Catheter assembly and method of releasing a stent

Abstract

This invention discloses a catheter assembly and a method for releasing a stent, comprising a delivery catheter for delivering a stent, and a positioning catheter for the catheter assembly. The positioning catheter includes a first end and a second end, and the delivery catheter includes an output end for delivering the stent. The first end is connected to the output end, and the end of the second end is circular, with at least three reference points distributed on the end of the second end. By fixing the catheter assembly to the coronary sinus wall outside the coronary ostium, making the end of the second end flush with the coronary ostium, and by adjusting the direction of the angiography machine, the three reference points are aligned in a straight line on the angiography machine image. The angiography machine's viewing angle, the end of the second end of the positioning catheter, and the coronary ostium are all aligned. At this point, stent delivery and release are performed. By observing the angiography machine, the stent is accurately released to the coronary ostium, avoiding excessive stent dislodgement or failure to completely cover the coronary ostium, thus ensuring accurate stent positioning.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more specifically to a method for releasing a catheter assembly and a stent. Background Technology

[0002] Coronary artery ostial lesions are a high-risk type of coronary artery disease, and stent implantation is one of its routine treatments. Currently, the standard clinical approach is to use tangential angiography to locate the stent, releasing it with the proximal end protruding 1-2 mm from the coronary ostium. However, due to the varying angles of the coronary ostium in different patients, interventional procedures often present challenges such as difficulty in localization and selection of the angiographic angle. This can lead to prolonged stent retention at the coronary ostium, obstructing coronary blood flow and potentially causing serious adverse cardiovascular events. Furthermore, inaccurate stent localization after deployment can result in excessive stent detachment or failure to completely cover the coronary ostium, severely impacting the patient's long-term prognosis. Therefore, a more precise stent localization method is needed to improve the success rate and safety of stent implantation. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the defect of inaccurate stent release positioning in the prior art, and to provide a method for releasing catheter assembly and stent.

[0004] The present invention solves the above-mentioned technical problems by means of the following technical solution: a catheter assembly, which includes a delivery catheter for delivering a stent, the catheter assembly further includes a positioning catheter, the positioning catheter includes a first end and a second end, the delivery catheter includes an output end for delivering the stent, the first end is connected to the output end, the end of the second end is circular, and at least three reference objects are distributed on the end of the second end.

[0005] In this approach, the catheter assembly is fixed to the coronary sinus wall outside the coronary ostium, ensuring that the end of the second end is flush with the coronary ostium. By adjusting the direction of the angiography machine, the three reference points on the angiography machine image are aligned in a straight line. The angiography machine is positioned at the angiographic tangent of the end of the second end, meaning that the angiography machine's viewing angle, the end of the second end of the positioning catheter, and the coronary ostium are all flush. At this point, the stent is delivered and released. By observing the angiography machine, the stent can be accurately released to the coronary ostium, avoiding excessive stent dislodgement or failure to completely cover the coronary ostium, thus ensuring accurate stent positioning.

[0006] Preferably, at least three of the reference objects are equally spaced at the end of the second end.

[0007] In this scheme, the equally spaced reference objects are most dispersed at the end of the second end, reducing the risk of misidentification due to adjacent reference objects being too close together, thereby improving the accuracy and precision of positioning and reducing surgical risks.

[0008] Preferably, the end of the second end has an outwardly convex curved profile.

[0009] In this procedure, before the stent is released, the second end needs to be placed against the coronary sinus wall outside the coronary ostium. The outwardly protruding curved contour provides a smoother contact, avoiding damage to the coronary sinus wall.

[0010] Preferably, the positioning conduit includes a body and a bend, the bend being formed by bending the end of the positioning conduit outward, and the connection between the bend and the body forming the curved profile of the second end.

[0011] In this design, the structure is designed to bend outwards for easier processing. If it were bent inwards, the bent portion would easily interfere with the internal support. In addition, the connection formed by the bend is smoother and makes it safer to contact the coronary sinus wall.

[0012] Preferably, the end of the bent portion points towards the body.

[0013] In this design, the end of the bend points towards the main body to avoid interference with surrounding tissues and damage, thus improving the applicability of the catheter assembly.

[0014] Preferably, the diameter of the positioning conduit gradually decreases from the second end to the first end.

