Catheter device

Abstract

This catheter device is provided with a catheter shaft (30) having: an inner layer (50) that forms a main lumen (40) having a substantially circular cross-sectional shape; and an outer layer (52) that is provided on the outside of the inner layer (50) and forms a sub-cavity (42). The sub-cavity (42) has a cross-sectional shape curved along the main cavity (40) and having a substantially uniform thickness (t) in the circumferential direction.

Description

Technical Field

[0001] This invention relates to a catheter device. Background Technology

[0002] Previously, catheter devices with a multi-lumen structure having a main lumen and a secondary lumen were known. The structure of the main lumen and the secondary lumen was mainly determined by their cross-sectional shapes. The mainstream cross-sectional shape of the main lumen was approximately circular, but the cross-sectional shapes of the secondary lumen were varied. For example, Patent Document 1 disclosed a catheter shaft with a secondary lumen having a rectangular cross-section. Furthermore, Patent Document 2 disclosed a catheter shaft with a secondary lumen having a crescent-shaped cross-section. Moreover, Patent Document 3 disclosed a catheter shaft with a secondary lumen having an elliptical cross-section with a curved cross-section.

[0003] Patent Document 1: International Publication No. 2022 / 085199

[0004] Patent Document 2: Japanese Patent Publication No. 2001-508670

[0005] Patent Document 3: Japanese Patent Application Publication No. 2013-66720 Summary of the Invention

[0006] The purpose of this invention is to provide a catheter device with a new cross-sectional shape of a lumen that differs from the existing lumen described above.

[0007] To address the aforementioned technical problems, a catheter device according to a certain embodiment of the present invention includes a catheter shaft having: an inner layer forming a main lumen with a generally circular cross-sectional shape; and an outer layer disposed outside the inner layer, forming a secondary lumen. The secondary lumen has a cross-sectional shape that curves along the main lumen and has a generally uniform thickness in the circumferential direction.

[0008] According to the present invention, a catheter device having a new profile shape of a lumen that differs from existing lumen devices can be provided. Attached Figure Description

[0009] Figure 1 This is a schematic diagram illustrating an example of a scenario in which the conduit device of the embodiment is used.

[0010] Figure 2 This is an overall diagram showing the conduit device of the embodiment.

[0011] Figure 3 It is a cross-sectional view perpendicular to the extension direction of the conduit axis in the embodiment.

[0012] Figure 4 This is an enlarged view of the secondary cavity.

[0013] Figure 5 This is an enlarged view of the end of the secondary cavity.

[0014] Figure 6 This is a cross-sectional view showing another embodiment of the conduit shaft.

[0015] Figure 7 This is a diagram used to illustrate the conditions for defining the circumferential length of the secondary cavity.

[0016] Figure 8 This is a diagram illustrating the conduit shaft in other embodiments. Detailed Implementation

[0017] The embodiments for carrying out the present invention will be described below. Identical or equivalent components are labeled with the same reference numerals, and repeated descriptions are omitted. In each drawing, components are appropriately omitted, enlarged, or reduced for ease of explanation. The drawings are viewed according to the orientation of the reference numerals.

[0018] Figure 1 This is a schematic diagram illustrating an example of the application scenario of the catheter device 10 according to the embodiment. The catheter device 10 is inserted into the target organ 12 of a living organism for the treatment of the target organ 12. Here, "treatment" refers to actions related to the treatment or examination of a living organism. Here, as such treatment, the case where a medical device is guided to the target organ 12 for the treatment or examination of the target organ 12 will be described. The target organ 12 is, for example, a circulatory organ, a digestive organ, etc. Circulatory organs that are target organs 12 include, for example, the common carotid artery, external carotid artery, internal carotid artery, subclavian artery, brachiocephalic artery, vertebral artery, etc. The catheter device 10 of this embodiment is used in the TRN (Transradial Neuro-intervention) method. In this case, the catheter device 10 is inserted via the radial artery 14 into the cerebral blood vessels (external carotid artery, internal carotid artery, etc.) that are the target organ 12. Here, an example is shown where the catheter device 10 is inserted via the radial artery 14, the right subclavian artery 16, and the aorta 18 into the left common carotid artery 20, which is the target organ 12.

