Controlled and precise stent placement at the coronary ostium during percutaneous coronary intervention

Abstract

The stent delivery system (100) comprises a balloon expandable stent (10) having a guidewire (31) for guiding the stent (10) into a target vessel (V1) to treat a stenosis (4) in the target vessel (V1) with the stent (10) to be delivered to a predetermined stent position (Xs). An anchor wire (32) is provided through an anchor port (52) for fixing the stent (10) by entering a lumen or a second vessel (V2) branching from the target vessel (V1) at a bifurcation position (Xb). The anchor port (42) is freely adjustable along a length (ΔX) of the guidewire (31) to adjust the anchor position (Xa) relative to the stent position (Xs) and vice versa. An anchor positioning means (41) is connected to the anchor port (42) and configured to control the freely adjustable anchor position (Xa) relative to the stent position (Xs), for example by pushing or pulling a hypotube.

Description

[Technical field]

[0001] The present invention relates to a system for delivering a stent to a stenosis in a target vessel adjacent to a bifurcation location where the target vessel branches off from a lumen or a second vessel (carina or bifurcation). The present invention also relates to a kit of parts for constructing such a system, and an anchor port assembly for use in the stent delivery system or kit of parts. [Background technology]

[0002] Coronary artery stenosis is a universal disease. Since the introduction of percutaneous coronary intervention (PCI) in 1977 by Andreas Grünzig, both the number of PCIs as well as the development of techniques and devices have seen exponential growth. Currently, almost all technical aspects of coronary artery disease have been addressed, including the much-awaited successful treatment of chronic total occlusions. Although PCI of coronary artery lesions located at or near the coronary ostium is often followed up and is part of mainstream clinical practice, this procedure can be technically challenging.

[0003] Accurate positioning of the coronary stent at the coronary ostium (proximal end of the coronary artery) is of great importance if pursued. Although more challenging than conventional lesions, the operator is limited to the same palette of PCI techniques, including 2D angiography and the resulting restriction of patient-induced motion. This can result in excessive radiation, use of contrast agents, and uncontrolled / undesirable positioning of the coronary stent.

[0004] The problem of stent placement can be addressed by the so-called "tail wire" or "Szabo" technique. The tail wire technique uses the most proximal stent strut as an anchor for passing a second or "anchor" wire. The anchor wire is placed in a space where the stent should not protrude, usually the aorta, or in the case of a bifurcation, in a side branch. The anchor stops the stent from advancing into the coronary artery and positions its proximal portion precisely at the bifurcation. This technique provides more control during stent positioning, which is invaluable in stenting at the coronary ostium, but also requires stent manipulation, which leads to subsequent problems.

[0005] In a previous patent publication WO2019 / 156560A1, the inventors have mitigated the problems of the conventional "tail wire" technique by decoupling the anchoring potential from the stent. In particular, this patent publication describes a system for delivering a stent to a predetermined stent location in a target vessel. The stent is wrapped around an inflatable balloon having a guide channel. A guide wire for entering the target vessel passes through the guide channel to guide the stent into the target vessel. A portion of the inflatable balloon is enveloped by an elastic sleeve. The sleeve also provides an anchor port separate from the stent struts, for example for guiding an anchor wire into a branch vessel. In addition, the sleeve is configured to at least partially prevent or delay the expansion of the inflatable balloon in the wrapped portion compared to another portion of the inflatable balloon facing the stent. The anchor port can be connected to an anchor port line configured to remotely control the exit direction of the anchor port.

[0006] Although the anchor ports in the known system of WO2019 / 156560A1 have the advantage of preventing damage to the stent by not being directly connected to the stent struts, the inventors have now recognized disadvantages of the known system. First, it is recognized that the anchor ports are still fixed to the inflatable balloon inside the stent via an elastic sleeve. In essence, the elastic sleeve wrapped around the balloon forming the anchor ports, and the stent wrapped around the same balloon, can only be delivered to the patient as a single unit. In practice, surgeons typically first insert the main guidewire and anchor wire into their respective branches before the stent with anchor ports is threaded along both of these wires. Unfortunately, these wires can inadvertently rotate relative to one another during delivery. This can be problematic when the stent with anchors is advanced as a single unit along the rotating wire (passing through the stent balloon and anchor port, respectively) since the fixed position of the anchor ports does not allow the wires to be easily angled out. Thus, entanglements can become even more concentrated by being pushed along the wire until they can become jammed. Additionally, it is recognized that while the anchor ports of known systems allow for adjustment of the angle of the anchor wires exiting the anchor ports, the location of the anchor ports relative to the stent location is fixed, which may limit the ability to control the location of the stent relative to the location of the anchor wires. Summary of the Invention [Problem to be solved by the invention]

