CN116173285A - Biodegradable vascular embolism body - Google Patents

Abstract

The invention relates to a biodegradable vascular plug body, belonging to the technical field of medical appliances. The plug body is in a linear structure, and is sequentially provided with a core layer, a main body layer, a coagulation promoting layer and a self-expanding material coating from inside to outside along the radial direction; the core layer, the body layer, the coagulant layer and the self-expanding material coating comprise an absorbable material; the core layer includes a developer therein. The vascular plug body provided by the invention has good trafficability and can be developed, and can reach a vascular perforation position timely and accurately; can be fixed on a vascular target point, and avoids displacement caused by blood flow impact, thereby minimizing the potential influence of the plug body on the non-perforated blood vessel and avoiding iatrogenic myocardial infarction area expansion. The vascular embolism body adopts biodegradable materials, so that potential safety hazards caused by long-term foreign matter retention in a human body are avoided.

Description

Biodegradable vascular embolism body

Technical Field

The invention relates to a biodegradable vascular plug body, belonging to the technical field of medical appliances.

Background

Coronary atherosclerotic heart disease (coronary heart disease) is an ischemic heart disease caused by stenosis and occlusion of the lumen of the coronary artery as a result of the progression of an atherosclerotic lesion. At present, the prevalence rate, the total number of patients and the death rate of coronary heart diseases in China still increase, and the coronary heart disease is one of the main diseases which endanger the life and health of people. Coronary intervention therapy has become a main means for relieving symptoms, improving prognosis and improving life quality of coronary heart disease patients by virtue of the advantages of definite curative effect, small wound, rapid postoperative recovery and the like, and the total annual coronary intervention therapy quantity in China breaks through one million cases. Coronary perforation is a condition in which the wall of a coronary artery breaks during an interventional procedure due to various causes, causing blood to flow out of the vessel through the broken wall of the vessel. The past research suggests that the incidence rate of coronary perforation is 0.1% -0.9% in the coronary intervention treatment process, and serious complications such as acute cardiac tamponade, acute myocardial infarction and the like can be caused, so that the success rate of coronary intervention treatment is reduced, the risk of emergency coronary bypass is increased, and if the patient life is discovered to be untimely or mishandled or even endangered, the death rate can reach 9% at most.

The main treatment means for clinically blocking coronary perforation and rupture at present comprise: the saccule is expanded continuously under low pressure to block the opening, and the covered stent, vascular embolism, surgical repair and other methods are partially implanted into the perforation. The continuous low-pressure expansion of the saccule is carried to the near end of the perforation part to expand at the pressure of 2-6atm, and the expansion time is determined to be 10-30 minutes according to the tolerance condition of the patient. The covered stent is mainly used for blocking the perforation of a large blood vessel at the proximal section, but due to poor trafficability of the covered stent, the covered stent often fails to block because of being unable to reach the blocking part in calcification or distortion lesions, and meanwhile, the risk of restenosis in the covered stent is obviously increased after the covered stent is implanted. The vascular embolism principle is mainly applicable to the perforation of a distal segment blood vessel with a smaller diameter, and no targeted embolic material is available clinically at present, and commonly used embolic materials comprise microcoil, gelatin sponge, autologous adipose tissue and the like. Gelatin sponge and autologous adipose tissue cannot be developed under rays, have poor visibility, are blind to operate, often need repeated embolism for many times, and even can cause non-perforation vascular embolism to enlarge myocardial necrosis area. The spring ring has the advantage of visibility, but because the metal has rigidity, the situation of difficult release still exists in twisted blood vessels and extremely far-end small blood vessels, the spring ring has no biocompatibility, potential hidden danger exists in the long-term foreign matter retention in coronary arteries, and more importantly, the spring ring lacks self-expansion function, has a coagulation accelerating effect which is inferior to that of gelatin sponge and autologous adipose tissue, and often has escape phenomenon in the using process, so that the blocking is incomplete. Therefore, in order to overcome the defects of the vascular embolism technology in the prior art, the technical field needs to obtain a biodegradable vascular embolism body which has good trafficability, can reach a vascular perforation position in time to perform a function, and can enable medical staff to accurately release embolic materials under X-ray fluoroscopy to rapidly and effectively embolize a target blood vessel.

Disclosure of Invention

The invention aims to solve the technical problems that how to obtain a biodegradable vascular plug body, not only has good trafficability, can reach a vascular perforation position in time to play a role, but also can enable medical staff to accurately release the vascular plug body under X-ray perspective and rapidly and effectively plug a target blood vessel.

In order to solve the above-mentioned problem, the technical scheme adopted by the invention is to provide a biodegradable vascular plug body, the appearance of the plug body is a linear structure, and a core layer, a main body layer, a coagulation promoting layer and a self-expanding material coating are sequentially arranged from inside to outside along the radial direction; the core layer, the body layer, the coagulant layer and the self-expanding material coating comprise an absorbable material; the core layer includes a developer therein.

