A phased balloon-expandable vertebral artery stent system and method for precise positioning

Abstract

The present invention relates to a staged balloon-expandable vertebral artery stent system and method with precise positioning, belonging to the technical field of balloon stent positioning in vertebral artery surgery. The present invention is provided with a special-shaped balloon. On the one hand, through the differential design of the size structures of the proximal balloon and the distal balloon, physical limit and positioning are achieved. It can not only ensure that the position of the special-shaped balloon can accurately reach the designated position at the connection of the stenosis site and the subclavian artery and perform automatic calibration when inserted, but also effectively avoid the influence of the amplitude of the special-shaped balloon and the stent when the catheter is withdrawn. On the other hand, by controlling the speed and magnitude of the advancing air pressure, the sequential deformation processes of the proximal balloon and the distal balloon are realized to ensure the fixation of the stent after sufficient positioning. In addition, the present invention is also provided with a radiopaque marker to assist in positioning, improving the precision of balloon stent positioning during surgery, avoiding the amplitude phenomenon of catheter withdrawal, and the negative impacts brought by damaging or cutting plaques, and having high promotion value.

Description

Technical Field

[0001] The present invention relates to a precisely positioned staged balloon expansion vertebral artery stent system and method, belonging to the technical field of balloon stent positioning in vertebral artery surgery. Background Art

[0002] The vertebral artery is a blood vessel that supplies the back of the brain. When the vertebral artery is not supplied with enough blood, it will show symptoms of vertebral artery stenosis (or occlusion) and cause intermittent and paroxysmal neurological dysfunction, mainly manifested as symptoms of the brainstem, cerebellum and occipital lobe.

[0003] Currently, stent surgery is commonly used to treat vertebral artery stenosis. This procedure involves placing a stent into the blood vessel to dilate the narrowed vessel and restore blood flow. During the stent expansion process, a balloon is usually installed on the catheter to prop up the stent.

[0004] However, existing stent surgeries usually use a catheter to deliver the entire balloon and stent to the stenosis. This method not only makes it difficult to accurately position the balloon and stent at the stenosis, but also when the catheter is withdrawn after the stent is expanded, the friction between the catheter and the balloon will cause the stent and balloon to move due to the withdrawal of the catheter. This movement will inevitably cause the originally expanded stenosis to lose its original positioning to a certain extent, resulting in an inaccurate expansion position, affecting the quality of the operation and the patient's subsequent condition.

[0005] Therefore, there is an urgent need to find an effective method that can accurately locate the stenosis when delivering the balloon and stent during vertebral artery surgery, and ensure that the balloon and stent will not move when the catheter is withdrawn. There is no record of relevant means in the existing technology. Summary of the Invention

[0006] To solve the above problems, in a first aspect, the present invention provides a precisely positioned, staged balloon-expandable vertebral artery stent system for use at the junction of the subclavian artery and the vertebral artery stenosis, comprising:

[0007] A special-shaped balloon, wherein the special-shaped balloon has a deformable distal balloon and a proximal balloon, wherein the balloon width of the distal balloon in a natural state is smaller than the balloon width of the proximal balloon, and the balloon width of the proximal balloon after being fully expanded is greater than the width of the stenosis and cannot pass through the stenosis, the distal balloon is externally sheathed with a stent and is used to expand the stenosis, and the proximal balloon is connected to the proximal end of the distal balloon and is used for positioning; a partition portion is provided inside the connection between the distal balloon and the proximal balloon that can be destroyed when the target air pressure is reached; and

[0008] a catheter passing through the distal balloon, the proximal balloon, and the partition; and

[0009] A pressure pump is connected to the proximal end of the catheter and communicated with the special-shaped balloon.

