Proximal release self-expanding peripheral vascular stent delivery system and application method thereofTechnical Field
The invention belongs to the technical field of medical appliances, and particularly relates to a near-end release self-expanding peripheral vascular stent conveying system and a using method thereof.
Background
The self-expanding peripheral vascular stent in clinical application at present is released from the distal end, as shown in fig. 6, the sheath tube is withdrawn to release the stent from the distal end (the proximal end refers to the end which is close to the heart according to the blood flow direction, the distal end refers to the end which is far away from the heart according to the blood flow direction), especially for some lesions which are involved in the vascular opening, the release from the distal end often leads to inaccurate positioning of the lesion position at the proximal end, including insufficient coverage of the lesion segment or overlong lesion, thereby affecting the success rate and treatment effect of the operation, and the long sheath tube is often required to be additionally matched to push contrast agent when the stent is released, so that the lesion position is clear in the operation.
In order to improve the positioning accuracy of the stent, balloon expandable stents are also used clinically. A problem with balloon-expandable stents is that the balloon-expandable stent cannot be repositioned after balloon expansion. And the balloon expandable stent has higher radial strength due to the stent material, the manufacturing process and the like, and the vascular compliance is poorer than that of a self-expanding stent.
There are also some post-stent delivery systems and methods for improving stent positioning accuracy, and stent-grafts employing post-delivery systems are currently used in aortic systems such as the COOK company Zenith TX. The post-release is to open the proximal bare stent anchoring zone after the stent graft body is released, so that the post-anchoring position of the stent at the ideal position can be adjusted to realize more accurate release. However, the peripheral vascular stent has a smaller diameter than the aorta, so that the post-release delivery system and the method with complex designs are not easy to realize on the peripheral vascular stent delivery system with a smaller diameter. Thus, there is a need for a more easily designed delivery system and delivery method that permits adjustment of the proximal position of the stent during delivery of the peripheral vascular stent.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention provides a proximal release self-expanding peripheral vascular stent conveying system and a using method thereof, which can change the release direction of a stent, start release from a proximal end, push contrast agent through a sheath radiography connecting pipe to confirm the lesion position, adjust the stent to a proper position and then release all the stent, thereby ensuring that the stent fully covers a lesion section.
The specific technical scheme is as follows:
A proximal release self-expanding peripheral vascular stent delivery system comprises a delivery sleeve, a stent release protection sleeve, a recovery sleeve, a sheath contrast connecting tube, a stent and a guide wire;
the inner diameter of the conveying sleeve is adapted to the diameter of the guide wire, and can be pushed to a lesion position along the guide wire;
The front end of the conveying sleeve is connected with a support release protection sleeve, the first end of the support release protection sleeve and the front end of the conveying sleeve are integrally arranged, the second end of the support release protection sleeve is turned over and sleeved on the conveying sleeve to form a sleeve-returning section, and the support is fixed in the sleeve-returning section by the support release protection sleeve and is in a compressed state and can be released and opened along with the retraction of the support release protection sleeve;
the recovery sleeve gap is arranged between the conveying sleeve and the outer sheath sleeve, and the bracket is preinstalled at the front end of the recovery sleeve, so that the bracket is integrally arranged between the bracket release protection sleeve and the recovery sleeve when the bracket is not released;
the front end of the outer sheath sleeve and the rear end of the return sleeve section of the support release protection sleeve are arranged at intervals;
the outer sheath radiography connecting pipe is arranged at the tail end of the outer sheath sleeve and is used for pushing and injecting contrast agent.
Further, the support release protection sleeve is made of flexible materials.
Furthermore, the bracket release protection sleeve is made of polyethylene materials and polyurethane materials.
Further, the stent adopts a self-expanding peripheral vascular stent.
Further, the brackets have different specification models.
