Microcatheters for interventional cardiovascular and / or neurovascular applications.

Abstract

A microcatheter (1) for interventional cardiovascular and / or neurovascular applications comprises a tubular catheter wall (2) comprising a proximal section (6), a first distal section (31), a second distal section (32), and a third distal section (33). The catheter wall (2) comprises a skeleton and an inner liner, the skeleton being a tubular reinforcing wall punctuated by a micro-machined cut pattern. The first distal section (31) has an overall skeleton cut-out ratio of at least 40%, the second distal section (32) has an overall skeleton cut-out ratio of at least 50%, and the third distal section (33) has an overall skeleton cut-out ratio of at least 60%. This application provides a solution for optimizing catheter flexibility while still maintaining the catheter's torqueability, pushability, and structural integrity when navigating deep within very fine, tortuous cardiovascular and neurovascular pathways.

Description

[Technical Field]

[0001] The present invention provides a catheter, which is a microcatheter for interventional cardiovascular and / or neurovascular applications, comprising: the catheter comprises a tubular catheter wall surrounding a luminal structure of the catheter, the catheter wall having a proximal end, a distal end, and a longitudinal direction extending from the proximal end to the distal end, the catheter wall having a length of at least 1000 mm along the longitudinal direction from the proximal end to the distal end; the catheter wall comprising: a proximal section defined to extend longitudinally distally from the proximal end to a first location 160 mm proximal to the distal end; and at least a first distal section defined to extend longitudinally distally from the first location to the distal end; At least a first distal section of the catheter wall comprises a scaffold, which is an interrupted tubular reinforcing wall obtained by micromachining a cut pattern into a completely uninterrupted tubular reinforcing wall made from a reinforcing material, and an inner liner, which is coaxially surrounded by the scaffold with respect to a centerline of the catheter wall; The catheter has a scaffold that provides reinforcement to the catheter wall both longitudinally and circumferentially about the longitudinal direction. [Background technology]

[0002] In such cardiovascular and neurovascular applications, such catheters must be angled through the tortuous bends and curves of vascular pathways to reach targeted anatomical structures. Such catheters require sufficient flexibility, particularly near their distal ends, to navigate such tortuous paths. However, other design aspects must also be considered. For example, the catheter must also be able to provide sufficient torqueability (i.e., the ability to transmit a torque applied at the proximal end to the distal end), pushability (i.e., the ability to transmit an axial push to the distal end), and structural integrity to perform its intended medical function.

[0003] US2019 / 0255290A1 discloses an example of an interventional cardiovascular catheter specifically designed for positioning near the aortic root in Figure 3. Figures 4A-4D and 5 of US2019 / 0255290A1 show several examples of scaffolds that can be applied to various longitudinal sections of the catheter of Figure 3 of US2019 / 0255290A1. Such scaffolds are interrupted tubular reinforcement walls obtained by micromachining a cut pattern into a completely uninterrupted tubular reinforcement wall made from a reinforcement material. The catheter of Figure 3 of US2019 / 0255290A1 is specifically designed to provide a relatively sharp bend 54 (see Figure 2 of US2019 / 0255290A1) for extending across the aortic root 16 to reach the artery 24 (see Figure 2 of US2019 / 0255290A1). In particular, the proximal-medial section 106 of FIG. 3 of US2019 / 0255290A1, which includes the single beam configuration of the skeleton of FIG. 4D of US2019 / 0255290A1, is designed to provide this relatively sharp bend 54.

[0004] The object of the present invention is to provide a solution for optimizing catheter flexibility while still maintaining the torqueability, pushability, and structural integrity of the catheter when navigating deep within very fine and tortuous cardiovascular and neurovascular pathways.

[0005] To that end, the present invention provides a catheter as set forth in the attached independent claim 1. Preferred embodiments of the invention are provided by the attached dependent claims 2-14.

