BACKGROUND OF THE INVENTION

The present invention relates to a multifunction catheter for performing intravascular procedures, which catheter permits a number of operations useful during percutaneous transluminal coronary angioplasty (PTCA) in a single device, including guidewire exchange, addition of a second guidewire, exchange of a second catheter, deconvolute a tortuous route and delivery of a medicament to a stenosed site.

In typical PTCA procedures, a guiding catheter having a distal tip is percutaneously introduced into the cardiovascular system of a patient and advanced therein until the distal tip thereof is disposed within the aorta adjacent the ostium of the desired coronary artery. The guiding catheter is twisted or torqued from its proximal end, which extends outside of the patient, to turn the distal tip of the guiding catheter so that it can be guided into the coronary ostium and seated therein. A dilatation catheter having a dilatation balloon on the distal end thereof and a guidewire slidably disposed within an inner lumen of the dilatation catheter are introduced into and advanced through the proximal end of the guiding catheter to the distal tip of the guiding catheter seated within the coronary ostium. The distal tip of the guidewire is usually manually shaped (curved) by the surgeon prior to introduction into the guiding catheter along with the dilatation catheter.

The shaped distal tip of the guidewire is first advanced out from the distal tip of the guiding catheter into the patient's coronary artery. A torque is applied to the proximal end of the guidewire, which extends out of the proximal end of the guiding catheter as it is advanced within the coronary anatomy, to guide the curved or otherwise shaped distal end of the guidewire into a branch artery targeted for dilatation. The advancement of the guidewire within the target artery continues until it crosses the lesion to be dilated.

The dilatation catheter is then advanced out from the distal tip of the guiding catheter, over the previously advanced guidewire, until the balloon on the distal extremity of the dilatation catheter is properly positioned across the lesion to be dilated. Once properly positioned across the lesion, the flexible, relatively inelastic dilatation balloon on the catheter is inflated to a predetermined size with radiopaque liquid at relatively high pressures (e.g. generally 4-12 atmospheres) to dilate the stenosed region of the diseased artery. One or more inflations of the balloon may be required to complete the dilatation of the stenosis.

After the last dilatation, the balloon is deflated so that the dilatation catheter can be removed from the dilated stenosis and so that blood flow can resume through the dilated artery.

A problem arises during surgical interventions when the operating surgeon needs to change the guiding catheter or guidewire, which entails withdrawal of the part, and subsequent loss of progress made through the vasculature to reach the stenosed region. Further, a surgeon may encounter a region that is so convoluted that the passage of a balloon or stent catheter is restricted. There has been no single device that can offer the possibility to exchange in situ elements which at the same time can assist with deconvoluting a vacuous structure. The in-place guidewire may need to be replaced with another guidewire having a different structure, e.g. from a floppy-type design with a separate shaping ribbon to an intermediate or standard with a core wire which extends to the distal tip of the guidewire, or it may need to be withdrawn in order to reshape the distal tip and then be reinserted. A second catheter such as a guiding catheter may need to be replaced with one having a narrower gauge or with a different structure.

What has been needed and heretofore unavailable is an intraluminal multifunction catheter, preferably in a kit, which provides for the easy and rapid exchange of a second catheter and/or the guidewire used to guide the catheter through a body lumen, and which can assist with deconvoluting the tortuous path of a vessel. The present invention satisfies these and other needs.

FIGURE LEGENDS

FIG. 1 A three dimensional view of the multi-functional intraluminal catheter of the invention.

FIG. 2 A transverse cross-sectional view taken along line 2-2 in FIG. 1.

FIG. 3 A longitudinal cross-sectional view taken along line 2-2 in FIG. 1 showing the side port.

FIG. 4 A transverse cross-sectional view taken along line 4-4 in FIG. 1. FIG. 5 An enlarged view of the proximal end of the catheter shown by the ellipse in FIG. 1.

