CN104887348B - Leakage stent graft system in the anti-I types of attached sponge structure - Google Patents

Abstract

The invention relates to an anti-type I endoleak stent graft system with a sponge structure, which is used for closing type I endoleaks, and is characterized in that it comprises: a metal mesh support layer matching the shape of arterial vessels; covered by the metal mesh The film layer on the support layer; and the spongy layer that is distributed on the proximal end of the outer side of the film layer or is distributed on the proximal end and the distal end of the outer side of the film layer at the same time, and the sponge layer is under the effect of self elasticity Fill in the gap formed between the inner wall of the arterial vessel and the covering layer. The anti-type I endoleak stent graft system with sponge structure of the present invention can close type I endoleak.

Description

Anti-type I endoleak stent-graft system with sponge structure

technical field

The invention relates to an anti-type I endoleak stent graft system with a sponge structure, which belongs to the field of medical devices.

Background technique

Aneurysm is one of the most common vascular diseases that cause disability and death. It can be found in any artery in the body, and it is more common in the elderly. Aneurysms can have a variety of sizes, shapes, and distributions. The Ad Hoc Committee on Reporting Standards of the Society for Vascular Surgery defines an aneurysm as a permanent artery with a diameter greater than 50% of the normal arterial diameter. Classification and standardization for clinical decision-making.

The earliest record of attempting to treat aneurysms dates back to the 3rd century AD. Until 1888, Matas et al. completed the first real aneurysm repair, that is, ligated branch arteries in the aneurysm cavity of the brachial aneurysm. In 1951, Dubost et al. completed the first case of aneurysm suturing repair. They resected the abdominal aortic aneurysm of a patient, and selected the thoracic aorta of a 20-year-old deceased donor as an allograft and transplanted it into the abdominal aorta. In a patient with an aortic aneurysm, the patient survived for 8 years after surgery. The open surgery for aneurysm repair has gradually been perfected and optimized in the following 40 years, but its perioperative mortality rate is still as high as 5%. In 1991, Parodi et al first reported the experience of repairing aortic aneurysm with artificial stent composite. After the Food and Drug Administration (FDA) approved the clinical application of endovascular grafts, aneurysms (including peripheral aneurysms and aortic aneurysms) underwent an evolution from open bypass repair to endovascular repair.

Compared with traditional open surgery, the use of covered stents for endovascular exclusion in the treatment of aneurysms, arterial dissection and other diseases has the advantages of less surgical trauma, faster postoperative recovery, and shorter hospital stay, but its unique complication—endoleak , so far cannot be completely avoided. Endoleak is one of the most important complications after endovascular exclusion, and its incidence rate is as high as 45%. Endoleaks can be divided into I-V types according to their mechanism of occurrence, and only Type I endoleaks related to the present invention will be introduced below. Type I endoleak refers to the leakage of blood into the aneurysm cavity through the proximal or distal end of the covered stent due to poor adhesion between the stent graft and the inner wall of the artery in the anchoring area. The incidence rate is about 10%. It can be found on intraoperative angiography. Because the existence of type I endoleak can lead to high pressure in the aneurysm cavity, continuous expansion of the aneurysm, and even the risk of rupture, it needs to be treated immediately during the operation. It is generally believed that the incidence of type I endoleak will be significantly increased when the proximal anchoring area is less than 10 mm, and/or the aneurysm neck angle is greater than 60°. The normal vessel wall ensures that the vascular stent is fully attached to it. Such a length of vessel wall is defined as the landing zone (LZ), including the proximal and distal LZs; the angulation of the neck refers to the central axis of the neck The angle formed with the central axis of the aortic trunk. At present, the general treatment methods for type I endoleaks found during surgery are: balloon expansion, addition of short-stent grafts, bare stents, or embolization techniques using cyanoacrylate, Onyx glue, coils, and fibrin glue . These techniques can handle most type I endoleaks; but in some cases it will be very difficult, such as: abdominal aortic aneurysm proximal anchoring zone is too short, adding a short stent-graft at the proximal end may affect Renal artery blood supply. Maldonado et al. summarized the current effects of the above methods in dealing with type I endoleaks: the success rate of cyanoacrylate embolic agents was 92.3%, that of proximal short-segment grafts was 80%, and that of coils was 75%. No matter which of the above treatment methods is adopted, there is not only a problem of success rate, but also a problem of a large increase in operation time and medical expenses. Moreover, the prolongation of operation time increases the risk of patients during operation and the incidence of postoperative infection, and the high medical expenses bring a high economic burden to patients and occupy more social resources.