[0006] The present invention therefore provides a catheter, which is a microcatheter for interventional cardiovascular and / or interventional neurovascular applications, comprising: the catheter comprises a tubular catheter wall surrounding a luminal structure of the catheter, the catheter wall having a proximal end, a distal end, and a longitudinal direction extending from the proximal end to the distal end, the catheter wall having a length of at least 1000 mm along the longitudinal direction from the proximal end to the distal end; The catheter wall a proximal section defined to extend longitudinally distally from the proximal end to a first location 160 mm proximal from the distal end; a first distal section defined to extend distally along a longitudinal direction from the first location to a distal end; a second distal segment that is defined to extend distally along a longitudinal direction from a second location to a distal end, the second location being 80 mm proximal to the distal end; and a third distal segment defined to extend distally along a longitudinal direction from a third position to a distal end, the third position being 40 mm proximal to the distal end; The catheter wall a scaffold, which is an interrupted tubular reinforcing wall obtained by micromachining a cut pattern into a completely non-intermittent tubular reinforcing wall made from a reinforcing material; an inner liner coaxially surrounded by the skeleton relative to the centerline of the catheter wall; the scaffold provides reinforcement for the catheter wall longitudinally and circumferentially about the longitudinal direction; the scaffold and the inner liner extend into at least a first distal section, a second distal section, and a third distal section; The total skeletal cutout ratio of the longitudinal section of the catheter wall in the longitudinal extent along the longitudinal direction is: - of the volume of all portions within the longitudinal extent of the reinforcing material that are cut from the completely uninterrupted tubular reinforcing wall according to the micro-machined cut pattern; - defined as the percentage of the volume of the completely uninterrupted tubular reinforcing wall relative to the volume of all portions of the reinforcing material within the longitudinal extent; The catheter is provided having a first distal section with an overall skeletal cutout ratio of at least 40%, a second distal section with an overall skeletal cutout ratio of at least 50%, and a third distal section with an overall skeletal cutout ratio of at least 60%.

[0007] Thus, an important feature of the present invention is - A total skeletal resection ratio of at least 40% in the first distal segment; - A total skeletal resection ratio of at least 50% in the second distal section; and - A total skeletal resection ratio of at least 60% in the third distal segment.

[0008] Thanks to these features, the microcatheter according to the invention exhibits a gradual increase in flexibility in the distal direction, at least in the most distal zone of the catheter, combined with very high flexibility in the third distal section. This combination of features makes it possible to optimize the flexibility of the catheter while still maintaining its torqueability, pushability, and structural integrity when navigating deep within very fine and tortuous cardiovascular and neurovascular pathways.

[0009] It should be noted that producing such a very high cut-out ratio (such as the very high cut-out ratio of 60% of the third distal section) according to the present invention requires the inventive measures to solve several problems in the present case, where the catheter in question is a microcatheter for interventional cardiovascular and / or interventional neurovascular applications, having the inner liner surrounded by the scaffold. This is because the inner liner for such cardiovascular and / or neurovascular applications is typically a tube made of, for example, PTFE (polytetrafluoroethylene, e.g., Teflon®), PVDF (polyvinylidene fluoride, e.g., Kynar®), or HDPE (high-density polyethylene), which is inserted axially into the scaffold during the manufacture of the microcatheter and then expanded relative to the scaffold by inflation and heat. Such a very high cut-out ratio can cause problems, for example, in that the tube made of PTFE, PVDF, or HDPE, which expands relative to the scaffold, protrudes from the large cut-out in the scaffold material and / or breaks under the inflation pressure. Another problem, especially with scaffolds made from weaker materials, is that the scaffold may deform significantly and / or crack and / or break under inflation pressure due to the fact that the scaffold is significantly weakened by large cutouts in the scaffold material.

[0010] In that regard, the present invention, inter alia, as disclosed herein, is based on the novel insight that the problem can be solved by temporarily introducing a heat-shrinkable outer tube on the outside of the scaffold during the manufacture of a catheter according to the present invention, the heat-shrinkable outer tube temporarily closing the cutouts in the scaffold material during said expansion of the inner liner due to inflation and heat, and at the same time, the heat-shrinkable outer tube temporarily stiffening the scaffold during said expansion of the inner liner due to inflation and heat. After the inner liner has been successfully expanded relative to the scaffold, and after the catheter under construction has cooled, the temporary heat-shrinkable outer tube can be removed from the outside of the scaffold and replaced with a final outer laminate on the outside of the scaffold, if desired.

[0011] More preferably, the total skeletal cutout ratio of the first distal section is at least 50%, the total skeletal cutout ratio of the second distal section is at least 60%, and the total skeletal cutout ratio of the third distal section is at least 70%.

[0012] Even more preferably, the total skeletal cutout ratio of the first distal section is at least 60%, the total skeletal cutout ratio of the second distal section is at least 70%, and the total skeletal cutout ratio of the third distal section is at least 80%.