FIG. 6 An enlarged view of the distal end of the catheter shown by the ellipse in FIG. 1.

FIG. 7 A three dimensional view of extension piece of the invention.

FIG. 8. An enlarged view of the distal end of the catheter shown by the ellipse in FIG. 7.

FIG. 9 A three dimensional view of the multi-functional intraluminal catheter of the invention stiffened by a proximal hollow rope tube. FIG. 10A is a transverse (A-A) cross-section through the S-region of a catheter as shown in FIG. 9, whereby the cables of the hollow rope tube have a circular profile, and the hollow rope tube is devoid of coating or jacket.

FIG. 1OB is a transverse (B-B) cross-section through the T-region of a catheter as shown in FIG. 9, whereby the cables of the hollow rope tube have a part-circular profile, and the hollow rope tube is devoid of coating or jacket.

FIG. 1OC is a transverse (C-C) cross-section through the F-region of a catheter as shown in FIG. 9, whereby the cables of the hollow rope tube have a semi-circular profile, the hollow rope tube is devoid of coating or jacket. FIG. 11A is a transverse (A-A) cross-section through the S-region of a catheter as shown in FIG. 9, whereby the cables of the hollow rope tube have a circular profile, and the hollow rope tube has a coating of constant thickness.

FIG. 11 B is a transverse (B-B) cross-section through the T-region of a catheter as shown in FIG. 9, whereby the cables of the hollow rope tube have a part-circular profile, and the hollow rope tube has a coating of constant thickness.

FIG. 11C is a transverse (C-C) cross-section through the F-region of a catheter as shown in FIG. 9, whereby the cables of the hollow rope tube have a semi-circular profile, and the hollow rope tube has a coating of constant thickness.

FIG. 12A is a transverse (A-A) cross-section through the S-region of a catheter as shown in FIG. 9, whereby the cables of the hollow rope tube have a circular profile, and the hollow rope tube has a coating that is thickest in the S-region.

FIG. 12B is a transverse (B-B) cross-section through the T-region of a catheter as shown in FIG. 9, whereby the cables of the hollow rope tube have a circular profile, and the hollow rope tube has a coating that is intermediate thickness in the T-region. FIG. 12C is a transverse (C-C) cross-section through the F-region of a catheter as shown in FIG. 9, whereby the cables of the hollow rope tube have a circular profile, and the hollow rope tube has a coating that is thinnest in the F-region.

FIG. 13 is an illustration of the apparatus used to prepare a hollow rope tube of the present invention. FIGs. 14 to 22 sequence of figures illustrating the procedure for replacing a second catheter.

FIGs. 23 to 27 sequence of figures illustrating the procedure for provided a second guidewire.

FIG. 28 A view of the stiffening mandrel of the invention. FIGs. 29 and 30 sequence of figures illustrating the procedure for deconvoluting the tortuous path of a vessel. SUMMARY OF THE INVENTION

This invention is directed to a multifunction intraluminal catheter system which provides for the exchange of the guidewire, for introducing a second guidewire, for exchange of a second (e.g. guiding) catheter, for deconvoluting a tortuous path in a patient's vasculature, for delivery of fluid medicament and to the use of this system, particularly within the coronary arteries of a human patient during an angioplasty procedure.

The multifunction intraluminal catheter of the invention generally comprises an elongated catheter shaft with a single guidewire receiving inner lumen extending therein to a guidewire port in the terminus of distal end of the catheter. A distal side port is provided in the catheter shaft spaced longitudinally no more than 16 mm from the distal end of the shaft which is in fluid communication with the guidewire receiving inner lumen. The elongated catheter shaft is preferably adapted to guide the proximal end of a guidewire out from the side port as the proximal end of the guidewire is advanced through the inner lumen of the multi-functional catheter from the distal guidewire port. The proximal port may be adapted with a connector 40 for dismountable attachment to an extension piece. The catheter is preferably provided as a kit together with the extension piece.

