CN115670762A - In-situ windowing instrument capable of puncturing covered stent vertically - Google Patents

Abstract

The invention relates to an in-situ windowing instrument capable of vertically puncturing a covered stent, which is suitable for vertically puncturing the covered stent for windowing at a branch blood vessel in a body, and comprises: a hand-held assembly located proximal to the in situ fenestration instrument; a delivery assembly connected to the distal end of the hand-held assembly, comprising a delivery sheath and an internal push rod; and a puncture assembly connected to the delivery assembly, including a puncture needle connected to the distal end of the push-in pushrod and a plurality of positioning struts secured to the outside of the distal end of the delivery sheath. Thus, an in situ windowing instrument that is more anatomically compliant to the human anatomy and that can vertically puncture a stent graft is provided.

Description

In-situ windowing instrument capable of vertically puncturing covered stent

Technical Field

The invention relates to the technical field of medical instruments, in particular to an in-situ windowing instrument capable of vertically puncturing the surface of a covered stent, and aims to solve the problem that the existing windowing instrument easily and directly damages a branch vessel or an aortic wall in the puncturing process.

Background

With the increasing of the life-span of people in China, the incidence rate of cardiovascular diseases is increasing, and more patients suffering from aortic arch diseases are available. Aortic aneurysms and aortic dissections are a serious, potentially life-threatening aortic arch disease. When a hemangioma or dissection develops, the vessel wall thins, which if not handled in time, can lead to vessel rupture at any time. At present, the aortic aneurysm and aortic dissection are mainly treated by two modes of surgical open surgery and intracavity repair therapy, and compared with the intracavity repair therapy of the surgical open surgery, the aortic aneurysm and aortic dissection has the advantages of small trauma, less bleeding, quick recovery and low mortality. The aortic aneurysm is most commonly found in the thoracic aorta and the abdominal aorta, and when the thoracic aortic aneurysm occurs at or near a multi-branch blood vessel, most patients can only choose open surgery because the blood flow of the branch blood vessel is blocked when the stent graft is used for treatment. Therefore, when aortic disease occurs at or near a multi-branch vessel, it is necessary to open a window at a site on the stent graft corresponding to the branch vessel.

At present, the means for treating aortic arch lesion in a full cavity mainly comprises a pre-windowing technology, a chimney technology, a branch stent technology and an in-situ windowing technology, and the in-situ windowing technology becomes an ideal method due to the following problems:

1. pre-windowing: windowing the corresponding position of the existing commercial finished stent graft in vitro according to the radiography condition of a patient to form a window, and then implanting the window into the pathological change position of an aortic arch. This process will damage the normal structure of the stent, resulting in poor stability of the long term stent. In addition, the window position needs to be aligned with the opening of the branch artery in the circumferential direction and the axial direction and released in the operation, so that the windowing position of the stent covering film is opposite to the branch artery to complete reconstruction, and the process requires an operator to accurately measure the caliber of the proximal anchoring area and the position and the size of the branch blood vessel before the operation. The method has high operation difficulty and accurate alignment difficulty, is easy to cover the branch opening on the arch to cause serious complications, and is difficult to popularize and implement.

2. The chimney technique is that after the aortic arch part releases the main covered stent, the branch covered stent is released through a guide wire reserved in a branch artery, the front half part of the branch stent needs to be placed in parallel with the main stent, and the rear half part of the branch stent is positioned in the branch artery. Because the main body stent and the branch stent are mutually extruded in the tube wall and cannot be tightly attached, the method causes higher risks of internal leakage (blood continuously flows into a lesion area along a parallel gap of the main body stent and the branch stent), aortic tube wall injury and branch stent occlusion;

3. the branch stent technology is that the main stent is designed with branches, and the branch artery can be reconstructed at the same time. But the existing single branch stent is difficult to adapt to reconstruction of 2 or 3 branch vessels on the arch; the existing double-branch stent can reconstruct a brachiocephalic artery and a left common carotid artery at the same time, but can not directly reconstruct a left subclavian artery, needs a hybrid operation to reconstruct the left subclavian artery, and still has larger trauma; at present, no commercial 3-branch stent is available, the finished 3 branches are difficult to be suitable for different vessel anatomies, and the customized 3 branches need to wait for a long time; research reports also show that the incidence rate of cerebral apoplexy is higher in the branch stent technology.