[0013] In another preferred embodiment of a catheter according to the invention, wherein the first distal section has an overall skeletal cut-out ratio of at least 40%, the second distal section has an overall skeletal cut-out ratio of at least 50%, and the third distal section has an overall skeletal cut-out ratio of at least 60%, the catheter wall comprises: a fourth distal segment defined to extend distally along a longitudinal direction from a fourth position to a distal end, the fourth position being 20 mm proximal to the distal end; the scaffold and the inner liner further extend into a fourth distal section; The total skeletal cutout ratio of the fourth distal section is at least 70%. Thanks to these features, the microcatheter according to the invention, at least in the most distal zone of the catheter, exhibits an even more gradual increase in flexibility in the distal direction, combined with an even higher flexibility in said fourth distal section, which allows for even further optimization of the catheter's flexibility while still maintaining its torqueability, pushability, and structural integrity when navigating deep within very fine and tortuous cardiovascular and neurovascular pathways.

[0014] More preferably, in the most recently described preferred embodiment, the total skeletal cutout ratio of the first distal section is at least 50%, the total skeletal cutout ratio of the second distal section is at least 60%, the total skeletal cutout ratio of the third distal section is at least 70%, and the total skeletal cutout ratio of the fourth distal section is at least 80%.

[0015] Even more preferably, in the most recently described preferred embodiment, the total skeletal cutout ratio of the first distal section is at least 60%, the total skeletal cutout ratio of the second distal section is at least 70%, the total skeletal cutout ratio of the third distal section is at least 80%, and the total skeletal cutout ratio of the fourth distal section is at least 85%.

[0016] In yet another preferred embodiment of a catheter according to the invention, wherein the first distal section has an overall skeletal cut-out ratio of at least 40%, the second distal section has an overall skeletal cut-out ratio of at least 50%, and the third distal section has an overall skeletal cut-out ratio of at least 60%, the catheter wall comprises: a fourth distal segment defined to extend distally along a longitudinal direction from a fourth position to a distal end, the fourth position being 20 mm proximal to the distal end; and a fifth distal segment defined to extend distally along a longitudinal direction from a fifth position to a distal end, the fifth position being 10 mm proximal to the distal end; the scaffolding and the inner liner further extend into a fourth distal section and a fifth distal section; Thanks to these features, the fourth distal section has an overall skeletal cutout ratio of at least 70% and the fifth distal section has an overall skeletal cutout ratio of at least 80%, the microcatheter according to the invention exhibits an even more gradual increase in flexibility in the distal direction, at least in the most distal zone of the catheter, combined with an even higher flexibility in said fifth distal section, which allows for even further optimization of the catheter's flexibility while still maintaining its torqueability, pushability, and structural integrity when navigating deep within very fine and tortuous cardiovascular and neurovascular pathways.

[0017] More preferably, the total skeletal cutout ratio of the first distal section is at least 50%, the total skeletal cutout ratio of the second distal section is at least 60%, the total skeletal cutout ratio of the third distal section is at least 70%, the total skeletal cutout ratio of the fourth distal section is at least 80%, and the total skeletal cutout ratio of the fifth distal section is at least 85%.

[0018] Even more preferably, the total skeletal cutout ratio of the first distal section is at least 60%, the total skeletal cutout ratio of the second distal section is at least 70%, the total skeletal cutout ratio of the third distal section is at least 80%, the total skeletal cutout ratio of the fourth distal section is at least 85%, and the total skeletal cutout ratio of the fifth distal section is at least 90%.

[0019] In yet another preferred embodiment of a catheter according to the present invention, the inner liner extends distally beyond the skeleton to form an atraumatic distal tip of the catheter.

[0020] In yet another preferred embodiment of a catheter according to the invention, at least the first distal section of the catheter wall further comprises an outer laminate surrounding the scaffold coaxially relative to the centerline of the catheter wall.

[0021] More preferably, the outer laminate extends distally beyond the backbone to form an atraumatic distal tip of the catheter.

[0022] Even more preferably, the inner liner and outer laminate extend distally beyond the anatomy to form an atraumatic distal tip of the catheter.

[0023] In yet another preferred embodiment of a catheter according to the present invention, the intermittent tubular reinforcing wall frameworks each comprise at least one elongated reinforcing segment extending longitudinally along at least one corresponding longitudinal reinforcing path along the intermittent tubular reinforcing wall, wherein the thickness profile of at least one of the at least one elongated reinforcing segment gradually decreases when viewed distally along the longitudinal direction of the catheter wall, and the thickness of the at least one elongated reinforcing segment is defined to appear within the intermittent tubular reinforcing wall and perpendicular to the corresponding longitudinal reinforcing path. Thanks to these features, a microcatheter according to the present invention exhibits an even more gradual increase in flexibility in the distal direction, which allows even further optimization of catheter flexibility while still maintaining the torqueability, pushability, and structural integrity of the catheter when navigated deep within very fine, tortuous cardiovascular and neurovascular pathways.