[0010] It should be understood that the proximal end can be the end outside the body that is close to the operator or inserted into the catheter, and the distal end can be the end inside the body that is away from the operator; the stenosis of the vertebral artery can also include plaques, and the special-shaped balloon will undergo elastic deformation due to changes in internal air pressure, and the deformation includes but is not limited to expansion and contraction (or natural state); wherein, when the distal balloon is deformed by expansion, the stenosis and the plaque in the stenosis will be supported by the distal balloon together, thereby facilitating the installation and fixation of the stent; since the proximal balloon will not be able to pass through the stenosis after the expansion and deformation and will press against the proximal outlet of the stenosis, it can ensure that only the distal balloon and the stent on the distal balloon are in the stenosis, and at the same time, when the catheter is pulled out proximally, the distal balloon and the stent can be prevented from being moved by friction in the withdrawal direction, so that the proximal balloon can achieve a better positioning effect.

[0011] It should be understood that the partition is the partition of the internal connection between the proximal balloon and the distal balloon, and the partition is a membrane or sheet structure. The partition will only be broken and destroyed when the target air pressure is reached and the proximal balloon is fully expanded (the target air pressure can be set according to the air pressure value required for the proximal balloon to be fully expanded); that is, when the air pressure is increased from 0 to the target air pressure, only the proximal balloon is continuously pressurized and deformed to expand. Since the balloon width of the proximal balloon itself is greater than that of the distal balloon, the deformation of the proximal balloon before reaching the target air pressure is sufficient to withstand the stenosis. The proximal outlet cannot enter the stenosis, which is equivalent to a preliminary positioning calibration (this positioning calibration is different from other positioning methods. Since the proximal balloon will gradually elastically abut the proximal outlet of the stenosis during the expansion process, even if a part of the proximal balloon extends into the stenosis in the unexpanded state, it will be squeezed out of the proximal outlet of the stenosis under the action of elastic deformation, thereby calibrating the positioning of the error deviation and ensuring the accuracy of the preliminary positioning); when the air pressure reaches the target pressure, the partition part will be destroyed, and the air pressure will be quickly introduced into the distal balloon, and then the distal balloon will gradually expand.

[0012] Preferably, the distal balloon is provided with markers corresponding to the proximal and distal positions of the stent and the proximal position of the proximal balloon, and the markers can facilitate imaging equipment to locate the position of the special-shaped balloon made of transparent material.

[0013] In the present invention, the balloon width refers to the maximum dimension of the proximal balloon or the distal balloon perpendicular to the catheter direction. By default, in the natural state, the balloon width of the proximal balloon is slightly larger than the balloon width of the distal balloon.

[0014] Furthermore, the balloon length of the distal balloon is greater than that of the proximal balloon. This setting can, on the one hand, save the occupied space of the proximal balloon in the subclavian artery, and on the other hand, prevent the proximal balloon from being displaced by the curved catheter extending into the subclavian artery when the balloon length of the proximal balloon is too large (to avoid the situation of balloon shape distortion or misalignment); the balloon length refers to the dimension of the proximal balloon or distal balloon along the catheter direction in the natural state and the expanded state.

[0015] Preferably, the balloon width of the proximal balloon after being fully expanded is 1-2 mm wider than the stenosis site.

[0016] Furthermore, there is also a radiopaque marker at the connection between the distal balloon and the proximal balloon, and the radiopaque marker can be detected by X-rays; preferably, the material of the radiopaque marker can be platinum-iridium alloy; it should be understood that when the special-shaped balloon is extended through the catheter to the vicinity of the stenosis site, the positioning and calibration are mainly carried out through the elastic deformation of the proximal balloon. This radiopaque marker can be an auxiliary positioning method, and through X-ray technology, it can be determined whether the connection between the proximal balloon and the distal balloon reaches the proximal outlet of the stenosis site, thereby further improving the positioning accuracy.

[0017] In the second aspect, the present invention also provides a method for accurately controlling the positioning when a phased balloon dilation vertebral artery stent system with accurate positioning is used to dilate the stenosis site at the connection of the stenosis sites of the subclavian artery and the vertebral artery, including the following steps:

[0018] Step 1: Install the special-shaped balloon on the catheter and connect the proximal end of the catheter to a pressure pump. Through the catheter, extend the special-shaped balloon from the subclavian artery to the connection of the stenosis sites of the subclavian artery and the vertebral artery, so that the distal balloon is located in the stenosis site and the proximal balloon is located in the subclavian artery near the distal end of the stenosis site.