[0019] Figure 2 This is an overall view showing the catheter device 10 according to the embodiment. The catheter device 10 includes a catheter shaft 30 and a handle 32 mounted on the base end of the catheter shaft 30. As an optional configuration, the catheter shaft 30 includes a balloon 34 attached to the tip of the catheter shaft 30.

[0020] The catheter shaft 30 is flexible and can be bent and deformed. The catheter shaft 30 of this embodiment has a bend 30a provided in the middle part of its axial direction. A tip member 36 is installed at the top end of the catheter shaft 30. When the target organ 12 is a blood vessel such as a cerebral blood vessel, the outer diameter of the catheter shaft 30 is, for example, 9.5Fr (3.2 mm) or less.

[0021] The handle 32 is held by the surgeon or other operator. The handle 32 has a main inlet port 32a that communicates with the main lumen of the catheter shaft 30 and a secondary inlet port 32b that communicates with the secondary lumen of the catheter shaft 30.

[0022] The balloon 34 can be expanded by supplying fluid through the secondary lumen of the catheter shaft 30 to the interior. The balloon 34 is used to temporarily cut off blood flow by expanding within the blood vessel that is the target organ 12.

[0023] Figure 3 yes Figure 2 The AA sectional view shows a section perpendicular to the extension direction (axial direction) of the catheter shaft 30. Hereinafter, when describing the positional relationships and shapes of the constituent elements of the catheter shaft 30, the positional relationships and shapes at the section perpendicular to the axial direction of the catheter shaft 30 will be described unless otherwise specified.

[0024] A main lumen 40 and a secondary lumen 42 are formed in the catheter shaft 30. In the cross-section of the catheter shaft 30, the cross-sectional area of ​​the main lumen 40 is larger than that of the secondary lumen 42. In this embodiment, the cross-sectional shape of the main lumen 40 is circular.

[0025] The main lumen 40 and the secondary lumen 42 are respectively for passage of at least one of a medical device or a fluid. In this embodiment, the main lumen 40 is used for passage of the medical device to guide the medical device to the target organ 12. In this embodiment, the secondary lumen 42 is used for passage of fluid for expanding the balloon 34.

[0026] The medical devices that should pass through the cavities 40 and 42 include, for example, various catheters such as electrode catheters, balloon catheters, and microcatheters, in addition to covered stents, coils, guidewires, and wiring components. The wiring components here refer, for example, to flexible substrates for wiring that are electrically connected to electrical equipment mounted on the catheter shaft 30. The electrical equipment here is, for example, an ultrasound transducer used in ICE (Intracardiac Echocardiography). The fluids that should pass through the cavities 40 and 42 include, for example, liquids such as contrast agents and flushing fluids (such as saline), in addition to gas used to expand the balloon 34.

[0027] An object that should pass through the main lumen 40 is introduced from outside the body into the main lumen 40 through the main inlet port 32a of the handle 32, and is then discharged into the body through the main outlet port 46 provided in the catheter device 10. The main outlet port 46 is provided, for example, in the tip member 36 (see reference). Figure 2 An object to be passed through the secondary lumen 42 is introduced from outside the body into the secondary lumen 42 through the secondary inlet port 32b of the handle 32, and is then exited into the balloon 34 through the secondary outlet port 48 provided on the catheter device 10. The secondary outlet port 48 is, for example, formed as a side hole opening into the outer peripheral surface of the catheter shaft 30 at the location where the balloon 34 is attached (see reference). Figure 2 ).

