Controllable vascular ring constrictor for large animals and experimental method

Abstract

The large animal controllable vascular ring constriction device comprises an elastic hoop, an inflatable air bag ring and an inflatable air pipe, the elastic hoop comprises an upper hoop and a lower hoop, an outer ring of the inflatable air bag ring is fixed to the upper hoop, a central hole of the inflatable air bag ring forms a coronary artery compression area, and the inflatable air pipe is fixed to the lower hoop. The side, facing the lower hoop, of the inflatable air bag ring is provided with a notch communicated with the coronary artery compression area to form a passageway, after the upper hoop and the lower hoop are opened, the coronary artery can enter the coronary artery compression area through the passageway, the size of the coronary artery compression area is reduced along with inflation of the inflatable air bag ring, and controllable compression of the coronary artery in the coronary artery compression area is achieved. When the inflatable air bag ring is in an uninflated state, the coronary artery compression area is larger than the outer diameter of the coronary artery, the device is fixed to the set position of a coronary artery system through the elastic hoop, meanwhile, the inflatable air bag ring and the pressure sensor are matched, controllability of blood vessel ring contraction and blood flow blocking is achieved, and therefore an acute and chronic myocardial ischemia model can be built according to needs.

Description

Technical Field

[0001] The invention belongs to the technical field of large animal model construction experimental equipment, and in particular relates to a controllable blood vessel constrictor for large animals and an experimental method. Background Art

[0002] Myocardial infarction is one of the serious clinical manifestations of coronary heart disease. Coronary heart disease is also called ischemic heart disease. Its mechanism of occurrence is: atherosclerosis of the coronary arteries causes stenosis or occlusion of the blood vessel lumen. As a result, the myocardium cannot get sufficient blood supply, and it will be damaged or even necrotic due to ischemia and hypoxia, thus causing heart disease.

[0003] When there is clinical evidence that a myocardial necrosis is completely caused by a myocardial ischemic event, myocardial infarction is considered to have occurred. Animal models are one of the effective means to study the pathophysiological mechanisms of human cardiovascular diseases and the development of related drugs, especially large animal models can obtain more reliable experimental results. Commonly used animal models for studying coronary heart disease include rodents such as mice, rats, and rabbits, as well as large animals such as pigs and monkeys. For rodents such as mice, rats, and rabbits, due to the relatively easy genetic manipulation, short gestation period, relatively low cost, and a large number of similarities with human genomics, proteomics and many other aspects of function, rodents represented by mice have become the first choice for establishing animal models in the field of cardiovascular research. However, the distribution and structure of mouse coronary arteries are very different from those of humans, so they are not very useful for the study of coronary heart disease. Large animal models, led by pigs, have great advantages in terms of volume, anatomical structure, heart development, heart rate reserve, excitation-contraction coupling and other anatomy and circulatory physiology. In addition, compared with large primates such as monkeys, pigs are easy to raise, have strong vitality, are docile, and have good surgical tolerance. Therefore, in recent years, the proportion of using pig myocardial infarction models has increased significantly in related studies on the specific mechanisms of myocardial infarction.

[0004] Currently, the schemes for pig myocardial infarction modeling can be divided into two categories: acute myocardial infarction modeling and chronic myocardial infarction modeling. The former mainly includes open-chest ligation, interventional modeling and drug modeling, while the modeling of chronic myocardial infarction mainly includes coronary artery constriction and chronic intracoronary stenosis.

[0005] 1. Coronary artery constriction method: After anesthesia, open-chest surgery is performed to expose the left ventricle and the left anterior descending coronary artery. The inner diameter of the coronary artery at the site to be ligated is measured using an echocardiogram, and the left anterior descending coronary artery is constricted using a non-damaging suture to narrow the left anterior descending coronary artery by 50%. Although this method can simulate myocardial infarction and is practical, it is difficult to control the degree of stenosis of the ligation in actual operation, it is difficult to establish a strict and unified ligation standard, and it is impossible to ensure the stability and consistency of the constructed model.

[0006] 2. Chronic intracoronary stenosis method: percutaneous intervention LAD implantation of deformable embolic material or use of balloons to mechanically squeeze and damage the vascular endothelium, which can gradually embolize the coronary artery over time and cause chronic myocardial ischemia. This method fits the clinical pathological process of coronary heart disease and is relatively easy to locate, but due to the long modeling time, the deformable embolic material in the blood vessel or the use of balloons is difficult to control or adjust its volume, and the degree of coronary stenosis is still difficult to control. In addition, this method has complicated interventional surgery and is not as simple and easy as open chest surgery.