[0024] In the following, the invention will be further elucidated with reference to non-limiting embodiments and with reference to the schematic diagrams of the accompanying drawings in which the following is shown: [Brief explanation of the drawings]

[0025] [Figure 1] 1 shows an example longitudinal side view of an embodiment of a catheter according to the present invention. [Figure 2A] 2 shows a short longitudinal section of the catheter of FIG. 1, the longitudinal section shown comprising part of the catheter's skeleton, and the view shown is a longitudinal cross-section through the centerline of the catheter wall of the catheter. [Figure 2B] 2B shows a cross section through the longitudinal section of FIG. 2A, the cross section shown being perpendicular to the centerline. [Figure 3A] The perspective views show first, second, third and fourth example embodiments of longitudinal sections of the skeletal portion of a catheter according to the invention, respectively. [Figure 3B] The perspective views show first, second, third and fourth example embodiments of longitudinal sections of the skeletal portion of a catheter according to the invention, respectively. [Figure 3C] The perspective views show first, second, third and fourth example embodiments of longitudinal sections of the skeletal portion of a catheter according to the invention, respectively. [Figure 3D] The perspective views show first, second, third and fourth example embodiments of longitudinal sections of the skeletal portion of a catheter according to the invention, respectively. [Figure 4A] 10A-10C show fifth, sixth, seventh, eighth, ninth, and tenth exemplary embodiments of longitudinal sections of a portion of a catheter skeleton according to the present invention, respectively, and the figures shown are top views of the longitudinal sections in their hypothetical "unrolled tube" state. To explain the term "unrolled tube," it should be noted that the skeleton according to the present invention is a tubular wall (more specifically, an intermittent tubular reinforcing wall), and that such a tubular wall can be unfolded into a hypothetical perfectly straight state by making a hypothetical linear cut parallel to the centerline along the entire length of the tubular wall and then unfolding it hypothetically onto a perfectly straight plane. [Figure 5A] 10A-10C show fifth, sixth, seventh, eighth, ninth, and tenth exemplary embodiments of longitudinal sections of a portion of a catheter skeleton according to the present invention, respectively, and the figures shown are top views of the longitudinal sections in their hypothetical "unrolled tube" state. To explain the term "unrolled tube," it should be noted that the skeleton according to the present invention is a tubular wall (more specifically, an intermittent tubular reinforcing wall), and that such a tubular wall can be unfolded into a hypothetical perfectly straight state by making a hypothetical linear cut parallel to the centerline along the entire length of the tubular wall and then unfolding it hypothetically onto a perfectly straight plane. [Figure 6A]10A-10C show fifth, sixth, seventh, eighth, ninth, and tenth exemplary embodiments of longitudinal sections of a portion of a catheter skeleton according to the present invention, respectively, and the figures shown are top views of the longitudinal sections in their hypothetical "unrolled tube" state. To explain the term "unrolled tube," it should be noted that the skeleton according to the present invention is a tubular wall (more specifically, an intermittent tubular reinforcing wall), and that such a tubular wall can be unfolded into a hypothetical perfectly straight state by making a hypothetical linear cut parallel to the centerline along the entire length of the tubular wall and then unfolding it hypothetically onto a perfectly straight plane. [Figure 7A] 10A-10C show fifth, sixth, seventh, eighth, ninth, and tenth exemplary embodiments of longitudinal sections of a portion of a catheter skeleton according to the present invention, respectively, and the figures shown are top views of the longitudinal sections in their hypothetical "unrolled tube" state. To explain the term "unrolled tube," it should be noted that the skeleton according to the present invention is a tubular wall (more specifically, an intermittent tubular reinforcing wall), and that such a tubular wall can be unfolded into a hypothetical perfectly straight state by making a hypothetical linear cut parallel to the centerline along the entire length of the tubular wall and then unfolding it hypothetically onto a perfectly straight plane. [Figure 8A] 10A-10C show fifth, sixth, seventh, eighth, ninth, and tenth exemplary embodiments of longitudinal sections of a portion of a catheter skeleton according to the present invention, respectively, and the figures shown are top views of the longitudinal sections in their hypothetical "unrolled tube" state. To explain the term "unrolled tube," it should be noted that the skeleton according to the present invention is a tubular wall (more specifically, an intermittent tubular reinforcing wall), and that such a tubular wall can be unfolded into a hypothetical perfectly straight state by making a hypothetical linear cut parallel to the centerline along the entire length of the tubular wall and then unfolding it hypothetically onto a perfectly straight plane. [Figure 9A]10A-10C show fifth, sixth, seventh, eighth, ninth, and tenth exemplary embodiments of longitudinal sections of a portion of a catheter skeleton according to the present invention, respectively, and the figures shown are top views of the longitudinal sections in their hypothetical "unrolled tube" state. To explain the term "unrolled tube," it should be noted that the skeleton according to the present invention is a tubular wall (more specifically, an intermittent tubular reinforcing wall), and that such a tubular wall can be unfolded into a hypothetical perfectly straight state by making a hypothetical linear cut parallel to the centerline along the entire length of the tubular wall and then unfolding it hypothetically onto a perfectly straight plane. [Figure 4B] The examples of Figures 4A, 5A, 6A, 7A, 8A, and 9A are again shown, respectively, but this time in perspective view in their actual tubular state. [Figure 5B] The examples of Figures 4A, 5A, 6A, 7A, 8A, and 9A are again shown, respectively, but this time in perspective view in their actual tubular state. [Figure 6B] The examples of Figures 4A, 5A, 6A, 7A, 8A, and 9A are again shown, respectively, but this time in perspective view in their actual tubular state. [Figure 7B] The examples of Figures 4A, 5A, 6A, 7A, 8A, and 9A are again shown, respectively, but this time in perspective view in their actual tubular state. [Figure 8B] The examples of Figures 4A, 5A, 6A, 7A, 8A, and 9A are again shown, respectively, but this time in perspective view in their actual tubular state. [Figure 9B] The examples of Figures 4A, 5A, 6A, 7A, 8A, and 9A are again shown, respectively, but this time in perspective view in their actual tubular state. [Figure 10] 11 shows an example of an eleventh embodiment of a longitudinal section of a portion of the skeleton of a catheter according to the present invention in a side view.