Preferably, the self-expanding material coating is axially provided in the middle of the periphery of the setting accelerator layer.

Preferably, a portion of the set accelerator layer is provided on the outer surface of the plug body.

Preferably, the core layer comprises a mixture of an absorbable polymer material and a developer.

Preferably, the absorbable polymeric material of the core layer comprises polyglycolic acid, polidocarone or p-dioxanone.

Preferably, the developer is barium sulfate.

Preferably, the resorbable material of the body layer comprises polyglycolic acid, polidocarone, or p-dioxanone.

Preferably, the procoagulant layer comprises chitosan, chitosan derivatives, human coagulation factors or thrombin.

Preferably, the self-expanding material coating comprises polyethylene glycol, chitosan or sodium carboxymethyl cellulose.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention provides a flexible vascular embolism apparatus, which has good trafficability, can rapidly pass through complex vascular lesions such as twists, calcifications and the like under the assistance of a microcatheter, and can timely reach vascular perforation positions to play a role.

2. The X-ray developable material is arranged in the vascular plug body, so that medical staff can accurately release the plug body under X-ray fluoroscopy, the released plug body is fixed on a vascular target point by the self-expansion coating on the outermost layer of the plug body, and the displacement of the instrument caused by blood flow impact is avoided, thereby minimizing the potential influence of the plug body on a non-perforated blood vessel and avoiding the expansion of the iatrogenic myocardial infarction area.

3. The vascular plug body provided by the invention is made of biodegradable materials, and after the vascular plug function is completed, the vascular plug body is completely degraded into substances such as carbon dioxide, water, urea, amino acid and the like within 2-3 months, so that potential safety hazards caused by long-term foreign matter retention in a human body are avoided.

Drawings

FIG. 1 is a schematic cross-sectional view of a biodegradable vascular occlusion body according to the present invention.

FIG. 2 is a schematic longitudinal cross-sectional view of a biodegradable vessel plug according to the present invention.

Reference numerals: 1. a core layer; 2. a body layer; 3. a coagulation promoting layer; 4. a coating of self-expanding material.

Detailed Description

In order to make the invention more comprehensible, preferred embodiments accompanied with the present invention are described in detail as follows:

as shown in fig. 1 and 2, the invention provides a biodegradable vascular plug body, the appearance of the plug body is a linear structure, and a core layer 1, a main body layer 2, a coagulation promoting layer 3 and a self-expanding material coating 4 are sequentially arranged from inside to outside along the radial direction; the core layer 1, the body layer 2, the coagulant layer 3 and the self-expanding material coating 4 comprise an absorbable material; the core layer 1 includes a developer therein. The self-expanding material coating 4 is axially provided in the middle of the outer periphery of the setting accelerator layer 3. The partial coagulation promoting layer 3 is arranged on the outer surface of the plug body. The core layer 1 comprises a mixture of an absorbable polymer material and a developer. The absorbable polymer material of the core layer 1 comprises polyglycolic acid, polifeprosan or p-dioxanone; the developer is barium sulfate. The resorbable material of the body layer 2 comprises polyglycolic acid, polidocarone or p-dioxanone. The procoagulant layer 3 comprises chitosan, chitosan derivative, human coagulation factor or thrombin. The self-expanding material coating 4 comprises polyethylene glycol, chitosan or sodium carboxymethyl cellulose.

The coronary embolism materials commonly used in clinic at present comprise microcoils, gelatin sponges, autologous adipose tissues and the like. In the using process of the materials, the defects of poor trafficability, no biocompatibility, poor visibility and the like exist, so that not only is the vascular embolism efficiency influenced, but also the non-target vascular embolism is possibly caused, and the myocardial necrosis area is enlarged. Aiming at the defects of the prior art, the invention designs a novel vascular embolism instrument, the flexible wire-like structure ensures that the instrument has good trafficability, the components of the developer are increased to improve the visibility of the instrument, the complete biocompatibility is realized by using the biodegradable material, and simultaneously, the embolism efficiency is ensured by using the coagulation promoting material and the self-expanding material, so that the escape phenomenon is avoided.

In order to overcome the defects in the prior art, the invention provides a biodegradable vascular plug body which is in a linear structure, and the cross section of the vascular plug body comprises a core layer, a main body layer, a coagulation promoting layer and a four-layer wrapping structure of a self-expanding material coating from inside to outside; the central area of the core layer is a mixture of absorbable polymer material and developer; the main body layer is an absorbable synthetic wire with good flexibility; the coagulation promoting layer is made of absorbable material; the coating of self-expanding material is located in an intermediate section outside the setting accelerator layer.

The absorbable polymer material forming the core layer comprises polyglycolic acid, polifeprosan and p-dioxanone, and the developer is barium sulfate;

the absorbable polymer material forming the main body layer comprises polyglycolic acid, polifeprosan and p-dioxanone; the polymer material is a material commonly used in products such as tissue engineering scaffolds, sutures and the like, and can be degraded and completely absorbed in human bodies.