[0028] The catheter shaft 30 includes: an inner layer 50 forming a main lumen 40; and an outer layer 52 disposed outside the inner layer 50, forming a secondary lumen 42. The catheter shaft 30 of this embodiment also includes a reinforcing layer 54 disposed between the inner layer 50 and the outer layer 52. That is, a reinforcing layer 54 is provided outside the main lumen 40. The inner layer 50 and the outer layer 52 are composed of at least one resin layer. The inner layer 50, the outer layer 52, and the reinforcing layer 54 can be formed from the base end to the tip end of the catheter shaft 30. Alternatively, a different type of material can be used. Figure 3 The shaft with the cross-sectional shape shown extends to the middle of the guide shaft 30, and is then fused with other tubes from the middle for use.

[0029] The inner layer 50 can be made from synthetic resins such as PTFE (polytetrafluoroethylene) and PFA (perfluoroalkoxyalkane), which have good sliding properties, or fluorinated resins. The resin layer constituting the outer layer 52 can be made from synthetic resins such as PA, PA-based elastomers, and TPU.

[0030] The reinforcing layer 54 is composed of a braided piece obtained by braiding multiple wires (not shown) into a tubular shape. Alternatively, the reinforcing layer 54 may also be composed of coils made of single or multiple wires (not shown). The reinforcing layer 54 has the function of improving the torque transmission and torsion resistance of the guide shaft 30. Torque transmission here refers to the characteristic of transmitting the torque applied to the handle 32 to the tip of the guide shaft 30. To achieve this, the reinforcing layer 54 is configured to cover the inner layer 50 of the guide shaft 30. The wires constituting the reinforcing layer 54 may be made of metals such as stainless steel and Ni-Ti alloy, or resin, etc. In this embodiment, the wires are circular in cross-sectional shape orthogonal to their axial direction. The cross-sectional shape of the wires is not particularly limited; for example, they may be flat.

[0031] In the catheter shaft 30 of this embodiment, no reinforcing layer is provided on the outer side of the outer layer 52. That is, no reinforcing layer is provided on the outer side of the secondary lumen 42. As a result, a smaller outer diameter of the catheter shaft 30 can be achieved. Furthermore, the absence of a reinforcing layer on the outer side of the secondary lumen 42 is advantageous when the internal pressure of the secondary lumen 42 is made negative, or when the secondary lumen 42 is flattened by applying external force, etc. The case of flattening the secondary lumen 42 will be described later.

[0032] like Figure 3As shown, the cross-sectional shapes of the catheter shaft 30 and the main lumen 40 are approximately circular. The center C40 of the main lumen 40 is eccentrically positioned relative to the center C30 of the catheter shaft 30 in an eccentric direction D1. The direction opposite to the eccentric direction D1 relative to the center C30 of the catheter shaft 30 is called the anti-eccentric direction D2. At this time, the secondary lumen 42 is formed relative to the main lumen 40 in the anti-eccentric direction D2. The secondary lumen 42 is not formed relative to the center C40 of the main lumen 40 in the eccentric direction D1. The diameter of the main lumen 40 can be, for example, more than 80% of the diameter of the catheter shaft 30. Furthermore, the space consisting of the diameter of the main lumen 40 and the thickness t of the secondary lumen 42 can be, for example, more than 85% of the diameter of the catheter shaft 30.

[0033] Figure 4 This is an enlarged view of the secondary cavity 42. The secondary cavity 42 is enclosed by the outer layer 52. The secondary cavity 42 has a cross-sectional shape that curves along the main cavity 40 and has a substantially uniform thickness t in the circumferential direction. Here, "substantially uniform thickness t" means that the maximum and minimum values ​​of the thickness t are within ±15% of the average value of the thickness t, more preferably within ±10%. The average value of the thickness t can be obtained, for example, by dividing the secondary cavity 42 into three equal parts in the width direction and averaging the thickness t of each part. The thickness t can be, for example, the thickness measured by a digital microscope. The thickness t can be substantially uniform from one end of the secondary cavity 42 to the other end. Alternatively, the thickness t can also be substantially uniform within 80% of the circumferential length of the secondary cavity 42. The thickness t of the secondary cavity 42 can be, for example, less than 0.5 mm, preferably less than 0.3 mm, more preferably less than 0.2 mm.

