other, the elements 132' and 134' can expand laterally away from the head end longitudinal axis bb and away from each other.

[0053] In some embodiments, the intermediate inner cladding layer 200 may be arranged around a continuous element forming the inner lower structure 120'. As previously described, the continuous element forming the inner lower structure 120' may be formed of a planar substrate. In some embodiments, the planar substrate may have a rectangular cross-section including a defining edge. The intermediate inner cladding layer 200 may be arranged around the continuous element to cover the defining edge of the inner lower structure, as previously described. In some embodiments, the intermediate inner cladding layer 200 may be arranged around a portion of a continuous element forming an expanding head 130'. The expanding head 130' may be defined as the distal end of the inner lower structure 120', which begins to expand laterally away from the head-end longitudinal axis b''b''. For example, the expanding head 130' in Figure 4 The portion shown is the lower inner structure to the left of the positioning line cc (e.g., the far side of line cc) (relative to the page).

[0054] In some embodiments, the inner lower structure 120' may not include the dilation head 130', but the intermediate inner overlay 200 may still be arranged around a portion of the continuous element forming the inner lower structure 120'. For example, the intermediate inner overlay 200 may be arranged over the entire continuous element or may be arranged partially over a portion of the continuous element. In some embodiments, the intermediate inner overlay 200 may be arranged on the portion of the inner lower structure 120' that is not inserted into the distal end of the catheter. For example, the intermediate inner overlay 200 may be arranged on the portion of the inner lower structure 120' that is not exposed and not located within the distal end of the catheter. In an example, the intermediate inner overlay may be arranged on the first transition lower structure portion 126' and / or the second transition lower structure portion 128'. In some embodiments, the intermediate inner covering layer may be disposed on the first transition lower structure 126' and / or the second transition lower structure 128', and on the portion of the inner lower structure 120' located distal to the first transition lower structure 126' and / or the second transition lower structure 128'. In some embodiments, the intermediate inner covering layer 200 may be disposed on the first inner arm lower structure 121' and the second inner arm lower structure 122', and on the portion of the inner lower structure 120' distal to the first inner arm lower structure 121' and the second inner arm lower structure 122'.

[0055] Such as about Figure 4 Furthermore, the intermediate inner cladding 200 may be arranged around the continuous element forming the expansion head 130'. In an example, the intermediate inner cladding 200 may be a tube that slides on a further portion of the expansion head 130' or the inner lower structure 120'. For example, the tube may slide on a first or second proximal inner mounting arm 123', 124'. The tube may be cylindrical, including a central cavity through which the continuous element forming the inner lower structure 120' can pass. The tube may slide along the continuous element until it is arranged along a portion of the continuous element forming the expansion head 130' or the inner lower structure 120'. In some embodiments, the tube may be a heat-shrink tubing. For example, the tube may be positioned along the portion of the continuous element forming the expansion head 130', and heat may be applied to the tube to shrink the tubing to form the intermediate inner cladding 200. In some embodiments, the intermediate inner cladding 200 may be a coating applied to the continuous element forming the expansion head 130'. In the example, the coating can be applied by immersing the inner lower structure 120' in paint and / or spraying the inner lower structure 120' with paint.

[0056] In some embodiments, the intermediate inner covering layer 200 may have two proximal ends 202-1, 202-2. As shown, the two proximal ends 202-1, 202-2 are shown positioned at the junction between the expanding head 130' and the lower structures 121', 122' of the first and second inner arms. For example, the two proximal ends 202-1, 202-2 may be positioned where the first expanding element 132' and the second expanding element 134' begin to expand laterally away from the longitudinal axis b''b'' of the head end. In some embodiments, and as shown, the proximal ends 202-1, 202-2 are positioned at the same longitudinal location along the long longitudinal axis b''b'' of the head end.

[0057] In some embodiments, the intermediate inner overlay layer 200 may include a layer of material (e.g., a polymer) that covers a portion of the lower structures 121', 122' of the first and / or second inner arms (e.g., the expanded head 130'). However, in some embodiments, the intermediate inner overlay layer 200 may include more than one layer of material that covers a portion of the lower structures 121', 122' of the first and / or second inner arms. In an example, a first material layer may cover a portion of the lower structures 121', 122' of the first and / or second inner arms, while a second material layer may be disposed on top of the first material layer. For example, a first heat-shrinkable material layer may be disposed on a portion of the lower structures 121', 122' of the first and / or second inner arms, and a second heat-shrinkable material layer may be disposed on top of the first heat-shrinkable material layer.

