DELIVERY CATHETER WITH FIXED GUIDEWIRE AND BEVELED ELLIPTICAL PORT

Abstract

A catheter includes a catheter body having a proximal end, a beveled distal end, and a lumen therethrough. The beveled distal end defines an elliptical port for releasing contrast or other media through the lumen and from the elliptical port. The catheter may also be used delivering devices or for aspirating or extracting materials from the vasculature or other body lumens. A fixed guidewire extends distally from the distal end of the catheter body, typically from the distal-most edge of the elliptical port. The fixed wire is typically malleable so that it can be manually formed into a desired shape. The elliptical port may be flat or concave.

Claims

1. A diagnostic or therapeutic catheter comprising: a catheter body having a proximal end, a beveled distal end, and a lumen therethrough, wherein the beveled distal end defines an elliptical port configured to release a radiopaque medium infused through the lumen, wherein the elliptical port defines a side profile that is concave.

2. The diagnostic or therapeutic catheter as in claim 1, wherein the side profile of the elliptical port has a slope that is non-planar.

3. The diagnostic or therapeutic catheter as in claim 1, wherein the side profile of the elliptical port has a proximal end and a distal end, and a slope of the side profile decreases towards the distal end thereof.

4. The diagnostic or therapeutic catheter as in claim 1, wherein the distal end of the elliptical port forms a trough.

5. The diagnostic or therapeutic catheter as in claim 1, further comprising a guidewire configured to extend distally from the beveled distal end of the catheter body.

6. The diagnostic or therapeutic catheter as in claim 1, wherein the guidewire is a fixed guidewire that is secured to the catheter body.

7. The diagnostic or therapeutic catheter as in claim 6, wherein the fixed guidewire is embedded eccentrically in the beveled distal end of the catheter body.

8. The diagnostic or therapeutic catheter as in claim 1, wherein the beveled distal end of the catheter body and an embedded proximal portion of the fixed wire together form a trough which extends from the elliptical port.

9. The diagnostic or therapeutic catheter as in claim 6, wherein the beveled distal end of the catheter body terminates in a distal tip adjacent to a distal-most edge of the elliptical port and wherein the fixed guidewire extends distally from the distal tip.

10. The diagnostic or therapeutic catheter as in claim 6, wherein the fixed guidewire is malleable so that it can be manually formed into a desired shape.

11. The diagnostic or therapeutic catheter as in claim 1, wherein the elliptical port is further configured to deliver other devices or serve as a conduit for extracting material through the lumen.

12. The diagnostic or therapeutic catheter as in claim 6, wherein the fixed guidewire is embedded in a length of the beveled distal end of the catheter body of 25 mm or less with the remainder of the length of the catheter body being free of the fixed guidewire.

13. The diagnostic or therapeutic catheter as in claim 12, wherein the fixed guidewire is embedded in a length of the beveled distal end of the catheter body in the range from 1 mm to 10 mm.

14. A method for performing angiography, said method comprising; providing an angiography catheter having a catheter body having a proximal end, a beveled distal end, and a lumen therethrough, wherein the beveled distal end defines an elliptical port configured to release a radiopaque medium infused through the lumen, and a guidewire therethrough, wherein the elliptical port defines a side profile that is concave; advancing the catheter through an aorta; torqueing the catheter body while advancing to steer the guidewire into a branch vessel; and delivering contrast media through the lumen into the branch vessel.

15. The method for performing angiography as in claim 14, further comprising introducing the angiography catheter through an access sheath into the aorta without an introducer.

16. The method for performing angiography as in claim 14, further comprising extracting material through the lumen.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1 shows a prior art MP catheter in a straight section of an artery with a distal tip of the catheter urged against the arterial wall. A magnification in the lower left corner shows deformation of the wall by the catheter tip.

[0027] FIG. 2 illustrates a first embodiment of a distal end of an angiography catheter having a straight or flat elliptical contrast release and/or aspiration port constructed in accordance with the principles of the present invention.

[0028] FIG. 3 illustrates a second embodiment of a distal end of an angiography catheter having a concave or scalloped elliptical contrast release and/or aspiration port constructed in accordance with the principles of the present invention.

[0029] FIG. 4 illustrates an exemplary proximal end or hub of an angiography catheter having a finned or torpedo luer fitting constructed in accordance with the principles of the present invention.

[0030] FIG. 5 illustrates connection of the luer fitting of FIG. 4 to a source of saline with a septum for injecting contrast medium into the angiography catheter.

[0031] FIG. 6 illustrates introduction of an angiography catheter of the present invention to a left common carotid artery via an innominate artery in a bovine aortic arch type.

[0032] FIG. 6A illustrates introduction of an angiography catheter of the present invention to a left common carotid artery similarly to FIG. 6 where the guidewire tip has a more aggressive bend.

[0033] FIG. 6B illustrates introduction of an angiography catheter of the present invention through the access sheath by piercing the valve without the need for an introducer.

