HK1018224B - Directional catheter - Google Patents

Description

Guide cannula

Technical Field

The invention relates to a cannula, in particular to a medical guide cannula.

Background

In recent years, there has been significant progress in the placement of intraluminal devices such as stents and grafts and in the performance of intraluminal procedures. In many such placements and procedures, a guidewire must initially be placed into a designated portion of the lumen of a predetermined vessel or duct, such as a blood vessel. Once the initial guidewire is in place, a cannula or other tubular device may be placed over the guidewire and used to deliver another guidewire, replacement, endoscope or surgical instrument into the intended vessel or duct.

There are a number of methods available for placing a guidewire into the lumen of a branched lumen. One method is to place a relatively rigid guidewire in a body lumen and then place a cannula therethrough, typically angled, curved or of some other configuration, in the region of its proximal end. After the cannula is placed in the desired position over the rigid guidewire, the rigid guidewire is withdrawn so that the region of the cannula adjacent the end assumes its usual configuration. A thin guide wire may then be fed through the cannula and in the direction guided by the cannula. The thin guide wire is preferably flexible enough to allow it to be introduced in the direction in which the cannula is guided, while avoiding the situation in which the thin guide wire causes structural changes in the cannula. Since the first rigid guidewire must be removed first to allow thin guidewire insertion, it is clinically undesirable to reinsert the rigid guidewire at a later time, if desired. In addition, withdrawal of the rigid guidewire results in loss of control over where the cannula is located and often places the cannula in an undesirable position, requiring reinsertion of the rigid guidewire to correct the position. The strength of the cannula further limits the rigidity of the thin guidewire or another second cannula that may be subsequently inserted through the cannula, which may further complicate the subsequent placement of one guidewire through the bifurcated body lumen.

An example of a guide cannula is described in U.S. patent 4898577 to Badger et al. The Badger guide cannula includes a single elongate shaft having a distal portion that is bendable, the angle of bending of the distal portion relative to the elongate shaft being controllable by a physician-manipulable pull wire extending from the distal end back through the lumen to the proximal end of the cannula. When the distal section is at the desired bend angle, the guidewire is fed through the cannula.

Another type of guide cannula is known as a twistable cannula. An emutexample of such a cannula is described in australian patent document AU-a-32951/95 to Lundquist. The Lundquist cannula also has a single elongate shaft with a bendable portion that can be manipulated by the physician to bend the end of the cannula to guide the guidewire in a predetermined direction therethrough.

Even with steerable or torqueable cannulas, physicians often encounter problems in achieving directional placement of guide wires and cannulas in body lumens, particularly when it is desired to directionally introduce a guide wire into a main lumen branch. Conversely, there is also the problem of the guidewire entering the branch lumen rather than remaining in the main lumen.

One example is the tendency of a guidewire to be oriented into the lumen of a branch during placement of an intraluminal graft into a patient to effect bridging and closure of an aneurysm at the aorta, ilia, or other artery. The present invention relates to an optional guiding cannula which can be used for placement of a guidewire or cannula within a body vessel or lumen.

Disclosure of Invention

The inventors of the present invention have determined that a substantial advantage over conventional methods can be achieved by placing a primary guidewire in a body lumen and then using the primary guidewire as a platform to insert and support a cannula that can be used to guide an auxiliary guidewire and/or cannula in a lateral direction relative to the position of the primary guidewire.

Accordingly, a first aspect of the present invention comprises an intraluminal catheter for insertion into a lumen of a body, the catheter having a first elongate tubular member defining a first lumen, the tubular member having a trunk portion and having a support means on an outer surface thereof, the support means being adapted to slide over a main guidewire disposed in the lumen. The first elongate tubular member has a tip portion that is deflectable relative to the position of the main portion, the tip portion being used to guide an auxiliary guidewire through the first lumen and into the body lumen in a direction transverse to the position of the main guidewire.

The support means on the intraluminal catheter is configured such that when the auxiliary guidewire is fed through the first lumen, the intraluminal catheter is supported by the main guidewire which has been placed within the body lumen. The use of such a cannula eliminates the need to withdraw a rigid guide wire prior to insertion of the auxiliary guide wire. In addition, such support during placement of the auxiliary guidewire ensures that the guidewire is disposed in a direction that is as intended by the physician, transverse to the position of the primary guidewire.