[0007] There remains a need for further improvements that can alleviate one or more problems of known stent delivery systems while retaining at least some of the advantages. In particular, the present inventors have recognized the problem of guidewire entanglement in known systems and the need for greater freedom to determine the exact location of stent placement relative to a branched vascular structure while maintaining the necessary precision and control over stent deployment. [Means for solving the problem]

[0008] An aspect of the invention relates to a system or kit of parts for delivering a stent. Specifically, the system is configured to deliver a stent to a predefined stent location in a target vessel adjacent a bifurcation location where the target vessel branches off from a lumen or a second vessel. A stent delivery system typically includes a balloon expandable stent that is advanced over a guidewire to enter the target vessel. A secondary guidewire can be introduced that enters a side branch or any other adjacent vascular structure such as the aorta. The secondary guidewire is used in conjunction with the invention to provide an anchor or tail wire so that the location of the stent can be moved relative to the bifurcation location. In particular, the anchor wire can pass through an anchor port to fix the location accordingly.

[0009] In contrast to previous solutions, as described herein, the anchor port location is separated from the stent delivery catheter. Moreover, the anchor port may not only serve as an anchor point for the anchor guidewire, but also as a lumen for advancing the stent delivery catheter and associated guidewire therethrough. As a result of the balloon inflator connection hub, guidewire, anchor port assembly described herein, and stent delivery catheter being part of a standard stent delivery catheter, they typically need to be introduced into the patient in their respective order. Advantageously, the anchor port is freely adjustable along the length of the guidewire relative to the stent location. Similarly, both the stent delivery catheter and the fixed guidewire are free to move axially relative to each other, preventing guidewire entanglement or entanglement with the struts of the compressed stent. Furthermore, the stent location can also be adjusted relative to the anchor location (determined by the anchor wire relative to the bifurcation location). As will be appreciated, this configuration can provide improved control over the exact stent location while maintaining the precision provided by the fixation relative to the bifurcation location. For example, this may be compared with other solutions in which the anchor port is fixed relative to the stent as disclosed in the inventor's aforementioned patent publications, either by being formed by the stent struts (as in the conventional Szabo technology) or by being connected to a sleeve that is immovable by being wrapped around the balloon and therefore not freely adjustable. Furthermore, as described herein, an anchor positioning means, preferably comprising a hypotube or a rigid control wire, is directly or indirectly connected to the anchor port to control its freely adjustable position, for example by pushing or pulling the hypotube. This differs from the inventor's aforementioned prior patent publications, in which the anchor port is optionally connected to an anchor port line, but only for adjusting its orientation, and is not suitable for changing its position relative to the balloon, at least not by pushing the wire.Furthermore, it was found that the anchor port of the prior patent publication was inherently fixed to the stent via the elastic sleeve and balloon, which could lead to entanglement of the guidewire and anchor wire. This problem is mitigated because the wires are free to rotate relative to each other inside a separate, freely adjustable anchor port. Together, the features of the present anchor port assembly mitigate entanglement of the wires when advancing the stent, allowing greater freedom to adjust the exact location of the main wire and anchor wire relative to the balloon / stent split into their respective vessels. Further synergistic aspects include providing the anchor port with a radiopaque material that allows for precise placement of the device. Further aspects also include the ability to form the anchor port as an expandable tubular member that can slide over the proximal portion of the balloon and prevent or delay balloon inflation.

[0010] Another or further aspect relates to a fixation assembly for complementing a balloon expandable stent delivery system. The assembly can act as a visual and mechanical aid for accurately positioning and / or fixing a coronary stent, for example at the coronary ostium defined by the so-called "carina". Also, other types of stents can benefit from the assembly. For example, although the accuracy of accurate positioning in coronary vessels is the most difficult, similar techniques can be applied to other (larger) vessels, such as bifurcations in renal vessels (arteries and veins), leg vessels, cerebral vessels, etc. As described herein, the device consists of an anchor positioning means connected to a ring or tubular extension, which may preferably contain a radiopaque material, defining the exact location of the ostium and allowing the operator to accurately target the desired stent location, in particular by using two separate guidewires in combination, one positioned in the target vessel and the other in an adjacent structure (e.g., a branch vessel). For example, after positioning of both guidewires, the ostium can be marked by carefully pushing the tubular extension until resistance is met and mechanically and then visually identifying the carina.

[0011] By providing the anchor port with an opening having a minimum inner diameter larger than the outer diameter of the compressed stent prior to balloon expansion, the compressed stent can be threaded through the opening of the anchor port to the stent location after the anchor port has been guided to the anchor location along the guidewire and anchor wire. For example, the anchor port assembly may be used in combination with relatively small stents, such as coronary stents. For these and other typical sizes of stents, the assembly may include an anchor port formed by a ring or tubular shape, preferably having a minimum inner diameter of 1-2 millimeters. Other diameters may also be used depending on the size of the compressed stent that can be fitted through the anchor port.