[0019] Step 2: Push the pressure pump to apply air pressure to the proximal balloon of the special-shaped balloon through the catheter. Due to the existence of the partition, before the target air pressure is reached inside the proximal balloon, the proximal balloon will gradually expand to abut against the subclavian artery at the proximal inlet edge of the stenosis site, so that the entire special-shaped balloon is positioned through the proximal balloon and the distal balloon is completely located inside the stenosis site. In step 2, the distal balloon is always in a non-expanded state.

[0020] Step 3: Continue to apply air pressure to the target air pressure and above. When the target air pressure is reached inside the proximal balloon, the partition will be damaged by the air pressure, and then the air pressure can quickly fill into the distal balloon, causing the distal balloon to gradually expand until the stent is expanded to the target degree, thereby completing the dilation process of the stenosis site.

[0021] Step 4: After the air pressure reaches the full air pressure capable of filling the whole special-shaped balloon, withdraw the catheter; since the special-shaped balloon is in a positioned state, the stent will not produce an amplitude phenomenon in the catheter direction due to the action of withdrawing the catheter.

[0022] Furthermore, the air pressures in Step 2 to Step 4 are controlled by the dial and scale of a pressure pump; preferably, the target air pressure is 2 Pa, and the full air pressure is 6 - 8 Pa; the advancing speed of the pressure pump during the process of the air pressure rising from 0 to the target air pressure is greater than the advancing speed of the pressure pump during the process of the air pressure rising from the target air pressure to the full air pressure, which can ensure that the proximal balloon is quickly positioned and then the stent is slowly and fully expanded.

[0023] Advantages of the present invention:

[0024] The present invention is provided with a special-shaped balloon. On the one hand, through the differential design of the size structures of the proximal balloon and the distal balloon, physical limit and positioning are realized. It can not only ensure that the position of the special-shaped balloon can accurately reach the specified position at the connection of the narrow part and the subclavian artery and perform automatic calibration when inserted, but also effectively avoid the amplitude influence on the special-shaped balloon and the stent when the catheter is withdrawn. On the other hand, by controlling the speed and magnitude of the advancing air pressure, the sequential deformation processes of the proximal balloon and the distal balloon are realized to ensure the fixation of the stent after full positioning. In addition, the present invention is also provided with a developing mark to assist in positioning, which improves the accuracy of the balloon stent positioning during the operation, also avoids the amplitude phenomenon of withdrawing the catheter and the negative impacts brought by damaging or cutting the plaque, and has high promotion value. Description of the drawings

[0025] Figure 1 It is a schematic diagram of the overall structure acting on the connection of the vertebral artery and the subclavian artery in an embodiment of the present invention.

[0026] Figure 2 It is for an embodiment of the present invention where the special-shaped balloon is located Figure 1 near the narrow part.

[0027] Figure 3 It is a schematic diagram of the change process of the special-shaped balloon and the air flow movement in an embodiment of the present invention, where a is the natural state (or contracted and deflated), b is the state where only the proximal balloon is expanded when the target air pressure is not reached, and c is the state where the special-shaped balloon is fully expanded.

[0028] In the figure, 1: special-shaped balloon, 2: stent, 3: partition part, 4: developing mark, 5: catheter, 6: pressure pump, 7: marker, 11: proximal balloon, 12: distal balloon. Detailed implementation manners

[0029] Example 1

[0030] like Figure 1 - Figure 2 As shown, the present invention provides a precisely positioned staged balloon-expandable vertebral artery stent system for the junction of the subclavian artery and the vertebral artery stenosis, comprising:

