CN212816651U

CN212816651U - TIPS (tip over-stent graft) capable of automatically adjusting blood pressure

Info

Publication number: CN212816651U
Application number: CN202020512703.3U
Authority: CN
Inventors: 李虎; 黄兴龙; 丁峰; 顾浩栋; 徐硕
Original assignee: Shanghai Hongpai Medical Technology Co Ltd
Current assignee: Shanghai Hongpai Medical Technology Co Ltd
Priority date: 2020-04-09
Filing date: 2020-04-09
Publication date: 2021-03-30
Anticipated expiration: 2030-04-09

Abstract

The utility model relates to a but TIPS tectorial membrane support of automatically regulated blood flow pressure in medical instrument field comprises naked support and support internal diameter adjusting structure, and support internal diameter adjusting structure both ends respectively have a development structure. The inner diameter adjusting mechanism of the bracket in the utility model can automatically adjust the inner diameter of the product according to the pressure of portal vein blood flow, when the pressure of portal vein rises, the inner diameter of the bracket becomes larger, the blood flow in the bracket is increased, and the bleeding of the tissue of a patient caused by the excessive rise of the pressure of portal vein can be prevented; when portal vein pressure is reduced, the inner diameter of the stent is reduced, blood flow in the stent is reduced, and incidence of hepatic encephalopathy after TIPS operation can be prevented. The product has simple and reliable structure, and the change of the inner diameter adjusting structure of the bracket is in smooth transition, thereby reducing the incidence of thrombus formation in the bracket.

Description

TIPS (tip over-stent graft) capable of automatically adjusting blood pressure

Technical Field

The patent of the utility model relates to a medical instrument, in particular to a transjugular intrahepatic portal puncture stent (TIPS stent) capable of automatically adjusting blood pressure.

Background

Hepatic cirrhosis Portal Hypertension (PHT) is a group of clinical syndromes in which portal venous pressure is increased (> 15 mmHg) due to various causes such as viral hepatitis or bulgarian syndrome, and collateral circulation is formed due to the blocked blood flow of the portal venous system. Liver cirrhosis portal hypertension can cause esophageal-gastric fundus vein rupture bleeding, refractory ascites, hepatic encephalopathy, hepatorenal syndrome and other complications. At present, when patients with portal hypertension and fundus gastrorrhagia caused by portal hypertension are treated clinically, a jugular intrahepatic puncture operation is usually adopted, a tectorial membrane stent is implanted between the portal vein and the hepatic vein, and a new blood flow channel is established to reduce the portal hypertension. Transjugular intrahepatic portal vein stent shunt (TIPS) has the characteristics of small wound, few complications, safety and the like, is an effective method for treating PHT (percutaneous transluminal coronary intervention), particularly for patients with upper gastrointestinal hemorrhage caused by esophageal and gastric fundus varicose rupture, and has definite clinical curative effect.

However, complications cannot be ignored after performing TIPS surgery. The increase in hepatic encephalopathy and the failure of shunt channel function are major limitations of TIPS procedures. Although the use of TIPS stent-grafts improves the long-term patency of the shunt channel, there is still a high incidence of both complications.

The incidence of hepatic encephalopathy is increased because nitrogen-containing substances (mainly blood NH3/NH4 +) in vivo directly enter the systemic circulation without liver detoxification during TIPS surgery due to the establishment of a shunt channel, so that the blood ammonia is increased, and the increase of the blood ammonia concentration causes the imbalance of excitatory and inhibitory neurotransmitters in the brain, which is manifested as mental excitation or inhibition. In clinical practice, experts have found that PPG < 12 mmHg increases the risk of hepatic encephalopathy in patients; PPG > 12 mmHg, in turn, increases the risk of bleeding in patients. Patent CN 207412270U describes a current limiting device for TIPS operation stent, which can prevent hepatic encephalopathy and hepatic failure by adjusting the internal diameter of the implanted stent by using a diameter regulator when the diameter of the prepared stent is not matched with the patient according to the specific situation of the patient in the operation. However, the stent has the internal diameter adjusted in vitro, and once the stent is implanted into a human body, the stent form cannot be adjusted in time according to the postoperative reaction of a patient, so the stent has low practicability. Similarly, the combined structure of the three-section stent described in patent CN 205885581U allows the middle conical stent to be replaced by a stent with different diameter according to the patient's condition. The shape can not be adjusted after the operation, and the practicability is not high. Patent CN 108814779 a describes a TIPS covered stent with a valve structure, in which the valve is opened and closed by a spring or an external power component, so as to control the blood pressure. This configuration can cause long term trauma to the patient and the valve can disrupt blood flow causing thrombus to form around the valve, especially on the back side of the valve, leading to valve failure and even pulmonary embolism. Patent CN 109953780 a describes a balloon-embedded stent graft, which is inflated or released with a liquid to achieve the effect of reducing or enlarging the inner diameter of the stent graft, thereby regulating the blood flow rate. The injection tip needs to be embedded under the skin of the patient. This design also results in long term wound and risk of infection.

