Transcatheter device for treating tricuspid regurgitation

Abstract

The present invention provides a transcatheter device that can suppress the lifting phenomenon, which can cause impact to the pulmonary artery during heartbeats. [Solution] The transcatheter device according to the present invention includes a main shaft comprising an anchor fixed to the inner wall of the inferior vena cava, a proximal shaft extending from the anchor toward the tricuspid valve along the inferior vena cava-tricuspid valve isthmus of the heart, an intermediate shaft extending from the proximal shaft and passing through the tricuspid valve, to which a spacer that prevents regurgitation in the tricuspid valve is attached, and a distal shaft extending from the intermediate shaft into the pulmonary artery, wherein the distal shaft of the main shaft includes a first distal portion extending from the intermediate shaft in a curved shape having a predetermined curvature, a second distal portion extending from the first distal portion and bent toward the proximal shaft from a point B1 which is a point where it wraps around and crosses the aorta, and a third distal portion extending from the second distal portion toward the proximal shaft.

Description

Technical Field

[0001] The present invention relates to a transcatheter device for treating tricuspid regurgitation.

Background Art

[0002] Regurgitation of the tricuspid valve (TV) in the heart is a phenomenon in which blood leaks from the right ventricle (RV) to the right atrium (RA) through the tricuspid valve when the right ventricle (RV) contracts. This occurs when the tricuspid valve cannot be properly closed when the right ventricle (RV) contracts.

[0003] In recent years, as a method for treating tricuspid regurgitation, placing a transcatheter device in the regurgitation orifice (hereinafter referred to as the "regurgitation orifice") where the tricuspid valve cannot be closed has been utilized. Patent Document 1 was filed by the present applicant. The transcatheter device disclosed in Patent Document 1 includes an anchor that adheres to the inner wall of the inferior vena cava (IVC) and a main shaft that extends from the anchor and has a distal shaft at the tip locked to the pulmonary artery (PA). A spacer having a predetermined volume disposed in the regurgitation orifice of the tricuspid valve is attached to the main shaft.

[0004] The transcatheter device disclosed in Patent Document 1 is formed in a curved shape with a predetermined radius for an intermediate shaft with a spacer attached and a distal shaft that extends to and is locked to the pulmonary artery. As a result, there is a possibility that the distal shaft may be lifted and hit the inner wall of the pulmonary artery during a heartbeat, that is, a lifting phenomenon may occur. Such a lifting phenomenon can cause a problem of applying an impact to the pulmonary artery. Particularly when the transcatheter device is semi-permanently implanted, there may be a problem that the impact on the pulmonary artery due to the lifting phenomenon may occur continuously.

Prior Art Documents

[0005] [Patent Document 1] International release WO2024 / 080742 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The present invention aims to solve the problems of the prior art described above and to provide a transcatheter device that can suppress the lifting phenomenon that can apply impact to the pulmonary artery during heartbeat. [Means for solving the problem]

[0007] To achieve the above objective, the transcatheter device according to the present invention includes a main shaft comprising: an anchor fixed to the inner wall of the inferior vena cava (IVC); a proximal shaft extending from the anchor along the inferior vena cava-tricuspid isthmus (CTI) of the heart toward the tricuspid valve TV; a middle shaft extending from the proximal shaft and passing through the tricuspid valve TV, fitted with a spacer to prevent regurgitation in the tricuspid valve TV; and a distal shaft extending from the middle shaft into the pulmonary artery (PA). The distal shaft of the main shaft includes a first distal portion extending from the middle shaft in a curved shape having a predetermined curvature; a second distal portion extending from the first distal portion and bent toward the proximal shaft from point B1, which is a point where the shaft wraps around and crosses the aorta; and a third distal portion extending from the second distal portion toward the proximal shaft.

[0008] In a transcatheter device with this configuration, the distal shaft extends from point B1, the point where it crosses over the aorta, towards the proximal shaft. As a result, the distal shaft is further away from the upper wall of the pulmonary artery (PA) compared to conventional devices. Consequently, even when the distal shaft is lifted during heartbeats, it does not strike the upper wall of the pulmonary artery (PA), thus preventing the distal shaft from impacting the inner wall of the pulmonary artery (PA). [Effects of the Invention]

[0009] The transcatheter device according to the present invention can suppress the lifting phenomenon that applies impact to the pulmonary artery during cardiac beating. [Brief explanation of the drawing]

[0010] [Figure 1] This is a drawing showing a transcatheter device according to an embodiment of the present invention. [Figure 2] This is a magnified view of the distal shaft portion of a transcatheter device according to an embodiment of the present invention. [Figure 3] This drawing shows the internal structure of the spacer in a transcatheter device according to an embodiment of the present invention. [Figure 4] This is a drawing showing a transcatheter device according to an embodiment of the present invention in a state where it is seated in the heart. [Figure 5] Figure 5(a) is a cross-sectional view taken along the AA line in Figure 1, Figure 5(b) is a cross-sectional view taken along the BB line in Figure 1, and Figure 5(c) is a cross-sectional view taken along the CC line in Figure 1. [Figure 6] This diagram illustrates the lifting phenomenon that occurs with conventional transcatheter devices. [Figure 7] This diagram illustrates the lifting suppression effect of a transcatheter device according to an embodiment of the present invention. [Figure 8] This is a cross-sectional view showing a modified example of an anchor in a transcatheter device according to an embodiment of the present invention. [Figure 9] This drawing shows a modified example of the injection valve in a transcatheter device according to an embodiment of the present invention. [Figure 10] This is a drawing showing a marker provided on a transcatheter device according to an embodiment of the present invention. [Figure 11] This drawing shows a transcatheter device according to another embodiment of the present invention. [Figure 12] This is a drawing showing a transcatheter device according to yet another embodiment of the present invention. [Figure 13] This is a drawing showing a transcatheter device according to yet another embodiment of the present invention. [Modes for carrying out the invention]