In one preferred embodiment, the side port is slightly angled with respect to the longitudinal axis of the catheter, e.g. about 5 to about 40 degrees, preferably about 5 to about 30 degrees, so that the proximal end of the guidewire will advance from the side port without substantial kinking.

The catheter shaft has a narrow profile, no more than 2.7 F and the distal end of the catheter shaft is preferably shaped, e.g. tapered, and dimensioned so as to be easily advanced through the vasculature of a subject, over a placed guidewire. It is also narrow that it can be inserted in the lumen of a second catheter (e.g. a guiding catheter) in an over-the-wire mode or in rapid-exchange mode when the guidewire extends from a proximal guidewire port of the second catheter.

The multifunction catheter is adapted to be advanced over a guidewire, which is disposed within the vasculature of a patient. The proximal end of the in-place guidewire is fed through the distal guidewire port of the multifunction catheter and out through the side port, and the multifunction catheter is advanced along the guidewire, through the vasculature. A radiopaque marker adjacent to the side port allows the surgeon to position the side port distal to the stenosed region, for example, by a distance of 5 mm. The radiopaque marker may be positioned adjacent to the side port 38, e.g. 0 mm, 1 mm, 2 mm, or 3 mm distal or proximal to the side port 38, or a distance in the range between any two of the aforementioned values. The in-place guidewire is then withdrawn proximally from the patient's arterial system by pulling on the proximal end of the guidewire which extends out from the patient, while the position of the multifunction catheter is maintained. A replacement long guidewire, preferably pre-loaded in the multifunction catheter, may then be advanced through the inner lumen of the multifunction catheter, until the guidewire extends from the distal guidewire port in the multifunction catheter. The multifunction catheter can then be withdrawn.

The profile of the multifunction catheter is narrow that it can be advanced through the lumen of a second, in-place catheter (e.g. a guiding catheter) in an over-the-wire mode or in rapid-exchange mode when the guidewire extends from a proximal guidewire port or side port of the second catheter. The proximal end of the in-place guidewire is fed through the distal guidewire port of the multifunction catheter and out through the side port, and the multifunction catheter is advanced along the guidewire and through the second catheter, until the distal tip is well within the lumen of the second catheter, or more preferably, until the distal tip exits the second catheter at a distal port. A radiopaque marker adjacent to the side port allows the surgeon to position the side port distal to the stenosed region, for example, by a distance of 5 mm. The in-place guidewire is then withdrawn proximally from the patient's arterial system by pulling on the proximal end of the guidewire which extends out of the patient, while the position of the multifunction catheter is maintained. A replacement guidewire, preferably pre-loaded in the multifunction catheter, may then be advanced through the inner lumen of the multifunction catheter, until the guidewire extends from the distal guidewire port in the multifunction catheter. The multifunction catheter can then be withdrawn through the lumen of the second catheter.

The procedure for adding a second guidewire to an already in place guidewire follows the above steps, with the exception that after the multifunction catheter is placed using the radiopaque marker, the in-place guidewire is then withdrawn proximally only by an amount that permits disengagement from the multifunction catheter. The in-place guidewire is then advanced again to its previous location. The position of the multifunction catheter is either maintained, or the tip can be directed to another location, for example the along another an arterial branch. A second long guidewire, preferably pre-loaded in the multifunction catheter, may then be advanced through the inner lumen of the multifunction catheter, until the guidewire extends from the distal guidewire port in the multifunction catheter. The multifunction catheter is then withdrawn, so leaving two guidewires in place.

Distal tip of the multifunction catheter, introduced through a lumen in a second catheter, may be allowed to protrude through the distal port of the second catheter. By pushing the smaller flexible multifunction catheter further forward in advance of the second, larger catheter, the tortuous path of a vessel that prevents the second catheter from progressing to the stenosed region, can be deconvoluted. Where the multifunction catheter has adapted to the tortuous shape of a vessel, the catheter and hence vessel may be deconvolutedby advancing a stiffening mandrel through the lumen of the multifunction catheter. Once deconvoluted, the second catheter can be advanced further still. When the stenosed region has been reached, the original guidewire is replaced if necessary as described above, multifunction catheter removed, and the second catheter pushed forward to the stenosed region.