Therefore, the technology is difficult to provide a proper tool for clinically completing the intracavity treatment of aortic arch diseases, the in-situ windowing technology uses the existing commercialized thoracic aorta covered stent, the fenestration instrument (a puncture catheter, a radio frequency catheter or a laser catheter) is used for reversely windowing the aortic stent from the approach of the branch vessel of a patient, the branch vessel on the arch is reconstructed, 1-3 branch vessels on the arch can be reconstructed in the cavity according to needs, the original anatomy is not changed, the accurate alignment is not needed when the main stent is released, the existing commercialized stent is not needed to be customized, and the popularization is easy.

At present, a windowing device used in an existing in-situ windowing technology, for example, a stent graft windowing device mentioned in the invention patent with the application number of 201610507735.2, a guiding device of the windowing device comprises a windowing device with an adjustable bent sheath and a windowing device with an expansion piece arranged at the tip of a puncture piece, although puncture of the stent graft can be achieved to a certain extent, the structure of the windowing device is complex, and the adjustable bent sheath can only achieve horizontal angle adjustment of 0-180 degrees on the same plane but cannot achieve rotation adjustment of 360 degrees, so that certain difficulty is brought to an operator in accurately finding a windowing position when the windowing device is used. The invention patent application No. 202023106404.9 discloses an in-situ fenestration device, which includes an expanding element in a self-expanding configuration, wherein the distal end of the expanding element is fixed on a sheath core tube, and the proximal end of the expanding element is fixedly connected with a sleeve. This expansion piece can support to the window that the tectorial membrane support pierces through the tectorial membrane after carrying out the pjncture needle and pierce through the tectorial membrane of tectorial membrane support, and this kind of structural design has following not enoughly: since the stent is arranged with a low degree of coaxiality with the branch vessel, it is difficult to ensure that the puncture needle is perpendicular to the stent graft during the subsequent puncture operation, which is liable to cause the risk of puncturing the branch vessel and the aortic wall during the puncture, and the tip of the puncture element is connected to the stent and is located at the distal end of the stent in a considerable length, which disadvantageously entails the following risks: when the fenestration of expanding piece to the covered stent is further expanded, the puncture piece that is located the expanding piece distal end can enter into covered stent's inside along with the distal end of expanding piece deepening more, and the another side tectorial membrane and the vascular wall that correspond are opened the window to the covered stent can be punctured to some misoperation then, and have certain potential danger.

Based on this, relevant technical personnel aim at designing an in situ windowing device capable of vertically puncturing the covered stent so as to overcome the defects existing in the prior art, so as to solve the problem that the existing in situ windowing device easily and directly damages a branch blood vessel or an aorta wall in the puncturing process, and when aortic diseases occur at or close to the multi-branch blood vessel, the covered stent can be effectively applied.

Disclosure of Invention

Accordingly, it is an object of the present invention to provide an in situ windowing instrument that can vertically puncture a stent graft, thereby overcoming the disadvantages of the prior art described above.

To accomplish the above object, the present invention provides an in situ fenestration apparatus for vertically puncturing a stent graft, which is adapted to vertically puncture the stent graft at a branch vessel in a body for fenestration, comprising: a hand-held assembly located proximal to the in situ fenestration instrument, configured to allow the in situ fenestration instrument to be held and manipulated; a delivery assembly connected to a distal end of the handpiece assembly, comprising a delivery sheath connected to the handpiece assembly and an internally pushing ram coaxially axially movable within the delivery sheath; and a puncture assembly connected to the delivery assembly, comprising a puncture needle connected to the distal end of the push-in rod and a plurality of positioning struts fixed to the outside of the distal end of the delivery sheath, wherein the plurality of positioning struts can be transformed from a collapsed state to an expanded state when the delivery assembly is guided to the ostium of the branch vessel by means of the guide catheter, so as to vertically position the delivery sheath relative to the stent graft and thereby allow the puncture needle to be pushed out through the push-in rod to vertically puncture the stent graft for fenestration.