[0026] The reference numerals used in Figures 1-10 refer to the above-mentioned and related parts and aspects of the present invention as follows: 1--------------catheter 2--------------Tubular catheter wall 3--------------Lumen structure 4--------------proximal end 5--------------distal end 6--------------proximal division 7--------------Skeleton 7A------------Cutting pattern 8--------------Inner liner 9--------------Outer laminate 10------------Longitudinal direction 11------------Circumferential direction 12------------Center line 14, 15-------Elongated reinforcement section 16, 17-------Longitudinal reinforcement path 21------------First position 22------------Second position 23------------Third position 24------------4th position 25------------5th position 31------------First distal segment 32------------Second distal segment 33------------Third distal division 34------------Fourth distal division 35------------5th distal division 71 to 81--------First to eleventh embodiments of longitudinal sections of skeletal parts, respectively.

[0027] With regard to these reference numerals, it should be noted that in this disclosure, the same reference numerals may be used for similar parts or aspects among different embodiments or examples appearing in FIGS.

[0028] Based on the introductory discussion above, including a brief description of the drawings, and based on the above-listed reference numbers used in Figures 1-10, the examples of Figures 1-10 are, for the most part, readily self-explanatory. Additional explanation is provided below.

[0029] 1 shows the proximal section 6, the first distal section 31, the second distal section 32, the third distal section 33, the fourth distal section 34, and the fifth distal section 35 of the tubular catheter wall 2 of a catheter 1 according to the present invention. It becomes clear from FIG. 1 that the fifth distal section 35 is a distal subsection of the fourth distal section 34, which in turn is a distal subsection of the third distal section 33, which in turn is a distal subsection of the second distal section 32, which in turn is a distal subsection of the first distal section 31.

[0030] As mentioned above, in accordance with the present invention, at least the first distal section 31 of the catheter wall comprises a skeleton and an inner liner. It should also be noted that the proximal section 6 may also include a skeleton and an inner liner. In fact, the transition between the proximal section 6 and the first distal section 31 does not necessarily imply a transition in architecture between the proximal section 6 and the first distal section 31. Indeed, as used herein, the definition of a proximal section and first, second, third, fourth, and fifth distal sections merely serves to quantify a particular progression of the total skeleton cut ratio in the distal direction within the first distal section. In this quantification, the progression of the total skeleton cut ratio in the distal direction follows the occurring values ​​of the total skeleton cut ratio in the first, second, and third distal sections (or, as the case may be, the first, second, third, and fourth distal sections, or, as the case may be, the first, second, third, fourth, and fifth distal sections).