[0012] By forming the anchor positioning means of the main cord terminating in a set of branch cords and interconnecting the main cords with the anchor ports at various locations around the opening, the inventors find that it may be easier for the assembly to be retracted, for example into a guide catheter, mitigating the potential problem that the anchor ports may become clogged, which is more likely to occur if the tube or ring is connected only at one location around the circumference. By forming the branch cords of an elastic material or structure configured to recover its shape after deformation, it may be relatively easy to pass compressed stents between the branch cords, which may then recover so that they can be retracted more easily. Similarly, by forming the anchor ports of the same or different elastic material, or any structure configured to recover its shape after deformation, it may be relatively easy to pass compressed stents through the anchor ports, while the shape is then recovered to perform the function of balloon fixation and / or delayed inflation.

[0013] By forming the main cord made of hypotubes or rigid control wires, the anchor position can be more precisely controlled and / or maintained. The individual branch cords may be relatively flexible compared to the main cord, but in combination may provide sufficient rigidity to control and / or maintain the anchor position. The main cord, for example made of hypotubes or (rigid) control wires, typically has an outer diameter smaller than the outer diameter of the anchor port, for example less than 2 mm, preferably less than 1 mm, for example 0.2-0.5 mm. To reach sufficiently inside the body, the main cord typically has a length of at least half a meter, preferably at least 1 meter.

[0014] These and other features, aspects, and advantages of the apparatus, systems, and methods of the present invention will become better understood from the following description, appended claims, and accompanying drawings. [Brief description of the drawings]

[0015] [Figure 1A] 1 illustrates the delivery and deployment of a stent to treat a stenosis in a target vessel near a bifurcation with a second vessel. [Figure 1B] 1 illustrates the delivery and deployment of a stent to treat a stenosis in a target vessel near a bifurcation with a second vessel. [Figure 2A] 1 illustrates the use of a stent delivery system, including a preferred sequence of steps for delivery. [Figure 2B] 1 illustrates the use of a stent delivery system, including a preferred sequence of steps for delivery. [Figure 2C] 1 illustrates the use of a stent delivery system, including a preferred sequence of steps for delivery. [Figure 2D] 1 illustrates the use of a stent delivery system, including a preferred sequence of steps for delivery. [Figure 3A] 1 illustrates details of a fixation assembly used in a stent delivery system. [Figure 3B] 1 illustrates different fastening assemblies. [Figure 3C] 1 illustrates different fastening assemblies. [Figure 3D] 1 illustrates different fastening assemblies. [Figure 4A] 13 shows a further aspect of the fastening assembly. [Figure 4B] 13 shows a further aspect of the fastening assembly. [Figure 4C] 13 shows a further aspect of the fastening assembly. [Figure 4D] 13 shows a further aspect of the fastening assembly. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The terms used to describe certain embodiments are not intended to limit the invention. As used herein, the singular forms "a," "an," and "the" are intended to include the plural unless the context clearly indicates otherwise. The term "and / or" includes any and all combinations of one or more of the associated listed items. It will be understood that the terms "comprises" and / or "comprising" specify the presence of a stated feature but do not exclude the presence or addition of one or more other features. When a particular step of a method is referred to after another step, it will be further understood that the other step can follow directly or one or more intermediate steps can be performed before performing the particular step, unless otherwise specified. Similarly, when a connection point between structures or components is described, it will be understood that the connection point can be established directly or through an intermediate structure or component, unless otherwise specified.

[0017] The present invention will now be described more fully with reference to the accompanying drawings, in which embodiments of the invention are shown. In the drawings, absolute and relative sizes of systems, components, layers, and regions may be exaggerated for clarity. The embodiments may be described with reference to schematic illustrations and / or cross-sectional views of idealized embodiments and intermediate structures of the invention in some cases. In this specification and the drawings, like numbers refer to like elements throughout. Relative terms and derivatives thereof should be construed to refer to the orientation as described then or as shown in the drawings under discussion. These relative terms are for convenience of description and do not require that the system be constructed or operated in a particular orientation, unless specifically stated otherwise.

[0018] Figures 1A and 1B show the delivery and deployment of a balloon expandable stent 10 to treat a stenosis 4 in a target vessel V1 near a bifurcation with a second vessel V2. Figures 2A-2D show the use of stent delivery system 100 and include a preferred series of steps for delivery. Other uses and / or sequences of steps may also be envisioned.

[0019] In some embodiments, the system includes an inflatable balloon 20. In one embodiment, the stent 10 includes a stretchable frame 11 wrapped around the inflatable balloon 20. In another or further embodiment, the system includes a guidewire 31 for entering the target vessel V1. For example, the guidewire 31 may pass through a guide channel 21 inside the stent or balloon to guide the inflatable balloon 20 into the target vessel V1 together with the stent 10 (while compressed) or together with the guidewire 31.