Therefore, the invention is different from the prior art, and the puncture needle and the positioning supporting feet are mutually independent by arranging the plurality of positioning supporting feet capable of self-expanding at the outer side of the far end of the conveying sheath pipe provided with the puncture needle. Therefore, on one hand, the positioning supporting foot is arranged at the far end of the conveying sheath, so that the positioning supporting foot and the branch blood vessel are ensured to have reliable coaxiality, and the precision of the vertical puncture windowing is further ensured; on the other hand, when the fenestration operation is performed, the positioning strut is sandwiched between the stent graft and the blood vessel prior to the puncture needle, and then the fenestration operation is performed on the stent graft by the puncture needle. The location spike can not move towards the distal side along with the pjncture needle from this, has confirmed the outer wall position of covered stent through the position of spike to can regard as the benchmark with the help of the spike to confirm the degree of depth that the pjncture needle punctures covered stent, consequently can avoid the pjncture needle to excessively stretch into to covered stent inside stabbing contralateral blood vessel. In short, according to the in-situ windowing instrument disclosed by the invention, the positioning supporting foot can be stably and vertically abutted against the surface of the covered stent, so that the puncture needle can accurately puncture the covered stent, the problem that the existing in-situ windowing instrument easily and directly damages a branch blood vessel or an aorta wall in the puncture process is solved, and when an aortic disease occurs at or close to the multi-branch blood vessel, the effective application of the covered stent can be realized.

In a preferred embodiment, the delivery assembly further comprises a tear-off protective loading tube capable of fitting over the outside of the delivery sheath and configured to constrain expansion of the plurality of positioning struts by its inner wall to maintain the plurality of positioning struts in a collapsed state and to allow removal of the delivery sheath and the plurality of positioning struts therefrom when secured at the exit of the vascular sheath, thereby releasing the constraint on the positioning struts to transition to an expanded state. Thereby, it is ensured in a simple and cost-effective manner that the positioning struts of the in situ window opening device are kept in a folded state for the storage and transport of the device.

In a preferred embodiment, the positioning brace is made of a shape memory metal, preferably nitinol, which preferably includes 3 to 6 tentacles arranged substantially uniformly along the circumference of the delivery sheath. Thereby, a good conformity of the positioning foot with the branch vessel can be ensured to ensure coaxiality with the branch vessel.

In a preferred embodiment, the surface of the positioning foot is provided with a developer coating, preferably applied electrochemically, by spraying or by adhesively riveting. Therefore, the placing position and the state of the positioning supporting foot can be simply determined in the operation process.

In a preferred embodiment, the puncture needle and the push-in plunger are each designed as hollow tubes with a guide wire lumen for the guide wire to pass through, wherein the guide wire lumen is designed to accommodate a maximum of 0.035 inches of guide wire. Thereby, the applicability of the in-situ windowing instrument can be improved.

In a preferred embodiment, wherein the delivery assembly is sized to be placed within a sheath having a tube diameter in the range of 4Fr and 6 Fr. Thereby, the versatility of the in situ windowing tool can be improved.

In a preferred embodiment, the handle assembly includes a puncture button disposed on the handle body, wherein the push-in plunger is coupled to the puncture button for moving the push-in plunger and the puncture needle distally relative to the delivery sheath when the puncture button is moved distally relative to the handle body.

In a preferred embodiment, the hand-held assembly further comprises a Y-catheter hub disposed distal to the handle body and connected to the proximal end of the delivery sheath, wherein the Y-catheter hub is provided with a catheter lumen for holding the delivery sheath and for passing the pusher rod therethrough and a delivery port for delivering the contrast agent.

In a preferred embodiment, the hand-held assembly further comprises a strain relief tube located distally of the handle body, wherein a proximal side of the strain relief tube is connected to the Y-catheter hub.

In a preferred embodiment, the handle body is internally provided with a groove for fixing the Y-shaped catheter seat and the puncture button and a slideway for the puncture button to slide back and forth along the handle body.

In a preferred embodiment, the needle extends from the distal end of the delivery sheath by a length in the range of 1 to 25 mm. Thereby, it is ensured that the puncture needle does not extend improperly to the other side of the stent graft and erroneously penetrate the stent graft.