[0031] 2A-2B, it can be seen that the catheter wall 2 of the catheter 1 in the illustrated longitudinal section of the catheter 1 of FIG. 1 has a framework 7 that includes a cut pattern 7A. It can further be seen that the catheter wall 2 has an inner liner 8 and an outer liner 9. In the example of FIGS. 2A-2B, the lumen structure 3 of the catheter 1 is a single lumen structure. Alternatively, a catheter according to the present invention may have multiple lumen structures.

[0032] FIG. 3A shows that backbone 7 may be formed at least in part by the illustrated backbone structure 71, which consists of eight helices, four of which are right-handed helices and four of which are left-handed helices, with the four right-handed helices intersecting with the four left-handed helices at multiple nodes of backbone structure 71.

[0033] FIG. 3B shows that backbone 7 may be formed at least in part by the illustrated backbone structure 72, which consists of four helices, two of which are right-handed helices and two of which are left-handed helices, with the two right-handed helices intersecting with two left-handed helices at multiple nodes of backbone structure 72.

[0034] FIG. 3C shows that the skeleton 7 may be formed at least in part by the illustrated skeleton structure 73, which consists of parallel rings interconnected laterally in the axial direction by pairs of diametrically opposed spring-like connecting beams, with each successive axially successive beam pairs positioned at a 45 degree offset angle relative to each other in the circumferential direction about the axial direction.

[0035] FIG. 3D shows that the skeleton 7 may be formed at least in part by the illustrated skeleton structure 74, which consists of parallel rings interconnected laterally in the axial direction by single spring-like connecting beams, with each successive axial beam positioned at a 45 degree offset angle relative to one another in the circumferential direction about the axial direction.

[0036] Based on the skeleton portions 71, 72, 73, and 74 of Figures 3A-3D, respectively, the tubular catheter wall 2 of a catheter according to the present invention can have the following exemplary skeleton, purely by way of illustrative example: The exemplary skeleton first has an unbroken hypotube beginning at the proximal end 4 and having a length of 950 mm. The unbroken hypotube therefore terminates 950 mm distally from the proximal end 4. Note that as used herein, the term "unbroken hypotube" refers to a tubular skeleton having a 0% total skeleton cutout ratio. Next, starting 950 mm distally from the proximal end 4, the skeleton has the skeleton portion 71 of Figure 3A having a length of 300 mm, thus terminating 1250 mm distally from the proximal end 4. Next, starting 1250 mm distal to the proximal end 4, the skeleton has skeleton portion 72 of FIG. 3B having a length of 150 mm, thus terminating 1400 mm distal to the proximal end 4. Next, starting 1400 mm distal to the proximal end 4, the skeleton has skeleton portion 73 of FIG. 3C having a length of 20 mm, thus terminating 1420 mm distal to the proximal end 4. Next, starting 1420 mm distal to the proximal end 4, the skeleton has skeleton portion 74 of FIG. 3D having a length of 5 mm, thus terminating 1425 mm distal to the proximal end 4. The tubular catheter wall 2 having this exemplary skeleton may further include the inner liner 8 and outer laminate 9 described above along the entire length of the tubular catheter wall 2, with the inner liner 8 and outer laminate 9 extending distally beyond the skeleton to form the atraumatic distal tip of the catheter for a length of 5 mm distal to the distal end 5 of the tubular catheter wall 2, thus terminating 1430 mm distal to the proximal end 4.

[0037] 4-9 illustrate that the scaffold 7 can be formed at least in part by many different scaffold structures, such as the illustrated scaffold structures 75-80 of FIGS. 4-9, respectively.

[0038] 10 shows that the scaffold 7 may be formed at least in part by the illustrated scaffold structure 81, which consists of two helices, a right-handed helix 14 and a left-handed helix 15, that intersect each other at multiple nodes of the scaffold structure 81. In FIG. 10, the left-to-right direction corresponds to the distal direction along the longitudinal direction 10. Skeleton structure 81 is an example of a skeleton of a catheter according to the above-described preferred embodiment of the present invention, in which the skeleton comprises at least one elongated reinforcing portion (two spirals 14 and 15 in FIG. 10 ), each extending longitudinally along at least one corresponding longitudinal reinforcing path (paths 16 and 17 in FIG. 10 ) along the interrupted tubular reinforcing wall, and the thickness distribution of at least one of the at least one elongated reinforcing portion gradually decreases when viewed distally along the longitudinal direction of the catheter wall, and the thickness of the at least one elongated reinforcing portion is defined to appear within the interrupted tubular reinforcing wall and perpendicular to the corresponding longitudinal reinforcing path.