[0020] In some embodiments, the system comprises an anchor wire 32 for determining an anchor position Xa relative to a bifurcation position Xb where the target vessel V1 branches from the lumen or a second vessel V2. In one embodiment, the system comprises an anchor port 42 through which the anchor wire 32 passes in use to determine an anchor position Xa relative to a stent position Xs. Typically, the guide wire 31 and the anchor wire 32 may first be positioned in the respective vessels V1, V2, as shown, for example, in Figures 2A and 2B, after which the anchor port 42 is guided from the outside into the patient via the two wires and then advanced to the tracheal bifurcation, as shown, for example, in Figure 2C. It will thus be understood that the anchor port 42 is preferably not fixed, i.e. not anchored, to either the inflatable balloon 20 or the balloon-expandable stent 10. The anchor position Xa of the anchor port 42 is therefore freely adjustable along the length ΔX of the guide wire 31 relative to the stent position Xs of the stent 10. In a preferred embodiment, an anchor positioning means 41 is provided having a distal end connected to the anchor port 42. The proximal end of the anchor positioning means 41 is configured to control the freely adjustable anchor position Xa relative to the stent position Xs by pushing or pulling the proximal end. Most preferably, the anchor positioning means 41 comprises a hypotube directly or indirectly connected to the anchor port 42 for controlling the freely adjustable anchor position Xa relative to the stent position Xs, for example by pushing or pulling the hypotube 41.

[0021] For example, US Patent Application Publication No. 2017 / 0274179(A1) describes hypotube structures. As described in this prior art, hypotubes are typically long metal tubes with micromachined features along their length. Hypotubes can be used as components of minimally invasive catheters in conjunction with balloons and stents to open blocked arteries. Typically, the balloon portion of the catheter can be attached to the head of the hypotube. The hypotube can have reinforcements that can give the liner more support and integrity as the catheter navigates the vasculature to the treatment location. In some instances, a polymer jacket is dispensed on the outer diameter of the hypo outer to provide a seal and to minimize any surface roughness imparted by the laser cutting of the hypo outer while still providing flexibility. Other types of hypotubes may also be used.

[0022] By connecting the anchor port 42 to a hypotube as described herein, the freely adjustable anchor position Xa relative to the stent position Xs can be more precisely controlled, for example, by pushing or pulling the hypotube. Furthermore, the controllable position can be more precisely maintained, particularly when the balloon is inflated. Alternatively, or in addition to a hypotube, other or even relatively rigid and / or incompressible structures, such as rigid, e.g., metal wires, that are not necessarily tubes, e.g., hollow, can be used.

[0023] In some embodiments, the anchor port 42 is formed by a ring-shaped and / or tubular member connected to the hypotube 41. In one embodiment, the guidewire 31 passes through the anchor port 42. For example, a proximal portion of the guidewire 31 may be inside a second hypotube connected to a balloon expandable stent. In another or further embodiment, the guidewire 31 and the anchor wire 32 each pass through the same opening of the anchor port 42, for example through a ring or tube forming the anchor port. For example, this provides an easy construction with a single opening for guiding both wires (and the stent). Alternatively, there may be separate openings for each wire.

[0024] In some embodiments, the anchor port 42 is configured to fit at least a portion of the inflatable balloon 20 inside. For example, a portion of the inflatable balloon 20 (before deployment) can fit inside the anchor port 42, e.g., up to or even beyond the expandable frame 11. By fitting a portion of the balloon 20 inside the anchor port 42 while the balloon is inflated, the anchor port 42 can at least partially prevent and / or delay the inflation of a portion of the balloon. This is a common phenomenon during percutaneous interventions and can be advantageous to further control the inflation process, e.g., prevent the stent frame from shifting during inflation, according to the characteristics of the stenosis or stenosis that are disadvantageous in the treatment of ostial lesions.

[0025] In some embodiments, the compressed stent 10, i.e., the undeployed stent frame 11 around the deflated balloon, may fit completely inside and / or be guided through the anchor port 42, for example, as shown in Figures 2C and 2D. This may be advantageous, for example, when the stent 10 is routed along the guidewire 31 after the location of the anchor port 42 has been established. For example, Figure 1B shows a deployed stent, with the proximal side 20p of the inflated balloon partially inflated inside the tubular extension that forms the anchor port 42. Preventing or delaying expansion may, for example, prevent the stent frame from moving away from its intended position during expansion.

[0026] 3A illustrates details of an anchoring assembly 40 for use in a stent delivery system 100, such as those described herein. For example, the anchoring assembly 40 can be a stand-alone device used to supplement an existing stent delivery system.

