A covered stent for intrahepatic portosystemic shunt with adaptively adjustable covering length

Abstract

The present invention relates to a covered stent for intrahepatic portal shunt capable of adaptively adjusting the length of the covering, comprising a tubular frame and a covering, wherein the covering comprises an upper self-curling segment of the covering, an intermediate fixed segment of the covering, and a lower self-curling segment of the covering which are connected in sequence, wherein the intermediate fixed segment of the covering is fixed on the tubular frame, and the upper self-curling segment of the covering and the lower self-curling segment of the covering are coated on the tubular frame, and the tubular frame is located below the covering to form a lower bare stent. After the covered stent of the present invention is placed, the covered stent is expanded by balloon dilation, and the self-curling segments of the covering at both ends naturally curl toward the middle, and stop curling when obstructed, so that the length of the covering is consistent with the liver parenchyma area, greatly reducing the adverse effects caused by the inconsistency between the covering length and the actual required length, and reducing the occurrence of complications.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and in particular relates to a covered stent for intrahepatic portosystemic shunt with adaptively adjustable covering length. Background Art

[0002] Transjugular intrahepatic portosystemic shunt (TIPS) creates a shunt between the portal vein and the hepatic vein in the liver parenchyma through a covered stent. With the advancement of technology, portosystemic shunts released by ultrasound endoscopy or percutaneous puncture are expected to appear. This type of intrahepatic portosystemic shunt can reduce portal vein pressure and can also be combined with esophageal and gastric vein embolization to completely treat gastrointestinal bleeding caused by portal hypertension in cirrhosis.

[0003] At present, the covered stents used for intrahepatic portosystemic shunt surgery mainly include self-expanding nickel-titanium alloy stents, which are covered with low-permeability polytetrafluoroethylene membrane (PTEF membrane). The covered stents are divided into intrahepatic covered area and portal vein bare area according to their functional areas. However, based on the existing covered stent structure and medical technology level, it is still impossible to accurately control the covered part of the covered stent to be completely located in the liver parenchyma (generally the covered part is larger than the liver parenchyma), resulting in the following problems: 1. Low shunt efficiency; 2. Easily form vortices and further form thrombi, causing stent occlusion.

[0004] In addition, after the existing covered stent is placed in the liver and set in position, it needs to be replaced with a balloon for expansion. This step is cumbersome and can easily cause the guidewire to fall off (after successful puncture, the guidewire is placed, the stent is replaced, and the balloon catheter is replaced for expansion, which requires at least three exchanges), affecting subsequent operations. Summary of the invention

[0005] In view of the problems pointed out in the above background technology, the present invention proposes a covered stent for intrahepatic portosystemic shunt with adaptively adjustable covering length.

[0006] The technical solution adopted by the present invention is:

[0007] A covered stent for intrahepatic portosystemic shunt with adaptively adjustable covering length comprises a tubular frame and a covering, wherein the covering comprises an upper self-curling segment of the covering, an intermediate fixed segment of the covering and a lower self-curling segment of the covering which are connected in sequence, the intermediate fixed segment of the covering is fixed on the tubular frame, the upper self-curling segment of the covering and the lower self-curling segment of the covering are coated on the tubular frame, and the tubular frame is located below the covering to constitute a lower bare stent.

[0008] Furthermore, the upper self-curling section of the coating, the middle fixed section of the coating and the lower self-curling section of the coating are made of polytetrafluoroethylene; the upper self-curling section of the coating and the lower self-curling section of the coating are embedded with memory metal wires that can be curled according to a set arc.

[0009] Furthermore, the length of the tubular skeleton is 10 cm, the length of the middle fixed section of the coating is 5 cm, the length of the upper self-curling section of the coating and the lower self-curling section of the coating are each 2 cm, and the length of the lower bare stent is 1 cm.

[0010] Furthermore, the tubular skeleton is a tubular structure woven from nickel-titanium wires.

[0011] Furthermore, the intrahepatic portosystemic shunt covered stent is covered with an outer sheath for protection.

