Endoscopic ultrasound-guided needle puncture

Abstract

The puncture needle includes a hollow shaft having a lumen sized and shaped to slidably receive a guide wire therein; and having a distal end including an angled surface extending proximally and laterally from a sharp distal-most tip of the shaft to a beveled smooth region of the shaft proximal to and transverse to the sharp tip. The beveled smooth region is positioned to slidably engage a guide wire extending distally from the distal end of the needle so that when the guide wire is proximally retracted into the needle, the beveled smooth region slidably engages the guide wire to minimize wear on the guide wire.

Description

[0001] Priority declaration

[0002] This application claims priority to U.S. Provisional Patent Application Serial No. 62 / 944,725, filed on December 6, 2019; the disclosure of which is incorporated herein by reference. Technical Field

[0003] The present invention relates to an endoscopic needle, and in particular to an endoscopic ultrasound (EUS) guided puncture needle. Background Art

[0004] Hollow needles can be used in EUS-guided surgeries to access target anatomical structures, such as the intestinal lumen, and to introduce a guide wire into the target anatomical structure through the needle lumen to, for example, guide stent implantation surgery. When extending distally from the tip of the needle, the guide wire can bend at different points in multiple directions, such as when a physician attempts to retract the guide wire into the needle, the guide wire may get stuck on the sharp edge or tip of the needle, which may strip the guide wire. The stripped material may remain in the anatomical structure and / or may expose the wire core of the guide wire and cause an electrical safety hazard. Summary of the invention

[0005] The present invention relates to a puncture needle, which includes a hollow shaft, the hollow shaft having a cavity sized and shaped to be configured to slidably receive a guide wire therein; and having a distal end, the distal end including an angled surface extending proximally and laterally from a sharp distal-most tip of the shaft to a beveled smooth area of ​​the shaft, the beveled smooth area being proximal to and transverse to the sharp tip, the beveled smooth area being positioned to slidably engage a guide wire extending distally from the distal end of the needle, so that when the guide wire is retracted proximally into the needle, the beveled smooth area slidably engages the guide wire to minimize wear on the guide wire.

[0006] In one embodiment, the distal end of the shaft includes a sharp cutting surface extending proximally from the sharp tip, and the beveled smooth area is positioned so that when the guide wire extending from the distal end of the needle along the bend is retracted into the needle in a desired direction relative to the needle, the surface of the guide wire forming the radial inner surface along the bend contacts the beveled smooth area of ​​the needle.

[0007] In one embodiment, the distal end of the shaft includes a first sharp cutting surface extending from a distal-most tip to a first transition portion and a second sharp cutting surface extending from the first transition portion to a second transition portion, the first sharp cutting surface extending at a first angle relative to a longitudinal plane of the shaft at the distal-most tip and bending to a second angle relative to the longitudinal plane of the shaft at the first transition portion, and the second cutting surface having a third angle relative to the longitudinal plane of the shaft.

[0008] In one embodiment, the distal end of the shaft includes a third sharp cutting surface extending from a distal-most tip to a third transition portion and a fourth sharp cutting surface extending from the third transition portion to a fourth transition portion, the third sharp cutting surface extending at a fourth angle relative to a longitudinal plane of the shaft at the distal-most tip and bending to a fifth angle relative to the longitudinal plane of the shaft at the third transition portion, and the fourth sharp cutting surface extending at a sixth angle relative to the longitudinal plane of the shaft.

[0009] In one embodiment, the first and second sharp cutting surfaces are substantially symmetrical with respect to the third and fourth sharp cutting surfaces relative to a mid-plane of the needle.

[0010] In one embodiment, the first angle is within a first range of 0 to 10 degrees, the second angle is within a second range of 20 to 50 degrees, and the third angle is within a third range of 10 to 30 degrees.

[0011] In one embodiment, the bevel smoothing region is defined by a U-shaped surface having a midpoint proximal and transverse to the sharp tip, the U-shaped surface having a curvature at the midpoint parallel to a transverse plane of the axis.

[0012] In one embodiment, the bevel smoothing region includes an outer bevel on an outer surface of the shaft and an inner bevel on an inner surface of the shaft.