Contents of the invention

In order to solve the above problems, the present invention adopts the following technical solutions:

An anti-type I endoleak stent-graft system with a sponge structure for sealing type I endoleaks, characterized in that it includes:

Metal mesh support layer matching the shape of arteries;

a coating layer covering the metal mesh support layer; and

The spongy layer distributed at the proximal end outside the covering layer or at the proximal end and distal end outside the covering layer at the same time, the sponge layer fills the inner wall of the arterial vessel and the covering film under the action of its own elasticity. gaps formed between the layers.

In addition, the anti-type I endoleak stent-graft system with sponge structure of the present invention may also have such a feature: wherein, the thickness of the sponge layer is in the range of 1mm-5mm.

In addition, the anti-type I endoleak stent-graft system with sponge structure of the present invention may also have such a feature: wherein, the material of the sponge layer is polyglycolide PGLA.

In addition, the anti-type I endoleak stent-graft system with sponge structure of the present invention may also have such a feature: wherein, the sponge layer does not exceed the edges of the ends of the metal mesh support layer and the film layer.

In addition, the anti-type I endoleak stent-graft system with a sponge structure of the present invention may also have such a feature: wherein, the sponge layer is made of a material capable of absorbing coagulation factors and blood cells such as platelets in blood.

In addition, the anti-type I endoleak stent-graft system with a sponge structure of the present invention may also have such a feature: wherein, the sponge layer has evenly distributed diamond-shaped depressions, and the longer diagonal line of the rhombus is aligned with the blood flow in the same direction.

Invention function and effect

According to the anti-type I endoleak stent-graft system with sponge structure of the present invention, when it is used to close the aneurysm cavity that aortic aneurysm forms, owing to also adopting sponge layer on the outside of coating layer, and sponge layer is elastic in itself. Under the action of the sponge, it fills in the gap formed between the inner wall and the covering layer, so that the blood flow cannot directly rush into the tumor cavity, and the blood in the sponge gap will coagulate after a period of time, thereby completely sealing the tumor cavity , making the tumor cavity enter a stable state.

Description of drawings

Fig. 1 is the overall structure schematic diagram of the anti-type I endoleak stent-graft system with sponge structure of the present invention;

2 is a schematic diagram of the internal structure of the anti-type I endoleak stent-graft system with a sponge structure of the present invention;

Fig. 3 is the cross-sectional view of the anti-type I endoleak stent-graft system attached to the sponge structure of the present invention;

Fig. 4 is the schematic diagram of the anti-type I endoleak stent-graft system with sponge structure of the present invention implanted into the blood vessel;

Fig. 5 is a schematic cross-sectional view at BB' in Fig. 4;

Fig. 6 is a schematic diagram of the two ends of the anti-type I endoleak stent-graft system with sponge structure attached to the sponge layer of the present invention; and

Fig. 7 is a schematic diagram of the anti-type I endoleak stent-graft system with sponge structure of the present invention, in which the sponge layer is a rhombus grid.

Detailed ways

Due to the formation of Type I endoleak, that is, due to poor adhesion between the stent covering and the inner wall of the artery in the anchoring area, there are many reasons for the blood to leak into the aneurysm cavity through the proximal end or the distal end of the covering stent. The anti-endoleak bracket with sponge structure can prevent type I endoleak caused by various reasons. In the specific embodiment, the description will be made only by taking the poor adherence between the stent covering and the inner wall of the artery in the anchoring area caused by the arteriosclerotic plaque as an example.

The specific implementation manners of the present invention will be described below in conjunction with the accompanying drawings.

<Example 1>

Fig. 1 is a schematic diagram of the overall structure of the anti-type I endoleak stent-graft system with a sponge structure of the present invention, and Fig. 2 is a schematic diagram of the internal structure of the anti-type I endoleak stent-graft system with a sponge structure of the present invention. As shown in FIG. 1 and FIG. 2 , the anti-type I endoleak stent-graft system 10 with a sponge structure has a metal mesh support layer 11 , a film layer 12 and a sponge layer 13 . The metal mesh support layer 11 is located in the innermost layer, the coating layer 12 covers the outer layer, and the sponge layer 13 is located in the outer layer of the proximal end of the coating layer 12 . The reason is that on the side facing the blood flow, the impact force of the blood flow is very strong, and facing the gap supported by the arteriosclerotic block, the blood flow is particularly easy to rush into the gap in this direction, while at the far end, Since the opening of the gap is along the direction of blood flow, it is difficult for blood to rush into the gap. Even if there is a gap, the blood flow in it is very slow. After a period of time, the blood in it will naturally coagulate, which is dangerous. Sex is very small. Therefore, no sponge layer may be provided at the distal end of the anti-type I endoleak stent-graft system 20 with a sponge structure, which can reduce the manufacturing cost.

