Stent delivery device and method for bifurcated blood vessels

Abstract

The present invention discloses a stent delivery device for bifurcated blood vessels and a method thereof, belonging to the field of medical devices. The device includes a delivery tube, a vascular stent, a handle, and a guidewire tube. The delivery tube is an elongated member, and its interior is divided into a main lumen and a secondary lumen by a lumen wall. The main lumen is closed at the distal end by the guidewire tube, and is provided with an outlet hole for the main guidewire to pass through the guidewire tube into its distal end and pass through the vascular stent. The secondary lumen is provided with an outlet less than the distal end. The handle is connected to the proximal end of the delivery tube and communicates with the main lumen. It is provided with a guidewire tube for the secondary guidewire to pass through and extend toward the secondary lumen. The distal end of the delivery tube is provided with a vascular stent and an expander that communicates with the main lumen and is used to expand the vascular stent. The vascular stent has a clearance opening for the secondary guidewire to pass through at a position relative to the outlet of the secondary lumen. The present invention can deliver stents to bifurcated blood vessels and has the advantages of simple structure and easy operation.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and relates to a stent delivery device for a bifurcated blood vessel and a method thereof, which are suitable for use in clinical delivery of blood vessel stents. Background Art

[0002] It is known that stents can be placed within the vascular system using intravascular technology to treat diseased vessels. Known applications of stents include the treatment of stenosis and atherosclerotic lesions in the coronary, peripheral, and cerebral vascular systems. Stents are typically made of materials with a certain strength and flexibility, such as tantalum, medical stainless steel, and nickel-titanium alloys, and are processed using engraving technology to form a tubular network structure that can be left in the human blood vessels for a long time or temporarily. Stents are formed by luminal balloon expansion. Stents are placed in the diseased section and are designed to resist the inner wall of the patient's blood vessel and provide an unobstructed channel for blood flow within the stent lumen.

[0003] However, stents have to face a problem. Stents are usually designed to be straight homogeneous tubes made of biocompatible materials for treating vascular pathology. At the same time, there are bifurcations in blood vessels. If the diseased segment is located near the bifurcation, placing a stent in the main blood vessel may sometimes affect the smooth flow of the bifurcation, causing blockage of the bifurcation. A secondary expansion of the bifurcation is required, and the positioning of the secondary expansion is not easy, which makes the placement of the secondary stent operationally difficult. When the primary and secondary stents are placed overlapping, the inappropriate overlapping position will increase the risk index of complications. There are also many stent designs to overcome these problems associated with bifurcations. Due to the differences in the angles of vascular bifurcations, the adaptability of this special stent is limited. Therefore, it is necessary to design a stent delivery that adapts to vascular bifurcations. Summary of the Invention

[0004] In view of this, the object of the present invention is to provide a bifurcated double-lumen delivery tube for a vascular stent, so as to solve the problem of stent delivery positioning in bifurcated blood vessels and the problem of forked stent placement guidance.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a bifurcated double-lumen delivery tube for a vascular stent, comprising a delivery tube, a vascular stent, a handle and a guidewire tube. The delivery tube is an elongated member having a proximal end, a distal end and a longitudinal axis therebetween, and is characterized in that the interior of the delivery tube is divided into a main lumen and a secondary lumen by a lumen wall. The main lumen is defined by the delivery tube and extends from the proximal end to the distal end and is closed by the guidewire tube at the distal end. The main lumen is provided with an outlet hole for the main guidewire to pass through the guidewire tube at the distal end and out of the vascular stent after passing through the guidewire tube. The secondary lumen is defined by the delivery tube and extends from the proximal end to less than the distal end and is provided with an outlet less than the distal end. The handle is connected to the proximal end of the delivery tube and communicates with the main lumen, and is provided with a guidewire tube for the secondary guidewire to pass through and extend toward the secondary lumen. The vascular stent and an expander communicated with the main lumen and used to expand the vascular stent are provided at the distal end of the delivery tube, and a clearance opening for the secondary guidewire to pass through is left at a relative position of the vascular stent and the expander at the outlet of the secondary lumen.