In a preferred embodiment, the tip of the needle carries a visualization marker. Therefore, an operator can clearly confirm the position of the puncture needle and the depth of puncturing the covered stent in the operation process, and the puncture needle can be prevented from excessively extending into the covered stent to puncture the opposite side blood vessel.

Additional features and advantages of the invention will be set forth in part in the description which follows, and in part will be apparent to those having ordinary skill in the art upon examination of the following, or may be learned from the practice of the invention.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a front view of the overall structure of an in situ window opening apparatus in an embodiment of the present invention;

FIG. 2 is a side view of the overall structure of an in situ window opening apparatus in accordance with an embodiment of the present invention;

FIG. 3 is a schematic view of the retraction of the spike assembly into the delivery assembly prior to windowing in accordance with an embodiment of the present invention;

FIG. 4 is a schematic view of the puncture assembly extending through the protective loading tube and into the guide catheter, in accordance with an embodiment of the present invention;

FIG. 5 is a schematic view of the positioning foot of the spike assembly extending out of the guide catheter in accordance with an embodiment of the present invention;

FIG. 6 is a schematic view of the positioning strut of the spike assembly extending out of the guide catheter and the spike extending out of the delivery sheath in accordance with an embodiment of the present invention;

FIG. 7 is an enlarged partial view of the positioning brace of the in situ fenestration device puncture assembly entering the aortic arch extension guide catheter in accordance with an embodiment of the present invention;

FIG. 8 is an enlarged schematic view of a positioning arm brace of the puncturing assembly of the in-situ fenestration instrument in an embodiment of the invention shown in the drawing, after entering the aortic arch and being in an open state, and simultaneously retracting the catheter and the in-situ fenestration instrument, so that the positioning arm brace is supported at the branch vessel ostium;

FIG. 9 is a partially enlarged view illustrating the puncture needle penetrating the stent graft during the puncturing operation of the in-situ windowing instrument according to the embodiment of the invention.

Fig. 10 is an enlarged view of a portion of the in situ fenestration device of the embodiment of the invention after the puncture procedure, which allows the puncture needle to be retracted into the guide catheter.

Figure 11 is a top view of a needle in an embodiment of the present invention.

Description of the reference numerals

10-in-situ windowing appliance 1-1-puncture needle 1-2-positioning supporting leg

2-1-protection loading tube 2-2-conveying sheath tube 2-3-inner pushing push rod

3-1-Y type conduit 3-2-stress relief tube 3-3-puncture button 3-4-handle body

A-guide wire H-guide catheter B-tectorial stent

Detailed Description

Reference is now made to the drawings for a detailed description of an exemplary version of a vertically-puncturable stent graft in situ fenestration apparatus in accordance with the invention. The drawings are provided to present embodiments of the invention, but the drawings are not necessarily to scale of the particular embodiments, and certain features may be exaggerated, removed, or partially sectioned to better illustrate and explain the present disclosure. The position of some components in the drawings can be adjusted according to actual requirements on the premise of not influencing the technical effect. The appearances of the phrase "in the drawings" or similar language in the specification are not necessarily referring to all of the drawings or the examples.

Certain directional terms used hereinafter to describe the drawings, such as "inner", "outer", "upper", "lower", "top", "bottom", and other directional terms, will be understood to have their normal meaning and refer to those directions as they relate to when viewing the drawings. Unless otherwise indicated, the directional terms described herein are generally in accordance with conventional directions as understood by those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the field of stent grafts, the end of the blood flow entering the blood vessel or the end near the operator during the operation is generally referred to as the "proximal end" or the "proximal side", the end of the blood flow exiting the blood vessel or the end far from the operator during the operation is referred to as the "distal end" or the "distal side" of the stent, and the "proximal end" and the "distal end" of any component of the in situ fenestration apparatus are defined according to this principle. "axial" generally refers to the length of the catheter or sheath as it is being delivered, and "radial" generally refers to the direction of the catheter or sheath perpendicular to its "axial" direction or parallel to the line joining the centers of the distal and proximal ends of the medical device, and defines both "axial" and "radial" directions for any component of the in situ fenestration device in accordance with this principle. The folding state is the structure when the components such as the positioning supporting legs and the like are contained in the components such as the sheath tube and the like and are compressed in the conveying process; the "expanded state" refers to a structure in which the positioning brace in the folded state is self-expanded and unfolded without being bound by a sheath or the like.