The commonly used material for the coating layer 12 is polyester, also known as ethylene terephthalate. The material used for the sponge layer 13 is polyglycolide, English abbreviation PGLA. The PGLA material has the function of adsorbing blood cells such as coagulation factors and platelets. The sponge layer 13 is pasted on the coating layer.

3 is a cross-sectional view of the anti-type I endoleak stent-graft system with sponge structure of the present invention. As shown in FIG. 3 , the elastic sponge layer 13 is on the periphery of the coating layer 12 .

Fig. 4 is a schematic view of the anti-type I endoleak stent-graft system with a sponge structure of the present invention implanted into a blood vessel, and Fig. 5 is a schematic cross-sectional view of BB' in Fig. 4 . As shown in Figures 4 and 5, when the anti-type I endoleak stent-graft system 10 with a sponge structure is implanted in the blood vessel at the place where the aneurysm occurs, there are Arteriosclerotic block 15, the arteriosclerotic block 15 protrudes in the blood vessel wall, and the metal mesh support layer 11 and the coating layer 12 of the anti-I type endoleak stent graft system 10 with a sponge structure are pushed up, and the coating layer 12 A gap is formed between the inner wall of the blood vessel, and because the sponge layer 13 is elastic, it will be filled in the gap, and because the sponge layer itself has many pores. The flow rate of blood in the gap filled by the sponge layer is greatly reduced, and at the same time due to the effect of coagulation factors in the blood, the residual blood in the gap filled by the sponge layer will coagulate after a period of time, thereby sealing the gap.

In the case of gaps, there is another adverse effect, that is, because the gaps are always under the impact of blood flow, the endothelial cells in the inner wall of the blood vessels cannot grow into the inside of the stent, so that the edges of the stent cannot be covered by endothelial cells and thus communicate with the blood vessels. The inner skin is connected into one piece. After implanting the anti-type I endoleak stent-graft system 10 with a sponge structure of this embodiment, the epithelial cells on the blood vessel wall near the stent gap have sufficient time to grow into the attached The inner surface of the anti-type I endoleak stent-graft system 10 with a sponge structure finally completely covers the inner surface of the stent and connects with the vascular endothelium at both ends. As a result, the stent enters a stable state, the tumor cavity will not be filled with blood, and the tumor cavity will enter a stable state after the blood remaining in the tumor cavity coagulates, and then endothelial cells proliferate and grow into the tumor cavity, making the tumor cavity less likely to rupture .

The direction A in Figure 1 and Figure 5 both refers to the direction of arterial blood flow, the end close to the direction A is the proximal end, and the end far away from the direction A is the distal end. The length of the sponge layer 13 does not exceed the edges of the upper and lower ends of the metal mesh support layer and the coating layer. The reason for this setting is to prevent the sponge layer from protruding from the edge of the anti-type I endoleak stent-graft system 10 with the sponge structure, causing the blood flow here to coagulate, form a thrombus, and enter the blood vessel under the impact of the blood flow Embolism of blood vessels.

Implantation method of anti-type I endoleak stent-graft system with sponge structure:

The anti-type I endoleak stent-graft system 10 with sponge structure is installed on the balloon catheter, and delivered to the vascular lesion through the balloon catheter, and the pressure pump injects liquid to expand the balloon, and then stretches the anti-endoleak stent graft system 10 with the sponge structure. The type I endoleak stent-graft system 10 makes it close the blood vessels on both sides of the tumor cavity, and then withdraws the balloon catheter, so that the stent is permanently placed in the lesion to achieve the purpose of sealing the tumor cavity. The orientation of the stent in the balloon catheter should be such that the end with the spongy layer is located proximally in the vessel when installation is complete.

During the operation, X-ray contrast video is used to monitor the whole process of the catheter entering the aorta from the small artery in the human body and finally reaching the tumor cavity.

Function and effect of embodiment one

According to the anti-type I endoleak stent-graft system with a sponge structure in Embodiment 1, according to the anti-type I endoleak stent-graft system with a sponge structure of the present invention, since a sponge layer is also used outside the covering layer, And the sponge layer fills the gap formed between the inner wall and the covering layer under the action of its own elasticity. When there is an arteriosclerotic mass on the blood vessel wall, the elastic sponge layer will hold the metal mesh supported by the arteriosclerotic mass. The gap formed between the support layer and the covering layer and the inner wall of the blood vessel is filled, so that the blood flow cannot directly rush into the tumor cavity, and the blood in the spongy layer will solidify after a period of time, thereby completely sealing the tumor cavity, making The tumor cavity enters a stable state.