[0039] The present invention can be practiced with many different configurations, many different materials, many different shapes, and many different sizes of the catheter skeleton, inner liner, and outer laminate, as well as many different additional features and many different attachments to the catheter, such as those used in known microcatheters for interventional cardiovascular and / or neurovascular applications, as long as the catheter falls within the scope of the appended claims.

[0040] Furthermore, according to the present invention, it should be noted that typical dimensions of some portions and aspects of the present invention, as well as applicable practical ranges of such dimensions, are as follows: The effective length of the catheter (measured from the distal end of the catheter hub) may range from 130 cm to 160 cm, and may typically be 135 cm. The maximum outer diameter of the first distal section of the tubular catheter wall of the catheter may range from 0.60 mm to 1.20 mm, and may typically be 0.75 mm, but it should be noted that the term "maximum" in the term "maximum outer diameter" refers to the maximum value considered over the entire length of the first distal section. The minimum inner diameter of the first distal section of the tubular catheter wall of the catheter may range from 0.36 mm to 0.55 mm, and may typically be 0.45 mm, but it should be noted that the term "minimum" in the term "minimum inner diameter" refers to the minimum value considered over the entire length of the first distal section. For example, the following typical combinations of maximum outer diameter and minimum inner diameter of the first distal section are possible: A maximum outer diameter of 0.75 mm in combination with a minimum inner diameter of 0.45 mm, a maximum outer diameter of 1.20 mm in combination with a minimum inner diameter of 0.55 mm, or a maximum outer diameter of 0.60 mm in combination with a minimum inner diameter of 0.36 mm.

Claims

1. A catheter (1), which is a microcatheter for interventional cardiovascular and / or interventional neurovascular applications, comprising: The catheter comprises a tubular catheter wall (2) surrounding a luminal structure (3) of the catheter, the catheter wall having a proximal end (4), a distal end (5), and a longitudinal direction (10) extending from the proximal end to the distal end, the catheter wall having a length of at least 1000 mm from the proximal end to the distal end along the longitudinal direction; The catheter wall (2) a proximal section (6) defined to extend distally along said longitudinal direction from said proximal end (4) to a first position (21) 160 mm proximal from said distal end (5); a first distal section (31) defined to extend distally along said longitudinal direction from said first location to said distal end; a second distal section (32) defined to extend distally along the longitudinal direction from a second location (22) to the distal end (5), the second location (22) being 80 mm proximal to the distal end (5); a third distal section (33) defined to extend distally along said longitudinal direction from a third point (23) to said distal end (5), said third point (23) being 40 mm proximal to said distal end (5); The catheter wall (2) a scaffold (7) which is an interrupted tubular reinforcing wall obtained by micromachining a cut pattern (7A) into a completely uninterrupted tubular reinforcing wall made from a reinforcing material; an inner liner (8) coaxially surrounded by the skeleton (7) relative to the centerline (12) of the catheter wall (2); the skeleton (7) provides reinforcement for the catheter wall (2) in the longitudinal direction (10) and also in the circumferential direction (11) around the longitudinal direction (10); the skeleton (7) and the inner liner (8) extend within at least the first distal section (31), the second distal section (32), and the third distal section (33); The total skeletal cutout ratio of the longitudinal section of the catheter wall (2) in the longitudinal extent along the longitudinal direction (10) is: - of the volume of all portions within said longitudinal extent of said reinforcing material that are cut out from said completely uninterrupted tubular reinforcing wall according to said micromachined cut pattern (7A), - the volume of all parts of the completely uninterrupted tubular reinforcing wall within the longitudinal extent of the reinforcing material, A catheter (1), wherein the total skeletal cutout ratio of the first distal section (31) is at least 40%, the total skeletal cutout ratio of the second distal section (32) is at least 50%, and the total skeletal cutout ratio of the third distal section (33) is at least 60%.