Some embodiments of the invention are described in detail below with reference to the accompanying drawings. The embodiments and features of the embodiments described below can be combined with each other without conflict.

Referring first to fig. 1-2, an in-situ windowing device 10 capable of puncturing a covered stent vertically according to a preferred embodiment of the present invention is shown, wherein the in-situ windowing device 10 capable of puncturing a covered stent vertically can be stably and vertically abutted against the surface of the covered stent by means of a positioning support foot, so that a puncture needle can accurately puncture the covered stent, the problems that an existing in-situ windowing device is easy to directly damage a branch vessel or an aorta wall and penetrate the covered stent during a puncturing process are solved, and when an aortic disease occurs at or near a multi-branch vessel, effective application of the covered stent can be achieved.

As shown in fig. 1-2, the in-situ fenestration apparatus 10 according to the present invention comprises a hand-held assembly, a delivery assembly and a puncture assembly coaxially sleeved in sequence: the delivery assembly is here sleeved on the outside of the puncture assembly and then connected to the hand-held assembly. The three components may be assembled together by a physician or a user before performing a surgical operation, may be simply assembled together at the time of shipment but not fixedly connected to each other, or may be fixedly connected or detachably connected together at the time of shipment, and all of the above modifications are within the scope of the present invention.

Shown on the far right side of fig. 1 is a hand held assembly located proximal to the in situ fenestration instrument 10, which is configured to allow the in situ fenestration instrument 10 to be held and manipulated. The hand-held assembly here comprises a generally cylindrical body designed to be held by a physician or user. The shape of the handle body is set according to actual needs, and is generally a cylindrical structure, but the shape is not limited to the cylindrical structure, so long as the handle body accords with human engineering and is convenient to hold and operate. The practical length of the handle body in the embodiment can be designed to be 8-12 cm, the outer diameter size is 1.5-2 cm, and the handle body is suitable for being held by an operator and accords with the ergonomics.

Above the handle body a puncture button 3-3 is arranged, which can be fixedly connected, e.g. adhesively, to an in-push rod 2-3 in the delivery assembly described below, so that the in-push rod 2-3 and the puncture needle 1-1 are driven to axially project distally relative to the delivery sheath 2-2 when the puncture button 3-3 is moved distally relative to the handle body. In order to allow the push button 3-3 to be moved back and forth in the distal and proximal direction relative to the handle body, the handle body is further provided with a slide for sliding the push button 3-3 back and forth along the handle body, wherein the push button 3-3 is provided with a slide which can be slidably engaged with the slide. Here, the sliding member may be made of metal or polymer material, and the shape of the sliding member may not be limited, but is preferably a long bar-shaped structure or a column-shaped structure so that a length of the protrusion is preferably provided on the sliding member. To engage with a slide having a corresponding recess and thereby co-operate to limit the sliding direction of the slider and its fixedly attached piercing button 3-3. The sliding piece is placed in the slideway and is in plane contact with the bottom of the slideway. Of course, the provision of a slide and slide cooperating in this case for axial movement of the piercing button 3-3 is only an example, and controlled axial movement of the piercing button 3-3 by means of a screw drive or worm gear drive is likewise possible and will not be described in further detail here.

Further, a Y-shaped catheter holder 3-1 connected with a delivery sheath 2-2 is arranged at the far side of the handle body, wherein the Y-shaped catheter holder 3-1 is provided with a catheter cavity for fixing the delivery sheath 2-2 and allowing the push-in rod 2-3 to pass through and a delivery port for delivering contrast medium during operation, and a sealing member for preventing blood from flowing back and overflowing is arranged at the near side of the Y-shaped catheter holder 3-1. Further, the handpiece assembly includes a strain relief tube 3-2 located distally of the handle body, wherein the proximal side of the strain relief tube 3-2 is attached, such as but not limited to, adhesively attached, to the distal nozzle of the Y-catheter hub.