[0007] Furthermore, the lumen wall comprises a flexible material having an elastic modulus greater than that of the delivery tube material.

[0008] Further, the delivery tube has a uniform outer diameter along its length from the proximal end to the distal end.

[0009] Furthermore, a lumen ratio of the cross-sectional area of the main lumen and the auxiliary lumen to the cross-sectional area of the lumen wall is greater than 90%.

[0010] Furthermore, the expansion member is a capsule.

[0011] Furthermore, the delivery tube is provided with a spiral groove surrounding its outer contour between the outlet of the secondary lumen and the distal end, and the clearance openings provided on the vascular stent and the expansion piece match the spiral groove.

[0012] Furthermore, the vascular stent is prepared by laser cutting or weaving, and the clearance opening provided on the vascular stent is a hollowed-out portion after cutting or weaving.

[0013] The present invention provides a method for delivering a vascular stent to a lesion segment of a bifurcated vessel using the above-mentioned bifurcated vessel stent delivery device, comprising the following steps:

[0014] 1) The vascular stent loaded on the distal end of the delivery tube is advanced along the main guidewire to the bifurcation vascular lesion segment in the blood vessel;

[0015] 2) advancing the auxiliary guide wire through the delivery tube in the auxiliary lumen to the bifurcated blood vessel and coordinating with the delivery tube to position the guide wire;

[0016] 3) Pressurizing the main lumen of the delivery tube to expand the stent via the expansion element at the distal end thereof.

[0017] Preferably, after step 3), the patency of the bifurcated blood vessel is confirmed. If not, the procedure ends. If so, another expansion piece with a control wire is advanced through the secondary lumen of the delivery tube to the bifurcated blood vessel via the secondary guide wire, and then the control wire is pressurized to open the expansion piece, so that the vascular stent expands at the bifurcated blood vessel at the diseased segment of the bifurcated blood vessel.

[0018] Preferably, after step 3), the patency of the bifurcated blood vessel is confirmed. If not, the process ends; if so, another vascular stent with a control wire is advanced through the secondary lumen of the delivery tube to the bifurcated blood vessel through the secondary guide wire, and then the control wire is pressurized to expand the next vascular stent.

[0019] The beneficial effects of the present invention are:

[0020] 1. The present invention can deliver stents to bifurcated blood vessels through a delivery tube, solving the problem of stent delivery in bifurcated blood vessels and having the advantages of simple structure and easy operation.

[0021] 2. The present invention solves the problem of stent delivery positioning in bifurcated blood vessels and the problem of stent placement guidance in bifurcated blood vessels through the combined effect of the delivery tube having dual lumens and the auxiliary guide wire.

[0022] 3. The present invention provides a spiral groove at the distal end of the delivery tube, so that the auxiliary guide wire coming out of the auxiliary lumen rotates along the elongated member, so as to better enter the bifurcated blood vessel and facilitate the delivery of the bifurcated stent.

[0023] Other advantages, objects, and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art upon examination of the following description or may be learned from practice of the present invention. The objects and other advantages of the present invention may be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below with reference to the accompanying drawings, in which:

[0025] Figure 1 This is a schematic structural diagram of the delivery tube of the present invention;

[0026] Figure 2 Schematic diagram of the cross-sectional structure of the delivery tube of the present invention;

[0027] Figure 3 A flow chart for delivering a vascular stent according to the present invention;

[0028] Reference numerals: delivery tube 1 , vascular stent 2 , handle 3 , guidewire tube 4 , guidewire tube 5 , main guidewire 6 , auxiliary guidewire 7 ; main lumen 11 , auxiliary lumen 12 , lumen wall 13 , lead-out hole 14 , outlet 15 , spiral groove 16 . DETAILED DESCRIPTION

[0029] The present invention is further described below with reference to specific embodiments. The accompanying drawings are for illustrative purposes only and are schematic, not actual, representations. They should not be construed as limiting this patent. To better illustrate the embodiments of the present invention, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted from the drawings.

[0030] One or more embodiments of the present disclosure may generally relate to making and using a vascular stent delivery tube or system or other steerable vascular stent. Vascular stent delivery may allow a medical professional to deliver an intravascular or other medical device to a target location within a patient's body.