[0034] The secondary cavity 42 is defined by an outer arc-shaped edge 42a located on the outer side in the radial direction, an inner arc-shaped edge 42b located on the inner side in the radial direction, a first end edge 42c located at one end in the circumferential direction, and a second end edge 42d located at the other end in the circumferential direction.

[0035] In this embodiment, the secondary cavity 42 is formed such that the length of the outer arcuate side 42a is approximately equal to the length of the inner arcuate side 42b. Here, "approximately equal" means that the length of the inner arcuate side 42b is within ±5% of the length of the outer arcuate side 42a, more preferably within ±3%. Furthermore, in this embodiment, the secondary cavity 42 is formed such that the outer arcuate side 42a and the inner arcuate side 42b are not concentric. In this way, by forming the secondary cavity 42, a secondary cavity 42 with a cross-sectional shape that curves along the main cavity 40 and has a substantially uniform thickness t in the circumferential direction can be achieved. The lengths of the outer arcuate side 42a and the inner arcuate side 42b can, for example, be more than 1 / 4 of the circumference of the catheter shaft 30.

[0036] In the present embodiment, the magnitude relationship between the thickness A of the layer located outside the subchamber 42 and the thickness B of the layer located inside the subchamber 42 remains unchanged within the circumferential (extending direction) range of the subchamber 42. The thickness A of the layer located outside the subchamber 42 refers to the shortest distance from the outer arc-shaped edge 42a to the outer peripheral surface of the outer layer 52. The thickness B of the layer located inside the subchamber 42 refers to the shortest distance from the inner arc-shaped edge 42b to the inner peripheral surface of the inner layer 50. It is sufficient that the magnitude relationship between the thickness A and the thickness B remains unchanged within 80% of the circumferential length of the subchamber 42. Alternatively, the magnitude relationship between the thickness A and the thickness B may remain unchanged from one end portion to the other end portion in the circumferential direction of the subchamber 42. The thickness A of the layer located outside the subchamber 42 can be, for example, 0.2 mm or less.

[0037] In Figure 4 the thicknesses A1, B1 are shown at one end in the circumferential direction of the subchamber 42, the thicknesses A2, B2 are shown at the center, and the thicknesses A3, B3 are shown at the other end. The fact that the magnitude relationship between the thickness A and the thickness B remains unchanged from one end portion to the other end portion of the subchamber 42 means that when A1 > B1, A2 > B2 and A3 > B3, and conversely when A1 < B1, A2 < B2 and A3 < B3. Combinations where the magnitude relationship is different, such as A1 > B1, A2 < B2, A3 > B3, are not allowed.

[0038] Figure 5 is an enlarged view of the end portion of the subchamber 42. As Figure 5 shown, the first end edge 42c located at one end portion in the circumferential direction of the subchamber 42 has a shape formed by combining an arc 60 and a straight line 62. Similarly, the second end edge 42d located at the other end portion in the circumferential direction of the subchamber 42 also has a shape formed by combining an arc and a straight line.

[0039] Here, a line obtained by extending the straight line 62 at the first end edge 42c of the subchamber 42 is set as the first extension line 64, and a line obtained by extending the straight line at the second end edge 42d of the subchamber 42 is set as the second extension line 66. At this time, in the catheter shaft 30 of the present embodiment, as Figure 3 shown, the first extension line 64 and the second extension line 66 do not pass through the center C30 of the catheter shaft 30. Moreover, in the catheter shaft 30 of the present embodiment, when viewed from the midpoint C42 of the subchamber 42, the intersection point 68 of the first extension line 64 and the second extension line 66 is located at a position farther from the center C30 of the catheter shaft 30.