Alternative materials for the procoagulant layer include chitosan, carboxymethyl chitosan, carboxyethyl chitosan, human coagulation factor, thrombin. Wherein, the chitosan and the derivatives thereof have natural positive amino groups, which can promote the aggregation of red blood cells and induce thrombosis, and the chitosan and the derivatives thereof can be gradually degraded in human body to form micromolecular monosaccharides which are then absorbed by the human body; human coagulation factors, thrombin and the like are procoagulant drugs commonly used clinically.

The self-expanding material coating can be selected from polyethylene glycol, chitosan, sodium carboxymethyl cellulose or hydrogel layer prepared from the above materials through chemical crosslinking. The chitosan and the derivatives thereof, and the sodium carboxymethyl cellulose generally have better hydrophilicity and solubility, and the hydrogel layer formed after chemical crosslinking can keep the original shape, absorb moisture and exert the volume expansion effect.

As shown in fig. 1 and 2, the present invention provides a biodegradable vascular occlusion body, which is a linear structure with a length of 10mm and a diameter of 0.2mm, and the cross section of the vascular occlusion body comprises a 4-layer structure from inside to outside: the innermost central area is a degradable core layer 1 with X-ray developing function, the second main body layer 2 is an absorbable synthetic line with good flexibility, the third layer is an absorbable coagulation promoting layer 3, and the outermost layer of the middle section of the embolic body along the long axis is a fourth layer: is a degradable self-expanding material coating 4.

The core layer 1 of the innermost layer adopts an absorbable polymer material polyglycolic acid and a developer barium sulfate; the absorbable synthetic thread of the second main body layer 2 adopts polyglycolic acid; the coagulation promoting layer 3 is chitosan; the chitosan and the derivatives thereof have natural positive amino groups, can promote erythrocyte aggregation and induce thrombosis, can be gradually degraded in human bodies to form micromolecular monosaccharides, and are then absorbed by the human bodies; the self-expanding material coating 4 adopts chitosan; the chitosan and the derivatives thereof, and the sodium carboxymethyl cellulose have better hydrophilicity and solubility, and the hydrogel layer formed after chemical crosslinking can keep the original shape, absorb moisture and exert the volume expansion effect.

The invention is used as follows:

when the distal end of the coronary artery is perforated, the coronary artery guide wire is sent into the microcatheter to the proximal end of the perforation position, the coronary artery guide wire is withdrawn, and the vascular plug body is sent to the perforation position through the microcatheter under the X-ray perspective. The embolic body contacts with human blood after reaching the vascular perforation, the middle section of the outermost layer of the embolic body is self-expanded, the embolic body is blocked and fixed at a vascular target point and blocks blood flow, and the third layer of procoagulant coating induces local thrombosis to completely block the perforated blood vessel.

Subsequently, the constituent materials of the plug body are broken in the molecular chain of the human body, the molecular weight is reduced, the constituent materials are gradually changed into oligomers or monomers, then the oligomers or monomers are completely absorbed by the human body, the normal metabolic process of the human body is entered, and the final degradation products comprise carbon dioxide, water, urea and amino acid.

While the invention has been described with respect to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Equivalent embodiments of the present invention will be apparent to those skilled in the art having the benefit of the teachings disclosed herein, when considered in the light of the foregoing disclosure, and without departing from the spirit and scope of the invention; meanwhile, any equivalent changes, modifications and evolution of the above embodiments according to the essential technology of the present invention still fall within the scope of the technical solution of the present invention.

Claims (9)

1. A biodegradable vascular plug body is characterized in that the appearance of the plug body is a linear structure, and a core layer, a main body layer, a coagulation promoting layer and a self-expanding material coating are sequentially arranged from inside to outside along the radial direction; the core layer, the body layer, the coagulant layer and the self-expanding material coating comprise an absorbable material; the core layer includes a developer therein.

2. A biodegradable vessel occlusion according to claim 1, wherein said self-expanding material coating is axially provided in the middle of the periphery of the procoagulant layer.

3. A biodegradable vessel occlusion body according to claim 1, wherein part of said procoagulant layer is provided on the outer surface of the occlusion body.

4. The biodegradable vessel occlusion of claim 1, wherein said core layer comprises a mixture of absorbable polymer material and a developing agent.

5. A biodegradable vessel occlusion according to claim 4, wherein said absorbable polymer material of said core layer comprises polyglycolic acid, poliglecaprone or p-dioxanone.

6. A biodegradable vessel occlusion body according to claim 1, wherein said developing agent is barium sulfate.

7. A biodegradable vessel occlusion according to claim 1, wherein said absorbable material of said body layer comprises polyglycolic acid, policarbolone or p-dioxanone.

8. A biodegradable vascular plug according to claim 1, wherein said procoagulant layer comprises chitosan, a chitosan derivative, a human coagulation factor or thrombin.

9. A biodegradable vessel occlusion according to claim 1, wherein said self-expanding material coating comprises polyethylene glycol, chitosan or sodium carboxymethyl cellulose.

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