[0027] In some embodiments, the anchor port 42 (e.g., a tubular member as shown or other tube or ring shape) has a (minimum) inner diameter Dmin Dp that is, for example, at least 1.1 times, 1.5 times, 2 times, or more, larger than the cumulative outer diameter of the guidewire 31 and the anchor wire 32. For example, the minimum inner diameter Dp is more than twice the outer diameter of each of the guidewire 31 and the anchor wire 32. This allows each of the guidewire 31 and the anchor wire 32 to slide freely through the anchor port 42 and / or allows the anchor port 42 to be freely adjustable along the wire. Typically, the anchor port 42 is at least a larger diameter than the hypotube 41 that is used to control its position. In one embodiment, the anchor port 42 has an outer diameter that is, for example, at least 2 times, 4 times, 6 times, 8 times, 10 times, or more, larger than the outer diameter of the hypotube 41.

[0028] In some embodiments, anchor port 42 is formed by a tubular member shaped to slide over a proximal region of inflatable balloon 20 to at least partially prevent and / or delay inflation in the proximal region. In one embodiment, anchor port 42 has an inner diameter Dd at least distally facing the proximal side of inflatable balloon 20 that is greater than an outer diameter Db of inflatable balloon 20 (before inflation). This allows at least a portion of inflatable balloon 20 to fit inside anchor port 42, as described above.

[0029] In some embodiments, the anchor port 42 has a minimum inner diameter Dmin that is larger than the outer diameter Ds of the (compressed) stent 10 before the expansion of the balloon 20. This allows the compressed stent 10 to fit inside and pass through the anchor port 42. In other or further embodiments, the anchor port 42 has a minimum inner diameter Dmin that is (slightly) larger than the cumulative outer diameter of the anchor wire 32 and the (compressed) stent 10 before the expansion of the balloon 20, for example, 1.01 to 1.5 times larger, preferably 1.05 (5% larger) to 1.3 (30% larger) times larger. This allows the compressed stent 10 to fit inside and pass through the anchor port 42 even when the anchor wire 32 has already passed through the anchor port 42, as shown, for example, in FIGS. 2C and 2D.

[0030] In a typical balloon expandable stent for application in coronary arteries, before deployment, the outer diameter Ds of the (compressed) stent is typically between one-tenth of a millimeter and four millimeters, more typically between 0.3 and 2 mm. The minimum inner diameter Dmin of the anchor port 42 is preferably slightly larger, e.g., at least one-tenth of a millimeter (0.1 mm) larger than the outer diameter Ds of the compressed stent. For example, the thickness of the guidewire 31 and / or the anchor wire 32 is typically less than one millimeter, more typically less than half a millimeter, e.g., 0.3 mm. Thus, in one embodiment, the minimum inner diameter Dmin of the anchor port 42 is typically less than half a centimeter, preferably 0.4 to 2.5 mm, more preferably 1 to 2 millimeters, most preferably 1.2 to 1.5 mm, or more, depending on the stent. When deployed, the diameter may increase, for example, by 1.5 to 2.5 times, or more, e.g., by 2 mm to 5 mm, or more. Typical lengths of stents (frames) may vary, for example, from 8 to 40 mm, more usually from 10 to 30 mm, or from 12 to 20 mm.

[0031] In some embodiments, the system 100 comprises a (coronary) guide catheter 1 having an inner diameter Dc configured to fit the maximum outer diameter of the inner anchor port 42 to guide the anchor port 42 through the guide catheter 1. For example, the maximum outer diameter of the anchor port 42 is slightly larger than its maximum inner diameter Dd (depending on the thickness of the vessel wall or ring). In other or further embodiments, the hypotube 41 is configured to push the anchor port 42 through the guide catheter 1, along the guidewire 31 and / or anchor wire 32, and beyond the distal end of the guide catheter 1.

[0032] In some embodiments, the anchor port 42 is shaped as a tubular member having a length Lt greater than its (minimum and / or maximum) inner diameter Dp, Dd. In a typical balloon expandable stent, the expandable balloon, or at least the portion that expands in diameter, extends beyond the edge of the stent frame, for example, at least one hundredth of a millimeter, more typically at least one tenth of a millimeter, for example, 0.1 to 5 mm, or more. In one embodiment, the length Lt of the anchor port 42 is the same as or similar to the length of the (expandable) portion of the balloon that extends beyond the stent frame, for example, 1.2 times, or 1.5 times, up to 2 times, or more. Thus, in one embodiment, the length Lt of the anchor port 42 is 1 to 20 mm, more typically 4 to 15 mm, or 6 to 10 mm, depending on the length of the stent or any other suitable length. Preferably, there is no continuous closed lumen between the guide catheter and the anchor port to prevent high pressure accumulation of fluid, such as contrast media, at the distal end of the anchor port. Alternatively, for example, as shown in FIG. 3D, the tubular member may be embodied as a relatively short tube, such as a ring.