There are various reasons for failure of the shunt after TIPS surgery. Acute thrombosis in the shunt; blood vortex in the shunt causes pseudointimal hyperplasia; problems with stent placement result in "caps" and the like. Patent CN 2873140Y describes a combined stent structure of a bare stent and a covered stent. Patent CN 109662804 a describes a stent structure with bare stent at both ends and covered stent in the middle. However, the stents of both of the above patents only reduce bile leakage and the "capping" problem of the stent port, and the inside of the stent is still prone to thrombosis and excessive intimal hyperplasia.

Disclosure of Invention

Appear as above after implanting for improving the TIPS support the hepatic encephalopathy incidence increase and the condition that the subchannel became invalid, the utility model provides a but TIPS tectorial membrane support of automatically regulated blood pressure, this support both ends are naked support, middle support internal diameter regulation structure that is. The stent inner diameter adjusting structure consists of a covering film and a stent, and the covering film in the stent inner diameter adjusting structure is provided with a drug coating, so that thrombosis and excessive intimal hyperplasia on the inner surface can be prevented.

The bare stent is formed by weaving nickel-titanium wires or cutting a nickel-titanium tube by laser.

The coating film is made of ePTFE (expanded polytetrafluoroethylene), PET (polyethylene terephthalate), silicone, or the like.

The inner diameter of the support can be automatically adjusted according to the change of blood pressure.

The stent in the stent inner diameter adjusting structure can be integrated with the covering film, the inner diameter of the middle of the covering film structure is smaller than the inner diameters of the two sides, and the thickness of the middle of the covering film in the structure is thicker than the thicknesses of the two sides and is in a smooth gradual change shape.

The film-coated material with the integrated structure is a porous reticular microstructure and has good elasticity and flexibility.

The middle support of the support inner diameter adjusting structure can be in a split structure with the covering film.

The inner diameter adjusting structure of the stent can be composed of a stent and a tectorial membrane with different radial supporting forces, and the radial supporting force of the middle section of the stent is smaller than the radial supporting forces at two ends.

The stent may have a lattice density or lattice cross-sectional area in the middle of the stent that is less than the two ends of the stent.

The inner diameter adjusting structure of the support can be composed of supports with different diameters, and the diameter of the middle section of each support is smaller than that of the supports at the two ends.

The stent in the stent inner diameter adjusting structure can be a tapered structure or a dumbbell-shaped structure with gradually changed diameters.

The inner diameter adjusting structure of the support can be a combined structure of a film covering, the support and the spring pieces, the spring piece structure is a radial inner bending structure, the inner diameter of the inner diameter adjusting structure of the support can be reduced due to the structure, and the inner diameter of the inner diameter adjusting structure of the support can be enlarged due to the radial pressure effect of the spring piece structure when the spring piece structure is subjected to blood flow high pressure.

The inner diameter of the stent inner diameter adjusting structure can change along with the change of blood flow pressure. When the portal vein pressure is more than 12 mmHg, the inner diameter of the stent inner diameter adjusting structure is expanded by the internal blood flow pressure, so that the inner diameter is enlarged, and the portal vein pressure is reduced by increasing the blood flow volume; when the portal vein pressure is less than 12 mmHg, the inner diameter adjusting structure of the stent is influenced by the compression force of the liver tissue or the elastic structure in the stent, the diameter is reduced to the original size, and the portal vein blood flow is limited.