A method of using a proximal release self-expanding peripheral vascular stent delivery system comprising the steps of:
after the lesion position is preliminarily determined, the guide wire passes through a peripheral vascular lesion section and then is sent into a conveying sleeve, a recovery sleeve and an outer sheath sleeve along the guide wire to reach the lesion position;
Injecting contrast medium into peripheral blood vessel through the tube joint of the sheath contrast connecting tube, and determining the lesion position again to ensure that the proximal end of the stent completely covers the proximal end of the lesion;
And thirdly, withdrawing the conveying sleeve, enabling the stent release protection sleeve to enter the recovery sleeve, gradually withdrawing from the stent, and gradually opening and releasing the stent from the proximal end until the whole stent is completely expanded.
The beneficial effects of the invention are as follows:
The invention can be applied to the interventional therapy of peripheral arterial diseases, so that the design of realizing more convenience can realize the proximal release of the peripheral blood vessel self-expanding stent, and the accuracy of the proximal positioning of the blood vessel is improved. Is especially suitable for the affected part of vascular opening lesions such as renal arteries, superior mesenteric arteries, the branching part of superficial femoral arteries and deep femoral arteries, the part of the puncture access on the side of the iliac artery opening and the like (due to the influence of factors such as hemodynamics and the like, the occurrence rate of stenosis and occlusion at the vascular opening is high, and the patients have larger groups in clinical treatment). Insufficient coverage of the proximal end of the stent can easily lead to failure of treatment or the need to supplement additional stents, and excessive coverage beyond the proximal end can easily affect the aorta or other adjacent vessels, affecting hemodynamic and long term effects. According to the invention, the release direction of the stent is changed, the stent starts to release from the proximal end, after a part of the proximal end of the stent is opened, the contrast medium is injected by pushing through the sheath contrast connecting pipe to confirm the lesion position, and the stent is fully released after being adjusted to a proper position, so that the stent can be ensured to fully cover the lesion section and not exceed the opening. The unsuccessful operation or the increase of complications caused by inaccurate stent release and positioning are reduced.
Drawings
FIG. 1 is a schematic view of a proximal release self-expanding peripheral vascular stent delivery system according to the present invention in a stent compressed state;
FIG. 2 is a schematic diagram of a stent release process of the proximal release self-expanding peripheral vascular stent delivery system of the present invention;
FIG. 3 is a schematic illustration of the fully released stent configuration of the proximal release self-expanding peripheral vascular stent delivery system of the present invention;
FIG. 4 is an enlarged schematic view of a part of the structure of the present invention;
FIG. 5 is a schematic enlarged view of a part of the present invention;
FIG. 6 is a schematic diagram of a conventional self-expanding peripheral arterial stent delivery and release system;
Wherein, 1, a delivery sleeve, 2, a recovery sleeve, 3, a stent release protection sleeve, 4, an outer sheath sleeve, 5, an outer sheath radiography connecting pipe, 6, a stent, 7, a guide wire.
Detailed Description
For better explanation of the present invention, for easy understanding, the technical solution and effects of the present invention will be described in detail below by way of specific embodiments with reference to the accompanying drawings.
In the description of the invention, it will be understood that proximal refers to the end that is closest to the heart in the direction of blood flow, distal refers to the end that is furthest from the heart in the direction of blood flow, axial refers to the direction parallel to the line connecting the distal end of the instrument or member with the center of the proximal end, and radial refers to the direction perpendicular to the axial, and inner and outer are positions defined by the distance from the center of the instrument or member, where inner is the position closest to the center of the instrument or member and outer is the position furthest from the center of the instrument or member. The above description of orientation words is merely for convenience in describing embodiments of the present invention and for simplicity of description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operate in a particular orientation, and therefore should not be construed as limiting embodiments of the present invention.