[0015] In this design, to prevent the positioning catheter from entering the coronary ostium, the diameter of the second end needs to be larger than the opening of the coronary ostium. At the same time, to better position the stent within the catheter assembly, the diameter of the catheter assembly cannot be too large. By setting the diameter to be tapered, the stent can be better positioned during catheter delivery, and the entry of the second end into the coronary ostium can be effectively prevented.

[0016] Preferably, the positioning conduit has a mesh structure.

[0017] In this design, the mesh structure enhances the toughness and strength of the positioning catheter, enabling it to adapt to the complex environment required for surgical procedures without affecting blood flow.

[0018] Preferably, the positioning conduit is made of shape memory alloy;

[0019] In this approach, the positioning catheter can be embedded within the guiding catheter. Once the guiding catheter is aligned with the coronary ostium, the guidewire passes through the coronary lesion segment to the distal end, and the guiding catheter is withdrawn. The positioning catheter is then released and deployed at the appropriate time, ensuring the stability and accuracy of the catheter assembly during stent implantation.

[0020] Preferably, the reference object is visible under X-rays.

[0021] In this design, the structure can be easily observed and located using X-rays, reducing the difficulty of surgical procedures and improving the success rate and safety of the surgery.

[0022] The present invention also discloses a method for releasing a stent, which uses the above-described catheter assembly and includes the following steps:

[0023] Advance the catheter assembly so that the end of the second end contacts the wall of the coronary sinus outside the coronary ostium;

[0024] Adjust the orientation of the imaging machine so that at least three of the aforementioned reference objects are aligned in a line on the imaging machine's image.

[0025] In this approach, the catheter assembly is fixed to the coronary sinus wall outside the coronary ostium, ensuring that the end of the second end is flush with the coronary ostium. By adjusting the direction of the angiography machine, multiple reference points on the angiography machine image are aligned in a straight line. The angiography machine is positioned at the angiographic tangent of the end of the second end, meaning that the angiography machine's viewing angle, the end of the second end of the positioning catheter, and the coronary ostium are all flush. At this point, the stent is delivered and released. By observing the angiography machine, the stent can be accurately released to the coronary ostium, avoiding excessive stent dislodgement or failure to completely cover the coronary ostium, thus ensuring accurate stent positioning.

[0026] Preferably, the positioning catheter is made of shape memory alloy and is built into the guiding catheter. Before the step of advancing the catheter assembly to make the end of the second end contact the coronary sinus wall outside the coronary ostium, the procedure further includes the step of pushing the positioning catheter out of the guiding catheter to fully unfold the positioning catheter.

[0027] In this approach, the positioning catheter is pre-embedded within the guiding catheter and released and deployed at the appropriate time, ensuring the stability and accuracy of the catheter assembly during stent implantation.

[0028] The positive and progressive effects of this invention are as follows: by fixing the catheter assembly to the coronary sinus wall outside the coronary ostium, the end of the second end is flush with the coronary ostium. By adjusting the direction of the angiography machine, the three reference objects on the angiography machine image are aligned in a straight line. The angiography machine is located at the angiography tangent of the end of the second end, that is, the viewing angle of the angiography machine, the end of the second end of the positioning catheter, and the coronary ostium are all flush. At this time, the stent is delivered and released. By observing the angiography machine, the stent can be accurately released to the coronary ostium, avoiding excessive stent dislodgement or failure to completely cover the coronary ostium, thereby accurately positioning the stent. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the catheter assembly according to a preferred embodiment of the present invention.

[0030] Figure 2 This is a schematic diagram of the delivery conduit according to a preferred embodiment of the present invention.

[0031] Figure 3 This is a schematic diagram of the positioning catheter according to a preferred embodiment of the present invention.

[0032] Figure 4 This is a schematic diagram of the end face structure of the positioning catheter according to a preferred embodiment of the present invention.

[0033] Figure 5 This is a schematic diagram of the catheter assembly and angiography machine according to a preferred embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram of the catheter assembly releasing the stent in place according to a preferred embodiment of the present invention.

[0035] Figure 7 This is a flowchart of a stent release method according to a preferred embodiment of the present invention.