[0012] Furthermore, the above-mentioned coated stent for intrahepatic portosystemic shunt with adaptively adjustable coating length also includes a balloon dilatation system, which includes a balloon and an inner core for threading a guide wire, the balloon is embedded in the tubular skeleton, the inner core axially passes through the balloon, and the raised inner core head end is clamped at the end of the coated stent for intrahepatic portosystemic shunt; the balloon is connected to a balloon connecting tube for an external pressure pump.

[0013] The beneficial effects of the present invention are:

[0014] After the coated stent of the present invention is placed, the coated stent is expanded by balloon dilation, and the coatings at both ends naturally curl from the curled sections toward the middle, and stop curling when blocked, so that the coating length is consistent with the liver parenchyma area, greatly reducing the adverse effects caused by the inconsistency between the coating length and the actual required length, and reducing the occurrence of complications. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic structural diagram of the stent graft of the present invention;

[0016] Figure 2 is a schematic diagram of the structure of a tubular skeleton;

[0017] Figure 3 It is a schematic diagram of the curling state of the self-curling section of the coating;

[0018] Figure 4 This is a schematic diagram of the in vivo state of the stent graft of the present invention;

[0019] Figure 5 It is a schematic diagram of the working state of the stent graft of the present invention;

[0020] Figure 6 This is a schematic diagram of the structure of a covered stent with an internal balloon dilatation system;

[0021] Figure 7 for Figure 6 sectional view of;

[0022] Figure 8 for Figure 6 sectional view of

[0023] Fig. 9 Schematic diagram of using built-in balloon dilatation system to release the covered stent;

[0024] Figure markings: 1- tubular skeleton, 101- lower bare stent segment, 2- coating, L21- self-curling segment on the coating, L22- middle fixed segment of the coating, L23- self-curling segment under the coating, 3- outer sheath, 4- balloon, 5- balloon connecting tube, 6- inner core, 601- inner core head end. DETAILED DESCRIPTION

[0025] The covered stent for intrahepatic portosystemic shunt with adaptively adjustable coating length of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0026] like Figures 1 to 3 As shown, a coated stent for intrahepatic portosystemic shunt with adaptively adjustable coating length comprises a tubular skeleton 1 and a coating 2, the coating 2 comprises an upper self-curling segment L21, a middle fixed segment L22 and a lower self-curling segment L23 connected in sequence, the middle fixed segment L22 is an inner and outer double-layer coating, fixed on the tubular skeleton 1 (i.e., the middle position of the tubular skeleton 1 is coated with inner and outer double-sided coating, fixed by a fixing method such as bonding, interweaving or spraying, the upper self-curling segment L21 and the lower self-curling segment L23 are both single-layer coatings, connected to the outer layer of the middle fixed segment L22), the upper self-curling segment L21 and the lower self-curling segment L23 are coated on the tubular skeleton 1, and the tubular skeleton 1 is located below the coating 2 to form a lower bare stent 101.

[0027] In this embodiment, the self-curling section L21 on the coating, the middle fixed section L22 on the coating, and the self-curling section L23 on the coating are made of polytetrafluoroethylene, which has a stable structure and is difficult to corrode. Among them, the self-curling section L21 on the coating and the self-curling section L23 on the coating are embedded with memory metal wires that can be curled according to the arc set by the molding. The length of the tubular skeleton 1 is 10 cm, the length of the middle fixed section L22 on the coating is 5 cm, the length of the self-curling section L21 on the coating and the self-curling section L23 on the coating are both 2 cm, and the length of the lower bare stent 101 is 1 cm.

[0028] The tubular skeleton 1 is a tubular structure woven from nickel-titanium wires.

[0029] In addition, if Figures 6 to 8 As shown, the coated stent for intrahepatic portosystemic shunt of the present invention is covered with an outer sheath 3 which plays a protective role.