[0058] The intermediate inner cladding layer 200 can be used to increase the cross-sectional width of a continuous element and / or to cover the contoured edges of a planar substrate. For example, as further described herein, the contoured edges covered by the intermediate inner cladding layer may become less contoured, thus reducing the influence of tissues or other materials in contact with that edge.

[0059] Figure 5 According to various embodiments of the present invention Figure 3 The diagram shows a top view of the outer lower structure with a central outer overlay. As previously described, the outer lower structure 170' may include a first outer arm lower structure 172', a second outer arm lower structure 174', a first proximal outer mounting arm 176', and a second proximal outer mounting arm 178', which can be inserted into the distal end of the catheter to secure the inner lower structure to the catheter. The first outer arm lower structure 172' may be connected to the first proximal outer mounting arm 176' via a first outer transition lower structure portion 180', and the second outer arm lower structure 174' may be connected to the second proximal outer mounting arm 178' via a second outer transition lower structure portion 181'.

[0060] The outer lower structure 170 may include a head 182' connected to the distal end of the first and second outer arm lower structures 172', 174'. The head 182' may include a first narrowing element 184' and a second narrowing element 186'. As previously described... Figure 3 As the narrowing element 184' and the second narrowing element 186' extend distally, the elements 184' and 186' can each extend distally toward the head-end longitudinal axis b''b'' and intersect at the longitudinal axis b''b''.

[0061] In some embodiments, the intermediate outer cladding layer 210 may be arranged around a continuous element forming the outer lower structure 170'. As previously described, the continuous element forming the outer lower structure 170' may be formed of a planar substrate. In some embodiments, the planar substrate may have a rectangular cross-section including defining edges. The intermediate outer cladding layer 210 may be arranged around the continuous element to cover the contoured edges of the inner lower structure, as previously described. In some embodiments, the intermediate outer cladding layer 210 may be arranged around a portion of a continuous element forming a head 182'. The head 182' may be defined as the distal end of the outer lower structure 170', and the head 182' begins to narrow (e.g., converge) toward the head-end longitudinal axis b'''b'''. For example, the head 182' at Figure 5 The image shows a portion of the lower outer structure 170', which is positioned to the left (relative to the page) of line dd (e.g., the far side of line dd).

[0062] In some embodiments, the intermediate outer overlay 210 may be disposed over the entire continuous element forming the outer lower structure 170' or may be partially disposed over a portion of the continuous element. In some embodiments, the intermediate outer overlay 210 may be disposed over a portion of the outer lower structure 170' that is not inserted into the distal end of the catheter. For example, the intermediate outer overlay 210 may be disposed over an exposed portion of the outer lower structure 170' that is not located within the distal end of the catheter. In an example, the intermediate outer overlay may be disposed over the first proximal lateral mounting arm 176' and / or the second proximal lateral mounting arm 178'. In some embodiments, the intermediate outer overlay may be disposed over the first proximal lateral mounting arm 176' and / or the second proximal lateral mounting arm 178', and over a portion of the outer lower structure 170' located distal to the first proximal lateral mounting arm 176' and / or the second proximal lateral mounting arm 178'. In some embodiments, the intermediate outer covering layer 210 may be disposed on the portion of the first outer arm lower structure 172' and the second outer arm lower structure 174', as well as the portion of the outer lower structure 170' located distal to the first outer arm lower structure 172' and the second outer arm lower structure 174'.

[0063] like Figure 5As further shown, the intermediate outer covering 210 may be arranged around the continuous element forming the head 182'. In an example, the intermediate outer covering 210 may be a tube that slides on the head 182' or another portion of the outer lower structure 170'. For example, the tube may slide on the proximal end of one of the first or second proximal outer mounting arms 178', 176'. The tube may be cylindrical, including a central cavity through which the continuous element forming the outer lower structure 170' can pass. The tube may slide along the continuous element forming the outer lower structure 170' until it is arranged along a portion of the continuous element forming the head 182' and other portions of the outer lower structure 170'. In some embodiments, the tube may be formed of a polymer (e.g., polytetrafluoroethylene (PTFE)). In some embodiments, the tube may be a heat-shrink tubing. For example, the tube may be positioned along the continuous element forming the head 182', and heat may be applied to the tube to shrink the tubing to form the intermediate outer covering 210. In some embodiments, the intermediate outer covering layer 210 may be a coating applied to the continuous element forming the head 182'.