As shown in fig. 1 to 5, the present embodiment provides a proximal release self-expanding peripheral vascular stent delivery system comprising a delivery sheath 1, a stent release protective sheath 3, a recovery sheath 2, a sheath 4, a sheath contrast connection tube 5 and a stent 6;
The delivery sleeve 1 is pushed to a lesion position along the guide wire 7, the inner diameter of the delivery sleeve 1 is adapted to the diameter of the guide wire 7 (the diameter of the guide wire 7 is 0.035 inch, 0.018 inch in common use), the front end of the delivery sleeve 1 is connected with the stent release protective sleeve 3, the first end of the stent release protective sleeve 3 is integrally arranged with the front end of the delivery sleeve 1, the second end of the stent release protective sleeve 3 is turned over and sleeved on the delivery sleeve 1 to form a sleeve-retracting section, the stent 6 is fixed in the sleeve-retracting section by the stent release protective sleeve 3 and is in a compressed state and can be released and opened along with the retraction of the stent release protective sleeve 3, the stent release protective sleeve 3 can be made of flexible materials with retractile and tensile strength, such as polyethylene materials and polyurethane materials, and can wrap the stent 6 to be in a compressed state so as to smoothly pass through an intravascular stenosis or an occlusion lesion section. The outer sheath sleeve 4 is arranged outside the recovery sleeve 2, the outer sheath sleeve 4 can move relative to the recovery sleeve 2, and the front end of the outer sheath sleeve 4 is arranged at intervals with the rear end of the sheath returning section of the support release protection sleeve 3. The tail end of the sheath sleeve 4 is provided with a sheath radiography connecting pipe 5 so as to push contrast agent through the sheath radiography connecting pipe 5 before releasing the stent 6, display lesion positions in real time and better guide positioning accuracy, the recovery sleeve 2 is arranged between the conveying sleeve 1 and the sheath sleeve 4 in a clearance mode, the recovery sleeve 2 and the conveying sleeve 1 are coaxially designed, the stent 6 is preinstalled at the front end of the recovery sleeve 2, so that the stent 6 is integrally arranged between the stent release protecting sleeve 3 and the recovery sleeve 2 when not released, the recovery sleeve 2 is fixed when the stent is released, the conveying sleeve 1 is retracted, and the stent release protecting sleeve 3 connected with the conveying sleeve 1 can be gradually retracted into the recovery sleeve 2 along the end part of the recovery sleeve 2.
The length and the diameter of the stent 6 can be of different specifications (the diameter of the peripheral blood vessel is 4mm-14mm and the length of the peripheral blood vessel is 20mm-200mm, which are commonly used at present), and the stent 6 is synchronously conveyed along with the movement of the conveying sleeve 1 and the recovery sleeve 2 before the stent is released from the protective sleeve 3.
In the invention, the stent 6 adopts a self-expanding peripheral vascular stent, when the stent 6 reaches a lesion section along with the delivery sleeve 1, the delivery sleeve 2 is fixed, the delivery sleeve 1 is retracted, so that the stent release protection sleeve 3 can be propped against the recovery sleeve 2, and gradually separated from the stent 6 and retracted into the recovery sleeve 2, and the stent 6 is gradually opened and released from the proximal end until the whole stent 6 is completely opened.
The using method of the stent conveying system comprises the following steps:
firstly, initially determining a lesion position by angiography under DSA (subtraction angiography), and after a guide wire 7 passes through a peripheral vascular lesion section, sending the guide wire 7 into a conveying sleeve 1, a recovery sleeve 2 and an outer sheath sleeve 4 to reach the lesion position;
Injecting contrast medium into peripheral blood vessel through the tube joint of the sheath contrast connecting tube 5, and flowing out from the distal end after passing through the inner cavity of the sheath sleeve 4, thereby determining the lesion position again, and enabling the proximal end of the stent 6 to completely cover the proximal end of the lesion;
step three, after the position is adjusted under the perspective, the delivery sleeve 1 is retracted, the stent release protection sleeve 3 enters the recovery sleeve 2, so that the stent 6 is gradually retracted from the stent 6, the stent 6 is gradually opened and released from the proximal end until the whole stent 6 is completely expanded, and then the delivery sleeve 1, the stent release protection sleeve 3, the recovery sleeve 2 and the outer sheath sleeve 4 are completely retracted from the body.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.