[0011] To facilitate understanding of the present invention, embodiments in which the invention may be embodied will be described with reference to the accompanying drawings. The drawings in this specification are enlarged or some components omitted for the sake of explanation. In the following description, the area farther away from the practitioner will be referred to as "distal," and the area near will be referred to as "proximal." Also, with reference to Figures 1 and 2, the upper side will be referred to as "up," the lower side as "down," the left side as "left," and the right side as "right." Furthermore, the direction in which the main shaft and core wire, which will be described later, extend will be referred to as the "extension direction." In the description of the present invention, "bending" includes not only a sharp bend at a single point, but also a curved bend with a certain curvature around a single point.

[0012] Figures 1 to 3 are diagrams showing the transcatheter device 10 of this embodiment. Figure 1 shows the main shaft 100 as the center, Figure 2 shows a magnified view of the distal shaft 130 of the main shaft 100, and Figure 3 shows the spacer 300 as the center. Figure 4 is a diagram showing the transcatheter device 10 of this embodiment seated diagonally across the tricuspid valve TV.

[0013] Referring to FIGS. 1 to 4, the transcatheter device 10 of the present embodiment includes a spacer 300 disposed in the regurgitation space of the tricuspid valve TV to prevent regurgitation, a main shaft 100 for positioning and maintaining the spacer 300 so as to pass through the tricuspid valve TV between the inferior vena cava IVC and the pulmonary artery PA, and an anchor 200 for fixing the proximal end portion of the main shaft 100 to the inner wall of the inferior vena cava IVC.

[0014] The main shaft 100 is formed of a proximal shaft 110, an intermediate shaft 120, and a distal shaft 130 that extend longitudinally from the proximal side to the distal side. A core wire 103 described later is inserted into the main shaft 100. The core wire 103 maintains the basic rigidity and elasticity of the main shaft 100. In the following description, the points, lengths, angles, etc. used to describe each part of the main shaft 100 are based on the core wire 103.

[0015] The proximal shaft 110 of the main shaft 100 is disposed adjacent to the inferior vena cava IVC as shown in FIG. 4, and is also disposed adjacent to the isthmus CTI between the inferior vena cava IVC and the tricuspid valve TV. The proximal shaft 110 has a substantially vertically inverted L shape, that is, an "inverted L" shape, which extends generally vertically along the shapes of the inferior vena cava IVC and the isthmus CTI and then extends generally horizontally. On the other hand, such a shape of the proximal shaft 100 can be deformed into various forms according to the structure and size of the isthmus CTI of the patient's heart.

[0016] As shown in FIGS. 1 and 4, the proximal shaft 110 in this embodiment extends from the anchor 200 fixed to the inferior vena cava IVC (from the point M0 connected to the anchor 200) to the upper side (heart side) to the point M1, and the first proximal portion 111, the first bending portion 112 that is bent from the first proximal portion 111 (the point M1 connected to the first proximal portion 111) to the right side toward the tricuspid valve TV to the point M2, and the second proximal portion 113 that extends from the first bending portion 112 (the point M2 connected to the first bending portion 112) to the right side toward the tricuspid valve TV to the point M3, and the second bending portion 114 that is bent from the second proximal portion 113 (the point M3 connected to the second proximal portion 113) to the upper side and is connected to the intermediate shaft 120 at the point M4. Further, a link (510) for connecting the transcatheter device 10 and a deployment catheter (not shown) may be provided at the lower part of the proximal shaft 110.

[0017] The first proximal portion 111 and the second proximal portion 113 of the proximal shaft 110 have a linear form. However, since the specific shape of the heart varies among patients, the first proximal portion 111 and the second proximal portion 113 of the proximal shaft 110 that extend along the shape of the inferior vena cava IVC and the isthmus CTI can have various shapes along the specific shape of the heart. For example, the first proximal portion 111 and the second proximal portion 113 of the proximal shaft 110 may extend in a curved shape, or may extend in a shape combined with a straight line and a curve.

[0018] In this embodiment, the length L1 of the first proximal portion 111 in the extension direction (length from point M0 to point M1) is approximately in the range of 20 mm to 75 mm, and the length L2 of the second proximal portion 113 in the extension direction (length from point M2 to point M3) is approximately in the range of 10 mm to 85 mm. The interior angle α1 of the first bent portion 112 (the angle between the tangent at point M1 and the tangent at point M2) is approximately in the range of 60° to 140°, and the interior angle α2 of the second bent portion 114 (the angle between the tangent at point M3 and the tangent at point M4) is approximately in the range of 60° to 140°. The "length in the extension direction" described here refers to the length extending along the extension direction of the main shaft 100 (more specifically, the core wire 103), and in the case of a curve, it refers to the length along the shape of the curve. The same applies in the following description.