[0064] In some embodiments, the intermediate outer covering layer 210 may have two proximal ends 212-1, 212-2. As shown, the two proximal ends 212-1, 212-2 are shown positioned at the junction between the head 182' and the first and second outer lower structures 172', 174'. For example, the two proximal ends 212-1, 212-2 may be positioned where the first narrowing element 184' and the second narrowing element 186' begin to narrow toward the head end longitudinal axis b''b''. In some embodiments, as shown, the proximal ends 212-1, 212-2 are positioned at the same longitudinal location along the head end longitudinal axis b''b''.

[0065] The intermediate inner cladding layer 210 can be used to increase the cross-sectional width of a continuous element and / or to cover the sharply defined edges of a planar substrate. For example, as further described herein, the sharply defined edges covered by the intermediate inner cladding layer may become less defined, thus reducing the impact on tissues or other materials in contact with the edges.

[0066] Figure 6A This is a cross-sectional view of the covering layer arranged around the continuous elements of the inner lower structure according to various embodiments of the present invention. Figure 6AThe inner lower structure 220 is shown, as previously described. As further shown and as previously described, the inner lower structure 220 may have a rectangular cross-section, resulting in the inner lower structure 220 having a defined edge (e.g., a well-defined edge 224). In some embodiments, the covering layer 222 may be arranged around the inner lower structure 220. For example, the covering layer 222 may be arranged around a continuous element forming the inner lower structure 220. The covering layer 222 may extend along a longitudinal axis and may define a covering layer cavity 228, in some embodiments where the continuous element forming the inner lower structure 220 extends through the covering layer cavity.

[0067] As previously described, for example, the medial substructure 220 may contact the covering layer 222 due to folding caused by contact tissue and / or unfolding from the sheath. The main portion of the medial substructure 220 contacting the covering layer 220 may be a well-defined edge (e.g., a well-defined edge 224). Due to the contact between the medial substructure 220, and especially the well-defined edge 224, and the covering layer 222, a cavity is ultimately formed in the covering layer 222. In the example, the contact between the medial substructure 220 and the covering layer 222 may be concentrated in a contact area 226, defining the edge 224 in this area, causing the force exerted by the medial substructure 220 to concentrate on the covering layer 222 at the contact area 226. For ease of discussion, although... Figure 6A and 6B The described embodiment is also applied to the outer lower structure, but references the inner lower structure 220.

[0068] Figure 6B This is a cross-sectional view of an intermediate inner covering layer 230 arranged around a first continuous element of an inner lower structure 220' according to various embodiments of the present invention, with a covering layer 222' arranged around the inner lower structure 220' and the intermediate inner covering layer 230. In some embodiments, as described herein, the intermediate inner covering layer 230 may be arranged around a continuous element to cover a defined edge of the inner lower structure 220', as previously described. Accordingly, the contact between the inner lower structure 220' (e.g., a defined edge 224') and the covering layer 222' may be concentrated in a contact area 226', where a portion of the intermediate inner covering layer 230 covering the defined edge 224' may contact the covering layer 222, causing the force applied by the inner lower structure 220 to be concentrated on the covering layer 222 at the contact area 226'. Compared to Figure 6A The surface area of ​​the contact region 226' is greater than Figure 6AThe contact area 226 is shown. Accordingly, the force exerted on the cover layer 222' by the inner lower structure 220' is reduced relative to the force exerted on the cover layer 222 by the inner lower structure 220 (excluding the inner cover layer 230). Therefore, since the force exerted between the inner lower structure 220' and the inner cover layer 222' is distributed over a larger surface area, the amount of wear caused by the sharply defined edge 224' of the inner lower structure 220' on the cover layer 222' can be reduced.