In one embodiment, the support device includes a second elongate tubular member alongside the first elongate tubular member, the second elongate tubular member being at least as long as the first elongate tubular member. The cannula can also have a second or more lumens.

The tip portion may have a surface that is angled away from the location of the first lumen or extension thereof. Preferably, the ramp is located in the first lumen and the first tubular member has an aperture therein which is diametrically opposed to the ramp so that the auxiliary guide wire will be bent by the ramp as it passes through the first lumen and then through the aperture. The ramp may be proximate a free end of the first tubular member.

In another embodiment, the cannula may further include a means for controlling the bending of the position of the tip portion relative to the main portion.

In yet another embodiment, the control device may include a steering wire extending along the cannula and secured to the tip portion. As the steering wire is retracted relative to the cannula, it bends relative to the tip portion of the main body portion. The steering wires may be located in other lumens of the cannula, if desired.

The main portion of the first tubular member is generally straight in configuration and the tip portion is generally arcuate in configuration. The cannula also has an outer sleeve which is longitudinally movable relative to the first tubular member between a first position in which the outer sleeve surrounds and thereby straightens the tip portion, and a second retracted position in which the tip portion is free and assumes its generally arcuate configuration.

In this specification, the general structure of the first tubular member of the invention is the configuration that the tubular member has when the cannula is outside the body and the overtube is in the second retracted position relative to the first tubular member.

In another embodiment, the trunk portion is straight in configuration and the tip portion may be preformed at an angle to the trunk portion. The cannula has an outer sleeve which is longitudinally movable relative to the first tubular member between a first position in which the outer sleeve surrounds the tip portion and thereby straightens the tip portion, and a second retracted position in which the tip portion is free and assumes a preset angle with respect to the main portion.

The tip portion of the cannula is preferably made of a shape memory material that will assume a generally curved or angled configuration when the cannula is in a desired position within the body lumen and the outer cannula is in a retracted position relative to the first tubular member.

The cannula is preferably dimensioned so that it can be inserted into a body lumen from a 6cm (18French) thick introducer tube.

According to a second aspect of the invention, the invention comprises a set of instruments for guiding an auxiliary guidewire in a lateral direction relative to the position of a main guidewire placed in a body lumen. The kit includes an intraluminal catheter having a first elongated tubular member with a first lumen. The tubular member has a main portion and has a support means on its outer surface adapted to slide over a main guidewire placed in a body lumen. An auxiliary guidewire is positioned in the first lumen and the first tubular member has a tip portion that is deflectable relative to the position of the main portion and that guides the auxiliary guidewire in a transverse direction through the first lumen.

In one embodiment of the second aspect of the invention, an auxiliary cannula may be placed over the auxiliary guide wire in the first lumen, the auxiliary cannula having an adjustable distal end, a pre-angled or end that may be of a generally arcuate configuration. In another embodiment, the auxiliary cannula may have the features of the intraluminal cannula described in the first, second or third aspect of the invention.

Another aspect of the invention includes a guidewire bending cannula system comprising:

a bent cannula defining an axis and an axially extending first guidewire lumen;

a first elongate tubular member defining a lumen separate from the first guidewire lumen, the member having a flexible distal end, the first elongate tubular member extending axially substantially along the length of the first guidewire lumen in a first, non-flexed configuration, the distal end of the first elongate tubular member being relatively movable with respect to the first guidewire lumen so as to flex transversely with respect to the cannula axis to assume a second, flexed configuration;

a first guidewire positioned in the first guidewire lumen; and

a bending wire, being more flexible than the first wire, is sized to be placed in and through the lumen of the first elongate tubular member and to be bent at its distal end into a second bent state, thereby extending the distal end laterally relative to the cannula shaft.

Another aspect of the invention includes a system for delivering a guidewire to a contralateral leg of a bifurcated implant, the bifurcated implant having a tubular trunk portion branching into two tubular legs at a bifurcation point, the ipsilateral and contralateral legs, respectively, the system comprising:

a cannula defining a shaft and an axially extending first guidewire lumen; the cannula includes a first elongate tubular member defining a tubular member lumen therein, the member having a flexible distal end operable in a first, non-bent state in which the first elongate tubular member extends substantially axially along the length of the first guidewire lumen and a second, bent state in which the flexible distal end is bent transversely relative to the cannula axis;

a first guidewire positionable through the ipsilateral leg within the bifurcated implant and over which the cannula is positionable, the distal end of the first elongate tubular member being adjacent the bifurcation point, and

a bending wire, more flexible than the first wire, is sized to be disposed within and through the tubular member lumen of the first elongate tubular member and is in a second bent state such that the distal end of the first elongate tubular member extends laterally relative to the cannula axis into the opposite leg.