[0013] In one embodiment, the shaft includes features extending along a distal portion thereof that are configured to mechanically engage corresponding features of a guidewire inserted therein to maintain the guidewire in a desired rotational orientation relative to the needle.

[0014] In one embodiment, the shaft features include a slot extending along a portion of the length of the needle configured to receive a lug extending radially from the guidewire.

[0015] The present invention also relates to a puncture needle assembly, which includes an anchoring guide wire, the anchoring guide wire including a first orientation feature; and a puncture needle, the puncture needle including a hollow shaft, the hollow shaft having a size and shape configured to be able to slidably receive the guide wire therein; and having a distal end, the distal end including a cutting surface, which extends proximally and laterally from the sharp distal-most tip of the shaft to a beveled smooth area of ​​the shaft, the beveled smooth area is proximal to and transverse to the sharp tip, the beveled smooth area is positioned to slidably engage the guide wire extending distally from the distal end of the needle, so that when the guide wire is retracted proximally into the needle, the beveled smooth area can slidably engage the guide wire to minimize wear on the guide wire, the puncture needle also includes a second orientation feature extending along its distal portion, the second orientation feature is configured to mechanically engage the first orientation feature to maintain the guide wire in a desired rotational orientation relative to the puncture needle.

[0016] In one embodiment, the second orientation feature comprises a slot extending along a portion of the length of the needle and the first orientation feature comprises a lug protruding outwardly from the guidewire.

[0017] In one embodiment, the lug has a ramp section to facilitate engagement of the shaft and lug so that when the needle is retracted proximally over the guidewire, the ramp engages the distal end of the slot causing the lug to fold over and pass through the needle until the lug has cleared the distal end of the needle.

[0018] In one embodiment, the second orientation feature comprises a slot extending along a portion of the length of the needle and the first orientation feature comprises a lug protruding outwardly from the guidewire, the lug being configured to shear off the guidewire when the needle is withdrawn proximally over the guidewire.

[0019] In one embodiment, the guidewire has a nitinol core with a polymer coating.

[0020] The present invention also relates to a method comprising extending a guide wire distally from a distal end of a puncture needle, the puncture needle comprising a hollow shaft having a cavity sized and shaped to slidably receive the guide wire therein, the distal end of the needle comprising a cutting surface extending proximally and laterally from a sharp distal-most tip of the shaft to a beveled smooth region of the shaft proximal to and transverse to the sharp tip; retracting the guide wire proximally into the needle so that the beveled smooth region slidably engages the guide wire to minimize wear on the guide wire.

[0021] In one embodiment, the method further includes rotating the guidewire relative to the longitudinal axis of the introducer needle to position the bend of the guidewire so that a portion of the guidewire surface forming a radially inner portion of the bend contacts the beveled smooth region when the guidewire is retracted into the needle.

[0022] In one embodiment, the guidewire is rotated under ultrasound guidance so that the curved distal end bends away from a side of the needle on which the distal tip of the needle is formed.

[0023] In one embodiment, the distal end of the shaft includes a sharp cutting surface extending proximally from the sharp tip, and the beveled smooth area is positioned so that when the guide wire extending from the distal end of the needle along the bend is retracted into the needle in a desired direction relative to the needle, the surface of the guide wire forming the radial inner surface along the bend contacts the beveled smooth area of ​​the needle.

[0024] In one embodiment, the bevel smoothing region is defined by a U-shaped surface having a midpoint proximal and transverse to the sharp tip, the U-shaped surface having a curvature at the midpoint parallel to a transverse plane of the axis. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1An introducer needle is shown having a distal end with a sharp distal tip for piercing a target anatomy and a plurality of machined surfaces shaped for smooth advancement and retraction of a guidewire.

[0026] Figure 2 shows a coordinate system with a needle Figure 1 puncture needle.

[0027] Figure 3 The first transition section Figure 1 Cross section of the distal end of the puncture needle.

[0028] Figure 4 The second transition section shows Figure 1 Cross section of the distal end of the puncture needle.

[0029] Figure 5 Shown with Figure 1 An exemplary guide wire for use with a puncture needle.