[0036] Explanation of reference numerals in the attached figures

[0037] Delivery tube 1

[0038] Output terminal 11

[0039] Positioning catheter 2

[0040] First end 21

[0041] Second end 22

[0042] Reference point 221

[0043] Ontology 23

[0044] Bending section 24

[0045] Bracket 3

[0046] Imaging Machine 4

[0047] Blood vessel 5

[0048] Coronary artery ostium 51

[0049] Guide wire 6 Detailed Implementation

[0050] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments described herein.

[0051] like Figures 1-6As shown, this embodiment discloses a catheter assembly, which includes a delivery catheter 1 for delivering a stent 3. The catheter assembly also includes a positioning catheter 2, which includes a first end 21 and a second end 22. The delivery catheter 1 includes an output end 11 for delivering the stent 3. The first end 21 is connected to the output end 11. The end of the second end 22 is circular, and three reference objects 221 are distributed on the end of the second end 22.

[0052] In this embodiment, by fixing the catheter assembly to the coronary sinus wall outside the coronary ostium 51, the end of the second end 22 is flush with the coronary ostium 51. By adjusting the direction of the angiography machine 4, the three reference objects 221 are aligned on the image of the angiography machine 4. The angiography machine 4 is located at the angiography tangent of the end of the second end 22, that is, the viewing angle of the angiography machine 4, the end of the second end 22 of the positioning catheter 2, and the coronary ostium 51 are flush. At this time, the stent 3 is delivered and released. By observing the angiography machine 4, the stent 3 can be accurately released into the coronary ostium 51, avoiding excessive stent detachment or failure to completely cover the coronary ostium 51, thereby accurately positioning the stent 3.

[0053] Specifically, by setting three reference objects 221 at the end of the second end 22 of the positioning catheter 2, a clear reference line can be formed on the image of the angiography machine 4. During the operation, after fixing the catheter assembly to the coronary sinus wall outside the coronary ostium 51, ensure that the end of the second end 22 is flush with the coronary ostium 51; then, adjust the direction of the angiography machine 4 so that the three reference objects 221 are in a straight line on the image of the angiography machine 4. This requires adjusting the angle and position of the angiography machine 4 to make the reference objects 221 form a clear straight line; when the reference objects 221 are in a straight line, and the angiography machine 4 is located at the second end 22 of the positioning catheter 2, a clear reference line is formed. When the angiography is performed at the two ends, the angiography machine 4, the second end 22 of the positioning catheter 2, and the coronary ostium 51 are aligned. Then, the stent 3 is delivered. By observing the angiography machine 4, the doctor can ensure that the end of the stent 3 is on the straight line formed by the three references 221, indicating that the stent 3 has reached the coronary ostium 51. The doctor can then accurately release the stent 3 into the coronary ostium 51. By using the references 221 on the positioning catheter 2, the doctor can obtain guidance for the accurate placement of the stent 3, ensuring that the stent 3 covers the coronary ostium 51 and avoids deviation. This helps the doctor to achieve more accurate stent 3 positioning during the operation.

[0054] Specifically, in this embodiment, the support 3 is composed of steel beams, which are visible under X-rays.

[0055] Preferably, a reference object is also provided at the end of the stent 3. By observing the angiography machine 4, when the reference object at the end of the stent 3 and the reference object on the positioning catheter 2 are on the same reference line, it indicates that the stent 3 has reached the coronary artery ostium 51, and the stent 3 is released at this time.

[0056] Specifically, the number of reference objects 221 for positioning catheter 2 can be set to more than four as needed.

[0057] Specifically, in this embodiment, the reference object 221 is visible under X-rays. By using X-rays, it can be easily observed and located, reducing the difficulty of surgical procedures and improving the success rate and safety of the surgery. The reference object 221 can be made of high-density heavy atomic elements, such as metals. Of course, in other alternative embodiments, the position of the reference object 221 can also be observed by imaging methods such as ultrasound or nuclear magnetic resonance.

[0058] like Figure 3 As shown, the diameter of the positioning catheter 2 tapers from the second end 22 to the first end 21. To prevent the positioning catheter 2 from entering the coronary ostium 51, the diameter of the end of the second end 22 needs to be larger than the opening of the coronary ostium 51. Simultaneously, to better position the stent 3 within the catheter assembly, the diameter of the catheter assembly cannot be too large. By setting the diameter to taper, both better positioning of the stent 3 during catheter delivery and effective prevention of the end of the second end 22 from entering the coronary ostium 51 can be achieved. Of course, in other alternative embodiments, the diameter of the positioning catheter 2 can be consistent from the second end 22 to the first end 21.