[0007] 3. Drug modeling method: Currently commonly used drugs include posterior pituitary hormone (Pit), isoproterenol, and catecholamines, etc., mainly caused by drug effects It is generally believed that the drug-induced myocardial infarction model is simple and easy to replicate, with relatively low technical requirements, and can better simulate the vasoconstriction process during human myocardial infarction. However, the area of ​​myocardial infarction caused by drugs is difficult to measure, and it is difficult to identify the artery where the infarction occurs, and the effect is uncertain.

[0008] It can be seen that although the above-mentioned model construction schemes can achieve the modeling effect of myocardial infarction model, they cannot control the degree of vascular narrowing, it is difficult to control the pressure on the coronary artery at any time, and they cannot monitor the function of hemodynamic changes in real time. Therefore, it is impossible to control the degree of myocardial infarction and cannot meet the purpose of mechanism research involving different stages of myocardial infarction. Summary of the invention

[0009] The present invention solves the deficiencies of the prior art and provides a controllable vascular constrictor and an experimental method for large animals, which can solve the problem that the degree of vascular constriction is uncontrollable during myocardial infarction modeling in large animals.

[0010] To achieve the above-mentioned purpose, the present invention first proposes a controllable vascular constrictor for large animals, comprising an elastic clamp and an inflatable airbag ring, wherein the elastic clamp comprises an upper clamp and a lower clamp, the outer ring of the inflatable airbag ring is fixed on the upper clamp, the central hole of the inflatable airbag ring forms a coronary compression zone, and the inflatable airbag ring is provided with a notch connected to the coronary compression zone on the side facing the lower clamp to form an entrance and exit, after the upper clamp and the lower clamp are opened, the coronary artery can enter the coronary compression zone through the entrance and exit, the size of the coronary compression zone decreases as the inflatable airbag ring is inflated, thereby achieving controllable compression of the coronary artery in the coronary compression zone, and when the inflatable airbag ring is in an uninflated state, the coronary compression zone is larger than the outer diameter of the coronary artery.

[0011] In this embodiment, one end of the upper clamp and the lower clamp are connected by an elastic member to form a connection end, and the other end is detachably connected by a buckle.

[0012] In this embodiment, the buckle includes a sub-buckle arranged on the upper clamp and a mother buckle arranged on the lower clamp and matching the sub-buckle. In the initial state, under the action of the elastic member, the movable ends of the upper clamp and the lower clamp are opened to form an opening larger than the outer diameter of the coronary artery, and the coronary artery is inserted into the coronary compression zone between the upper clamp and the lower clamp through the opening; in the locked state, the sub-buckle of the upper clamp is clamped in the mother buckle of the lower clamp to achieve the locking of the upper clamp and the lower clamp; in the unlocked state, by pressing down on the upper clamp, the sub-buckle is separated from the mother buckle, and the upper clamp and the lower clamp are separated.

[0013] In this embodiment, an inflation port is provided on the inflatable airbag ring, an inflation air tube is installed in the inflation port of the inflatable airbag ring, and the inflation air tube is connected to an external inflation device.

[0014] In this embodiment, the inflation device is an inflation pressure monitoring inflation device.

[0015] In this embodiment, a pressure sensor for monitoring the air pressure inside the inflatable airbag ring is arranged inside the inflatable airbag ring, and the pressure sensor is connected to an inflation device for inflating the inflatable airbag ring through a controller.

[0016] The present invention also includes an experimental method using the above-mentioned large animal controllable vascular constrictor, which specifically includes the following steps:

[0017] S1. Simulation experiment:

[0018] Inject water into the free pig blood vessel so that the side wall pressure of the free pig blood vessel after water injection is the same as the average side wall pressure of the pig LAD under normal physiological conditions, then install the inflatable balloon ring buckle of the large animal controllable vascular constrictor on the free pig blood vessel, gradually increase the ring pressure of the inflatable balloon ring, measure the specific value of the inner diameter of the inflatable balloon ring every time the inner pressure is increased, and record the inner pressure and the corresponding inner diameter of the inflatable balloon ring one by one, and finally obtain a functional relationship between the two;

[0019] S2. Formal Experiment:

[0020] The large animal controllable vascular constrictor is installed outside the experimental pig coronary artery, and then the inflatable balloon ring is preliminarily inflated. The inflatable balloon ring preliminarily clamps the coronary artery, and the air pressure inside the inflatable balloon ring is monitored in real time. The functional relationship obtained in step S1 is used to determine the degree of constriction of the coronary blood vessel. When the experimental set constriction value is reached, subsequent experiments and data monitoring can be carried out.