In accordance with a further aspect of the present invention, the present invention includes a method for guiding an auxiliary guidewire in a lateral direction relative to a position of a main guidewire disposed in a lumen of a human body, the method comprising the steps of:

(a) placing a main guidewire in a body lumen;

(b) introducing a support means for intraluminal intubation, as defined herein, over the main guidewire and into the body lumen;

(c) an auxiliary guidewire is passed through the first lumen of the intraluminal catheter such that the auxiliary guidewire is transversely guided into the body lumen by the bendable tip portion.

In a preferred embodiment of this aspect of the invention, an auxiliary cannula is first passed through the first lumen and guided in a transverse direction. Then an auxiliary guide wire is inserted through the auxiliary guide wire

FIG. 8 is a cross-sectional view of the tip portion of a third embodiment of the intraluminal catheter of the present invention;

FIG. 9 is a longitudinal cross-sectional view of one embodiment of a possible bifurcated implant used in the method described in FIGS. 2a-i, having been mounted on a delivery cannula; and

fig. 10 is a longitudinal cross-sectional view of one embodiment of a tubular implant mounted on a delivery cannula used in the method described in fig. 2 a-i.

Detailed Description

The invention is applicable to any surgical procedure requiring the introduction of a guide wire into a body lumen, including the aorta, renal arteries and iliac arteries, for example, whether the surgical procedure is the placement of an intraluminal implant or other surgical procedure.

The present invention is described below with reference to an example of placing an intraluminal implant into a patient to effect the bypass and closure of an aortic aneurysm. Other examples for use with the present invention will be readily apparent to those skilled in the art.

As seen in fig. 1, the aorta 10 bifurcates into the right and left iliac arteries 12, 13. The aortic aneurysm 14 is located between the renal arteries 15, 16 and extends down to the left iliac artery 13. One method of bridging the aneurysm 14 is to use a trouser-shaped implant 17 which provides a pair of bifurcated short tubular extensions 19, 19a which are connected to tubular implants 17a, 17b which extend down to the iliac arteries 12, 13, respectively. Such a trouser implant is described in Australian patent document AU-A-78035/94, which is incorporated herein by reference.

The method of placing an intraluminal implant will now be described with reference to figures 2 a-i. In performing this procedure, an incision is made to expose a femoral artery (ipsilateral) that is removed from the respective iliac artery, and a 0.889 mm (0.035 inch) diameter, soft-topped, flexible guidewire is inserted using the Seldinger needle technique and passed sequentially through the femoral and iliac arteries 12 and into the aorta 10, thus passing through the aneurysm 14. A 2.67cm (8French) thick hemostatic tube was then introduced through the guidewire to control bleeding. An angiographic cannula is then introduced to angiographically visualize the patient's renal arteries 15, 16 and other relevant anatomical structures.

An AES (Amplatz extra stiff) guidewire 23 (0.889 mm in diameter) is then passed through the angiographic cannula into the aorta 10. The rigid guidewire 23 remains in place after the angiographic cannula is withdrawn. A preferably 6cm (18French) thick cannula 21 is then fed into the aorta 10 over the rigid guidewire 23 (see FIG. 2 a). A balloon catheter 24 is then fed into the cannula 21 over the rigid guidewire 23.

As shown in fig. 9, the balloon catheter 24 is previously assembled with a trouser implant 17 having a crotch point 17c, a ipsilateral extension 19 and a contralateral extension 19 a. As shown in greater detail in Figs. 3 and 4, the cannula 24 has a first elongate tubular member 52 and a second elongate tubular member 51 adapted to be passed over the rigid guidewire 23 and to support the cannula 24 in the intraluminal implant 17. Located within the first elongated tubular member 52 is an auxiliary guidewire 26 sheathed by a thin auxiliary cannula 26a which extends upwardly in the first direction against the ipsilateral extension 19, along with the end of the first elongated tubular member 52 just above the bifurcation point 17 c.