[0031] A special-shaped balloon 1, wherein the special-shaped balloon 1 has a deformable distal balloon 12 and a proximal balloon 11. In a natural state, the proximal balloon 11 is 1-2 mm wider than the stenosis. When the proximal balloon 11 is fully expanded, the balloon width is greater than the width of the stenosis and cannot pass through the stenosis. The distal balloon 12 is sheathed with a stent 2 and is used to expand the stenosis. The proximal balloon 11 is connected to the proximal end of the distal balloon 12 and is used for positioning. A partition 3 that can be destroyed when the target air pressure is reached is provided inside the connection between the distal balloon 12 and the proximal balloon 11. Markers 7 are provided at the proximal and distal positions of the distal balloon 12 corresponding to the stent 2 and the proximal position of the proximal balloon 11.

[0032] The catheter 5 passes through the distal balloon 12, the proximal balloon 11 and the partition 3; and

[0033] The pressure pump 6 is connected to the proximal end of the catheter 5 and communicated with the special-shaped balloon 1 .

[0034] Since the proximal balloon 11 cannot pass through the narrow part after expansion and is deformed, it will press against the proximal exit of the narrow part, thus ensuring that only the distal balloon 12 and the stent 2 on the distal balloon 12 are in the narrow part. At the same time, when the catheter 5 is pulled out proximally, the distal balloon 12 and the stent are prevented from being moved by friction in the withdrawal direction, so that the proximal balloon 11 can achieve a better positioning effect.

[0035] The partition 3 is a partition at the internal connection between the proximal balloon 11 and the distal balloon 12. The partition 3 will be broken and destroyed only when the target air pressure is reached and the proximal balloon 11 is fully expanded (the target air pressure can be set according to the air pressure value required for the proximal balloon 11 to be fully expanded); that is, when the air pressure is increased from 0 to the target air pressure, only the proximal balloon 11 is continuously pressurized and deformed to expand. Since the balloon width of the proximal balloon 11 itself is greater than that of the distal balloon 12, the deformation of the proximal balloon 11 before reaching the target air pressure is sufficient to resist the proximal outlet of the stenosis and The inability to enter the narrow part is equivalent to performing a preliminary positioning calibration (this positioning calibration is different from other positioning methods. Since the proximal balloon 11 will gradually elastically abut the proximal outlet of the narrow part during the expansion process, even if a part of the proximal balloon 11 extends into the narrow part in the unexpanded state, it will be squeezed out of the proximal outlet 11 of the narrow part under the action of elastic deformation, thereby calibrating the positioning of the error deviation and ensuring the accuracy of the preliminary positioning); when the air pressure reaches the target pressure, the partition part 3 will be destroyed, and the air pressure will be quickly introduced into the distal balloon 12, and then the distal balloon 12 will gradually expand.

[0036] The length of the distal balloon 12 is greater than the length of the proximal balloon 11. This configuration can save the space occupied by the proximal balloon 11 in the subclavian artery on the one hand, and can prevent the proximal balloon 11 from being misaligned by the curved catheter 5 inserted into the subclavian artery when the balloon length is too large (avoiding the situation where the balloon shape is distorted or misplaced, for example, in Figure 1 The middle catheter 5 bends to the left, and if the proximal balloon 11 is too large, it will also deviate to the left, thereby failing to ensure the accuracy of positioning the proximal balloon 11 to the right of the proximal outlet of the stenosis).

[0037] like Figure 2 As shown, the connection between the distal balloon 12 and the proximal balloon 11 may have a developing mark 4, and the developing mark 4 can be detected by X-rays; the developing mark 4 is a platinum-iridium alloy; it should be understood that when the special-shaped balloon 1 is inserted into the vicinity of the stenosis through the catheter 5, positioning and calibration are mainly carried out through the elastic deformation of the proximal balloon 11, and the developing mark 4 can be a secondary, auxiliary positioning method, and X-ray technology is used to determine whether the connection between the proximal balloon 11 and the distal balloon 12 reaches the proximal exit of the stenosis, thereby further improving the accuracy of positioning.