[0031] Example 1:

[0032] like Figure 1 、 2 The bifurcated vascular stent delivery device in this embodiment includes a delivery tube 1, a vascular stent 2, a guidewire tube 5 and a handle 3, wherein the delivery tube 1 is an elongated member having a proximal end, a distal end and a longitudinal axis therebetween. The delivery tube 1 is divided into a main lumen 11 and a secondary lumen 12 by a lumen wall 13. The main lumen 11 is defined by the delivery tube and extends from the proximal end to the distal end, and is closed by the guidewire tube 5 at its distal end. The main lumen 11 is provided with an outlet hole 14 for the main guidewire 6 to pass through the guidewire tube 5 into its distal end and out of the vascular stent 2. The secondary lumen 12 is defined by the delivery tube and extends from the proximal end to less than the distal end, and is provided with an outlet 15 less than the distal end. The handle 3 is connected to the proximal end of the delivery tube 1 and communicates with the main lumen 11. A guide wire tube 4 is provided on it for the secondary guide wire 7 to penetrate and extend toward the secondary lumen 12. A vascular stent 2 and an expander (not shown) that is communicated with the main lumen 11 and used to expand the vascular stent 2 are provided at the distal end of the delivery tube 1. The expander is a capsule, and the vascular stent 2 and the expander are relative to the outlet 15 of the secondary lumen 12, leaving a makeshift opening (not shown) for the secondary guide wire 7 to pass through.

[0033] like Figure 3 Specifically, the method for delivering a vascular stent to a lesion segment of a bifurcated vessel includes the following steps:

[0034] 1) The stent 2 loaded on the distal end of the delivery tube 1 is advanced into the bifurcation vascular lesion segment in the blood vessel by the main guide wire 6 that has entered the blood vessel in advance. Figure 3 a;

[0035] 2) Through the delivery tube 1, the auxiliary guide wire 7 is advanced in the auxiliary lumen 12 to the bifurcated blood vessel, as shown in FIG. Figure 3 b, and implement positioning at the distal part of the bifurcation vessel, such as Figure 3 c;

[0036] 3) By pressurizing the main lumen 11 of the delivery tube 1, the expansion member on the distal end expands the vascular stent 2, supporting it on the main path of the bifurcated vascular lesion segment, and completing the placement of the stent. Figure 3 d;

[0037] 4) Confirm the patency of the bifurcated blood vessel. If not, the procedure ends. If patency is confirmed, another stent or expansion member (not shown) with a control wire (not shown) is advanced through the auxiliary guide wire 7 in the auxiliary lumen 12 of the delivery tube 1 to the bifurcated blood vessel. The control wire is then pressurized to expand the stent. Figure 3 e, or dilate the side hole of the bifurcated vessel corresponding to the previous vascular stent at the fork, such as Figure 3 f.

[0038] By adopting the above method, if the diseased segment is located near the bifurcation vessel, a stent is placed in the main vessel, and the stent can be positioned and delivered at the diseased segment of the bifurcation vessel. At the same time, if the bifurcation vessel is blocked, a secondary expansion of the bifurcation can be performed, and the positioning of the secondary expansion can be reliable and accurate. The placement of the secondary stent is also convenient and quick in operation. The primary and secondary stents can be placed on the distal side of the bifurcation vessel when they are overlapped, leaving enough space in the proximal part to facilitate the expansion of the primary stent during the expansion of the secondary stent, reducing the risk index of complications caused by the inappropriate overlapping placement of the two.

[0039] This delivery method is used to treat bifurcated vascular aneurysms or arterial occlusions.

[0040] The lumen wall 13 in this embodiment is made of a flexible material with a larger elastic modulus than the material of the delivery tube 1. The flexible lumen wall with a large elastic modulus allows the main lumen to be pressurized or the secondary lumen to be expanded or even covered to the opposite side when a guide wire or control wire is inserted, thereby facilitating pressurization or entry of a guide wire or control wire without increasing the diameter of the elongated member.