[0033] In some embodiments, for example, as shown in Figures 3A and 3B, the anchor port 42 is formed by an elongated tubular member having a proximal end, where the anchor port 42 is connected to the anchor positioning means 41, and a distal end facing the proximal end, the elongated tubular member having an (internal) proximal diameter Dp (e.g., determining a minimum diameter Dmin) at the proximal end, and the diameter increasing toward an (internal) distal diameter Dd at the distal end. For example, the increasing diameter may allow a relatively large opening angle between the guide wire 31 and the anchor wire 32 to exit the distal end of the tubular member, and still substantially prevent or delay inflation of a portion of the balloon 20. For example, the tubular member has a hollow shape of a truncated cone. Other diverging shapes may also be used. In other or further embodiments, for example, as shown in Figure 3C, the anchor port 42 is formed by an elongated tubular member having an (internal) diameter Dd that increases toward both the distal and proximal ends. For example, the tubular member may have a relatively low waist diameter Dw at the distal and / or proximal ends relative to the diameters Dd, Dp, e.g., at least 10%, 20%, up to 50% or more lower. In other or further embodiments (not shown), the tubular member may be a straight tube, e.g., having a relatively large diameter to allow for a large opening angle.

[0034] In some embodiments, the anchor port 42 comprises a stiff material, for example compared to the material of the balloon 20. For example, the balloon is made of rubber or nylon. For example, the material of the anchor port 42 has a Young's modulus of greater than 0.1 GPa, typically greater than 1 GPa. In one embodiment, the anchor port 42 comprises a tubular member having a (relatively stiff) midsection and at least one end section having greater flexibility than the midsection. For example, by having more flexibility at one or both ends, this can facilitate a larger angle between the guidewire 31 and the anchor wire 32 guided therethrough, while still preventing or slowing the inflation of the balloon. In other or further embodiments, the anchor port 42 comprises and / or is shaped as a groove and / or has any other interruption in its circular form. For example, this can prevent potentially harmful pressure buildup of fluids, such as contrast media, at the distal end of the anchor port 42.

[0035] In some embodiments, the anchor port 42 includes a radiopaque material 42r. Those skilled in the art will appreciate that a radiopaque material has a relatively high absorbance to X-rays, at least to the extent that it is typically visible and distinguishable (e.g., from the biological tissue background) in a radiographic image of the body. In contrast, a radiolucent or radiotransparent material is essentially transparent to X-rays, and as a result is typically invisible or barely visible in a radiographic image, e.g., has similar X-ray characteristics to the tissue background. Thus, by providing the anchor port 42 with a radiopaque material 42r, an operator of the system can easily identify the location of the anchor port 42 in the body using radio / X-ray imaging. Typically, at least a portion of the stent, e.g., the outer edge, is also provided with a radiopaque material. This allows it to be determined in the radiographic image where the stent is located. For example, the radiopaque material 42r of the anchor port 42 can be the same or similar to the radiopaque material provided on the stent. By providing both anchor port 42 and stent 10 with respective radiopaque materials, it becomes possible to determine in an X-ray image where anchor port 42 is located relative to the stent, which can help to further control its deployment.

[0036] In some embodiments, the anchor port 42 has a tubular shape and comprises a radiopaque material 42r arranged (at least or exclusively) at the distal edge of the tubular shape (opposite the anchor positioning means 41), for example forming a radiopaque ring at the distal edge. In this way, the exact location of the distal end can be more precisely distinguished, which is most relevant since it forms the exit ports of the different wires and determines the location where the inflation of the balloon may be prevented. For example, the remaining part of the tubular shape, for example the proximal region, is formed by a radiolucent or radiotransparent material, for example a material that is at least more transparent to X-rays than the radiopaque material 42r.

[0037] As described herein, the anchor positioning means 41 is preferably configured to allow various forms of control over the positioning of the anchor port 42, for example to allow the anchor port 42 to be pushed towards the stent / balloon. Preferably, the anchor positioning means comprises a hypotube 41 that is attached directly or indirectly to the proximal edge of the anchor port 42. The hypotube is typically manufactured to have a diameter of 0.2-5 mm. In some embodiments, the system comprises multiple hypotubes. In one embodiment, the anchor port 42 is connected to a first hypotube 41 and the balloon-expandable stent 42 is connected to a separate second hypotube. In principle, the second hypotube can be the same or similar to the first hypotube. Typically, the second hypotube connected to the stent may be different, e.g., it may have a larger diameter to accommodate a balloon inflation channel inside. Also, the guidewire 31 may be housed inside the second hypotube that leads to the balloon-expandable stent.

[0038] For the purposes of the present invention, the anchor positioning means 41, e.g., a hypotube (or other rigid control wire), directly or indirectly connected to the anchor port 42, preferably has a relatively small (inner and / or outer diameter), e.g., less than 2 mm, less than 1 mm, less than 0.5 mm, or even less than 0.3 mm. Typically, the hypotube 41 is hollow, but if it is used only to manipulate the anchor port 42, the tube may be filled. The hypotube has the particular advantage of being controlled with a minimal thickness, but in principle it can also be replaced by a tube and / or wire-like structure, e.g., Nitinol, that allows similar manipulations, such as pushing and pulling the anchor port 42. In one embodiment, the hollow hypotube 41 is further used as a guide, e.g., to guide the anchor wire 32 inward. For example, the proximal end of the hollow hypotube 41 can terminate inside or before (proximal to) the anchor port 42 so that the anchor wire 32 can exit through the anchor port 42.