2. 2. The catheter (1) of claim 1, wherein the total skeletal cutout ratio of the first distal section (31) is at least 50%, the total skeletal cutout ratio of the second distal section (32) is at least 60%, and the total skeletal cutout ratio of the third distal section (33) is at least 70%.

3. 3. The catheter (1) of claim 2, wherein the total skeletal cutout ratio of the first distal section (31) is at least 60%, the total skeletal cutout ratio of the second distal section (32) is at least 70%, and the total skeletal cutout ratio of the third distal section (33) is at least 80%.

4. The catheter wall (2) a fourth distal section (34) defined to extend distally along the longitudinal direction from a fourth position (24) to the distal end (5), the fourth position (24) being 20 mm proximal to the distal end (5); the skeleton (7) and the inner liner (8) further extend into the fourth distal section (34); The catheter (1) of claim 1, wherein the total skeletal cutout ratio of the fourth distal section (34) is at least 70%.

5. 5. The catheter (1) of claim 4, wherein the total skeletal cutout ratio of the first distal section (31) is at least 50%, the total skeletal cutout ratio of the second distal section (32) is at least 60%, the total skeletal cutout ratio of the third distal section (33) is at least 70%, and the total skeletal cutout ratio of the fourth distal section (34) is at least 80%.

6. 6. The catheter (1) of claim 5, wherein the total skeletal cutout ratio of the first distal section (31) is at least 60%, the total skeletal cutout ratio of the second distal section (32) is at least 70%, the total skeletal cutout ratio of the third distal section (33) is at least 80%, and the total skeletal cutout ratio of the fourth distal section (34) is at least 85%.

7. The catheter wall (2) a fourth distal section (34) defined to extend distally along the longitudinal direction from a fourth position (24) to the distal end (5), the fourth position (24) being 20 mm proximal to the distal end (5); a fifth distal section (35) defined to extend distally along said longitudinal direction (10) from a fifth position (25) to said distal end (5), said fifth position (25) being 10 mm proximal to said distal end (5); the skeleton (7) and the inner liner (8) further extend into the fourth distal section (34) and the fifth distal section (35); 2. The catheter (1) of claim 1, wherein the total skeletal cutout percentage of the fourth distal section (34) is at least 70% and the total skeletal cutout percentage of the fifth distal section (35) is at least 80%.

8. 8. The catheter (1) of claim 7, wherein the total skeletal cut-out ratio of the first distal section (31) is at least 50%, the total skeletal cut-out ratio of the second distal section (32) is at least 60%, the total skeletal cut-out ratio of the third distal section (33) is at least 70%, the total skeletal cut-out ratio of the fourth distal section (34) is at least 80%, and the total skeletal cut-out ratio of the fifth distal section (35) is at least 85%.

9. 9. The catheter (1) of claim 8, wherein the total skeletal cut-out ratio of the first distal section (31) is at least 60%, the total skeletal cut-out ratio of the second distal section (32) is at least 70%, the total skeletal cut-out ratio of the third distal section (33) is at least 80%, the total skeletal cut-out ratio of the fourth distal section (34) is at least 85%, and the total skeletal cut-out ratio of the fifth distal section (35) is at least 90%.

10. A catheter (1) according to any one of the preceding claims, wherein the inner liner (8) extends distally beyond the skeleton (7) to form an atraumatic distal tip of the catheter.

11. 10. The catheter (1) according to any one of the preceding claims, wherein at least the first distal section (31) of the catheter wall (2) further comprises an outer laminate (9) surrounding the skeleton (7) coaxially relative to the centerline (12) of the catheter wall.

12. The catheter (1) of claim 11, wherein the outer laminate extends distally beyond the backbone to form an atraumatic distal tip of the catheter.

13. 12. The catheter (1) of claim 11, wherein the inner liner (8) and the outer laminate (9) extend distally beyond the skeleton (7) to form an atraumatic distal tip of the catheter.

14. 10. The catheter (1) of claim 1, wherein the intermittent tubular reinforcing wall skeleton (81) comprises at least one elongated reinforcing portion (14, 15) extending longitudinally along at least one corresponding longitudinal reinforcing path (16, 17) along the intermittent tubular reinforcing wall, and wherein a thickness profile of at least one of the at least one elongated reinforcing portion (14, 15) gradually decreases when viewed distally along the longitudinal direction (10) of the catheter wall (2), and wherein the thickness of the at least one elongated reinforcing portion (14, 15) is defined to appear within the intermittent tubular reinforcing wall and perpendicular to the corresponding longitudinal reinforcing path (16, 17).

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