[0034] FIG. 7 illustrates a third embodiment of a distal end of an angiography catheter constructed in accordance with the principles of the present invention having a quill-shaped proximal end embedded in the distal tip of the catheter body.

[0035] FIGS. 7A-7D are cross-sectional views taken along lines 7A-7A, 7B-7B, 7C-7C, and 7D-7D, respectively, of FIG. 7.

DETAILED DESCRIPTION OF THE INVENTION

[0036] The invention is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.

[0037] FIG. 2 illustrates a first exemplary catheter 10 having a catheter body 12 with a beveled distal tip 14 with fixed guidewire 20 extending distally from an elliptical port 16 at the distal end of a central lumen 18. While particularly intended for use as an angiography catheter, the catheters of the present invention may also find use in other diagnostic procedures, particularly those relying on intravascular deliver of contrast media or other substances, as well as in therapeutic interventions, such as aspiration of blood clots and/or foreign bodies or as a conduit for infusion of drug and/or and other substance delivery.

[0038] Exemplary dimensions for the catheter 10 when used for angiography are set forth in Table 1 below.

TABLE-US-00001 TABLE 1 Exemplary Dimensions for Angiography Catheter Dimension Broad Range Exemplary Range Catheter Body Length 50 cm-300 cm 90 cm-130 cm Catheter OD 1 mm-10 mm 1 mm-3 mm Catheter Lumen ID 0.5 mm-9.5 mm 0.5 mm-2.5 mm Distal Port Length .sub.1 1.4 mm-15 mm.sup. 3 mm-6 mm Distal Port Width 0.3 mm-1.5 mm 0.4 mm-1.2 mm Wire Length .sub.2 3 cm-30 cm 5 cm-20 cm Wire Diameter d.sub.W 0.2 mm-1 mm 0.3 mm-0.6 mm

[0039] The distal end of the catheter 10 differs from those of conventional angiography catheters in at least three particular respects. First, the catheter has a fixed guidewire allowing the catheter to be advanced through the vasculature without using a separate, moveable guidewire as discussed in the Background section above. Elimination of the moveable guidewire is advantageous as it both decreases the stiffness of the catheter as it is advanced and reduces the risk of generating air emboli associated with guidewire retraction. Elimination of the moveable guidewire also reduces the risk of clot formation since availability of the open lumen allows continuous infusion of heparinized saline. Conventional angiography catheters with moveable guidewires allow only intermittent anterograde infusion. Second, location of a bevel immediately proximal to the fixed guidewire attachment location provides a very smooth, tapered profile that facilitates catheter advancement through tortuous regions of the vasculature. In particular, the shelf present at the junction of a moveable guidewire and a catheter tip in a conventional angiography system is eliminated. Third, the beveled distal tip allows formation of an elliptical port which is larger than a circular port formed orthogonally across the tip of the catheter as with most conventional catheters. The larger area of the elliptical port lowers flow resistance to the delivery of contrast media and other substances delivered through the catheter lumen in addition having a larger cross sectional area increases the aspiration power compared to a conventional cylindrical catheter.

[0040] By elliptical, it is meant that the port will have a larger axial dimension (length) than lateral dimension (width). When measured across the open port area, the lateral dimension may be as large as the inner diameter of the catheter body lumen measured at the location of the port, typically being at least 50% of the width, usually being at least 75% of the width, and typically being at least 90% of the width. The axial dimension (length) will be typically be at least 1.5 fold greater that the maximum lateral dimension (width), usually being at least 3 fold grater, often being at least 5 fold greater.

[0041] The catheter body 12 may be constructed by polymer extrusion or three-dimensional printing in accordance with well known medical catheter fabrication techniques. The catheter body may optionally be reinforced to enhance torqueability, e.g. with braids, helical wires, coils, or other well-known reinforcement techniques. The fixed wire may also be constructed by known techniques for fabricating fixed and moveable guidewire, typically having a coiled exterior shell and a malleable internal core. The wire will be attached to the distal tip of the catheter body, preferably at the distal-most location on the distal tip, i.e. at the distal end of the elliptical port 16. Usually, a proximal portion of the wire 20 will be fixed to the catheter body by embedding a length in a wall of the body. The embedded length will usually be from 1 to 25 mm, usually being from 3 mm to 10 mm. Embedding may conveniently be achieved by wrapping a distal portion of the catheter wall around the proximal end or shank of the guidewire and then heat or ultrasonically welding the resulting junction. Alternatively or additionally adhesives, staples, rivets, and other external fasteners could be employed.

[0042] Referring now to FIG. 3, a second exemplary catheter 24 comprises having a catheter body 26 with a beveled distal tip 28 with fixed guide 34 extending distally from an elliptical port 30 at the distal end of a central lumen 32. The catheter 24 is similar in most or all respects to catheter 10 except for the shape of the elliptical port 30. While elliptical port 16 has a generally flat or straight planar opening (i.e. the periphery of elliptical port 16 lies in a flat plane), elliptical port 30 is non-planar with a concave or scalloped periphery. Such a concave or scalloped periphery increases the open port area available for release and/or aspiration of contrast media or other substances and can thus decrease flow resistance and/or increase flow rate through the port.