[0059] Specifically, the positioning catheter 2 has a mesh structure. The mesh structure improves the toughness and strength of the positioning catheter 2, enabling it to adapt to the complex environment required for surgical procedures without affecting blood flow.

[0060] Specifically, the positioning catheter 2 is made of shape memory alloy; specifically, it is made of nickel-titanium alloy. Shape memory alloys have a shape memory effect, meaning they can recover their original shape after undergoing plastic deformation. The positioning catheter 2 can be embedded within the guiding catheter (not shown in the figure). After the guiding catheter is aligned with the coronary ostium 51, the guidewire 6 passes through the coronary lesion segment to the distal end, and the guiding catheter is retracted. The positioning catheter 2 is then released and deployed at an appropriate time, ensuring the stability and accuracy of the catheter assembly during stent 3 implantation. Furthermore, the shape memory alloy also possesses superelasticity, allowing for reversible elastic deformation under significant stress without permanent deformation or rupture, thus increasing its reliability and safety.

[0061] Specifically, the conduit assembly is provided with two separate conduits, namely, a positioning conduit and a delivery conduit, which are connected at their ends, that is, the first end 21 is connected to the output end 11. Of course, in other alternative embodiments, the conduit assembly can also be integrally formed, that is, the positioning conduit corresponds to the positioning section of the conduit assembly, and the delivery conduit corresponds to the delivery section of the conduit assembly.

[0062] like Figure 4As shown, the three reference objects 221 are evenly spaced at the end of the second end 22, that is, spaced 120° apart. The evenly spaced reference objects 221 have the highest dispersion at the end of the second end 22, reducing the risk of misidentification due to adjacent reference objects being too close together, thereby improving the accuracy and precision of positioning and reducing surgical risks. Of course, in other alternative embodiments, the reference objects 221 can be distributed at arbitrary intervals.

[0063] like Figure 5 and Figure 6 As shown, the end of the second end 22 has an outwardly convex curved profile. Before releasing the stent 3, the end of the second end 22 needs to abut against the coronary sinus wall outside the coronary ostium 51. The outwardly convex curved profile provides a smoother contact and avoids damage to the coronary sinus wall.

[0064] Specifically, the positioning catheter 2 includes a body 23 and a bend 24. The bend 24 is formed by bending the end of the positioning catheter 2 outward. The connection between the bend 24 and the body 23 forms the curved profile of the second end 22. Bending outward facilitates processing. If bending inward, the bend 24 is prone to interference with the internal stent 3. In addition, the connection formed by bending is smoother and makes contact with the coronary sinus wall safer.

[0065] like Figure 5 and Figure 6 As shown, the end of the bend 24 points towards the body 23. This orientation of the bend 24 towards the body 23 prevents interference with surrounding tissues and thus improves the applicability of the catheter assembly.

[0066] Specifically, in this embodiment, the folding angle of the bending portion 24 is greater than 90°, that is, it is an obtuse folding angle, so as to prevent the steel beam at the farthest end of the second end 22 from damaging the coronary sinus myocardial tissue outside the coronary artery orifice 51. Three reference objects 221 are set on the folding portion of the bending portion 24.

[0067] In other preferred embodiments, the bending angle of the bending portion 24 can be greater than 180°, so that the end of the bending portion 24 is less likely to interfere with other structures.

[0068] Specifically, the maximum diameter of the second end 22 of the positioning catheter 2 is approximately 6 mm, which is larger than the diameter of most human coronary arteries (3-4 mm).

[0069] like Figure 7 As shown, the method for releasing the stent 3 using the above-described catheter assembly in this embodiment includes the following steps:

[0070] Advance the catheter assembly so that the end of the second end 22 contacts the wall of the coronary sinus outside the coronary ostium 51;

[0071] Adjust the orientation of the imaging machine 4 so that the three reference objects 221 are aligned on the image of the imaging machine 4.