As mentioned elsewhere, the profile of the multifunction catheter is narrow that it can be advanced through the lumen of a second, in place catheter (e.g. a guiding catheter) in an over-the-wire mode or in rapid-exchange mode when the guidewire extends from a proximal guidewire port or side port of the second catheter. The proximal end of the in- place guidewire is fed through the distal guidewire port of the multifunction catheter and out through the side port, and the multifunction catheter is advanced along the guidewire and through the second catheter, until the distal tip is well within the lumen of the second catheter, or more preferably, until the distal tip exits the second catheter at a distal port. The second catheter can be withdrawn over the shaft of the multifunction catheter. Prior to withdrawal, an extension piece is attached to the proximal end of the multifunction catheter using a demountable connection, that creates an essentially single continuous elongated member having a maximum diameter of 2.7F over which the second catheter is withdrawn. The extension piece provides a handle to maintain the position of the distal end of the multifunction catheter in situ while the second catheter is pulled over the proximal end of the multifunction catheter. The proximal end of the extension piece is fed through the lumen of a replacement second catheter and, the replacement second catheter is advanced along the vasculature using the body of the multifunction catheter. The multifunction catheter can be used to deliver fluid medication, introduced through the proximal port, conducted along the single lumen, to the distal end of the catheter. Fluid medication, exiting the multifunction catheter at the side port or the distal port, is delivered to the stenosed site.

One embodiment of the invention is a kit comprising: A) an intraluminal multifunction catheter (100) comprising an elongated shaft (30) having a proximal end (20), a distal end (10) and a single inner lumen (32) extending therein in fluid connection with :

- a distal guidewire port (34) located at the terminus (33) of the distal end (10) of the shaft (30), - a distal side port (38) located at a longitudinal distance, d, of between 8 mm and

26 mm in the proximal direction from the distal terminal port (34),

- a proximal guidewire port (36) located at the terminus (35) of the proximal end (20) of the shaft (30), whereby the proximal port (36) is disposed with a connector (40), for dismountable attachment to an extension piece (200), and

B) an extension piece (200) comprising an elongated shaft (60) having a proximal end (55), a distal end (50) that terminates in a reciprocating connector (68) to the catheter shaft connector (40), whereby the elongated shaft (30) and extension shaft (60) in attachment form a continuous elongated member for passage through a lumen of a second catheter. The connector (40) may also be for dismountable attachment to a handle (70). The distance, d, may alternatively be between 8 and 12 mm, or between 1 1 and 26 mm.

Another embodiment of the invention is a kit as described above, wherein the connector (40) of the catheter shaft (30) is further adapted for attachment to a fluid delivery fitting.

Another embodiment of the invention is a kit as described above, wherein the connector (40) of the catheter shaft (30) and reciprocating connector (68) comprises a screw thread arrangement.

Another embodiment of the invention is a kit as described above, wherein the maximum diameter of the catheter shaft (30) and/or extension shaft (60) is no more than 3.0 F or 2.7 F. Another embodiment of the invention is a kit as described above, wherein the maximum diameters of the catheter shaft (30) and the extension shaft (60) are the same in the region adjoining the connectors (40, 68).

Another embodiment of the invention is a kit as described above, further comprising a stiffening mandrel (140) having a proximal end (146) and distal end (144) configured for insertion into the single inner lumen (32).

Another embodiment of the invention is a kit as described above, wherein the stiffening mandrel (140) is disposed with a limit stop handle (143) at the proximal end (146) configured to prevent the distal end (144) of the inserted mandrel (140) from advancing past the region proximal to the side port (38) of the multifunction catheter (100).