[0021] Due to the adoption of the above structure, this structure has the following advantages:

[0022] 1. An inflatable balloon ring is set up by using the device. Through inflation, the coronary compression zone formed by the central hole of the inflatable balloon ring is reduced, thereby realizing controllable compression of the coronary artery in the coronary compression zone. When in use, the pressure is monitored in real time through the inflation pressure monitoring provided by the inflation device. Through simulation experiments, the relationship curve between the pressure in the inflatable balloon ring and the cross-sectional area of ​​the coronary artery after the coronary artery is placed in the coronary compression zone is measured, thereby converting the pressure in the inflatable balloon ring into the compression area of ​​the coronary artery. In this way, the compression area of ​​the coronary artery can be accurately controlled by controlling the inflation pressure value, so as to achieve the process of hindering the blood flow or even blocking the blood flow, thereby constructing an acute or chronic myocardial ischemia model as needed.

[0023] 2. The elastic clamp of the device is made of metal or plastic and is opened and closed by means of a buckle, so that it can be conveniently fixed on the blood vessel. An inflation port is provided on the inflatable airbag ring inside the elastic clamp. The inflation port serves as a connection port with the inflatable air tube. The inflatable air tube can be detachably installed on the inflation port to realize the inflation of the fixed inflatable airbag ring.

[0024] In summary, the device is fixed to the coronary system detection site through an elastic clamp, and cooperates with an inflatable balloon ring and a pressure sensor to achieve controllable blood flow blockage by vascular ring contraction, so that acute and chronic myocardial ischemia models can be constructed as needed. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A perspective view of the present invention;

[0026] Figure 2 It is a front view of the present invention.

[0027] In the figure: 1. elastic clamp; 11. upper clamp; 12. lower clamp; 13. elastic member; 14. sub-buckle; 15. main buckle; 2. inflatable airbag ring; 21. entrance and exit; 3. inflatable trachea; 4. coronary compression area. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0030] like Figure 1 As shown in or 2, a controllable vascular constrictor for large animals includes an elastic clamp 1, an inflatable airbag ring 2 and an inflatable trachea 3.

[0031] The elastic clamp 1 comprises an upper clamp 11 and a lower clamp 12, one end of the upper clamp 11 and the lower clamp 12 are connected by an elastic member 13 to form a connecting end, and the other end is respectively provided with a matching sub-buckle 14 and a mother buckle 15 to form a movable end. In the initial state, under the action of the elastic member 13, the movable ends of the upper clamp 11 and the lower clamp 12 are opened to form an opening larger than the outer diameter of the coronary artery, so as to facilitate the coronary artery to be clamped between the upper clamp 11 and the lower clamp 12; in the locked state, the elasticity of the elastic member 13 is overcome, and the sub-buckle 14 of the upper clamp 11 is clamped in the mother buckle 15 of the lower clamp 12 to achieve the locking of the upper clamp 11 and the lower clamp 12; in the unlocked state, the upper clamp 11 is pressed down to make the sub-buckle 14 disengage from the mother buckle 15, and the upper clamp 11 and the lower clamp 12 are separated under the elastic action of the elastic member 13.

[0032] Furthermore, the inflatable airbag ring 2 is fixed in the upper clamp 11 of the elastic clamp 1. Specifically, the inner cavities of the upper clamp 11 and the lower clamp 12 are combined into a full circle. The circumference of the upper clamp 11 is greater than the circumference of the lower clamp 12. The outer diameter of the inflatable airbag ring 2 matches the inner diameter of the upper clamp 11. The inner ring center hole of the inflatable airbag ring 2 forms a coronary compression zone 4. The inflatable airbag ring 2 is not a full circle ring. The inflatable airbag ring 2 is provided on the side facing the lower clamp 12. The notch connected to the coronary compression zone 4 forms an entrance and exit. After the upper clamp 11 and the lower clamp 12 are opened, the coronary artery can enter the coronary compression zone 4 through the entrance and exit after entering the elastic clamp 1. The size of the coronary compression zone 4 decreases as the inflatable balloon ring 2 is inflated, thereby achieving controllable compression of the coronary artery in the coronary compression zone 4. When the inflatable balloon ring 2 is not inflated, the coronary compression zone 4 is larger than the outer diameter of the coronary artery, thereby facilitating entry into the coronary artery.

[0033] The inflatable airbag ring 2 is provided with an inflating port, and an inflating air tube 3 is installed in the inflating port of the inflatable airbag ring 2. The inflating air tube 3 is connected to an external inflating device, and the inflating device can monitor the inflation pressure. Furthermore, a pressure sensor for monitoring the air pressure inside the inflatable airbag ring 2 is provided inside the inflatable airbag ring 2, and the pressure sensor is connected to the inflating device through a controller; or the inflatable airbag ring 2 is made of a deformable material, and its internal air pressure can be measured by connecting the outer end of the inflatable air tube 3 to a pressure monitoring device.