[0040] In Figure 3 the intersection point 68 of the first extension line 64 and the second extension line 66 coincides with the center C40 of the main chamber 40, but depending on the orientation of the straight line 62 forming the first end edge 42c and the second end edge 42d, there are cases where the intersection point 68 does not coincide with the center C40 of the main chamber 40. Figure 6This illustrates an example where the intersection point 68 of the first extension line 64 and the second extension line 66 is not aligned with the center C40 of the main cavity 40. Figure 6 In one embodiment, when viewed from the midpoint C42 of the secondary lumen 42, the intersection 68 of the first extension line 64 and the second extension line 66 is located further than the center C30 of the catheter shaft 30 and the center C40 of the main lumen 40.

[0041] Figure 7 This is a diagram used to illustrate the conditions for defining the circumferential length of the secondary cavity 42. For example... Figure 7 As shown, at the midpoint C42 of the circumference of the secondary cavity 42, a reference line L is drawn that is perpendicular to the inner arc-shaped edge 42b. At this time, the two ends of the secondary cavity 42 (the first end edge 42c and the second end edge 42d) are located further inward than the reference line L (in... Figure 7 The middle part is located below the baseline L. That is, the secondary cavity 42 is formed with both ends located at... Figure 7 Within the range indicated by the blank arrow 70. By determining such conditions, the minimum circumferential length of the secondary cavity 42 can be defined.

[0042] In the catheter device 10, the secondary lumen 42 can be flattened by controlling the internal pressure of the secondary lumen 42 to a negative pressure. Alternatively, even without making the secondary lumen 42 negative, it can be flattened by applying force from the outside of the shaft at the insertion port or inside the body when it is to be inserted. "Flattening the secondary lumen 42" means that the outer layer 52 located outside the secondary lumen 42 deforms radially inward, so that the outer arc-shaped edge 42a of the secondary lumen 42 partially contacts the inner arc-shaped edge 42b, thereby reducing the shaft diameter. This helps to reduce the outer diameter of the catheter shaft 30 and facilitates the realization of a small catheter device 10 during insertion and withdrawal. A certain circumferential length is required to properly flatten the secondary lumen 42. By using the reference line L to define the positions of the two ends of the secondary lumen 42, the circumferential length of the secondary lumen 42 can be ensured, thereby allowing for proper flattening of the secondary lumen 42 based on negative pressure.

[0043] Figure 8 This is a diagram illustrating the conduit shaft 30 in other embodiments. The conduit shaft 30 of this embodiment can be used in situations where it is desirable to maintain the shape of the shaft and ensure the passage of fluid flowing in the secondary cavity 42.

[0044] like Figure 8As shown, in the catheter shaft 30 of this embodiment, the outer layer 52 has a rib 56 protruding from the outer arcuate edge 42a of the secondary lumen 42 toward the inner arcuate edge 42b. By forming such a rib 56, when the internal pressure of the secondary lumen 42 is negative, complete blockage of the secondary lumen 42 can be prevented, thus maintaining the shape of the shaft and ensuring the passage of fluid flowing in the secondary lumen 42. The rib 56 can be formed to protrude from the inner arcuate edge 42b toward the outer arcuate edge 42a. That is, the rib 56 can also be formed to protrude from one of the outer arcuate edge 42a and the inner arcuate edge 42b toward the other.

[0045] exist Figure 8 In this design, ribs 56 are positioned at three locations: the center of the secondary cavity 42 and near both ends. However, the number and position of the ribs 56 are not particularly limited. The height h of the ribs 56 is set to a dimension that does not contact the opposing surface, and can be 30% to 80% of the thickness t of the secondary cavity 42, preferably 40% to 60%, for example, 50%. It should be noted that, in the above description, the secondary cavity 42 has a cross-sectional shape with a substantially uniform thickness t in the circumferential direction, but it should be noted that the portion in which the ribs 56 are formed is not limited to this.

[0046] The configuration of the secondary lumen 42 of the catheter device 10 of this embodiment has been described in detail above. The secondary lumen 42 of this embodiment has a new cross-sectional shape that is different from the secondary lumen of conventional catheter devices.