[0019] In particular, as shown in Figure 4, it is preferable to install the anchor 200 so that the main shaft 100 is stably and firmly fixed overall, with the first proximal portion 111 extending along the longitudinal direction of the inferior vena cava IVC while being in maximum contact with the inner wall of the inferior vena cava IVC, and the second proximal portion 113 extending along the isthmus CTI.

[0020] Next, the intermediate shaft 120 extends upward toward the pulmonary artery PA from point M4, where it connects with the second bent portion 114 of the proximal shaft 110, and is positioned to pass across the tricuspid valve TV, as shown in Figure 4.

[0021] The length L3 of the intermediate shaft 120 in the extension direction (specifically, the length from point M4 where it connects to the proximal shaft 110 to point M5 where it connects to the distal shaft 130) is approximately in the range of 40 mm to 160 mm. In this embodiment, the intermediate shaft 120 extends in a straight line, but is not limited to this. The intermediate shaft 120 can be transformed into various shapes depending on the structure and size of the patient's heart. For example, the intermediate shaft 120 may extend in a curved shape, or in a shape that combines straight lines and curves.

[0022] As mentioned above, a spacer 300 is attached to the intermediate shaft 120. The spacer 300 attached to the intermediate shaft 120 is positioned in the backflow space of the tricuspid valve TV, whose end is connected to the tricuspid round (TVA), as shown in Figure 4.

[0023] Next, as shown in Figure 4, the distal shaft 130 extends along the pulmonary artery PA from the distal end of the intermediate shaft 120 to the inside of the pulmonary artery PA. As shown in Figures 1 and 2, the distal shaft 130 consists of a first distal section 131 that extends in a curve from point M5, which is connected to the intermediate shaft 120, to point M6; a second distal section 132 that extends from the first distal section 131 (point M6) and is bent from point B1 toward the proximal shaft 110 to point M7; and a third distal section 133 that extends from the second distal section 132 (point M7) toward the distal end of the distal shaft 130 toward the proximal shaft 110. Here, "bent toward the proximal shaft 110" means that when an extension line is drawn from point B1 as the center at a proximal point where the bending has not yet begun, the shaft bends toward the proximal shaft 110 more toward the proximal shaft 110 than the direction of extension of that line.

[0024] When the distal shaft 130 is attached to the heart, it is preferable that the first distal portion 131 to the third distal portion 133 are designed to conform to the shape of the pulmonary artery PA without the distal shaft 130 colliding with the inner wall of the pulmonary artery PA, as shown in Figure 4. On the other hand, the pulmonary artery PA has a shape that curves while enveloping the aorta at the portion that connects to the heart.

[0025] In this embodiment, the first distal portion 131, as shown in Figures 1 and 2, is the portion between point M5, which is connected to the intermediate shaft 120, and point M6, which is connected to the second distal portion 132, and can consist of multiple curves having different curvatures. Point M6, as shown in Figure 4, is the position that wraps around and crosses over the aorta.

[0026] The position of point M6 in the first distal section 131 varies depending on the morphology and size of the patient's pulmonary artery PA and heart, but the horizontal length H1 between points M5 and M6 is approximately in the range of 20 mm to 40 mm, and the vertical length V1 between points M5 and M6 is approximately in the range of 20 mm to 50 mm. In addition, the extensional length L4 of the first distal section 131 (extensional length from point M5 to point M6) is approximately in the range of 40 mm to 110 mm. The internal angle α3 of the first distal section 131 (the angle between the tangent at point M5 and the tangent at point M6) is approximately in the range of 80° to 120°. In this embodiment, the internal angle α3 of the first distal section 131 is approximately 90°. Having such a range, the first distal section 131 extends to a position where it encloses and crosses over the aorta.

[0027] Furthermore, the second distal section 132 is the portion between point M6, which connects to the first distal section 131, and point M7, which connects to the third distal section 133, and is bent in a direction toward the proximal shaft 110 from point B1, which is a point in the second distal section 132. In this embodiment, point B1, which is the bending point of the second distal section 132, is a point distal to point M6, which connects to the first distal section 131. That is, in the distal shaft 130 of this embodiment, as shown in Figure 4, point M6 is positioned to wrap around and cross over the aorta, and point B1, which is the bending point, is positioned distal to point M6, so that it is bent in a direction toward the proximal shaft 110 from the point that wraps around and crosses over the aorta.

[0028] When the section between point M6 and point B1 of the second distal section 132 is formed in a curved shape, and the section between point B1 and point M7 of the second distal section 132 is also formed in a curved shape, and the second distal section 132 is formed in a curved shape overall, the interior angle α4 of the second distal section 132 (the angle between the tangent at point M6 and the tangent at point M7) is in the range of approximately 90° to 130°. In this embodiment, the interior angle α4 of the second distal section 132 is approximately 120°.

[0029] Furthermore, the horizontal length H2 between point B1 and point M5, which are the bending points in the second distal section 132, is approximately in the range of 30 mm to 50 mm, and the extensional length L7 from point M5 to point B1 is in the range of 55 mm to 65 mm. Also, the extensional length L5 of the second distal section 132 (extensional length from point M6 to point M7) is approximately in the range of 10 mm to 50 mm. These dimensional ranges may vary depending on the morphology and size of the patient's pulmonary artery PA and heart.