[0034] When in use, the relationship curve between the pressure monitored by the pressure sensor and the cross-sectional area of ​​the coronary artery is measured through simulation experiments. Thus, the pressure inside the inflatable balloon ring 2 can be converted into the compression area of ​​the coronary artery. In this way, the compression area of ​​the coronary artery can be accurately controlled by controlling the inflation pressure value. Specifically, water is injected into the free pig blood vessel to ensure that the side wall pressure of the blood vessel is the same as the average side wall pressure of the pig LAD under normal physiological conditions. The device is buckled on the free pig blood vessel, and the ring pressure of the inflatable balloon ring 2 is gradually increased. At the same time, the specific value of the inner diameter of the inflatable balloon ring 2 is measured, and the inner pressure is matched with the inner diameter of the inflatable balloon ring 2 one by one, and the functional relationship between the two is obtained. In subsequent experiments, the degree of coronary blood vessel shrinkage can be judged by comparing the functional relationship, so as to achieve a controllable and knowable modeling purpose.

[0035] The specific installation process is as follows:

[0036] First, the upper clamp 11 is pressed down to make the sub-buckle 14 disengage from the main buckle 15. Under the elastic action of the elastic member 13, the upper clamp 11 and the lower clamp 12 are separated. Then, the device is mounted outside the coronary artery so that the coronary artery enters the coronary compression zone 4 through the gap. Then, the sub-buckle 14 of the upper clamp 11 is clamped in the main buckle 15 of the lower clamp 12 to achieve the locking of the upper clamp 11 and the lower clamp 12. Then, the inflation device preliminarily inflates the inflatable airbag ring 2 so that the inflatable airbag ring 2 preliminarily clamps the coronary artery. After clamping, the subsequent experiment can be continued.

[0037] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A controllable vascular constrictor for large animals, characterized in that: The invention comprises an elastic clamp (1) and an inflatable airbag ring (2), wherein the elastic clamp (1) comprises an upper clamp (11) and a lower clamp (12), the outer ring of the inflatable airbag ring (2) is fixed on the upper clamp (11), the central hole of the inflatable airbag ring (2) forms a coronary compression zone (4), and the inflatable airbag ring (2) is provided with a notch communicating with the coronary compression zone (4) on the side facing the lower clamp (12) to form an entrance (21), after the upper clamp (11) and the lower clamp (12) are opened, the coronary artery can enter the coronary compression zone (4) through the entrance (21), and the size of the coronary compression zone (4) decreases as the inflatable airbag ring (2) is inflated, thereby achieving controllable compression of the coronary artery in the coronary compression zone (4).

2. A controllable vascular constrictor for large animals according to claim 1, characterized in that: One end of the upper clamp (11) and the lower clamp (12) are connected by an elastic member (13) to form a connection end, and the other end is a movable end and is detachably connected by a buckle.

3. A controllable vascular constrictor for large animals according to claim 2, characterized in that: The buckle comprises a sub-buckle (14) arranged on the upper clamp (11) and a female buckle (15) arranged on the lower clamp (12) and matching with the sub-buckle (14).

4. The controllable vascular constrictor for large animals according to claim 1, characterized in that: The inflatable airbag ring (2) is provided with an inflating port, an inflating air pipe (3) is installed in the inflating port of the inflatable airbag ring (2), and the inflating air pipe (3) is connected to an external inflating device.

5. A controllable vascular constrictor for large animals according to claim 4, characterized in that: The inflation device is an inflation device that monitors inflation pressure.

6. A controllable vascular constrictor for large animals according to any one of claims 1 to 5, characterized in that: A pressure sensor for monitoring the air pressure inside the inflatable airbag ring (2) is arranged inside the inflatable airbag ring (2), and the pressure sensor is connected to an inflation device for inflating the inflatable airbag ring (2) through a controller.

7. An experimental method for performing vascular constriction using the controllable vascular constrictor for large animals as claimed in claim 6, characterized in that: The specific steps include: S1. Simulation experiment: The free pig blood vessel is injected with water so that the side wall pressure of the free pig blood vessel after the injection is the same as the average side wall pressure of the pig LAD under normal physiological conditions, and then the inflatable balloon ring (2) of the large animal controllable vascular constrictor is buckled on the free pig blood vessel, and the inner ring pressure of the inflatable balloon ring (2) is gradually increased. The specific value of the inner diameter of the inflatable balloon ring (2) is measured every time the inner pressure is increased, and the inner ring pressure and the corresponding inner diameter of the inflatable balloon ring (2) are recorded one by one, and finally a functional relationship between the two is obtained; S2. Formal Experiment: The large animal controllable vascular constrictor is installed outside the experimental pig coronary artery, and then the inflatable balloon ring (2) is preliminarily inflated. The inflatable balloon ring (2) preliminarily clamps the coronary artery, and the air pressure inside the inflatable balloon ring (2) is monitored in real time. The functional relationship obtained in step S1 is used to determine the degree of constriction of the coronary blood vessel. When the constriction value set in the experiment is reached, subsequent experiments and data monitoring can be carried out.

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