[0072] In this embodiment, by fixing the catheter assembly to the coronary sinus wall outside the coronary ostium 51, the end of the second end 22 is flush with the coronary ostium 51. By adjusting the direction of the angiography machine 4, multiple reference objects 221 are aligned in a straight line on the image of the angiography machine 4. The angiography machine 4 is located at the angiography tangent of the end of the second end 22, that is, the viewing angle of the angiography machine 4, the end of the second end 22 of the positioning catheter 2, and the coronary ostium 51 are flush. At this time, the stent 3 is delivered and released. By observing the angiography machine 4, the stent 3 can be accurately released into the coronary ostium 51, avoiding excessive stent detachment or failure to completely cover the coronary ostium 51, thereby accurately positioning the stent 3.

[0073] Specifically, in the initial state, the stent 3 is located inside the catheter assembly, and the stent 3 and the catheter assembly are located inside the guiding catheter (not shown in the figure). First, the guiding catheter is positioned at the coronary ostium 51, and then the guiding catheter is withdrawn, that is, the positioning catheter 2 is pushed out of the guiding catheter, so that the catheter assembly is exposed and unfolded, and then fixed at the coronary ostium 51. The adjustment is made so that the three reference objects 221 are in a straight line on the image of the angiography machine. Then the stent 3 is delivered. When the end of the stent 3 is in the straight line formed by the reference objects 221, the stent 3 is released.

[0074] Specifically, the stent delivery and deployment process is as follows: First, a 0.014-inch guidewire 6 is passed through the stenotic segment of the blood vessel. Initially, the stent is held in place by a deflated balloon (Rapid Exchange Balloon, RX Balloon). The guidewire 6 does not penetrate the entire catheter; instead, it is withdrawn from the balloon sheath at a certain distance proximal to the balloon. Only the portion of the catheter containing the balloon is advanced along the guidewire 6, facilitating rapid catheter replacement. A pressure pump is connected to the proximal end of the balloon, initially operating under negative pressure. Once the stent is positioned, pressure is applied to the pump, causing the contrast agent-mixed fluid within the pump to flow into the balloon, inflating it. Under X-ray, the inflating balloon, carrying the stent, can be seen with the help of the contrast agent within the balloon, ultimately positioning it on the vessel wall. It should be noted that the specific stent delivery and deployment process is existing technology; further details are omitted.

[0075] Specifically, the delivery and release of stent 3 includes the following process: By observing the angiography machine 4, the doctor can ensure that the tip of stent 3 is on the straight line formed by the three reference points 221, indicating that stent 3 has reached the coronary ostium 51. At this point, stent 3 is released. To avoid deviations caused by angle issues, the doctor can accurately release stent 3 to the coronary ostium 51.

[0076] Specifically, the positioning catheter 2 is made of shape memory alloy and is embedded within the guiding catheter. Before the step of advancing the catheter assembly to contact the end of the second end 22 with the coronary sinus wall outside the coronary ostium 51, the procedure further includes: pushing the positioning catheter 2 out of the guiding catheter to fully deploy the positioning catheter 2. By pre-embedding the positioning catheter 2 within the guiding catheter and releasing and deploying it at the appropriate time, the stability and accuracy of the catheter assembly during stent 3 implantation can be ensured.

[0077] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A catheter assembly comprising a delivery catheter for delivering a stent, characterized in that, The catheter assembly further includes a positioning catheter, which has a first end and a second end. The delivery catheter includes an output end that outputs the stent. The first end is connected to the output end. The end of the second end is circular, and at least three reference points are distributed on the end of the second end. At least three of the reference objects are equally spaced at the end of the second end; The end of the second end has an outwardly convex curved profile; The positioning catheter is made of shape memory alloy, and the reference object is visible under X-rays; This ensures that when the direction of the angiography machine is adjusted so that all reference objects are aligned in a straight line on the image, the angiography machine is positioned at the angiography tangent at the second end. The positioning conduit includes a body and a bend, the bend being formed by bending the end of the positioning conduit outward, and the connection between the bend and the body forming the curved profile of the second end.

2. The catheter assembly as claimed in claim 1, characterized in that, The end of the bent portion points towards the body.

3. The catheter assembly as claimed in claim 1, characterized in that, The diameter of the positioning conduit gradually decreases from the second end to the first end.

4. The catheter assembly as claimed in claim 1, characterized in that, The positioning catheter has a mesh structure.

5. The catheter assembly as claimed in claim 2, characterized in that, The bending angle of the bent portion is greater than 180°, and the maximum diameter of the second end of the positioning catheter is 6mm, which is 3mm-4mm larger than the diameter of most human coronary arteries.

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