[0069] Figure 7A This is a cross-sectional view of an intermediate covering layer 240 arranged around a lower structure 242 and a covering layer 244 arranged around the lower structure 242 and the intermediate inner covering layer 240 according to various embodiments of the present invention. Figures 7A to 7C The lower structure along lines ee and ff can be shown (e.g.) Figure 4 and 5 Cross-sectional views of those shown in the image. Further reference... Figure 7A The lower structure 242 may be an inner and / or outer lower structure, as described herein. In some embodiments, an intermediate overlay 240 may be arranged around the lower structure 242. For example, the intermediate overlay 240 may be a heat shrink tubing, and in some embodiments, the heat shrink tubing is arranged around the intermediate overlay 240. The lower structure 242 may slide through the inner cavity of the heat shrink tubing until the heat shrink tubing is properly positioned. In some embodiments, heat may be applied to the heat shrink tubing to cause the tubing to shrink around the lower structure 242. In some embodiments, the intermediate overlay 240 may also be a coating applied to the lower structure 242, as further described herein. In some embodiments, such as Figure 7A As shown, the covering layer 244 can be arranged around the intermediate covering layer 240 and the lower structure 242. In some embodiments, such as Figures 7A to 7C As shown, the overlay 244 can have an inner diameter ranging from 0.013 inches to 0.015 inches, although the overlay can have an inner diameter greater than or less than the defined range. Figure 7A As shown, the covering layer 244 can have an inner diameter of 0.014 inches. In some embodiments, such as Figures 7A to 7C As shown, the intermediate overlay 240 can have a wall thickness ranging from 0.001 inches to 0.003 inches, although the wall thickness of the intermediate overlay 240 can be greater than or less than the defined range. Figure 7A As shown, the intermediate cladding layer 240 can have a wall thickness of 0.002 inches. In some embodiments, such as Figures 7A to 7C As shown, the lower structure 242 can have a line W A W A The width is limited to the range of 0.0075 to 0.0085 inches, although the width of the lower structure 242 may be greater or less than the limited range. Figure 7A As shown, the lower structure 242 can have a width of 0.008 inches. In some embodiments, such as Figures 7A to 7C As shown, the lower structure 242 can have a line T A T A The thickness is limited to the range of 0.0055 to 0.0065 inches, although the thickness of the lower structure 242 may be less than or greater than the defined range. For example... Figure 7A As shown, the lower structure 242 can have a thickness of 0.006 inches.

[0070] Figures 7A to 7C The diagram shows gaps of different sizes between the outer surface of the intermediate covering layer 240 and the inner wall of the covering layer 244. (Refer to...) Figure 7A In some embodiments, the bottom gap between the outer bottom / top surface of the intermediate overlay 240 and the inner wall of the overlay 244 can be in the range of 0 to 0.004 inches, although the gap can be smaller or larger than the provided range. Figure 7A As shown, the bottom gap 246 can be 0.003 inches. In some embodiments, the side gap 248 between the outer surface of the intermediate overlay 240 and the inner wall of the overlay 244 can be 0 to 0.004 inches, although the gap can be smaller or larger than the provided range. Figure 7A As shown, the side clearance 248 can be 0.002 inches. In some embodiments, an interference fit can exist between the outer surface of the intermediate overlay 240 and the inner surface of the overlay 244, such as... Figure 7C Further details are provided.

[0071] Figure 7B This is a cross-sectional view of a lower structure 242', an intermediate covering layer 240' arranged around a first continuous element of the lower structure 242', and a covering layer 244' arranged around the lower structure 242' and the intermediate covering layer 240', according to various embodiments of the present invention. The lower structure 242' may be an inner and / or outer lower structure, as described herein. In some embodiments, the intermediate covering layer 240' may be arranged around the lower structure 242'. In some embodiments, the intermediate covering layer 240' may also be a tube and / or coating applied to the lower structure 242'. In some embodiments, such as Figure 7B As shown, the covering layer 244' can be arranged around the intermediate covering layer 240' and the lower structure 242'. Figure 7B As shown, the overlay 244' can have an inner diameter of 0.015 inches. (As...) Figure 7B As shown, the intermediate cladding layer 240' can have a wall thickness of 0.001 inches. (As...) Figure 7B As shown, the lower structure 242' can have a line W B W BA limited width of 0.0075 inches. Further details... Figure 7C As shown, the lower structure 242'' can have a structure composed of T C T C A limited thickness of 0.0055 inches. (e.g.) Figure 7B As shown, the bottom clearance 246' can be 0.004 inches. (As...) Figure 7B As shown, the side clearance 248' can be 0.003 inches.