The inner diameter of the inner diameter adjusting structure of the bracket is 3-15mm, preferably, the inner diameter is 7-9mm under low blood pressure, and the inner diameter is 9-12mm under high blood pressure.

The two ends of the inner diameter adjusting structure of the bracket are provided with the developing structures, so that the bracket can be accurately positioned when being released.

The inner and outer surfaces of the coating film in the inner diameter adjusting structure of the stent are coated with drug coatings, and the drugs can be anticoagulant drugs or antiplatelet drugs, anti-cell proliferation drugs and the like. Including heparin, aspirin, thrombolytic enzyme, rapamycin, paclitaxel, etc.

The utility model discloses an effective benefit is: the inner diameter of the product is automatically adjusted according to the portal vein blood flow pressure. When the portal vein pressure is increased, the inner diameter of the bracket is enlarged, the blood flow in the bracket is increased, and the tissue bleeding of a patient caused by the excessive increase of the portal vein pressure can be prevented; when portal vein pressure is reduced, the inner diameter of the stent is reduced, blood flow in the stent is reduced, and incidence of hepatic encephalopathy after TIPS operation can be prevented. The product has simple and reliable structure, and the change of the inner diameter adjusting structure of the bracket is in smooth transition, thereby reducing the incidence of thrombus formation in the bracket.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic view of the structure of fig. 1 when the blood pressure is increased.

Fig. 3 is a schematic structural diagram of another embodiment of the present invention.

Fig. 4 is a schematic structural diagram of the embodiment of fig. 3 when the blood pressure is increased.

Fig. 5 is a schematic structural view of an embodiment of the present invention including a spring plate member.

Fig. 6 is a schematic structural diagram of the embodiment of fig. 5 when the blood pressure is increased.

Detailed Description

The invention is further described below with reference to the accompanying drawings:

as shown in figure 1, the utility model discloses constitute by naked support 1 in both ends and middle support internal diameter adjusting structure 2, support internal diameter adjusting structure 2 comprises support 21 and tectorial membrane 3, and support internal diameter adjusting structure 2 both ends respectively have a development structure 4. The bare stent 1 is braided into a zigzag structure by nickel-titanium wires, and the structure of the stent 21 is consistent with that of the bare stent 1 and is integrally processed with the bare stent 1. The outer surface of the stent 21 is a plane tectorial membrane, the inner surface is the tectorial membrane 3, the thickness of the middle section of the tectorial membrane 3 is thicker than the thickness of the two ends, and the middle section is in a smooth gradual change shape. The film covering 3 is made of a porous reticular microstructure and has good elasticity and flexibility. The structure of the cover film 3 can be squeezed to become thinner when receiving increased blood pressure, and the inner diameter of the stent inner diameter adjusting structure 2 can be enlarged (as shown in fig. 2), so that more blood can pass through. After the blood pressure on the stent inner diameter adjusting structure 2 is reduced, the thickness of the tectorial membrane 3 can be gradually restored to the original state, thereby automatically adjusting the blood flow passing through the stent inner diameter adjusting structure 2. The inner surface of the film covering material is coated with a heparin coating, and heparin molecules are combined with the macromolecule bottom layer in a covalent bond mode.

As shown in fig. 3, for another embodiment of the present invention, the embodiment is composed of a bare stent 1 and a stent inner diameter adjusting structure 5 at two ends, and there is a developing structure 4 at each end of the stent inner diameter adjusting structure 5. The stent inner diameter adjusting structure 5 consists of a stent 51 and an outer surface coating, the stent 51 is woven by nickel-titanium wires into a 'T' -shaped structure, and two ends of the stent 51 consist of a dumbbell-shaped structure 511 and a straight section 512 with gradually changed diameters. The structure of the membrane section 5 may have a gradually larger inner diameter (as shown in fig. 4) when exposed to increased blood pressure, so as to allow more blood to pass through the structure of the head end 511 and the structure of the flat section 512. After the pressure of blood on the stent inner diameter adjusting structure 5 is reduced, the inner diameter of the head end 511 structure and the straight section 512 structure can be gradually restored, so that the blood flow passing through the stent inner diameter adjusting structure 5 can be automatically adjusted. The outer surface of the film covering material is coated with a paclitaxel drug coating.