[0030] Figure 6 Shows Figure 1 The beveled portion of the distal end of the puncture needle.

[0031] Figure 7 shows a Figure 5 Exemplary guide wires Figure 1 puncture needle.

[0032] Figure 8 Shows Figure 7 A side view of an introducer needle and guidewire, wherein the guidewire engages the inner bevel of the introducer needle.

[0033] Fig. 9 Shows Figure 8 Cross-sectional view of the puncture needle and guide wire.

[0034] Fig.10 Shows Figure 7 A side view of an introducer needle and guidewire, wherein the guidewire engages the outer bevel of the introducer needle.

[0035] Fig.11 An introducer needle having a longitudinal slot and a guidewire having alignment lugs according to a second exemplary embodiment are shown.

[0036] Fig.12 Shows Fig.11 The beveled edge of the alignment lug. DETAILED DESCRIPTION

[0037] The present invention may be further understood with reference to the following description and accompanying drawings, wherein like elements are represented by like reference numerals. An exemplary embodiment describes a device having a needle with a smooth surface to facilitate advancement or retraction of a guidewire without damaging the guidewire. An exemplary device may include a device for aligning the guidewire within the needle so that the guidewire interacts with a smooth abrasive surface rather than a sharper edge defined in the tip of the needle.

[0038] Figure 1 The distal end of a puncture needle 100 is shown, and the puncture needle 100 has a distal end 102 with a sharp distal tip 104 for piercing a target anatomical structure, and a plurality of machined surfaces shaped to facilitate smooth advancement and retraction of a guide wire 150 from the distal end 102 into the distal end 102. The needle 100 is formed as a hollow shaft 124, which is sized and shaped to receive the guide wire 150 slidably so that the guide wire 150 can extend distally from the distal tip 102 as will be understood by those skilled in the art. The needle 100 can be formed of any suitable material, such as nitinol alloy, cobalt chromium alloy, stainless steel, etc. The guide wire 150 can be configured to bend multiple times on a tortuous path that has been passed through, for example, a natural body cavity to enter a target tissue structure on an insertion device such as an endoscope. Additionally, the guide wire can be an anchoring guide wire having a shaped distal end that enables anchoring of tissue.

[0039] In this embodiment, if Figure 5 As shown, the guidewire 150 has a curved end 152 in its unconstrained state, which is preformed to present a curved shape with two curved sections 154, each of which is bent in the same direction of curvature through an angle of up to about 135 degrees, so that when unconstrained, the distal tip of the guidewire 150 points to a direction that is at an angle of up to about 270 degrees relative to the longitudinal axis of the portion of the guidewire 150 proximal to the curved end 152. However, guidewires with other curvatures may also be used. As will be understood by those skilled in the art, the guidewire 150 has sufficient flexibility so that when one or both of the curved portions 154 are withdrawn into the shaft 124, the curved end 152 can conform to the path of the interior extension of the hollow shaft 124. The guidewire 150 may have, for example, a nitinol core covered in a polymer coating.

[0040] When the curved end 152 of the guide wire 150 extends distally from the distal tip 102 of the needle 100, that is, when the curved end 152 is not constrained by the inner diameter of the shaft 124, the distal tip 156 of the guide wire 150 returns to its unconstrained state. However, the guide wire 150 as described herein is only for exemplary purposes, and any guide wire can be used with the puncture needle 100. For example, the guide wire can be bent and / or have more or less bends at different points in different curvature directions. It will be understood by those skilled in the art that the guide wire with significant curvature at its distal end is most likely to be damaged when it is extracted into a traditional needle, because the radial inner side of the curved end is dragged on the sharp end of the needle to re-enter the cavity of the needle. As will be understood by those skilled in the art, the guide wire with a preformed curved distal end is generally used as an anchoring guide wire. That is, this type of guide wire can be inserted into the target structure via a needle or other insertion device that keeps the curved distal end substantially straight. In addition, the guide wire can have any desired structure.