[0030] In this embodiment, the section between point M6 and point B1 of the second distal section 132 is formed in a curved shape, but it may be formed in a straight line depending on the morphology and size of the patient's pulmonary artery PA and heart. Also, in this embodiment, the section between point B1 and point M7 of the second distal section 132 is formed in a straight line, but it may be formed in a curved shape depending on the morphology and size of the patient's pulmonary artery PA and heart.

[0031] Furthermore, in this embodiment, it is preferable that the approximate radius of curvature R2 at point B1, which is the bending point of the second distal portion 132, is smaller than the approximate radius of curvature R1 of the first distal portion 131. Here, "approximate radius of curvature" means the radius of curvature of the approximate curve that is drawn to be closest to the curves formed by multiple curves or by a combination of curves and straight lines forming a continuous structure. For example, the approximate curve may be a curve drawn by the already known least squares method. Depending on the morphology and size of the patient's pulmonary artery PA and heart, the approximate radius of curvature R2 at point B1, which is the bending point of the second distal portion 132, is in the range of approximately 13 mm to 17 mm, and the approximate radius of curvature R1 of the first distal portion 131 is in the range of approximately 27 mm to 33 mm.

[0032] In the transcatheter device 10 of this embodiment, the distal shaft 130 is bent from point B1, which is distal to point M6 where it crosses over the aorta, toward the proximal shaft 110. Therefore, when the distal shaft 130 is positioned within the pulmonary artery PA, it is located away from the upper wall of the pulmonary artery PA, and even if the distal shaft 130 is lifted during a heartbeat, it does not strike the upper wall of the pulmonary artery PA (see Figures 7(a) and 7(b)). Thus, the transcatheter device 10 of this embodiment can suppress lifting that may occur during a heartbeat.

[0033] Furthermore, in the transcatheter device 10 of this embodiment, the approximate radius of curvature R2 of the second distal portion 132 is smaller than the approximate radius of curvature R1 of the first distal portion 131. Therefore, when the distal shaft 130 is inserted into the pulmonary artery PA, the distal shaft 130 is positioned more reliably away from the upper wall of the pulmonary artery PA, and even if the distal shaft 130 is lifted during heartbeat, it will not hit the upper wall of the pulmonary artery PA (see Figures 7(a) and 7(b)). Thus, the transcatheter device 10 of this embodiment can more reliably suppress lifting that may occur during heartbeat.

[0034] Furthermore, the third distal portion 133 extends from point M7, where it connects with the second distal portion 132, toward the proximal shaft 110, and may be formed linearly depending on the morphology and size of the patient's pulmonary artery PA and heart. Preferably, the third distal portion 133 extends along the shape of the pulmonary artery PA so as not to contact the inner wall of the pulmonary artery PA.

[0035] Furthermore, the third distal portion 133 may have at least one section with a curved shape depending on the morphology and size of the patient's pulmonary artery PA and heart. However, this curve does not deviate significantly from a straight shape. The end of the third distal portion 133 may bend in the direction of length extension. The range of bending may be approximately 140° to 200°. If the end of the third distal portion 133 bends beyond 180°, the end of the third distal portion 133 may move away from the proximal shaft 110, but care is taken to prevent a lifting phenomenon from occurring. Also, the length L6 of the third distal portion 133 in the direction of extension is approximately 40 mm to 120 mm.

[0036] Referring to the cross-section of the main shaft 100 shown in Figure 5, the main shaft 100 is made of a jacket 101 composed of pellethane having a predetermined hardness. Pellethane is a brand name for thermoplastic polyurethane elastomer, mainly used in medical devices.

[0037] The hardness of the pelletane constituting the jacket 101 of the proximal shaft 110, intermediate shaft 120, and distal shaft 130 of the main shaft 100 can be varied. In particular, for the distal shaft 130, the hardness of the pelletane constituting the jacket 101 can be varied as it approaches the distal side. For example, the hardness can be made to decrease as it approaches the distal side of the distal shaft 130, so that it can be easily deformed to conform to the shape of the pulmonary artery PA. In addition, the end of the third distal portion 133 of the distal shaft 130 can be covered with an e-PTFE layer. The e-PTFE layer is a polymer, and is polytetrafluoroethylene (PTFE).

[0038] Furthermore, a guidewire lumen 102 is formed within the jacket 101 of the main shaft 100, through which the guidewire passes, in order to guide and direct the transcatheter device 10 during the procedure over its entire length (see Figures 5(a), (b), and (c)).

[0039] The core wire 103 is inserted into the jacket 101 up to a predetermined portion of the main shaft 100, specifically the proximal shaft 110, the intermediate shaft 120, and the distal shaft 130 (specifically, the intermediate portion of the third distal section 133) (see Figures 5(b) and (c)). The core wire 103 can be made of a nitinol alloy or the like with predetermined rigidity. The core wire 103 maintains the overall annular shape of the main shaft 100 and can generate elasticity that causes it to return to its original shape if deformed by an external force.

[0040] Furthermore, an injection tube lumen 104 is formed to guide the injection tube 410 to a predetermined location near the proximal shaft 110 and the intermediate shaft 120 of the main shaft 100 (specifically, to the injection hole 106 described later) (see Figure 5(c)).