Next, as shown in connection with FIGS. 1-4, a delivery assembly according to the present invention is attached to the distal end of the hand held assembly, and more particularly is preferably adhesively attached to the Y-shaped catheter hub 3-1 of the hand held assembly through a strain relief tube 3-2. Wherein the delivery assembly comprises a tearable protective loading tube 2-1, a delivery sheath 2-2 and an inner push rod 2-3 coaxially axially movable within the delivery sheath 2-2, nested radially in sequence, wherein the delivery assembly is preferably dimensioned for placement within sheaths having a tube diameter in the range of 4 french and 6 french. As shown in fig. 3 herein, the in situ fenestration apparatus 10 further comprises a puncture assembly connected to a delivery assembly, which comprises a puncture needle 1-1 connected to the distal end of an internal push rod 2-3 and a plurality of positioning struts 1-2 fixed to the outside of the distal end of the delivery sheath 2-2, wherein the positioning struts 1-2 are transformable from a collapsed state to an expanded state when the delivery assembly is guided to the ostium of a branch vessel by means of a guiding catheter H as described in detail below, to vertically position the delivery sheath 2-2 relative to the stent graft as described in detail below and thereby allow the puncture needle 1-1 to be pushed out through the internal push rod 2-3 to vertically puncture the stent graft for fenestration.

Specifically, as shown in fig. 3, when the in situ fenestration device 10 is not inside the guiding catheter H, the delivery assembly and the puncture assembly coaxially located therein are both enclosed within the tearable protective loading tube 2-1. In particular, the plurality of positioning struts 1-2 located outside the distal end of the delivery sheath 2-2 abut against the inner wall of the tearable protective loading tube 2-1 in a manner with a certain prestress so that the outward expansion thereof is restrained by the tearable protective loading tube 2-1, which ensures in a simple and user-friendly manner that the positioning struts of the in situ fenestration instrument remain in a collapsed state for the storage and transport of the instrument. The puncture needle 1-1 and the push-in pusher 2-3 are designed as hollow tubular structures with guide wire cavities for the guide wires A to pass through, wherein the guide wire cavities are designed to accommodate the guide wires A of 0.035 inch at most, the guide wires A pass through the whole in-situ fenestration device 10 and then guide the delivery assembly through the vascular system of the human body to enable the delivery assembly to enter the opening position of the predetermined branch vessel along the guide wires A, and at the moment, the positioning support feet 1-2 are also contracted and not expanded in the protective loading tube 2-1. The tearable protective loading tube 2-1 is then guided near the port of the guiding catheter H.

Next, as shown in fig. 3 and 4, the physician or the user can push the handle body to advance the delivery sheath 2-2 relative to the guiding catheter H, which enables the plurality of positioning struts 1-2 fixed to the outside of the distal end of the delivery sheath 2-2 to be released from the inner wall of the tearable protective loading tube 2-1 and to be held in a collapsed state by abutting against the inner wall of the guiding catheter H, since the tearable protective loading tube 2-1 is now arranged immovably relative to the guiding catheter H. This allows the in situ fenestration instrument to then continue to advance the delivery sheath 2-2 distally relative to the guiding catheter H until it is guided to the ostium of the branch vessel. At this time, as clearly shown in fig. 4 to 6, since the positioning struts 1-2 can be released from the inner wall of the guiding catheter H and transformed from the collapsed state to the expanded state and thereby vertically position the delivery sheath 2-2 with respect to the stent graft (clearly shown in fig. 7 to 9). Wherein fig. 7 is a partially enlarged schematic view of the positioning struts 1-2 extending out of the guiding catheter into the aortic arch and fig. 8 is a view showing the positioning struts 1-2 extending out of the guiding catheter H into the aortic arch while withdrawing the guiding catheter H and the handle body to support the positioning struts 1-2 at the ostium of the branch vessel and make room for implanting the stent graft B in the aortic arch. Preferably, the positioning supporting legs are made of shape memory metal, preferably nickel-titanium alloy, and the memory property of the positioning supporting legs is utilized to ensure that the plurality of supporting legs 1-2 still keep an open state when the plurality of supporting legs penetrate out through the distal port of the delivery sheath 2-2.