[0041] When the target structure has been entered, the guide wire 150 can be pushed out distally from the needle 100 (or the needle 100 can be withdrawn proximally on the guide wire 150) to release the curved end 152 to assume its curved configuration. In this curved state, the guide wire 150 can no longer pass proximally from the hole through which it entered the target tissue structure and is therefore anchored in the target structure. The needle 100 can then be withdrawn proximally on the guide wire 150, which can then be used to provide a channel for other therapeutic devices (e.g., stents, etc.) to be inserted into the target structure over the guide wire 150.

[0042] When the operation is completed, the needle 100 is again advanced distally over the guide wire 150 into the target structure. At this point, the guide wire 150 is withdrawn proximally into the needle 100, during which contact between the lumen of the needle 100 and the wall of the guide wire 150 constrains the guide wire to return to the passage of the lumen of the needle 100. The needle 100 with the guide wire received therein can then be withdrawn from the body. The needle of this embodiment is intended to minimize or eliminate damage to the guide wire during the process of withdrawing the guide wire proximally into the needle lumen.

[0043] The opening at the distal end 102 of the needle 100 is defined by a plurality of machined surfaces cut into the hollow shaft 118. The opening is defined by the first section 106, the second section 110, and the third section 116. Figure 2 As shown, the segment is defined in the following manner relative to a needle coordinate system having a longitudinal axis A, a first transverse axis B and a second transverse axis C, these axes defining a first longitudinal plane AC, a second longitudinal plane BC and a transverse plane AB.

[0044] The distal end 102 has a sharp distal tip 104 that penetrates tissue at the origin of the needle coordinate system, i.e., the most distal point of the puncture needle 100. In this embodiment, the opening at the distal end 102 of the needle 100 is substantially symmetrical with respect to the distal tip 104, so that the first segment, the second segment, and the third segment on either side of the AC plane are mirror images of each other. The first segment 106 is defined by a first cut extending proximally and laterally from the distal tip 104 into the cylindrical wall of the needle 100.

[0045] The first incision begins at the distal tip 104 at a first angle relative to the BC plane, the first angle being between about 0 and 10 degrees, i.e., substantially parallel or nearly parallel to the BC plane, and gradually steepens to a second angle relative to the BC plane at the first transition portion 108, as can be seen in FIG. Figure 1 As seen in Figure 8 For example, the second angle, i.e., the angle of the cut of the first segment 106 at the first transition 108 relative to the BC plane can be between about 20 and 50 degrees. Thus, the first cut creates a curved first segment 106 that progresses from a shallow angle at the distal end that is nearly parallel to the longitudinal axis of the needle 100 to a deeper angle relative to the longitudinal axis at the first transition 108. As described above, the first cut of this embodiment is substantially symmetrical on both sides of the distal tip 104.

[0046] The second section 110 is defined by a second cut extending proximally and laterally from the first transition portion 108 to a second transition portion 112 and a third cut extending only proximally, i.e., substantially parallel to the BC plane, from the second transition portion 112 to a third transition portion 114. The second cut is at a third angle relative to the BC plane, and the third angle remains substantially constant from the first transition portion 108 to the second transition portion 112. For example, the third angle, i.e., the angle of the second cut relative to the BC plane, can be between about 10 degrees and 30 degrees. It should be noted that the second cut and the third cut are reflected on both sides of the needle 100. Figure 3 A cross section of the needle 100 at the first transition portion 108 is shown in FIG. Figure 4 , a cross section of the needle 100 at the second transition portion 112 is shown, which is the same as the cross section of the needle 100 at the third transition portion 114 .

[0047] As will be appreciated by those skilled in the art, the first angle, the second angle, and the third angle may be different from the exemplary angles provided above without departing from the scope of the present invention. The shapes of the first segment 106 and the second segment 110 are configured to puncture or obtain tissue from a target site in vivo. Therefore, the edge of the needle 100 produced by the first incision, the second incision, and the third incision remains sharp.