Another embodiment of the invention is a kit as described above, wherein the single inner lumen (32) is fluid impermeable.

Another embodiment of the invention is a kit as described above, wherein the elongated (30) shaft is formed from a single material.

Another embodiment of the invention is a kit as described above, wherein the elongated shaft is at least partly stiffened in the section spanning the proximal end (20) and the side port (38).

Another embodiment of the invention is a kit as described above, wherein the elongated shaft is least partly stiffened using hypotubing.

Another embodiment of the invention is a kit as described above, wherein the extension shaft (60) is disposed with a dismountable handle (70) at the proximal end (55).

Another embodiment of the invention is a kit as described above, wherein the diameter of the catheter inner lumen (32) is between 0.4 and 0.6 mm.

The advantages of the invention described above and others will become more apparent from the following detailed description thereof when taken in conjunction with the accompanying exemplary drawings. DETAILED DESCRIPTION OF THE INVENTION

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art. All publications referenced herein are incorporated by reference thereto. All United States patents and patent applications referenced herein are incorporated by reference herein in their entirety including the drawings.

The articles "a" and "an" are used herein to refer to one or to more than one, i.e. to at least one of the grammatical object of the article. Throughout this application, the term "about" is used to indicate that a value includes the standard deviation of error for the device or method being employed to determine the value.

The recitation of numerical ranges by endpoints includes all integer numbers and, where appropriate, fractions subsumed within that range (e.g. 1 to 5 can include 1 , 2, 3, 4 when referring to, for example, a number of elements, and can also include 1.5, 2, 2.75 and 3.80, when referring to, for example, measurements). The recitation of end points also includes the end point values themselves (e.g. from 1.0 to 5.0 includes both 1.0 and 5.0).

Reference is made in the description below to the drawings which exemplify particular embodiments of the invention; they are not at all intended to be limiting. The skilled person may adapt the device and method and substitute components and features according to the common practices of the person skilled in the art.

The terms "distal" and "proximal" are used through the specification, and are terms generally understood in the field to mean towards (proximal) or away (distal) from the surgeon side of the apparatus. Thus, "proximal" or "proximal end" means towards the surgeon side and, therefore, away from the patient side. Conversely, "distal" or "distal end" means towards the patient side and, therefore, away from the surgeon side.

Reference is made to FIGS. 1 to 6 which depict a multifunction catheter 100 embodying features of the invention. The multifunction catheter 100 includes a relatively long tubular catheter shaft 30, having a proximal end 20 and distal end 10 and a single inner lumen 32 extending therein. The lumen 32 is in fluid connection with a distal port 34 located at the terminus 33 of the distal end of the catheter shaft 30 and also with a proximal port 36 located at the terminus 35 of the proximal end of the catheter shaft 30. The proximal port 36 may be adapted with a connector 40 for dismountable attachment to an extension piece or to a fluid delivery fitting such as a Luer connector. Alternatively, the proximal port 36 may be adapted with a Luer connector 43. The tubular catheter shaft 30 is disposed with a side port 38 located at a longitudinal distance, d, from the distal terminal port 34 in the proximal 20 direction.