[0072] Figure 7C This is a cross-sectional view of a lower structure 242'', an intermediate covering layer 240'' arranged around a first continuous element of the lower structure 242'', and a covering layer 244' arranged around the lower structure 242'' and the intermediate covering layer 240'', according to various embodiments of the present invention. The lower structure 242'' may be an inner and / or outer lower structure, as described herein. In some embodiments, the intermediate covering layer 240'' may also be a tube and / or coating applied to the lower structure 242''. In some embodiments, such as Figure 7C As shown, the covering layer 244' can be arranged around the intermediate covering layer 240'' and the lower structure 242''. Figure 7C As shown, the overlay 244'' can have an inner diameter of 0.013 inches. (As...) Figure 7C As shown, the intermediate overlay 242'' can have a thickness of 0.003 inches. (As...) Figure 7C As shown, the lower structure 242'' can have a line W C W C A limited width of 0.0085 inches. Further details... Figure 7C As shown, the lower structure 242'' can have a line T C T C A limited thickness of 0.0065 inches.

[0073] like Figure 7C As shown, the bottom gap 246'' can be 0 inches. In some embodiments, an interference fit may exist between the outer surface of the intermediate overlay 240'' and the inner surface of the overlay 244'', further as... Figure 7C As shown. For example, as illustrated, an interference fit may exist between the side surface of the outer surface of the intermediate covering layer 240'' and the inner surface of the covering layer 244''. For example, the width of the intermediate covering layer 240'' may exceed the width of the inner diameter of the covering layer 244''. Accordingly, the covering layer 244'' may be stretched on the intermediate covering layer 240''.

[0074] In some embodiments, such as Figures 7A to 7CAs shown, the intermediate overlay 240 can reduce the gap size between the inner walls of the lower structure 242 and the overlay 244. In some embodiments, reducing the gap size between the lower structure 242 and the inner walls of the overlay 244 can reduce the potential stretching / thinning of the overlay 244. For example, when a high-density mapping catheter including the lower structure 242 is folded as the catheter passes through a sheath, friction exists between the sheath and the outer overlay 244, which stretches the outer overlay. By introducing a smaller gap between the inner surfaces of the lower structure 242 and the overlay 244 via the intermediate overlay 240, the amount of friction between the overlay and the surface through which the catheter passes (e.g., the surface of the sheath) can be reduced. Additionally, the amount of necking (e.g., radial inward collapse) of the overlay 244 is reduced. Therefore, wear associated with the overlay 244 can be reduced.

[0075] Figure 7D It is a lower structure 242''' and a first inner intermediate covering layer 250 arranged around the lower structure 242''' according to various embodiments of the present invention, and has as Figure 7A A cross-sectional view of the second outer intermediate cladding layer 240''' with the first outer diameter shown. Figure 7D As shown, the first inner intermediate covering layer 250 can be arranged around the lower structure 242''', while the second outer intermediate covering layer 240''' can be arranged around the first inner intermediate covering layer 250 to create the first and second layers 250, 240''' of the covering layer, as described earlier in this document. (Refer to...) Figure 7D In some embodiments, the bottom gap 246''' between the outer bottom / top surface of the second outer intermediate overlay 240''' and the inner wall of the overlay 244''' can be in the range of 0 to 0.004 inches, although the gap can be smaller or larger than the provided range. Figure 7D As shown, the bottom clearance 246''' can be 0.003 inches, although the clearance size can be smaller or larger. For example, the clearance can be as shown in the figure regarding... Figure 7B and 7C Within the scope of the discussion. In some embodiments, the side clearance 248''' between the outer surface of the second outer intermediate covering layer 240''' and the inner wall of the covering layer 244''' can be in the range of 0 to 0.004. Figure 7A As shown, the side clearance 248''' can be 0.002 inches, although the clearance size can be smaller or larger. For example, the clearance can be as shown in the figure regarding... Figure 7B and 7C Within the scope of discussion.

[0076] In some embodiments, as previously described, the intermediate overlay may consist of more than one layer of material arranged around the lower structure 242'''. In an example, a first inner intermediate overlay 250 of material may cover the lower structure 242''', while a second outer intermediate overlay 240''' may be arranged on the first material layer. For example, a first heat-shrinkable material layer may be arranged on a portion of the lower structure 242''', and a second heat-shrinkable material layer may be arranged on the first heat-shrinkable material layer. In some embodiments, by including more than one layer of material covering a portion of the lower structure 242''', a larger diameter can be achieved, thereby reducing the amount of necking of the overlay 244'''.