[0048] The third section 116 is defined by a fourth cut extending proximally and laterally from the third transition portion 114. The fourth cut is parallel to the A axis throughout the cut, with a varying angle relative to the AC plane, thereby forming a substantially U-shaped chamber in the third section 116. The fourth cut begins at the third transition portion 114 at a fourth angle relative to the AC plane, which may start at about ~0 degrees, with the angle gradually increasing to ~90 degrees until the fourth cut reaches the midpoint 118, i.e., the farthest proximal point in the distal end 102 of the cut. The angle of the fourth cut at the midpoint is substantially parallel to the AB plane and orthogonal to the AC plane. It should be noted that the fourth cut is substantially symmetrical with respect to the AC plane. Without any further machining, the fourth cut will produce sharp edges on the inner and outer surfaces of the shaft 124.

[0049] During endoscopic procedures, such as those used to insert stents or rendezvous procedures, Figure 5 The guide wire shown, such as guide wire 150, can be introduced into the target anatomical space and pushed out distally from needle 100. This allows guide wire 150 to return to its unconstrained curved configuration, thereby anchoring it in the target space. After the operation has been completed and the guide wire 150 needs to be withdrawn from the body, the user inserts needle 100 over the guide wire 150 until the distal tip 104 of needle 100 enters the target space. Then, the user withdraws the curved end 152 of the guide wire 150 back into the distal end 102 of the needle 100. As described above, if the guide wire 150 is pulled back into the needle 100 in a manner that the guide wire 150 is dragged on a sharp tissue cutting surface, the guide wire 150 may be damaged.

[0050] To mitigate the above risks, in an exemplary embodiment, after making the first cut, the second cut, the third cut, and the fourth cut, the needle 100 is further machined. Figure 6 As shown, the distal end 102 has an outer bevel 120 to smooth the sharp edges on the outer surface of the third segment 116; and an inner bevel 122 to smooth the sharp edges on the inner surface of the third segment 116 to minimize the impact of contact between these surfaces and the guide wire 150. The radius of curvature of the outer bevel 120 and the inner bevel 122 can be in the range of about 0 "to 0.010". In addition, the outer bevel 120 and the inner bevel 122 each have a curvature of about 45 degrees to avoid creating new sharp edges. In another embodiment, the outer bevel 120 and the inner bevel 122 can be an outer diameter and an inner diameter, an outer chamfer and an inner chamfer, or an outer fillet and an inner fillet. In addition, the third segment 116 can have a combination of bevels, radii, chamfers, and fillets (e.g., the sharp edges of the outer surface are fillets, and the sharp edges of the inner surface are bevels).

[0051] Figure 7 A guide wire 150 is shown. Figure 1In the needle 100 , the curved end 152 of the guide wire 150 extends distally from the distal end 102 . Figures 8 to 10 1 shows an exemplary interaction of the guidewire 150 with the distal end 102 during the retraction of the guidewire 150. The guidewire 150 in this embodiment is bent around the B axis of the needle, thereby ensuring that when the guidewire 150 is withdrawn into the needle 100, it is pulled over the surface defined in the third section 116 of the distal end 102, rather than over the sharper surfaces of the first section 106 and the second section 110, respectively. Fig. 9 As can be seen in FIG. 1 , the guide wire 150 is pulled over the smooth inner bevel 122, thereby reducing the risk of the guide wire 150 being stripped during the retraction process. Fig.10 As can be seen in FIG. 1 , when the curvature radius of the guide wire 150 is very small, the interaction between the guide wire 150 and the inclined surfaces 120 , 122 increases, so that the guide wire 150 can also be pulled on the outer inclined surface 120 .

[0052] In order for the guidewire to contact only the beveled third segment 116 and not the sharp first segment 106 or second segment 110, it is necessary to ensure that the guidewire is properly rotationally aligned within the needle 100. In other words, during retraction, the curvature of the guidewire 150 must be oriented so that the curvature of the guidewire 150 extends generally within the AC plane and the guidewire 150 curves away from the side of the needle on which the distal tip 104 is formed. If the guidewire has a more complex curvature (e.g., a curvature extending in more than one plane), the user can rotate the guidewire 150 or the needle 100 relative to the other under ultrasound visualization so that the segment currently entering the needle 100 is oriented in the AC plane, as described above. Therefore, when the guidewire 150 enters the needle 100, the guidewire 150 will always contact the third segment 116.