[0039] In some embodiments, the hypotube 41 is formed by a long tube, for example formed from a metal or other material, typically having micro-engineered features along its length. For example, the micro-engineered features may include one or more of a continuous or interrupted helical cut pattern, a radial cut pattern, cut holes, and the like. To facilitate deployment and / or prevent damage, the hypotube 41 may be coated, for example with Teflon. Typically, the hypotube 41 has a length similar to the wires 31, 32 and / or channels leading to the inflatable balloon. For example, the length Lh of the hypotube 41 is at least ½ meter, more typically at least 1 meter, for example 1.2 to 2.5 meters, or more. Each of the hypotube 41 and the anchor port 42 is typically a medical grade material.

[0040] 4A-4D show further aspects of the anchoring assembly 40. In some embodiments, the anchor positioning means 41 comprises a main cord 41m terminating in a set of branch cords that interconnect the main cord 41m with the anchor port 42. In one embodiment, for example, as shown in Figures 4A and 4C, the anchor positioning means 41 comprises two branch cords 41a, 41b. In another or further embodiment, for example, as shown in Figures 4B and 4D, the anchor positioning means 41 comprises three branch cords 41a, 41b.

[0041] In some embodiments, the anchor port 42 comprises a proximal rim 42p forming part of an opening through which the anchor wire 32 can be passed. In one embodiment, the branch cords 41a, 41b, 41c are connected at different positions around the circumference of the opening, for example to the proximal rim 42p. This may allow one or more, preferably each, of the guide wire 31, the anchor wire 32 and the compressed stent to pass between the branch cords 41a, 41b, 41c and through the opening of the anchor port 42. In principle, more than three branch cords, for example four, can be used, but this may begin to impede the ability to pass other parts of the system to pass between them. Therefore, preferably the number of branch cords is limited to two or three. Most preferably the two, three or more branch cords 41a, 41b, 41c are distributed equidistantly around the circumference of the proximal rim 42p. This configuration may, on the one hand, allow for easier passage through other parts of the system, as well as forming a structure that can be more easily retracted, for example, into a guide catheter or otherwise.

[0042] In some embodiments, the anchor positioning means 41 comprises a hypotube or a (rigid) control wire configured to control the freely adjustable anchor position, e.g., relative to the stent position, by pushing and pulling the hypotube. In other or further embodiments, the main cord 41m is formed by a hypotube or a rigid control wire. In one embodiment, the branch cords 41a, 41b, 41c are formed of an elastic material or are structures configured to recover their shape after deformation. In another or further embodiment, the anchor port 42 is formed of an elastic material or are structures configured to recover their shape after deformation. Preferably, one or more of the branch cords and / or anchor ports comprise or are essentially formed of Nitinol. Nitinol (nickel-titanium) is a shape memory alloy that exhibits a variety of properties that are particularly suitable for the present application, including its shape memory effect, superelasticity, high corrosion resistance, biocompatibility, high fatigue resistance, low coefficient of friction, high strength-to-weight ratio, etc. Of course, other suitable elastic materials may be used. Alternatively, or in addition to using a resilient material, anchor port 42 may include a spring structure forming part of a ring (not shown).

[0043] In some embodiments, the anchor port 42 is formed by a ring-shaped member, as shown, for example, in Figures 4A and 4B. In other embodiments, the anchor port 42 is formed by a tubular member, as shown, for example, in Figures 4C and 4D. Of course, the anchor port 42 (connected to the main cord 41m via the branch cord set 41a, 41b, 41c) can take any of the shapes as described above with reference to any of Figures 3A-3D, providing similar advantages. In a preferred embodiment, as shown, for example, in Figures 4C and 4D, the anchor port 42 comprises a radiopaque material 42r. For example, the tubular shape comprises a ring of radiopaque material 42r at the distal end of the tube. Similarly, in an embodiment in which the anchor port 42 is formed by a ring shape, as shown, for example, in any of Figures 4A, 4B, or by a relatively short tube, as shown, for example, in an embodiment in which the anchor port 42 is formed by a relatively short tube, the entire ring or the short tube may comprise or be substantially formed by the radiopaque material 42r.

[0044] In interpreting the appended claims, it should be understood that the word "comprises" does not exclude the presence of other elements or acts than those recited in a given claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. Any reference signs in the claims do not limit their scope. Several "means" may be represented by the same or different item(s) or implemented structure or function. Any of the disclosed devices or parts thereof may be combined together or further parts, unless otherwise stated. When one claim refers to another claim, this may indicate synergistic advantages achieved by the combination of their respective features. However, the mere fact that certain measures are recited in mutually different claims does not indicate that a combination of these measures cannot also be used to advantage.