In order to be able to ascertain with accuracy that the positioning foot 1-1 has been released from the inner wall of the guide catheter H in the branching vessel as shown in fig. 7 and has been brought from the collapsed state into the expanded state, the surface of the positioning foot is preferably provided with a contrast coating which is preferably applied electrochemically, by spraying or by adhesive riveting. Therefore, the placing position and the posture of the positioning supporting foot can be determined simply and quickly in the operation process. In order to introduce a contrast agent for visualizing the position and posture of the positioning foot 1-2 in the body, a certain radial gap is maintained between the push-in rod 2-3 and the delivery sheath 2-2, which is in fluid communication with the delivery port of the Y-shaped catheter hub 3-1, thereby allowing a physician or operator to easily introduce the contrast agent during the operation. Preferably, the plurality of struts of the positioning struts 1-2 each carry a visualization point, while an implantation depth marker band is preferably provided at the proximal end of the delivery sheath to respectively indicate the implantation position and depth of the in situ fenestration instrument within the blood vessel. After passing through the location of the positioning strut 1-2 (as shown in fig. 7), which is visualized by, for example, a contrast agent introduced via the Y-shaped catheter hub 3-1, indicating that the puncture assembly has been guided to the aortic arch via the guide catheter H, the physician or operator retracts the guide catheter H and the handle body 3-4 to support the positioning strut 1-2 at the ostium of the branch vessel, and then may implant a stent graft B (as shown in fig. 8) into the aortic arch. The plurality of positioning struts 1-2 may then be securely sandwiched between the stent graft B and the tissue surface of the ostium of the branch vessel after the stent graft B has been properly positioned, such secure sandwiching via the plurality of positioning struts ensures that the puncture needle perpendicularly pierces the stent graft. Here, it is preferred to include 3 to 6 positioning struts arranged substantially uniformly along the circumference of the delivery sheath, which ensures good conformity of the positioning struts with the branch vessel to ensure coaxiality with the branch vessel.

As shown in FIGS. 8 and 9, after the physician or operator has released the stent graft B to a desired location within the aortic arch and has caused the delivery sheath to be securely positioned vertically relative to the stent graft B with reference to the stent graft by means of the plurality of positioning struts 1-2, the physician or operator may push the puncture button 3-3 to cause an internal push rod 2-3 fixedly connected to the puncture button 3-3 to move distally relative to the delivery sheath 2-2, which in turn causes the puncture needle 1-1 to extend forwardly, causing the puncture needle 1-1 to puncture the stent graft of the stent graft B. Here, as a preferred embodiment, the protrusion length of the puncture needle 1-1 from the distal end port of the delivery sheath 2-2 is in the range of 1 to 25 mm, which prevents the puncture needle 1-1 from being unduly elongated to the other side of the stent graft and erroneously penetrating the stent graft while ensuring a reliable windowing operation. Preferably, the puncture needle 1-1 has a developing mark at its tip. Therefore, an operator can clearly confirm the position of the puncture needle and the depth of puncturing the covered stent in the operation process, and the puncture needle can be prevented from excessively extending into the covered stent to puncture the opposite side blood vessel. As an example, the visualization mark of the tip may be, for example, a ring of X-ray opaque ring provided around the circumferential side of the puncture needle.

Next, as shown in FIG. 10, after the puncture needle 1-1 punctures the stent graft B, the physician or operator can reversely push the puncture button 3-3 back to cause the push-in rod 2-3 to perform a proximal restoring motion relative to the delivery sheath 2-2, which causes the puncture needle 1-1 to retract into the delivery sheath 2-2, and then move the handle body 3-4 proximally relative to the guiding catheter H to retract the plurality of contact pins of the positioning support 1-2 into the guiding catheter H, and finally withdraw the entire in-situ fenestration device 10 out of the body.

Fig. 11 shows a plan view of a puncture needle according to the invention, as shown in fig. 11, the puncture needle 1-1 being centered in position by means of, for example, 3 positioning struts 1-2 arranged at 120 degrees from one another in the circumferential direction. Therefore, when the positioning supporting feet 1-2 are clamped between the covered stent B and the tissue surface of the branch blood vessel, the positioning supporting feet 1-2 and the conveying sheath 2-2 fixedly connected with the positioning supporting feet are ensured to have reliable coaxiality with the branch blood vessel, and the precision of the vertical puncture windowing is further ensured; further, when the windowing operation is performed, since these positioning struts 1-2 are sandwiched between the stent graft and the blood vessel prior to the puncture needle, the windowing operation is performed on the stent graft by the puncture needle. The locating supporting feet do not move towards the far side along with the puncture needle, the position of the outer wall of the covered stent B is determined through the position of the supporting feet, and therefore the depth of the puncture needle puncturing the covered stent can be determined by means of the supporting feet as a reference, and the puncture needle can be prevented from excessively extending into the covered stent to puncture the blood vessel on the opposite side. It should be noted that although the positioning feet 1-2 are 3 in this example, which are disposed 120 degrees apart from one another, other numbers or angular intervals of the positioning feet 1-2 are possible.