As shown in fig. 5, for the embodiment of the present invention containing the spring plate structure, the present embodiment is composed of the two-end bare bracket 1 and the bracket inner diameter adjusting structure 6. The inner diameter adjusting structure 6 of the bracket is composed of a bracket 61 and a spring piece 62, and two ends of the inner diameter adjusting structure 6 of the bracket are respectively provided with a developing structure 4. The stent 61 has the same structure as the bare stent 1 and is a laser cutting stent structure. The outer surface of the bracket 61 is covered with a layer of film, the spring leaf 62 is in a radial inward bending structure, and a gap 64 is formed between the bracket 61 and the spring leaf 62. The inner diameter of the stent structure 6 is gradually increased when exposed to increased blood pressure (as shown in FIG. 6) to allow more blood to pass through the spring plate 62. After the blood pressure on the stent inner diameter adjusting structure 6 is reduced, the inner diameter formed by the spring leaf 62 can be gradually restored to the original shape, thereby automatically adjusting the blood flow passing through the stent inner diameter adjusting structure 6. The outer surface of the coating material is coated with a rapamycin drug coating.

In the embodiment, the inner diameter gradient section of the stent inner diameter adjusting structure is 8-10mm, the narrowest part in the middle of the covering film is 8mm, and the two sides of the covering film are 10 mm. The inner surface of the film covering material is coated with a drug coating, the drug coating comprises heparin, aspirin, thrombolytic enzyme, rapamycin, paclitaxel and the like, and the drug coating is combined with the macromolecule bottom layer in a covalent bond mode.

The above, only be the utility model discloses a typical example, do not be used for the restriction the utility model discloses, the fan is in the utility model discloses an improve on the basis and the example of extension all be within the scope of protection of the utility model.

Claims

1. The TIPS covered stent capable of automatically adjusting blood flow pressure consists of a bare stent and a stent inner diameter adjusting structure, and is characterized in that the stent inner diameter adjusting structure consists of a covering membrane and a stent, the inner diameter of the middle of the covering membrane structure is smaller than the inner diameters of two sides and is in a smooth gradual change shape, two ends of the stent inner diameter adjusting structure respectively contain a developing structure, and the covering membrane is provided with a drug coating.

2. A TIPS stent graft according to claim 1, wherein the inner diameter of the stent graft adjustment mechanism comprises a stent graft and a stent with different radial support forces, the radial support force in the middle of the stent graft being less than the radial support force at the ends.

3. A TIPS stent graft according to claim 2, wherein the stent graft has a lattice density or lattice cross-sectional area in the middle of the stent that is smaller than the ends of the stent.

4. A TIPS stent graft capable of automatically regulating blood flow pressure according to claim 1, wherein the inner diameter regulating structure of the stent is a tapered structure or a dumbbell-shaped structure with gradually changed diameter, and the diameter of the middle section of the stent is smaller than that of the stents at both ends.

5. A TIPS stent graft according to claim 4, wherein the inner diameter of the stent in the inner diameter adjusting configuration is such that the thickness of the stent graft is greater in the middle of the stent graft than on both sides of the stent graft and is of a smoothly tapering shape.

6. A TIPS stent graft according to claim 1, wherein the means for adjusting the inner diameter of the stent graft comprises a combination of a stent graft, a stent and a spring plate.

7. A TIPS stent graft according to claim 6, wherein the spring means is a radially inwardly curved spring.

8. A TIPS stent graft according to claim 1, wherein the inner diameter of the stent inner diameter adjusting structure is adapted to change with the change of the blood pressure, and when the portal vein pressure is higher than 12 mmHg, the inner diameter of the stent inner diameter adjusting structure is expanded by the internal blood pressure to become larger, and the portal vein pressure is decreased by the increase of the blood flow; when the portal vein pressure is less than 12 mmHg, the stent inner diameter adjusting structure is influenced by the compression force of the liver tissue or the elastic structure in the stent, and the inner diameter is reduced to the original size.

9. A TIPS stent graft according to claim 1, wherein the inner diameter of the inner diameter stent diameter adjusting structure is in the range of 3-15 mm.

10. A TIPS stent graft of claim 1, wherein the drug coating is selected from the group consisting of anticoagulant, antiplatelet, and anti-cell proliferation.