After the balloon catheter 24 is properly positioned in the aorta 10, the sleeve 21 is partially withdrawn leaving the implant 17 free so that the balloon 20 can be inflated (see fig. 2 b). Inflation of the balloon 20 expands the upstream end of the first implant 17 so that it conforms to the aortic wall above the aneurysm but downstream of the renal arteries 15, 16. The length of the first implant 17 is such that the short tubular extensions 19, 19a are located entirely within the aorta 10. Next, the balloon 20 is deflated, but the balloon catheter 24 is temporarily left in place (see fig. 2 c). The deflation of balloon 20 allows blood to flow downward and expands implant 17 and tubular extensions 19, 19 a.

When the first implant 17 is in place, the guidewire 26 needs to be extended down to the left iliac artery 13. In the illustrated example, this is accomplished by guiding the auxiliary cannula 26a through the lumen of the first elongate tubular member 52 so that it encounters the ramp surface 54, is deflected laterally away from the position of the first elongate tubular member, and passes through the aperture 50 in the first elongate tubular member opposite the ramp surface 54. The proximal tip region of cannula 26a is generally in an angled or arcuate configuration with respect to the straight configuration of the remainder of cannula 26 a.

The physician may pass cannula 26a through aperture 50 as desired and then guide wire 26 through cannula 26a and into the left iliac artery 13 as depicted in fig. 2 c. As depicted in FIG. 4, the cannula 24 may also have an inflatable balloon 100 adjacent the end 55 of the first elongate tubular member 52, which balloon 100 is capable of being inflated when the cannula 24 is in place to further secure the cannula 24 in place and occlude the right iliac artery 12. Thus, when the guidewire 26 is introduced into the left iliac artery 13, blood flow is caused to flow down into the left iliac artery 13.

The proximal tip portion of cannula 26a, in addition to the generally arcuate or angled configuration it is readily envisioned that it can be modified from that described and thus it has the characteristics of cannula 24 or cannulae 60 and 70 as will be described in greater detail below. For example, the cannula 26a can also have first and second elongate tubular members with the second elongate tubular member surrounding the guidewire 26 and the first elongate tubular member having a guide means for guiding a further guidewire through the first elongate tubular member in a predetermined direction. Such a cannula may be used during applications that ultimately require a guidewire to be introduced from the left iliac artery 13 into the corresponding left femoral artery.

Fig. 5-8 depict an alternate embodiment of an intraluminal catheter of the present invention, one of which is the catheter 60 of fig. 5-7. The cannula 60 has a first elongated tubular portion having a main portion 65 which generally assumes a relatively straight configuration and an apical portion 66 (made of shape memory material) which generally assumes an arcuate configuration. Although the tip portion 66 is depicted as generally presenting an arcuate configuration, it is readily envisioned that the angled configuration may be pre-angled if it is more suitable for the application of the cannula 60. The cannula may also have a second elongate tubular member 61 whereby the cannula can slide over a guide wire, such as the rigid guide wire 23 used in the example described in figures 2a-i, to act as a support means for the cannula. The cannula also has a sleeve 62 which is relatively movable along the cannula between a first position in which the sleeve surrounds the first and second elongate tubular members 63, 61 (as depicted in figure 5) and a second retracted position in which the tip portion 66 is free and assumes its normal configuration (as depicted in figures 6 and 7). If used for placement of an intraluminal implant such as described in fig. 2a-i, implant 17 is assembled with cannula 60 so that tip portion 66 is located just above bifurcation point 17 c. When the cannula 60 is in a predetermined position in the artery 10, the implant 17 is positioned as described above. The sleeve 62 is then retracted relative to the tip portion 66, thereby causing the tip portion 66 to assume its generally arcuate configuration. The guidewire 26 is then introduced through the first elongate tubular member so as to exit the tip portion 66 and enter the left iliac artery 13 in a predetermined direction.

Although only the guidewire 26 is depicted as being introduced through the tip portion 66 in fig. 5-7, it is readily contemplated that an auxiliary cannula, such as auxiliary cannula 26a, may be used in conjunction with the cannula 60, as may be the relationship between the auxiliary cannula and the cannula 24.

The cannula, generally designated 70 in fig. 8, has many of the features of the cannula 60 except that the orientation of its tip portion 66 relative to its trunk portion 65 is controlled by the steering wires 71 of the physician. The control wire is secured to the tip portion 66 and passes back through another lumen 72 in the cannula 70. As with the other embodiments described, the guidewire 26 is guided through the tip portion 66 and towards the left iliac artery 13 in the desired direction.