The porous sponge structure has three functions. On the one hand, it is a physical barrier, which greatly slows down the flow of blood here, thereby promoting coagulation. On the other hand, it is a chemical effect. PGLA can absorb blood cells such as coagulation factors and platelets, and further promote coagulation; At the same time, the grid structure also acts as a matrix for the formation of fibrosis, which is conducive to the growth of fibroblasts, thereby further stabilizing the tumor cavity.

In addition, since the length of the sponge layer 13 does not exceed the edges of the upper and lower ends of the metal mesh support layer and the coating layer, the sponge layer can be prevented from protruding from the edge of the anti-I-type endoleak stent-graft system 10 with a sponge structure, Cause the blood flow here to coagulate, form a thrombus, and enter the blood vessel under the impact of the blood flow to embolize the blood vessel.

The implantation method of the anti-type I endoleak stent-graft system 10 with sponge structure:

The anti-type I endoleak stent-graft system 10 with sponge structure is installed on the balloon catheter, and delivered to the vascular lesion through the balloon catheter, and the pressure pump injects liquid to expand the balloon, and then stretches the anti-endoleak stent graft system 10 with the sponge structure. The type I endoleak stent-graft system 10 makes it close the blood vessels on both sides of the tumor cavity, and then withdraws the balloon catheter, so that the stent is permanently placed in the lesion to achieve the purpose of sealing the tumor cavity.

During the operation, X-ray contrast video is used to monitor the whole process of the catheter entering the aorta from the small artery in the human body and finally reaching the tumor cavity.

<Example 2>

In this second embodiment, for the same structures as those of the above-mentioned embodiment, this modified example assigns the same numbers, and the same descriptions are omitted.

Fig. 6 is the schematic diagram that sponge layer is covered on the two ends of the anti-type I endoleak stent-graft system with sponge structure of the present invention, as shown in Fig. 6, the sponge layer of the anti-type I endoleak stent-graft system 20 with sponge structure 21 covers both ends of the anti-type I endoleak stent-graft system 20 with a sponge structure. The advantage of setting the fluff layer at the proximal end and the distal end at the same time is that it can further prevent type I endoleak at the distal end. Although the probability of this happening is very low, such setting can further enhance the safety of the stent.

<Example Three>

In the third embodiment, for the same structures as those in the above embodiment, the modification is assigned the same numbers and the same descriptions are omitted.

Fig. 7 is the schematic diagram that the sponge layer of the anti-type I endoleak stent-graft system with sponge structure of the present invention is a rhombus grid, as shown in Fig. 7, the anti-type I endoleak stent-graft system 30 with sponge structure The sponge layer has evenly arranged diamond-shaped grooves 33 . On the one hand, the diamond-shaped groove 33 can save the material used in the sponge. On the other hand, because the diamond-shaped groove 33 itself has a certain space, these spaces may just accommodate the arteriosclerosis after implantation. When the protruding edges between the diamond-shaped grooves 33 corresponded, the force used by the arteriosclerotic mass to prop up the sponge was also very small. There is less pressure on the blood vessel wall and less irritation to the blood vessel.

In addition, the coating layer of the present invention can also cover the inner side of the metal mesh support layer, so that the sponge layer is directly connected to the metal mesh support layer, and this lamination sequence can also achieve the technical effect of the present invention.

Claims (4)

1. leakage stent graft system, leaks for closing in I types in a kind of anti-I types of attached sponge structure, it is characterised in that bag Include：

The metal net shaped supporting layer to match with the arteries shape；

The coating layer being covered on the metal net shaped supporting layer；And

The proximal part being distributed on the outside of the coating layer or the proximal part and distal end that are distributed in simultaneously on the outside of the coating layer Spongy layer, the spongy layer is filled in the presence of natural resiliency between the arterial vascular inwall and the coating layer In the gap formed, slow down the blood flow in the gap and promote blood coagulation, fibroblast is grown into the gap,

Wherein, the material of the spongy layer is poly (glycolide-lactide) PGLA.

2. leakage stent graft system in the anti-I types of attached sponge structure according to claim 1, it is characterised in that：

Wherein, the thickness range of the spongy layer is 1mm-5mm.

3. leakage stent graft system in the anti-I types of attached sponge structure according to claim 1, it is characterised in that：

Wherein, the spongy layer is without departing from the metal net shaped supporting layer and the edge of the end of coating layer.

4. leakage stent graft system in the anti-I types of attached sponge structure according to claim 1, it is characterised in that：

Wherein, there is equally distributed diamond sunk on the spongy layer, and a longer diagonal for the rhombus with Blood flow direction is consistent.