[0047] As described above, the secondary cavity 42 of this embodiment has a cross-sectional shape that curves along the main cavity 40 and has a substantially uniform thickness t in the circumferential direction. For example, regarding the crescent-shaped secondary cavity disclosed in Patent Document 2 above, the thickness of the cavity decreases towards the end, and the fluid resistance increases. By making the thickness t substantially uniform in the circumferential direction, the secondary cavity 42 of this embodiment can achieve a uniform fluid resistance in the circumferential direction. This facilitates smooth fluid flow in the secondary cavity 42.

[0048] Furthermore, for example, regarding the rectangular cross-section of the secondary cavity disclosed in Patent Document 1, to ensure the required cross-sectional area of ​​the secondary cavity, the thickness of the secondary cavity must be increased, which may increase the outer diameter of the conduit shaft. According to the secondary cavity 42 of this embodiment, by having a cross-sectional shape that curves along the main cavity 40 and has a substantially uniform thickness t in the circumferential direction, the required cross-sectional area of ​​the secondary cavity can be ensured without increasing the outer diameter of the conduit shaft 30.

[0049] The above embodiments and variations are examples. The technical ideas derived from their abstraction should not be limited to the contents of the embodiments and variations. The contents of the embodiments and variations can undergo many design changes, such as altering, adding, or deleting constituent elements. In the embodiments described, the phrase "embodiment" is added to emphasize the content that allows such design changes. However, design changes are permitted even without such a phrase. The shaded lines in the cross-sections of the accompanying drawings do not limit the material of the objects marked with shaded lines. The structures and values ​​mentioned in the embodiments and variations naturally include those that can be considered the same when considering manufacturing errors, etc.

[0050] Industrial availability

[0051] This invention can be used in catheter devices.

[0052] Explanation of reference numerals in the attached figures

[0053] 10: Catheter device; 30: Catheter shaft; 32: Handle; 34: Balloon; 36: Tip component; 40: Main lumen; 42: Secondary lumen; 46: Main exit port; 48: Secondary exit port; 50: Inner layer; 52: Outer layer; 54: Reinforcing layer; 56: Rib.

Claims

1. A catheter device, characterized in that, It has a catheter shaft, the catheter shaft having: The inner layer forms a main cavity with a roughly circular cross-sectional shape; and The outer layer, located outside the inner layer, forms a secondary cavity. The secondary cavity has a cross-sectional shape that curves along the main cavity and has a generally uniform thickness in the circumferential direction.

2. The catheter device according to claim 1, characterized in that, The thickness of the layer located on the outer side of the sub-cavity and the thickness of the layer located on the inner side of the sub-cavity remain constant within the circumferential range of the sub-cavity.

3. The catheter device according to claim 1, characterized in that, The outer arc-shaped edge of the secondary cavity is not concentric with the inner arc-shaped edge of the secondary cavity.

4. The catheter device according to claim 1, characterized in that, The length of the arc-shaped side on the outer side of the secondary cavity is approximately equal to the length of the arc-shaped side on the inner side of the secondary cavity.

5. The catheter device according to claim 1, characterized in that, The end of the secondary cavity includes a shape composed of a combination of arcs and straight lines.

6. The catheter device according to claim 5, characterized in that, The extension of the straight line at the end of the secondary lumen does not pass through the axis of the catheter shaft.

7. The catheter device according to claim 5 or 6, characterized in that, When viewed from the midpoint of the secondary lumen, the intersection of the extension of the straight line at one end of the secondary lumen and the extension of the straight line at the other end of the secondary lumen is located further than the center of the catheter axis.

8. The catheter device according to claim 1, characterized in that, When a reference line is drawn from the midpoint of the circumference of the secondary cavity to connect with the inner arc-shaped edge, the two ends of the secondary cavity are located inside the reference line.

9. The catheter device according to claim 1, characterized in that, A reinforcing layer is provided on the outer side of the main cavity. No reinforcing layer is provided on the outside of the secondary cavity.

10. The catheter device according to claim 1, characterized in that, The outer layer has ribs that protrude from one of the arc-shaped edges on the outer side and the inner side of the sub-cavity toward the other.

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