The guidewire 26 is preferably constructed of a non-intertwined nitinol alloy material. If desired, the guidewire may have an orifice adjacent its tip, such as an inflatable balloon 74 (see FIG. 2c) (which may be inflated by passing a fluid, such as air, along a lumen in the guidewire 26). The purpose of the choke is to help the guidewire 26 be carried by the bloodstream and guided into the left iliac artery 13.

As described above, if desired, a further cannula having the features of one embodiment of the present invention may be fed over the guidewire 26 to assist in placement of the further guidewire into another lumen branching off the left iliac artery 13.

An advantage of the present invention is that, in addition to better control of placement of a guidewire into the lumen, the positioning of the cannula within the lumen by the primary guidewire 23 provides suitable support for the auxiliary guidewire 26 passing through the cannula into the branch lumen.

When the guidewire 26 is properly placed in the left femoral artery, an ostomy can be performed on the femoral artery that is clamped laterally and an arteriotomy has been performed. If the guidewire 26 has been introduced entirely into the contralateral femoral artery, the guidewire 26 can simply be pulled back through the incision or puncture made in the artery. If the guidewire 26 has not been fully introduced along the femoral artery, the guidewire 26 may be captured by feeding a snare or similar device to the contralateral femoral artery and withdrawn by pulling it to the puncture or incision site. Once the guidewire 26 has been removed, a cannula 27 is fed against the guidewire 26 and through the contralateral femoral artery until the cannula is within the first implant 17 and at least to the tip of the contralateral tubular extension 19 a. The guidewire 26 is then withdrawn and a rigid guidewire 30 is inserted into the cannula 27 through the contralateral femoral artery. The cannula 27 is then removed and a cannula sleeve 21a and dilator sleeve are fed over the rigid guidewire 30 (see fig. 2 e).

A second balloon catheter 24a, assembled with a second tubular implant 17b, is then fed through the catheter sleeve 21a until its upper end is just inside the contralateral tubular extension 19a and its lower end is just inside the left iliac artery 13, as shown in fig. 10. The balloon 20a on the cannula 24a is inflated so that the upper end of the implant 17b frictionally engages the contralateral tubular extension 19a (see fig. 2 f). Inflation of balloon 20a over cannula 24a supports implant 17 during withdrawal of first balloon-like cannula 24 from right iliac artery 12, and then balloon 20a is deflated and cannula 24a remains in place to support implants 17, 17b at aorta 10 during subsequent placement of a third implant 17 a.

The cannula sleeve 21a is then removed (see fig. 2f and 2g) and a third balloon cannula (which may be the same as that described in fig. 10) assembled with a tubular implant 17a is fed into the sleeve 21 over the guidewire 23. The cannula is advanced until its upper end is in the same side extension 19, and the cannula is seated as part of the sleeve 21 is pulled back. The third implant 17a, placed on the third balloon catheter, is then pushed forward until its upper end enters and contacts the ipsilateral extension 19 and its lower end enters and contacts the upper right iliac artery 12 (see fig. 2 h).

The rigid guide wires 23 and 30 are now withdrawn, the contralateral incision or puncture is closed, a second angiographic examination is then performed, and if the implants 17, 17a and 17b are properly positioned and functioning, the cannula 21 is withdrawn and the incision in the right thigh is closed (see fig. 2 i). The result is an effective trouser implant that completes the aneurysm bypass as shown in figure 2 i.

The procedure may be performed using general anesthesia, epidural anesthesia, or, where appropriate, local anesthesia alone.

It will be obvious to those skilled in the art that changes and/or modifications may be made in the particular embodiments of the invention shown without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims (19)

1. An intraluminal catheter for insertion through a body lumen, the catheter having a first elongate tubular member defining a first lumen, the tubular member having a trunk portion and on an outer surface thereof support means adapted to slide over a main guidewire positioned within the lumen, characterised in that the first elongate tubular member has a tip portion which is bendable with respect to the position of the trunk portion for guiding an auxiliary guidewire through the first lumen and into the body lumen in a direction transverse to the position of the main guidewire.

2. A cannula according to claim 1, wherein the support means comprises a second elongate tubular member arranged alongside the first elongate tubular member.

3. The cannula of claim 2, wherein the second elongate tubular member is at least as long as the first elongate tubular member.