[0053] The needle 100 and the guide wire 150 can have features for enhancing their visualization under ultrasound guidance, so that the surgeon can ensure that the proper alignment of the needle 100 and the guide wire 150 is achieved by monitoring the direction of the elements. For example, the needle 100 and the guide wire 150 can be formed of an echogenic material. However, retraction can also occur without direct visualization. Therefore, the proper alignment of the elements can be ensured in an alternative manner.

[0054] Figure 11 to Figure 12An introducer needle 200 is shown having a longitudinal slot 204 in its hollow shaft 202. The introducer needle 200 can be used with a guide wire 250 having a radially outwardly projecting lug 252 (e.g., welded or coated onto the guide wire 250) that is sized and shaped to travel in the longitudinal slot 204 during distal advancement and proximal retraction of the guide wire 250 from the needle 200. The lateral movement of the lug 252 is limited by the slot 204. In other words, the interaction between the lug 252 and the slot 204 maintains the guide wire 250 in a selected rotational alignment relative to the introducer needle 200 throughout the procedure.

[0055] In this embodiment, the slot 204 is closed at the distal end 206 of the needle 200. However, in another embodiment, the slot 204 can be open at the distal end 206. Thus, it can be ensured that the curvature of the guidewire 250 interacts only with the beveled portion of the needle 200. Those skilled in the art will appreciate that the slot can be curved in a manner corresponding to the curvature of a more complex guidewire shape to ensure that during the process of withdrawing the guidewire 250 into the needle 200, the distal end of the guidewire 250 is always rotated into the desired alignment relative to the needle 200.

[0056] In some procedures, after the guide wire 250 has been anchored in the target anatomical structure, the needle 200 is pulled proximally away from the guide wire 250. If the lug 252 is not designed to allow the needle 200 to pass thereon, the presence of the lug 252 can prevent such withdrawal of the needle 200. As will be appreciated by those skilled in the art, the lug 252 can be designed so that when the needle 200 is pulled proximally away from the guide wire 250, the lug 252 will be broken off. In another embodiment, the lug 252 can be designed to compress and pass through the distal end of the lumen of the needle 200 until it leaves the distal end 206 of the needle 200. Subsequently, the needle 200 can be slid proximally away from the guide wire 250 and removed from the body. For example, the lug 252 may have a ramp section 254 that facilitates folding on the leading edge of the lug 252 when reaching the distal end of the slot 204, so that when the needle 200 is pulled proximally on the guide wire 250, the lug 252 is folded on the cavity of the needle 200 and compressed therein when the lug passes under the portion of the needle 200 located distal to the distal end of the slot 204.

[0057] Those skilled in the art will appreciate that the above-described embodiments may be modified without departing from the concept of the present invention. It should also be understood that structural features and methods associated with one of the embodiments may be incorporated into other embodiments. Therefore, it should be understood that the present invention is not limited to the specific embodiments disclosed, but modifications are also encompassed within the scope of the present invention as defined by the appended claims.

Claims

1. puncture needle, the puncture needle include: a hollow shaft having a lumen sized and shaped to slidably receive a guidewire therein; and having a distal end, the distal end comprising an angled surface extending proximally and laterally from the sharp distal-most tip of the shaft to a beveled smooth region of the shaft, the beveled smooth region being proximal and transverse to the sharp tip, the beveled smooth region comprising an outer bevel on the outer surface of the shaft and an inner bevel on the inner surface of the shaft, and the beveled smooth region being positioned to slidably engage the guide wire extending distally from the distal end of the needle so that when the guide wire is proximally retracted into the needle, the beveled smooth region slidably engages the guide wire to minimize wear on the guide wire; wherein the shaft comprises a feature extending along a distal portion thereof, the feature being configured to mechanically engage a corresponding feature of a guide wire inserted therein to maintain the guide wire in a desired rotational orientation relative to the needle so that the guide wire contacts only the beveled smooth region.