Claims

1. a balloon-expandable stent (10) comprising a stent frame (11) wrapped around an expandable balloon (20) and a guidewire (31) for guiding the stent (10) into a target vessel (V1) for treating a stenosis (4) in the target vessel (V1) with the stent (10) delivered to a predetermined stent position (Xs); an anchor wire (32) for anchoring the stent (10) by entering a lumen or a second vessel (V2) branching from the target vessel (V1) at a branching location (Xb); an anchor port (42) configured to pass through and be guided along by both the guide wire (31) and the anchor wire (32), determining an anchor position (Xa) relative to the stent position (Xs), the anchor position (Xa) of the anchor port (42) being freely adjustable along a length (ΔX) of the guide wire (31) for adjusting the anchor position (Xa) relative to the stent position (Xs), or vice versa; an anchor positioning means (41) having a distal end connected to said anchor port (42) and a proximal end configured to control, by pushing and pulling, said anchor position (Xa) freely adjustable relative to said stent position (Xs); A stent delivery system (100) comprising:

2. 2. The system of claim 1, wherein the anchor port (42) has an opening having a minimum inner diameter (Dmin) greater than an outer diameter (Ds) of the compressed stent (10) before expansion of the balloon (20), allowing the compressed stent to be passed through the opening of the anchor port (42) to the stent location (Xs) after being guided to the anchor location (Xa) along the guide wire (31) and the anchor wire (32).

3. said anchor positioning means (41) comprising a main cord (41m) terminating in a set of branch cords (41a, 41b, 41c) interconnecting said main cord (41m) with said anchor ports (42); the anchor port (42) comprises a proximal rim (42p) forming part of an opening through which the guidewire (31), the anchor wire (32) and the compressed stent can pass; the branch cords (41 a, 41 b, 41 c) are connected at different locations around the proximal limb (42 p) to allow each of the guide wire (31), the anchor wire (32) and the compressed stent to pass between the branch cords (41 a, 41 b, 41 c) and through the openings of the anchor ports (42); The system of claim 2.

4. The system according to any one of claims 1 to 3, wherein the anchor positioning means (41) comprises a hypotube or a stiffness control wire configured to control, by pushing or pulling, the anchor position (Xa) which is freely adjustable relative to the stent position (Xs).

5. 5. The system according to claim 3 and claim 4, wherein the main chord (41m) is formed by a hypotube or a stiffness control wire.

6. 4. A system according to claim 3 or any claim dependent thereon, wherein the branch cord (41a, 41b, 41c) is made from an elastic material or is a structure adapted to recover its shape after deformation.

7. The system of any one of claims 1 to 6, wherein the anchor port (42) is formed from a resilient material or is a structure configured to regain its shape after deformation.

8. The system of any one of claims 1 to 7, wherein the anchor port (42) is formed by a ring or a tubular member.

9. The system of claims 7 and 8, wherein the anchor port (42) comprises a spring structure forming a part of the ring.

10. The system of any one of claims 1 to 9, wherein the anchor port (42) is not fixed to either the expandable balloon (20) or the balloon-expandable stent (10).

11. The system of any one of claims 1 to 10, wherein the anchor port (42) comprises a material that is more rigid than a material forming the balloon (20).

12. The system of any one of claims 1 to 11, wherein the anchor port (42) has a tubular shape and is provided with a radiopaque material (42r) disposed only at the distal edge of the tubular shape to form a radiopaque ring at the distal edge.

13. A kit of parts for assembling a stent delivery system (100) according to any one of the preceding claims.

14. An anchor port assembly (40) for use in a stent delivery system (100) or kit of parts according to any one of claims 1 to 13, comprising: an anchor port (42) formed by a ring or tubular shape having a minimum inner diameter (Dmin) between 1 and 2 millimeters; An anchor positioning means (41) comprising a main cord (41m) having an outer diameter of less than 2 mm, preferably less than 1 mm, and a length of at least 1 meter; Equipped with a distal end of said main cord (41m) terminates in a set of branch cords (41a, 41b, 41c) interconnecting said main cord (41m) with said anchor ports (42); The branch cords (41a, 41b, 41c) are connected to different positions around the anchor port (42). Anchor port assembly (40).

15. the anchor port (42) is formed from a resilient material or is a structure configured to regain its shape after deformation; The set of branch cords consists of two or three branch cords (41a, 41b, 41c) made of elastic material or of a structure adapted to recover its shape after deformation, the main cord (41m) is formed by a hypotube or stiffness control wire having a stiffness and / or thickness greater than one of the branch cords (41a, 41b, 41c); The anchor port assembly (40) of claim 14.

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