[0038] Example 2

[0039] like Figure 1 - Figure 3As shown, the target air pressure is set to 2 Pa and the full air pressure is set to 6-8 Pa. The method for precisely controlling the positioning of the precisely positioned staged balloon expandable vertebral artery stent system in Example 1 when performing expansion at the stenosis site at the junction of the subclavian artery and the vertebral artery includes the following steps:

[0040] Step 1: Install the special-shaped balloon 1 on the catheter 5 and connect the proximal end of the catheter 5 to the pressure pump 6. Insert the special-shaped balloon 1 through the catheter 5 from the subclavian artery to the junction of the subclavian artery and the vertebral artery stenosis, so that the distal balloon 12 is located at the stenosis and the proximal balloon 11 is located in the subclavian artery near the distal end of the stenosis.

[0041] Step 2: The pressure pump 6 is pushed to apply air pressure to the proximal balloon 11 of the special-shaped balloon 1 through the catheter 5 (the pushing time here is 4 seconds). Due to the presence of the partition 3, before the target air pressure is reached inside the proximal balloon 11, the proximal balloon 11 will gradually expand to the subclavian artery at the proximal entrance edge of the stenosis, so that the entire special-shaped balloon 1 is positioned by the proximal balloon 11 and the distal balloon 12 is completely located in the stenosis. In step 2, the distal balloon 12 is always in a non-expanded state;

[0042] Step 3: Continue to apply air pressure to or above the target pressure (the pushing time here is 15-20 seconds). When the target pressure is reached inside the proximal balloon 11, the partition 3 is destroyed by the air pressure. Then, the air pressure can be quickly filled into the distal balloon 12, causing the distal balloon 12 to gradually expand until the stent 2 is expanded to the target degree, thereby completing the expansion process of the stenosis.

[0043] Step 4: After the air pressure reaches the full pressure that can fill the entire special-shaped balloon 1, withdraw the catheter; since the special-shaped balloon 1 is in a positioned state, the stent will not generate an amplitude movement in the direction of the catheter 5 due to the action of withdrawing the catheter 5.

[0044] Furthermore, the air pressure in steps 2 to 4 is controlled by the dial and scale of the pressure pump 6; the pressure pump propulsion speed in the process of increasing the air pressure from 0 to the target air pressure is greater than the pressure pump propulsion speed in the process of increasing the air pressure from the target air pressure to the full air pressure, which can ensure that the proximal balloon is quickly positioned so that the stent is slowly and fully expanded.

[0045] Although the present invention has been disclosed above in terms of preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A precisely positioned, staged balloon-expandable vertebral artery stent system for the junction of the subclavian artery and the vertebral artery stenosis, characterized in that: include: The special-shaped balloon comprises a deformable distal balloon and a proximal balloon; in a natural state, the width of the proximal balloon after being fully expanded is greater than the width of the stenosis and cannot pass through the stenosis; the width of the proximal balloon after being fully expanded is 1-2 mm wider than the stenosis; the distal balloon is sheathed with a stent and is used to dilate the stenosis; the proximal balloon is connected to the proximal end of the distal balloon and is used for positioning; a partition portion that can be destroyed when the target air pressure is reached is provided inside the connection between the distal balloon and the proximal balloon; the balloon length of the distal balloon is greater than that of the proximal balloon; the connection between the distal balloon and the proximal balloon also has a development mark, and the development mark can be detected by X-rays; as well as a catheter passing through the distal balloon, the proximal balloon, and the partition portion; as well as a pressure pump connected to the proximal end of the catheter and in communication with the special-shaped balloon; The partition portion is a membrane or sheet structure, and will be broken or destroyed only when the target air pressure is reached and the proximal balloon is fully expanded.

2. The staged balloon expandable vertebral artery stent system according to claim 1, characterized in that: The material of the development mark is platinum-iridium alloy.

3. The staged balloon expandable vertebral artery stent system according to claim 1, characterized in that: The distal position and distal position of the distal balloon corresponding to the stent, and the proximal position of the proximal balloon are both provided with markers.

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