4. A cannula according to any of the preceding claims, wherein the tip portion further has a surface which is at an angle to the first lumen or extension thereof, such that the auxiliary guidewire when passing through the first lumen will encounter said angled surface and be bent laterally at a position offset from the first lumen or extension thereof.

5. The cannula of claim 4, wherein the angled surface is located within the first lumen and the first elongate tubular member has an aperture opposite the angled surface such that the auxiliary guidewire will be bent by the angled surface through the aperture when passing through the first lumen.

6. A cannula according to claim 4, wherein said angled surface is proximate the free end of the first elongate tubular member.

7. A cannula according to any of claims 1-3, further comprising a means for controlling bending of the position of the tip portion relative to the trunk portion.

8. The cannula of claim 7, wherein the control device includes a control wire extending along the cannula and secured to the tip portion, the control wire being withdrawn relative to the cannula to bend the position of the tip portion relative to the main portion.

9. The cannula of claim 8, wherein the control wire is located within another lumen of the cannula.

10. A cannula according to any of claims 1-3, wherein the main portion assumes a generally straight configuration and the tip portion assumes a generally curved configuration, the cannula further having a sleeve longitudinally movable relative to the first elongate tubular member between a first position in which the sleeve surrounds and thereby straightens the tip portion and a second retracted position in which the tip portion is free and assumes its generally curved configuration.

11. A cannula according to any of claims 1-3, wherein the main portion is of generally straight configuration and the tip portion is preformed at an angle to the main portion, said cannula having a sleeve which is longitudinally movable relative to the first elongate tubular member between a first position in which the sleeve surrounds and thereby straightens the tip portion and a second retracted position in which the tip portion is free and assumes a predetermined angle to the main portion.

12. The cannula according to any of claims 1-3, wherein the cannula can be guided into a body lumen through a 6cm thick guide cannula.

13. A kit for guiding an auxiliary guide wire in a direction transverse to the position of a main guide wire located in a body lumen, said kit comprising an intraluminal catheter having a first elongated tubular member defining a first lumen, said tubular member having a main portion and a support means on an outer surface thereof, the support means being adapted to slide over the main guide wire located in the body lumen, said auxiliary guide wire being located in the first lumen, characterized in that the first elongated tubular member has a tip portion which is bendable relative to the main portion and which guides the auxiliary guide wire in a transverse direction through the first lumen.

14. The kit of claim 13, wherein an auxiliary cannula is placed over said auxiliary guidewire positioned within the first lumen.

15. The kit of claim 14, wherein said auxiliary cannula has a controllable distal end.

16. The device as claimed in claim 14, wherein said auxiliary cannula has a tip portion with a preformed angle.

17. The kit of claim 14, wherein said auxiliary cannula assumes a generally arcuate configuration.

18. A guidewire bending cannula system comprising:

a bent cannula defining an axis and an axially extending first guidewire lumen;

a first elongate tubular member defining a lumen separate from the first guidewire lumen, the member having a flexible distal end, the first elongate tubular member extending axially substantially along the length of the first guidewire lumen in a first, non-flexed configuration, the distal end of the first elongate tubular member being relatively movable with respect to the first guidewire lumen so as to flex transversely with respect to the cannula axis to assume a second, flexed configuration;

a first guidewire positioned in the first guidewire lumen; and

a bending wire, being more flexible than the first wire, is sized to be placed in and through the lumen of the first elongate tubular member and to be bent at its distal end into a second bent state, thereby extending the distal end laterally relative to the cannula shaft.

19. A system for delivering a guidewire to a contralateral leg of a bifurcated implant, the bifurcated implant having a tubular trunk portion branching into two tubular legs at a bifurcation point, the ipsilateral and contralateral legs, respectively, the system comprising:

a cannula defining a shaft and an axially extending first guidewire lumen; the cannula includes a first elongate tubular member defining a tubular member lumen therein, the member having a flexible distal end operable in a first, non-bent state in which the first elongate tubular member extends substantially axially along the length of the first guidewire lumen and a second, bent state in which the flexible distal end is bent transversely relative to the cannula axis;

a first guidewire positionable through the ipsilateral leg within the bifurcated implant and over which the cannula is positionable, the distal end of the first elongate tubular member being adjacent the bifurcation point, and

a bending wire, more flexible than the first wire, is sized to be disposed within and through the tubular member lumen of the first elongate tubular member and is in a second bent state such that the distal end of the first elongate tubular member extends laterally relative to the cannula axis into the opposite leg.