[0041] Referring again to Figures 1 and 2, the anchor 200 connected to the proximal shaft 110 of the main shaft 100 consists of a spiral coil made by winding a metal wire. The anchor 200 expands to adhere closely to the inner wall of the inferior vena cava IVC. The position of the proximal shaft 110 of the transcatheter device 10 in this embodiment is fixed by the anchor 200 adhering closely to and fixing to the inner wall of the inferior vena cava IVC.

[0042] It is preferable that the anchor 200 is fixed to the inner wall of the inferior vena cava (IVC) so that it does not move by being pulled toward the heart even when the heart moves during a heartbeat. For this purpose, as shown in Figure 1 in this embodiment, the outer surface of the anchor 200 can be provided with a plurality of projections 210 that contact the inner wall of the inferior vena cava (IVC) while fixed to the inner wall of the inferior vena cava (IVC) and protrude outward. Such projections 210 can increase friction with the inner wall of the inferior vena cava (IVC) and maintain more stable fixation of the anchor 200.

[0043] Referring to Figure 3, a spacer 300 is provided on the intermediate shaft 120. The spacer 300 encloses the intermediate shaft 120 and is provided over a range from one point on the second proximal portion 113 of the proximal shaft 110 to one point on the first distal portion 131 of the distal shaft 130.

[0044] The spacer 300 comprises a mesh structure 310 that encloses the main shaft 100, and a balloon 320 that encloses the mesh structure 310, maintaining a sealed internal space, and whose size is adjusted by the amount of liquid (saline solution) injected into the internal space.

[0045] The mesh structure 310 is made by forming a mesh of wires made of shape memory alloy or the like, and maintains a shape with a predetermined volume when no external force is applied. The mesh structure 310 can also contract when an external force is applied. One of the proximal and distal ends of the mesh structure 310 is fixed to the main shaft 100, while the other end is not fixed to the main shaft 100 and can move along the longitudinal direction. Therefore, when the mesh structure 310 contracts or expands, the other end, which is not fixed to the main shaft 100, moves along the main shaft 100.

[0046] The balloon 320 can be deflated or expanded by the saline solution S filling its internal space, and both ends are fixed to the main shaft 100. An injection hole 106 is formed in the main shaft 100 to supply the saline solution S into the balloon 320. Referring to the enlarged portion of Figure 3, the injection hole 106 is located inside the balloon 320 and communicates with an injection tube lumen 104 formed in the jacket 101 of the main shaft 100.

[0047] Furthermore, an injection valve 400 is provided on the outside of the injection hole 106 to open and close communication with the injection hole 106. The injection valve 400 is a silicone band 420 that surrounds the injection hole 106. The injection tube 410 is inserted from the outside through the injection tube lumen 104, passes through the injection hole 106, and protrudes into the internal space of the balloon 320. The silicone band 420 is then expanded by the injection tube 410.

[0048] In this state, the mesh structure 310 is not fully inflated by the contracted balloon 320, but it maintains a predetermined space inside. Therefore, the injection tube 410 can protrude into the internal space of the balloon 320. Subsequently, when saline solution S is injected into the internal space of the balloon 320 through the injection tube 410, the balloon 320 expands. Along with this, the mesh structure 310 also expands into its stored shape.

[0049] After the balloon 320 has inflated to the desired volume, when the injection tube 410 is retrieved externally through the injection hole 106, the silicone band 420 contracts and closes the injection hole 106. This prevents the injected saline solution S from escaping from the balloon 320, and the balloon 320 maintains its shape with the predetermined volume.

[0050] The volume of the spacer 300 having this configuration can be adjusted by the amount of saline solution S injected into the balloon 320. Therefore, the size of the spacer 300 can be adjusted to match the size of the regurgitation space where tricuspid valve regurgitation occurs. As a result, if the spacer 300 does not match the size of the regurgitation space during the procedure, the practitioner only needs to adjust the amount of saline solution S injected without needing to retrieve it. In addition, the inside of the balloon 320 may be filled with a substance other than saline solution S (e.g., contrast agent, gel, fiber, etc.).

[0051] As shown in Figure 4, the transcatheter device 10 according to this embodiment, having the configuration described above, is positioned in the heart with the anchor 200 fixed in the inferior vena cava (IVC) and the distal shaft 130 straddling the pulmonary artery (PA). At this time, the spacer 300 passes through the regurgitation space of the tricuspid valve (TV). When saline solution is supplied to the spacer 300 in this state to inflate the balloon 320 to the desired volume, the balloon 320 fills the regurgitation space of the tricuspid valve (TV).

[0052] In this embodiment, the transcatheter device 10, when positioned as described, has the main shaft 100 tilted in direction A in Figure 4, causing the first bent portion 112 and the second bent portion 114 of the proximal shaft 110 to be subjected to force in direction A. Furthermore, because the main shaft 100 is elastic, an elastic force acts from the first bent portion 112 and the second bent portion 114 of the proximal shaft 110 in direction B, and this elastic force in direction B causes the main shaft 100 to contact the supraventricular ridge (SC) in direction B. In other words, the elastic force of the main shaft 100 in direction B maintains the desired position of the spacer 300 attached to the main shaft 100.