As shown in FIG. 2 and 3, depicting transverse cross sections of the catheter shaft, the outer wall of the catheter shaft 30 is complete and intact along the length, to provide a fluid impermeable passage that facilitates transport of fluid along the inner lumen 32 to the catheter tip 37. The catheter shaft 30 may be formed from a continuous length of tubing of a single material. The single material may extend from the terminus 33 of the distal end to the terminus 35 or connector 40, 43 at the proximal end. Examples of suitable materials include high and/or low density polyethylene, polyamides, poly(ethylene terephthalate) (PET) or polyesters and copolymers thereof. To provide pushability, a length of catheter shaft between the terminus 35 or connector 40, 43 of the proximal end 20 and the side port 38 may be relatively stiff in comparison to the length distal 10 to the side port 38. This may be achieved by disposing hypotubing within the lumen 32 or wall of the catheter shaft 30 at least partly in the section proximal to the side port 38. Alternatively, the catheter shaft 30 may be formed from more than one material, for example, a flexible tubing from the distal terminus 33 until the side port 38 (i.e. the tip 37 of the catheter), that is bonded or connected to a more rigid tubing extending from the side port 38 to the proximal end 20. The hypotubing, where employed, may be formed of stainless steel or a superelastic NiTi alloy. The stiffer sections of the shaft, when present, may be made from high and/or low density polyethylene, polyamides, poly(ethylene terephthalate) (PET) or polyesters and copolymers thereof, or from fluid-impermeable hypotubing. The more flexible sections of the shaft (e.g. the tip from the side port 38 to the distal terminus 33) may be made from a polymeric tubing such as high and/or low density polyethylene, polyamides, poly(ethylene terephthalate) (PET) or polyesters and copolymers thereof. The overall length of the multifunction catheter 100 is typically about 100 to about 190 cm.

According to one aspect of the invention, at least part of the catheter shaft between the terminus 35 or connector 40, 43 of the proximal end 20 and the side port 38 is stiffened in comparison to the length distal 10 to the side port 38 by way of a hollow rope tube 72 formed from a plurality of longitudinal wire cables cylindrically stranded to form the hollow rope tube 72. The hollow rope 72 may have a uniform flexibility from its proximal to distal which may be achieved with a uniform duct diameter or wall thickness. Alternatively, the distal end of the hollow rope may be more flexible than the proximal end, and a region of transitional flexibility may be used to connect the differentially flexible ends. When the hollow rope tube 72 is present, the catheter shaft 30 thus comprises the hollow rope tube 72 connected at its distal end to a polymeric tubing 74 (FIG.9) which contains the side port 38 and distal terminus 33.

The hollow rope tube 72 is made by cylindrically stranding a group of stainless steel wires along a predetermined circle line to provide a hollow rope tube 72 of the invention. An inner surface 25 of the hollow rope tube 72 forms a plurality of concave structures represented by the stainless steel wires 41 , 41' that are circular in cross-section. Such tubing is known in the art, for example, the Actone cable tube as manufactured by Asahi Intecc, and described, for instance, in US 2004/0249277. An outer surface 27 of the hollow rope tube 72 may be rendered partially smooth in regions of increased flexibility giving rise to wires 41 , 41' that are part or semi-circular, while the inner surface forms the inner lumen 32 in which the convex-concave structure resides. The hollow rope tube 72 is typically cylindrical. The hollow rope tube 72 has an inherent medium-impermeable property, however, it may rendered medium-impermeable at higher pressures, for instance up to 30 bar by a medium-impermeable coating or jacket.

The hollow rope tube 72 may have 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23 or 24 metallic wires 41 , 41 ', or a number in the range between any two of the aforementioned values, preferably between 2 and 24.