[0077] This document describes embodiments of various devices, systems, and / or methods. Numerous specific details are set forth to provide a thorough understanding of the overall structure, function, manufacture, and use of the embodiments described in the specification and illustrated in the accompanying drawings. However, those skilled in the art will understand that the embodiments can be practiced without these specific details. In other instances, known operations, components, and elements have not been described in detail to avoid obscuring the embodiments described in the specification. Those skilled in the art will understand that the embodiments described and illustrated herein are non-limiting examples, and therefore it is understood that the specific structural and functional details disclosed herein may be representative and do not necessarily limit the scope of the embodiments, the scope of which is defined only by the appended claims.

[0078] Throughout this specification, references to "various embodiments," "some embodiments," "one embodiment," or "embodiment," etc., mean that a particular feature, structure, or characteristic described in connection with the said (or multiple) embodiments is included in at least one embodiment. Therefore, the appearance of the phrases "in various embodiments," "in some embodiments," "in one embodiment," or "in an embodiment," etc., in various places throughout this specification does not necessarily refer to the exact same embodiment. Furthermore, a particular feature, structure, or characteristic can be combined in any suitable manner in one or more embodiments. Therefore, a particular feature, structure, or characteristic shown or described in connection with one embodiment can be combined, in whole or in part, with features, structures, or characteristics of one or more other embodiments without limitation, provided that such combination is not illogical or nonfunctional.

[0079] It should be understood that the terms "proximal" and "distal" may be used throughout the instruction manual by a clinician manipulating one end of the instrument for treating a patient. The term "proximal" refers to the portion of the instrument closest to the clinician, while the term "distal" refers to the portion furthest from the clinician. It should also be understood that, for the sake of brevity and clarity, spatial terms such as "vertical," "horizontal," "upper," and "lower" may be used herein with respect to the embodiments shown. However, medical devices can be used in many orientations and positions, and these terms are not intended to be limiting or absolute.

[0080] While at least one embodiment of a multilayer high-density electrode mapping catheter has been described above with a degree of specificity, those skilled in the art can make various modifications to the disclosed embodiments without departing from the spirit or scope of the invention. All directional references (e.g., up, down, upward, downward, left, right, left-to-right, top, bottom, above, below, vertical, horizontal, clockwise, and counterclockwise) are used for illustrative purposes only to aid the reader's understanding of the invention and do not impose limitations, particularly regarding the location, orientation, or purpose of the device. Connection references (e.g., fixing, attaching, joining, connecting, etc.) should be interpreted broadly and may include intermediate members between connected elements and relative movement between elements. Thus, a connection reference does not necessarily refer to two elements being directly connected to each other and in a fixed relationship. It is intended that everything contained in the above description or shown in the drawings should be interpreted as illustrative rather than restrictive. Changes in detail or structure may be made without departing from the spirit of the invention as defined in the appended claims.

[0081] Any patent, disclosure, or other disclosure material considered to be incorporated herein by reference, in whole or in part, is incorporated herein only to the extent that it does not conflict with any existing definitions, statements, or other disclosures set forth herein. Thus, to the extent desired, the disclosure expressly set forth herein replaces any conflicting material incorporated herein by reference. Any material or portion thereof considered to be incorporated herein by reference but conflicting with any existing definitions, statements, or other disclosures set forth herein is incorporated only to the extent that the included material does not conflict with any existing disclosures.

Claims

1. A flexible catheter tip, comprising: The inner lower structure defines the longitudinal axis of the head end, wherein the inner lower structure includes a first rectangular cross-section; An inner intermediate covering layer is arranged around the lower inner structure. The inner intermediate covering layer is formed by more than one layer of material, wherein the material of the innermost first inner intermediate covering layer covers the lower inner structure, and the outermost second inner intermediate covering layer is arranged on the first material layer. An inner cladding layer is arranged around the inner lower structure and the intermediate inner cladding layer, the intermediate inner cladding layer being disposed between the inner lower structure and the inner cladding layer. An outer lower structure extending along the longitudinal axis of the head end, wherein the outer lower structure includes a second rectangular cross-section; and An intermediate outer covering layer is arranged around the outer lower structure. The intermediate outer covering layer is formed by more than one material layer, wherein the material of the innermost first intermediate outer covering layer covers the outer lower structure, and the outermost second intermediate outer covering layer is arranged on the first material layer. An outer covering layer is arranged around the outer lower structure, and an intermediate outer covering layer is arranged between the outer lower structure and the outer covering layer.