[0053] On the other hand, when a conventional transcatheter device 90, in which the distal shaft 930 is formed by a curve with a certain curvature, is placed in the heart, the distal shaft 930 is positioned so as not to contact the inner wall of the pulmonary artery PA, as shown in Figure 6(a). However, when the heart moves in the direction of the arrow (4 o'clock to 5 o'clock direction) during a heartbeat, as shown in Figure 6(b), the portion of the main shaft 900 that contacts the supraventricular ridge (SC) is lifted up (specifically, the portion shown as an ellipse) on the right side of the diagram and strikes the upper wall of the pulmonary artery PA. Because the heart moves back and forth in the direction of the arrow during a heartbeat, the distal shaft 930 repeatedly strikes the upper wall of the pulmonary artery PA, causing a lifting phenomenon that impacts the pulmonary artery PA.

[0054] In contrast, in the transcatheter device 10 according to this embodiment, the second distal portion 132 is bent in a direction toward the proximal shaft 110 from point B1 (a point where it wraps around and crosses over the aorta), which is the bending point. As a result, in the transcatheter device 10 according to this embodiment, as shown in Figure 7(a), the portion of the distal shaft 130 from point B1 to the distal end is further away from the upper wall of the pulmonary artery PA compared to conventional transcatheter devices. Consequently, when the heart beats, it moves in the direction of the arrow (4 o'clock to 5 o'clock direction), and as shown in Figure 7(b), even when the distal shaft 130 is lifted, it does not hit the upper wall of the pulmonary artery PA, thereby preventing the distal shaft 130 from impacting the inner wall of the pulmonary artery PA.

[0055] Furthermore, in the transcatheter device 10 according to the embodiment of the present invention, the approximate radius of curvature R2 at point B, which is the bending point of the second distal portion 132, is smaller than the approximate radius of curvature R1 of the first distal portion 131. As a result, even though the second distal portion 132 is formed in a curve at point B1, the portion of the distal shaft 130 from point B1 to the distal end is reliably further away from the upper wall of the pulmonary artery PA compared to conventional devices. Consequently, even when the distal shaft 130 is lifted during cardiac beating, as shown in Figure 7(b), it does not hit the upper wall of the pulmonary artery PA, thereby preventing the distal shaft 130 from impacting the inner wall of the pulmonary artery PA.

[0056] Furthermore, in the transcatheter device 10 according to the embodiment of the present invention, the internal angle α3 of the first distal portion 131 (the angle between the tangent at point M5 and the tangent at point M6) is formed in the range of 80° to 120°. As a result, point M6 is positioned over the aorta while enveloping it, and this ensures that point B1, which is located distal to point M6, is reliably positioned at a single point over the aorta while enveloping it.

[0057] Furthermore, in the transcatheter device 10 according to the embodiment of the present invention, the internal angle α4 of the second distal portion 132 (the angle between the tangent at point M6 and the tangent at point M7) is formed in the range of 90° to 130°, so that the portion of the distal shaft 130 from point B1 to the distal end is reliably further away from the upper wall of the pulmonary artery PA compared to conventional devices.

[0058] As described in detail above, the transcatheter device 10 according to this embodiment can prevent the lifting phenomenon from occurring, in which the distal shaft 130 impacts the inner wall of the pulmonary artery PA during heartbeat. As a result, the transcatheter device 10 according to this embodiment can be placed in the heart semi-permanently.

[0059] <Variation>

[0060] The following describes modifications of the main components of the catheter device 10 according to this embodiment. Figure 8 is a cross-sectional view showing a modified anchor in the transcatheter device according to the embodiment of the present invention. As mentioned above, the anchor 200 is for fixing the proximal side of the transcatheter device 10 to the inferior vena cava IVC. In this embodiment, a plurality of protrusions 210 are provided on the anchor 200 to increase the frictional force with the inner wall of the inferior vena cava IVC.

[0061] As shown in Figure 8(a), the projection 210 can have a cross-sectional shape that protrudes toward the heart. In this case, if the anchor 200 is subjected to a force pulling toward the heart during heartbeat, it can be prevented from being pulled toward the heart and moving. Furthermore, the projection 210 in this modified example is designed not to protrude toward the opposite side of the heart. This allows the anchor 200 to be easily removed outward (downward) when the transcatheter device 10 is retrieved from the body.

[0062] Furthermore, as shown in Figure 8(b), instead of the projection 210, the outer surface of the anchor 200 can have irregularities 220 that contact the inner wall of the inferior vena cava IVC while anchored to it. When the irregularities 200 also contact the inferior vena cava IVC, the frictional force with the inner wall of the inferior vena cava IVC can be increased, thereby stabilizing the anchoring of the anchor 200.

[0063] Figure 9 is a diagram showing a modified injection valve in a transcatheter device according to an embodiment of the present invention. As described above, the injection valve 400 opens and closes the injection hole 106 through which the injection tube 410 for injecting saline solution S passes. On the other hand, the injection tube 410 shown in Figure 3 protrudes inside the balloon 320 when saline solution S is injected, which may damage the balloon 320 if it comes into contact with it. If the balloon 320 is damaged, the saline solution S may leak out of the balloon 320, preventing the transcatheter device 10 from performing its function.