While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified by incorporating any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.

Claims (12)

1. An in situ fenestration apparatus adapted to enable vertical puncture of a stent graft for fenestration at a branch vessel in the body, comprising:

a hand-held assembly located proximal to the in situ fenestration instrument and configured to allow the in situ fenestration instrument to be held and manipulated;

a delivery assembly connected to a distal end of the handpiece assembly, comprising a delivery sheath connected to the handpiece assembly and an internally pushing ram coaxially axially movable within the delivery sheath; and a puncture assembly connected to the delivery assembly, comprising a puncture needle connected to the distal end of the push-in rod and a plurality of positioning struts fixed to the outside of the distal end of the delivery sheath, wherein the plurality of positioning struts are transformable from a collapsed state to an expanded state when the delivery assembly is guided to the ostium of the branch vessel by means of the guide catheter, so as to vertically position the delivery sheath relative to the stent graft and thereby allow the puncture needle to be pushed out through the push-in rod to vertically puncture the stent graft for fenestration.

2. The in situ fenestration instrument of claim 1, wherein the delivery assembly further comprises a tear-away protective loading tube capable of being placed over the outside of the delivery sheath and configured to constrain expansion of the plurality of positioning struts by its inner wall so as to maintain the plurality of positioning struts in a collapsed state and to enable the delivery sheath and the plurality of positioning struts to be removed therefrom when secured at the exit of the vascular sheath, thereby releasing the constraint on the positioning struts to transition to an expanded state.

3. The in situ windowing instrument according to claim 1, wherein the positioning struts are made of a shape memory metal, preferably nitinol, preferably comprising 3 to 6 tentacles arranged substantially uniformly along the circumference of the delivery sheath.

4. The in situ windowing apparatus according to claim 1, wherein the surface of the positioning leg is provided with a developer coating, preferably applied electrochemically, by spraying or by adhesive riveting.

5. The in situ windowing instrument as in claim 1, wherein the puncture needle and the push-in pusher are each configured as hollow tubes with a guidewire lumen for a guidewire to pass through, wherein the guidewire lumen is configured to accommodate a guidewire up to 0.035 inches.

6. The in situ windowing instrument of claim 1, wherein the delivery assembly is sized to be placed within a sheath having a tube diameter in the range of 4 french (Fr) and 6 french (Fr).

7. The in situ windowing instrument of claim 1, wherein the hand held assembly comprises a puncture button disposed on the body of the handle, and wherein the push-in plunger is coupled to the puncture button for causing the push-in plunger and the puncture needle to extend axially distally relative to the delivery sheath upon distal movement of the puncture button relative to the body of the handle.

8. The in situ windowing instrument of claim 7, wherein the hand held assembly further comprises a Y-catheter hub disposed distal to the handle body and coupled to the proximal end of the delivery sheath, wherein the Y-catheter hub is provided with a catheter lumen for holding the delivery sheath and for passing the pusher rod therethrough and a delivery port for delivering the contrast media.

9. The in situ windowing instrument of claim 8, wherein the hand held assembly further comprises a strain relief tube located distally of the handle body, wherein a proximal side of the strain relief tube is connected to the Y-catheter hub.

10. The in situ windowing instrument of claim 8, wherein the handle body has a recess for holding a Y-catheter hub and a puncture button and a slide for sliding the puncture button back and forth along the handle body.

11. The in situ windowing instrument of claim 1, wherein the puncture needle extends from the distal end of the delivery sheath by a length in the range of 1 to 25 mm.

12. The in situ windowing instrument of claim 1, wherein the tip of the puncture needle carries visualization indicia.

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