2. The flexible catheter tip according to claim 1, wherein the inner covering layer is arranged around most of the inner lower structure.

3. The flexible catheter tip according to claim 1, wherein the intermediate inner covering layer and the intermediate outer covering layer are formed of heat-shrinkable material.

4. The flexible catheter tip according to claim 1, wherein the inner lower structure comprises: A first proximal inner mounting arm and a second proximal inner mounting arm extending along the longitudinal axis of the head end; The lower structure of the first inner arm extending distally from the first proximal inner mounting arm; The lower structure of the second proximal arm extending distally from the second proximal inner mounting arm; and An expanded head connected to the distal ends of the first inner lower structure and the second inner lower structure.

5. The flexible catheter tip according to claim 1, wherein the first proximal inner mounting arm and the second proximal inner mounting arm are encapsulated in a damage-resistant coating, which may be a thin-walled polymer extrusion.

6. A flexible catheter tip, comprising: A flexible lower structure defining the longitudinal axis of the head end, wherein the flexible lower structure includes a first rectangular cross-section; An intermediate covering layer is arranged around the flexible lower structure. The intermediate covering layer is formed of more than one material layer, wherein the material of the innermost first intermediate covering layer covers the inner lower structure, and the material of the outermost second intermediate covering layer is arranged on the first material layer. An overlay layer is disposed on the intermediate overlay layer such that the intermediate overlay layer is disposed between the overlay layer and the flexible lower structure.

7. The flexible catheter tip according to claim 6 further includes a gap between the intermediate covering layer and the covering layer.

8. The flexible catheter tip according to claim 6, wherein there is an interference fit between the intermediate covering layer and the covering layer.

9. The flexible catheter tip of claim 6 further includes a gap between the intermediate overlay and the overlay, wherein the size of the gap is in the range of 0 to 0.004 inches.

10. The flexible catheter tip according to claim 6, wherein the intermediate overlay and the overlay are formed of one or more polymers.

11. The flexible catheter tip of claim 6, wherein the intermediate covering layer is formed of more than one layer of material and the more than one layer of material includes a heat-shrinkable material.

12. A flexible catheter tip, comprising: An inner lower structure defining the longitudinal axis of the head end, wherein the inner lower structure includes a first rectangular cross section, the inner lower structure defining a first inner arm lower structure and a second inner arm lower structure and an expanded head connected to the distal ends of the first inner arm lower structure and the second inner arm lower structure, respectively. An inner intermediate covering layer is arranged around the expansion head. This inner intermediate covering layer is formed by more than one layer of material, wherein the innermost first inner intermediate covering layer covers the inner lower structure, and the outermost second inner intermediate covering layer is arranged on the first material layer. An outer lower structure extending along the longitudinal axis of the head end, wherein the outer lower structure includes a second rectangular cross-section, the outer lower structure defining a first outer arm lower structure and a second outer arm lower structure, and a head connected to the distal ends of the first outer arm lower structure and the second outer arm lower structure, respectively; and A middle outer covering layer is arranged around a portion of the outer lower structure forming the head. The middle outer covering layer is formed of more than one layer of material, wherein the material of the innermost first middle outer covering layer covers the outer lower structure, and the outermost second middle outer covering layer is arranged on the first material layer. An inner cladding layer is arranged around the inner lower structure, and this inner cladding layer is arranged on the middle inner cladding layer, which is arranged between the inner cladding layer and the inner lower structure. An outer covering layer is arranged around the outer lower structure, the outer covering layer is arranged on the middle outer covering layer, and the middle outer covering layer is arranged between the outer covering layer and the outer lower structure.

13. The flexible catheter tip according to claim 12, wherein: The intermediate inner cladding layer includes a first proximal end and a second proximal end; and The first proximal end and the second proximal end are located at the junction of the expanded head and the lower structure of the first inner arm and the lower structure of the second inner arm.

14. The flexible catheter tip according to claim 13, wherein: The intermediate outer covering layer includes a first proximal end and a second proximal end; and The first proximal end and the second proximal end are located at the junction between the head and the lower structure of the first lateral arm and the lower structure of the second lateral arm.

15. The flexible catheter tip according to any one of claims 12 to 14, wherein the first proximal medial mounting arm and the second proximal medial mounting arm are encapsulated in a damage-resistant coating, which may be a thin-walled polymer extrusion.

Images