[0064] In this modified example, as shown in Figure 9(a), an incision 421 is formed on the distal side of the silicone band 420, creating a gap between the silicone band 420 and the main shaft 100. Furthermore, the injection tube 410 is located inside the silicone band 420 and does not protrude outside it. In this modified example, even though the injection tube 410 is located inside the silicone band 420, saline solution S can be injected into the internal space of the balloon 320 through the gap. Additionally, because the injection tube 410 is located inside the silicone band 420 in this modified example, damage to the balloon 320 by the injection tube 410 can be prevented.

[0065] Furthermore, as shown in Figure 9(b), a protective cover 422 made of pelletane can be wrapped around the outside of the injection tube 410 that protrudes from the outside of the silicone band 420, so that even if the protective cover 422 comes into contact with the balloon 320, it will not damage the balloon 320. In this modified example, the protective cover 422 is fixed to the main shaft 100 (specifically, the intermediate shaft 120).

[0066] The modified example in Figure 10 includes markers placed on the transcatheter device 10 to clearly identify its position during the procedure. Examples of markers include marker 611 located at the distal end of the distal shaft 130, marker 612 located at the tip of the core wire 103 as the middle part of the second distal section 132 of the distal shaft 130, marker 613 provided near the distal end of the spacer 300, and marker 614 provided on the first bent section 112 of the proximal shaft 110.

[0067] Here, markers 611, 612, and 613 may be band-type markers, and marker 614 may be a strip-type marker. Through each marker, the operator can easily understand the position of the configuration in which the marker is located on the transcatheter device 10, thereby allowing the transcatheter device 10 to be positioned more accurately to the desired location.

[0068] <Other Embodiments>

[0069] Figure 11 is a drawing showing transcatheter devices 10a and 10b according to other embodiments of the present invention. Transcatheter devices 10a and 10b differ from the transcatheter device 10 shown in Figure 1 in the shape of the first proximal portion 111 of the proximal shaft 110.

[0070] As mentioned above, the first proximal portion 111 of the proximal shaft 110 may be formed along the shape of the inferior vena cava (IVC), and may be formed in a curved shape, for example, as shown in Figures 11(a) and 11(b). In Figure 11(a), the center of the radius of curvature R3 is located on the right side of the first proximal portion 111, and in Figure 11(b), the center of the radius of curvature R3 may be located on the left side of the first proximal portion 111.

[0071] Figure 11 shows that in the transcatheter devices 10a and 10b according to other embodiments of the present invention, the first proximal portion 111 may be formed as a single curve, or as a shape combining multiple curves or curves and straight lines. In the transcatheter devices 10a and 10b according to other embodiments of the present invention, the approximate radius of curvature R3 of the first proximal portion 111 (from point M0 to point M1) may be in the range of approximately 90 mm to 110 mm.

[0072] Figure 12 is a drawing showing transcatheter devices 10c and 10d according to yet another embodiment of the present invention. Transcatheter devices 10c and 10d differ from the transcatheter device 10 shown in Figure 1 in the shape of the second proximal portion 113 of the proximal shaft 110.

[0073] As described above, the second proximal portion 113 of the proximal shaft 110 may be formed along the shape of the isthmus CTI between the inferior vena cava IVC and the tricuspid valve TV, and may be formed in a curved shape as shown in Figures 12(a) and 12(b). In Figure 12(a), the center of the radius of curvature R4 is located on the lower side of the second proximal portion 113, and in Figure 12(b), the center of the radius of curvature R4 may be located on the upper side of the second proximal portion 113.

[0074] In the transcatheter devices 10c and 10d according to yet another embodiment of the present invention shown in Figure 12, the second proximal portion 113 may be formed as a single curve, or as a combination of multiple curves or curves and straight lines. In the transcatheter devices 10c and 10d according to yet another embodiment of the present invention, the approximate radius of curvature R4 of the second proximal portion 113 (from point M2 to point M3) may be in the range of approximately 90 mm to 110 mm.

[0075] Figure 13 is a drawing showing a transcatheter device 10e according to yet another embodiment of the present invention. Referring to Figure 13, the intermediate shaft 120 of the transcatheter device 10e according to yet another embodiment of the present invention is formed in a curved shape from point M4, which is connected to the second bent portion 114 of the proximal shaft 110, to point M5, which is connected to the first distal portion 131 of the distal shaft 130. The shape of this curve has its center of curvature on the left side (right atrium (RA) side), and the radius of curvature R5 of the intermediate shaft 120 (from point M4 to point M5) is in the range of approximately 135 mm to 165 mm. Furthermore, it is preferable that the shape of the curve of the intermediate shaft 120 smoothly connects with the shape of the curve of the first distal portion 131 of the distal shaft 130 and the shape of the curve of the second bent portion 114 of the proximal shaft 110.