[0041] The delivery tube 1 in this embodiment has a uniform outer diameter along its length from the proximal end to the distal end. The lumen ratio of the cross-sectional area of the main lumen 11 and the secondary lumen 12 to the cross-sectional area of the lumen wall 13 is greater than 90%. Of course, in different embodiments, the distal diameter can be smaller than the proximal diameter.

[0042] Example 2:

[0043] This embodiment differs from the first embodiment in that a spiral groove 16 is provided between the outlet of the secondary lumen 12 and the distal end of the delivery tube 1, encircling the outer contour of the delivery tube 1. Because the longer the delivery tube is within the vessel, the more difficult it is to turn distally, and the direction and angle of the bifurcation at the vascular lesion are not fixed, the outlet of the secondary lumen at the distal end will not correspond to the bifurcation, making it difficult to deliver the stent to the bifurcation. However, the present spiral groove design allows the secondary guidewire exiting the distal outlet of the secondary lumen to be guided by the spiral groove and the inner wall of the vessel, spiraling forward and entering the bifurcation, facilitating stent delivery.

[0044] Preferably, the spiral groove around the delivery tube can be between half a circle and one and a half circles corresponding to the head and tail, and the spiral angle is designed and determined according to the diameter of the auxiliary guide wire and the delivery tube, so as to avoid bending the front end of the auxiliary guide wire and affecting its entry into the bifurcated blood vessel without affecting the spiral advancement of the auxiliary guide wire in the auxiliary tube cavity.

[0045] Correspondingly, the clearance openings provided on the vascular stent 2 and the expansion piece match the spiral groove 16, so as not to affect the passage of the auxiliary guide wire.

[0046] The vascular stent 2 in this embodiment is prepared by laser cutting or weaving, and the clearance opening provided on the vascular stent 2 is a hollowed-out portion after cutting or weaving.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions, which should all be included in the scope of the claims of the present invention.

Claims

1. A bifurcated vascular stent delivery device comprising a delivery tube (1), a vascular stent (2), a handle (3) and a guidewire tube (5), wherein the delivery tube is an elongated member having a proximal end, a distal end and a longitudinal axis therebetween, and wherein: The delivery tube is divided into a main lumen (11) and a secondary lumen (12) by a lumen wall (13). The main lumen is defined by the delivery tube and extends from the proximal end to the distal end, and is closed by the guide wire tube at its distal end. The main lumen is provided with an outlet (14) for the main guide wire (6) to pass through the guide wire tube into its distal end and pass through the vascular stent. The secondary lumen is defined by the delivery tube and extends from the proximal end to less than the distal end, and is provided with an outlet (15) less than the distal end. The handle is connected to the proximal end of the delivery tube and communicates with the main lumen. A guide wire tube (4) is provided on the handle for the secondary guide wire (7) to pass through and extend toward the secondary lumen. A vascular stent and an expansion member communicated with the main lumen and used to expand the vascular stent are provided at the distal end of the delivery tube, and a clearance opening for the secondary guide wire to pass through is left at the relative position of the vascular stent and the expansion member at the outlet of the secondary lumen. The delivery tube is provided with a spiral groove (16) surrounding its outer contour between the outlet of the secondary lumen and the distal end, and the clearance openings provided on the vascular stent and the expansion piece match the spiral groove; The delivery tube has a uniform outer diameter along its length from the proximal end to the distal end.

2. The bifurcated blood vessel stent delivery device according to claim 1, wherein: The lumen wall is a flexible material having a modulus of elasticity greater than the modulus of elasticity of the delivery tube material.

3. The stent delivery device for a bifurcated blood vessel according to claim 1, wherein: The lumen ratio of the cross-sectional area of the main lumen and the secondary lumen to the cross-sectional area of the lumen wall is greater than 90%.

4. The stent delivery device for a bifurcated blood vessel according to claim 1, wherein: The expansion member is a balloon.

5. The stent delivery device for a bifurcated blood vessel according to claim 1, wherein: The vascular stent is prepared by laser cutting or weaving, and the clearance opening provided on the vascular stent is a hollowed-out portion after cutting or weaving.

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