[0043] Other advantages of the more concave bevel include (1) a concave bevel will reduce trauma as the catheter passes by the takeoff of other vessels, (2) a concave bevel, rather than a straight bevel profile, will increase the cross sectional diameter of the catheter even further, increasing the aspiration power even further, (3) the proximal end of the catheter has a torpedo like design proximal to the female luer connector (FIG. 4), with low profile wings encircling the catheter, and (4) the design will facilitate torqueing of the entire catheter-wire device.

[0044] FIG. 4 illustrates an exemplary proximal hub 42 on the proximal end on the catheter body 12 or 26. The proximal hub will typically have a luer or other conventional fitting 40 at its proximal terminus for connection to a source of contrast media or other substance to be delivered as described further below. Conveniently, the hub may have fins 44 (referred to as a torpedo structure) or other gripping features to facilitate manipulation and torqueing by the physician to steer the catheter 10 or 24 as it is advanced through the vasculature.

[0045] FIG. 5 illustrates connection of the hub 42 of catheter 10 or 24 to a fitting 50 used to introduce heparinized saline and contrast media. The fitting 50 has a side branch 52 connected to a three-way valve 54. Heparinized saline can be fed into the catheter by a saline line 56 connected to one port of the three-way valve. Contrast media can be injected through a septum 58 connected to the other port of the three-way valve using a syringe.

[0046] Referring now to FIG. 6, the beveled tips 14 and 28 of catheters 10 and 24 of the present invention will facilitate atraumatic advancement of the catheter through the ostium of other vessels. The olive, beveled catheter tip facilitates placement of the catheter on straight segments. This differs from current technologies where an angled catheter tip faces against the arterial wall directly as shown in FIG. 1. The catheters of the present invention with an embedded wire at the beveled tip can eliminate the need to remove the wire every time the catheter is advanced, thus preventing the introduction of air bubbles and other risks of repeated catheter removals and insertions. The malleable distal wire that can be reformed into any desired shape or angle, according to the particular architecture of the vessel to be catheterized. Not having to remove the wire every single time prior to contrast injection expedites the procedure.

[0047] The diagnostic catheters of the present invention allow the injection of contrast material to opacify intravascular structures and to then allow continuous heparinized saline infusion to prevent clot formation, or to aspirating either by hand with a syringe or an aspiration pump, by a simple rotation of the three-way valve 54 since there is no need to remove the wire (this is not possible with conventional angiography catheters where the presence of a movable wire in the central lumen inhibits contrast injection). Combining the catheter body and the wire in one device improves the torqueing ability of the assembly as a whole. In conventional angiography catheters, only the wire is torqued by hand or by using a collet that grasps the wire. Using either approach, rotating an MP catheter is difficult due to the tip angle. In cases of extreme tortuosity is possible to advance a second wire through the main lumen of the catheter as a buddy wire while the embedded wire stabilizes the apparatus.

[0048] As shown in FIGS. 6, and 6A, an access sheath 62 is placed in the femoral artery in a patient's groin. The catheter 10 or 24 is advanced through the iliac artery IA and upward through the descending aorta A until reaching the aortic arch AA. The fixed wire 20 or 34 can be pre-shaped to allow the distal tip 14 or 28 to be torqued to steer the wire into the innominate artery and then into the target left common carotid artery LCA. FIGS. 6 and 6A show a bovine variant of the aortic anatomy which presents particular placement challenges. Once the port 16 or 30 is advanced past the os of the target left common carotid artery LCA, the contrast media can be delivered and angiography performed.

[0049] FIG. 6B illustrates placement of the catheter 10 or 24 through a septum 64 of a hub 66 of the access sheath 62. The beveled tip with fixed guide wire of the present invention facilitates the introduction of the distal tip of the catheter through the access sheath without the need for an introducer.

[0050] Referring now to FIGS. 7 and 7A-7D, a third exemplary catheter 70 comprises a catheter body 72 with a beveled distal tip 74 with fixed guide wire 80 extending distally from an elliptical port 76 at the distal end of a central lumen 78. The proximal portion (not shown) of catheter 70 may be similar or identical in at least most respects to the proximal portions catheters 10 and 24. The distal portion of catheter 70 will, in contrast, differ in significant respects. The fixed wire 80 will has a shank region 82 with an arcuate or semi-circular cross-section, as best seen in FIG. 7B, The semi-circular shank is embedded in a C-shaped distal region of the catheter body 72, as also best seen in FIG. 7B. The combined cross-sections of the shank 82 and the C-shaped region 84 form a trough which open the distal end of the elliptical port 76 to further reduce flow resistance when compared to that of the ports of catheters 10 and 24 described previously. The fixed wire 80 extends distally from the embedded shank region 82 and undergoes a gradual transition through a transition region 68 (FIG. 7C) until it reaches a generally circular profile 88 (FIG. 7D) over its distal portion.

[0051] While preferred embodiments of the present invention have been shown and described herein; it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.