2. The puncture needle of claim 1 , wherein the distal end of the shaft includes a sharp cutting surface extending proximally from the sharp tip, and the beveled smooth area is positioned so that when a guide wire extending from the distal end of the needle along a bend is retracted into the needle in a desired direction relative to the needle, a surface of the guide wire forming a radial inner surface along the bend contacts the beveled smooth area of ​​the needle.

3. The puncture needle according to any one of claims 1 to 2, wherein the distal end of the shaft includes a first sharp cutting surface extending from the distal-most tip to a first transition portion and a second sharp cutting surface extending from the first transition portion to a second transition portion, the first sharp cutting surface extending at the distal-most tip at a first angle relative to a longitudinal plane of the shaft and bending at the first transition portion to a second angle relative to the longitudinal plane of the shaft, the second sharp cutting surface having a third angle relative to the longitudinal plane of the shaft.

4. The puncture needle of claim 3, wherein the distal end of the shaft comprises a third sharp cutting surface extending from the distal-most tip to a third transition portion and a fourth sharp cutting surface extending from the third transition portion to a fourth transition portion, the third sharp cutting surface extending at a fourth angle relative to a longitudinal plane of the shaft at the distal-most tip and bending to a fifth angle relative to the longitudinal plane of the shaft at the third transition portion, the fourth sharp cutting surface extending at a sixth angle relative to the longitudinal plane of the shaft.

5. The puncture needle of claim 4, wherein the first sharp cutting surface and the second sharp cutting surface are substantially symmetrical with respect to the third sharp cutting surface and the fourth sharp cutting surface relative to a mid-plane of the needle.

6. The puncture needle of claim 3, wherein the first angle is within a first range of 0 to 10 degrees, the second angle is within a second range of 20 to 50 degrees, and the third angle is within a third range of 10 to 30 degrees.

7. The puncture needle of any one of claims 1 to 2, wherein the bevel smooth region is defined by a U-shaped surface having a midpoint proximal to and transverse to the sharp tip, the U-shaped surface having a curvature at the midpoint parallel to a transverse plane of the axis.

8. The puncture needle according to any one of claims 1 to 2, wherein the shaft is formed of one of a nitinol alloy, a cobalt-chromium alloy, and stainless steel.

9. The introducer needle of claim 1, wherein the feature of the shaft comprises a slot extending along a portion of the length of the needle, the needle being configured to receive a lug extending radially from the guidewire.

10. A puncture needle assembly, the puncture needle include: an anchoring guidewire, the anchoring guidewire comprising a first orientation feature; as well as A puncture needle, the puncture needle comprising a hollow shaft having a cavity sized and shaped to slidably receive a guide wire therein; and having a distal end, the distal end comprising a cutting surface, the cutting surface extending proximally and laterally from the sharp distal-most tip of the shaft to a beveled smooth region of the shaft, the beveled smooth region being proximal to and transverse to the sharp tip, the beveled smooth region comprising an outer bevel on the outer surface of the shaft and an inner bevel on the inner surface of the shaft, and being positioned to slidably engage the guide wire extending distally from the distal end of the needle, so that when the guide wire is proximally retracted into the needle, the beveled smooth region slidably engages the guide wire to minimize wear on the guide wire, the puncture needle also comprising a second orientation feature extending along its distal portion, the second orientation feature being configured to mechanically engage the first orientation feature to maintain the guide wire in a desired rotational orientation relative to the puncture needle so that the guide wire contacts only the beveled smooth region.

11. The introducer needle assembly of claim 10, wherein the second orientation feature comprises a slot extending along a portion of the length of the needle and the first orientation feature comprises a lug projecting outwardly from the guidewire.

12. The puncture needle assembly of claim 11, wherein the lug has a ramp section to facilitate engagement of the shaft and the lug such that when the needle is retracted proximally over the guide wire, the ramp engages the distal end of the slot causing the lug to fold over and pass through the needle until the lug has disengaged from the distal end of the needle.

13. The puncture needle assembly according to any one of claims 10 to 11, wherein the second directional feature comprises a narrow groove extending along a portion of the length of the needle, and the first directional feature comprises a lug protruding outward from the guide wire, the lug being configured to be cut off from the guide wire when the needle is withdrawn proximally on the guide wire.

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