[0076] The embodiments and modifications of the present invention described above are intended to facilitate understanding of the spirit of the present invention as described in the claims. Therefore, the present invention is not limited to these embodiments and modifications and can be modified in various ways within the scope described in the claims. For example, the present invention may have a main shaft made up of various combinations of proximal shafts and intermediate shafts disclosed in the embodiments disclosed in Figures 11 to 13. [Explanation of symbols]

[0077] 10, 10a, 10b, 10c, 10d, 10e: Transcatheter devices 100: Main shaft 101: Jacket 102: Guide wire lumen 103: Core wire 104: Injection tube lumen 106: Injection Hole 110: Proximal shaft 111: First proximal part 112: First folding section 113: Second proximal part 114: Second folding section 120: Intermediate shaft 130: Distal shaft 131: First distal part 132: Second distal part 133: Third distal part 200: Anchor 210: Protrusion 220: Unevenness 300: Spacer 310: Mesh structure 320: Balloon 400: Injection valve 410: Injection tube 420: Silicone band 421: Incision site 422: Protective cover 510: Link 611, 612, 513, 614: Markers IVC: Inferior Vena Cava RV: right ventricle RA: right atrium PA: Pulmonary artery CTI: Isthmus between the inferior vena cava and the tricuspid valve TV: Tricuspid valve TVA: Mitsugimaru SC:Ryo Murokami

Claims

1. An anchor (200) that is fixed to the inner wall of the inferior vena cava (IVC), The main shaft (100) includes a proximal shaft (110) extending from the anchor (200) along the inferior vena cava-tricuspid isthmus (CTI) of the heart toward the tricuspid valve (TV), an intermediate shaft (120) extending from the proximal shaft (110) and passing through the tricuspid valve (TV), and fitted with a spacer (300) to prevent regurgitation in the tricuspid valve (TV), and a distal shaft (130) extending from the intermediate shaft (120) into the pulmonary artery (PA), The distal shaft (130) in the main shaft (100) is A first distal portion (131) extends from the intermediate shaft (120) in a curved shape having a predetermined curvature, A second distal portion (132) extends from the first distal portion (131) and is bent in a direction approaching the proximal shaft (110) from point B1, which is a point where the aorta is wrapped around and crossed over, A transcatheter device including a third distal portion (133) extending from the second distal portion (132) toward the proximal shaft (110).

2. The transcatheter device according to claim 1, wherein the approximate radius of curvature R2 at point B1, which is a bending point in the second distal portion (132), is smaller than the approximate radius of curvature R1 of the first distal portion (131).

3. The transcatheter device according to claim 1, wherein the internal angle α3 of the first distal portion (131) (the angle between the tangent at point M5 connected to the intermediate shaft (120) and the tangent at point M6 connected to the second distal portion (132)) is 80° to 120°.

4. The transcatheter device according to claim 1, wherein the internal angle α4 of the second distal portion (132) (the angle between the tangent at point M6 connected to the first distal portion (131) and the tangent at point M7 connected to the third distal portion (133)) is 90° to 130°.

5. The transcatheter device according to claim 1, wherein the third distal portion (133) has at least one section that curves on the proximal shaft (110) side.

6. The transcatheter device according to claim 1, wherein the intermediate shaft (120) has a curved shape.

7. The transcatheter device according to claim 1, wherein the intermediate shaft (120) is in a straight shape.

8. The proximal shaft (110) has a first proximal portion (111) extending from the anchor (200) along the inferior vena cava (IVC), a first bent portion (112) that is bent from the first proximal portion (111) toward the isthmus of the heart, a second proximal portion (113) that extends from the first bent portion (112) toward the tricuspid valve (TV) along the isthmus (CTI) of the heart, and a second bent portion (114) that is bent from the second proximal portion (113) and connected to the intermediate shaft (120). The transcatheter device according to claim 1, wherein at least one of the first proximal portion (111) and the second proximal portion (113) is in the shape of a curve.

9. The transcatheter device according to any one of claims 1 to 8, wherein the anchor (200) has the shape of a spiral coil and is fixed to the inner wall of the inferior vena cava (IVC) by expanding.

10. The transcatheter device according to claim 9, wherein the outer circumferential surface of the anchor (200) has a projection (210) that, while fixed to the inner wall of the inferior vena cava (IVC), contacts the inner wall of the inferior vena cava (IVC) and protrudes toward the heart.

11. The transcatheter device according to claim 9, wherein the outer surface of the anchor (200) has irregularities (220) that contact the inner wall of the inferior vena cava (IVC) while fixed to the inner wall of the inferior vena cava (IVC).

12. The aforementioned spacer (300) is A mesh structure (310) that can be contracted or expanded, and which expands to have a predetermined shape when no external force is applied from the surroundings, The transcatheter device according to claim 1, comprising a balloon (320) that covers and seals the mesh structure (310) and whose size is adjusted according to the amount of liquid injected into the internal space.

13. An injection tube lumen (104) for inserting an injection tube (410) is formed along the longitudinal direction inside the main shaft (100). The main shaft (100) has, An injection hole (106) that connects the internal space of the injection tube lumen (104) and the spacer (300), The transcatheter device according to claim 12, further comprising an injection valve (400) including a silicone band (420) that encloses the injection hole (106) and opens and closes the communication between the injection tube lumen (104) and the injection hole (106) when the injection tube (410) is inserted or removed.

14. The transcatheter device according to claim 13, wherein the injection tube (410) passes through the injection hole (106) and its tip protrudes into the internal space of the spacer (300), and the tip of the injection tube (410) is enclosed by a protective cover (422).

15. The transcatheter device according to claim 13, wherein the injection valve (410) has an incision (421) formed distal to the silicone band (420), and the injection tube (410) passes through the injection hole (106) with its tip positioned inside the silicone band (410).

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