[0030] The above-mentioned intrahepatic portal-systemic shunt covered stent also includes a balloon dilatation system, which includes a balloon 4 and an inner core 6 for threading a guide wire, wherein the balloon 4 is embedded in the tubular frame 1, the inner core 6 axially passes through the balloon 4, and the raised inner core head 601 is stuck at the end of the intrahepatic portal-systemic shunt covered stent. The balloon 4 is connected to a balloon connecting tube 5 for an external pressure pump.

[0031] The method of using the covered stent for intrahepatic portosystemic shunt of the present invention is as follows:

[0032] The coated stent and balloon dilatation system of the present invention are used in conjunction with the COOK RUPS100 sheath (or similar sheath). When in use, the outer sheath 3 of the coated stent that serves as a protection during transportation is discarded when entering the RUPS100 sheath. The coated stent and the built-in balloon dilatation system enter the designated area along the RUPS100 sheath. After the position is confirmed, a pressure pump is used to expand the balloon 4. After the balloon 4 is fully opened, the self-curling segments of the coating at both ends of the coated stent automatically curl along the sheath (when the self-curling segments of the coating are subjected to force and the ends become free, the memory metal wire embedded therein drives the self-curling segments of the coating to curl with the arc set during molding) until they are fixed in position after being obstructed. At this time, the coated area just covers the liver parenchyma, and the coated stent is completely released, such as Fig. 9 shown.

[0033] See also Figure 4 Before the balloon 4 is expanded, the coating area accounts for a large proportion (at this time, the self-curling segments of the coating at both ends tightly wrap the tubular frame 1), which affects the portal blood flow into the liver and is prone to form vortices (similar situations occur in the coating area of ​​traditional stents). Figure 5 After the balloon 4 is expanded, the self-curling segments of the coating at both ends of the coated stent curl into place to form a coated area that matches the liver parenchyma, does not affect the portal blood flow, and has a better shunt effect.

[0034] In the present invention, the stent graft has a built-in balloon dilatation system, which can realize one-piece molding after the stent graft is placed, thereby achieving the purpose of streamlining the operation.

[0035] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any replacement or transformation method that can be easily thought of by any technician familiar with the technical field within the scope of the technical method disclosed in the present invention should be covered within the protection scope of the present invention.

Claims

1. A covered stent for intrahepatic portosystemic shunt with adaptively adjustable coating length, comprising a tubular skeleton (1) and a coating (2), characterized in that: The coating (2) comprises an upper self-curling section (L21), an intermediate fixed section (L22) and a lower self-curling section (L23) connected in sequence, the intermediate fixed section (L22) being fixed on the tubular frame (1), the upper self-curling section (L21) and the lower self-curling section (L23) being wrapped on the tubular frame (1), and the tubular frame (1) being located below the coating (2) to form a lower bare stent (101); the upper self-curling section (L21), the intermediate fixed section (L22) and the lower self-curling section (L23) are made of polytetrafluoroethylene; the upper self-curling section (L21) and the lower self-curling section (L23) are The curved section (L23) is embedded with a memory metal wire that can be curled according to a set arc; the coated stent for intrahepatic portal-systemic shunt is covered with an outer sheath (3) that plays a protective role; it also includes a balloon dilatation system, the balloon dilatation system includes a balloon (4) and an inner core (6) for threading a guide wire, the balloon (4) is embedded in the tubular skeleton (1), the inner core (6) axially passes through the balloon (4), and the raised inner core head (601) is clamped at the end of the coated stent for intrahepatic portal-systemic shunt; the balloon (4) is connected to a balloon connecting tube (5) for an external pressure pump; the tubular skeleton (1) is a tubular structure woven from nickel-titanium metal wires.

2. The covered stent for intrahepatic portosystemic shunt with adaptively adjustable coating length according to claim 1, characterized in that: The length of the tubular skeleton (1) is 10 cm, the length of the middle fixed section (L22) of the coating is 5 cm, the length of the upper self-curling section (L21) of the coating and the lower self-curling section (L23) of the coating are both 2 cm, and the length of the lower bare stent (101) is 1 cm.

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