The hollow rope tube 72 may be manufactured according to a scheme as shown in FIG. 13. Namely, a wire rope R is provided by stranding the metallic wires 41 , 41' around an elongated core (not shown). One end of the wire rope R is secured to a rotational chuck 61 of a twisting device 71. The other end of the wire rope R is secured to a slidable chuck 63 from which a weight 66 is attached applying a longitudinal force. The wire rope R is twisted under the tensile force applied by the weight 67. A current generating device 68 provides electric currents to the chucks 61 and 63 through an electric wire 64 so that the wire rope R is heated by its electric resistance to remove the residual stress appeared on the wire rope R during the twisting process. Once the rope has formed, the outer surface of the hollow rope tube 72 may be smoothly ground to provide the requisite flexibility as necessary so that the metallic wires 41 , 41' have a semi- or part-circular cross-section in the flexible regions. The elongated core is withdrawn from the wire rope R to provide a hollow tube structure that is the hollow rope tube 72. The hollow rope tube 72 formed from the plurality of wire cables may be provided with a jacket or coating 51, 52, 54, 56 (FIGs. 11A to 11C; FIGs. 12A to 12C) made from a substance typically used to form lumens in corresponding catheters of the art. For example, the jacket or coating may comprise materials such as high and/or low density polyethylene, polyamides, poly(ethylene terephthalate) (PET) or polyesters and copolymers thereof, teflon or any such material that comprises a hydrophilic character. The coating or jacket improves the medium-impermeable property of the hollow rope tube 72. In the case of a coating, it can be applied by spraying, dipping a liquid form of the polymer over the surface of the hollow rope tube 72, or other methods know in the art. In the case of a jacket, it may be slid in or over the hollow rope tube 72; advantageously, the longitudinal disposition of the cables facilitates sliding of the jacket. It is within the scope of the invention, that the coating is applied on the outside and/or the inside surface(s) of the hollow rope tube 72. The interior surface 25 of the hollow rope tube 72 may be coated with or comprise a tubing made of high and/or low density polyethylene, polyamides, poly(ethylene terephthalate) (PET) or polyesters and copolymers thereof or Teflon.

As mentioned elsewhere, the hollow rope tube 72 may have a region of transitional flexibility between its proximal 20 and distal ends 10. The region provides a gradually changing flexibility from a stiffer proximal end to a less stiff (more flexible) distal end, thereby imparting differential flexibility on the multifunction catheter 100.

The outer diameter of the hollow rope tube 72 may gradually decrease in a direction from the proximal end 20 to the distal end 10 in the region of transitional flexibility, whereby the maximum diameter of the catheter shaft 30 is not exceeded. Proximal 20 to the region of transitional flexibility, the outer diameter of the hollow rope tube 72 may be essentially constant and essentially equal to the largest diameter present in the region of transitional flexibility. Distal 10 to the region of transitional flexibility, the outer diameter of the hollow rope tube 72 may be essentially constant and essentially equal to the smallest diameter present in the region of transitional flexibility. The inner diameter of the hollow rope tube 72 remains constant along the length of the hollow rope tube 72.

The distal end 10 of the hollow rope tube 72 may have a section in the lengthwise direction known herein as a flexible (F) region, depicted in FIG. 9. The proximal end 20 of the hollow rope tube 72 may have a section in the lengthwise direction that belongs to the stiff (S) region as known herein. The hollow rope tube 72 in the F-region exhibits greater flexibility compared with the hollow rope tube 72 in the S-region. A lengthwise portion, the transition (T) region, between the F-region and S-region may serve as a region of transitional flexibility between the F-region and S-region. The S-region provides the requisite pushability to advance the multifunction catheter 100 from the proximal end 20 without kinking the catheter, while the F-region being more flexible, can bend and flex around the tortuous route of a vasculature. The T-region effectively buffers the movements between the F-region and S-region.

The flexibility of the hollow rope tube 72 in the F-region may be increased compared with that in the S-region by a diametric reduction of the hollow rope tube 72. A lengthwise portion, the T-region, between the F-region and S-region diametrically increases progressively from distal 10 to the proximal 20 end to serve as a region of transitional flexibility between the F-region and S-region. As shown in FIGS. 10A, 10B and 10C the outer diameter of the hollow rope tube 72 is maximal in the S-region (FIG. 10A), minimal in the F-region (FIG. 10C) and is transitional in the T-region (FIG. 10B). It will be appreciated that the cross-sections in the T-region progressive increase in diameter from the distal to proximal end. The smaller outer diameter combined with a constant internal diameter provide a thinner wall in the F-region exhibiting increased flexibility compared with the thicker walled hollow rope tube 72 in the S-region. The outer diameter of the hollow rope tube 72 may be modified by chemical treating or deforming or grinding the outside surface, for instance the metallic wires 41 , 41 ' have a circular form in cross section with its outer surface not ground in the S-region (FIG. 10A), compared with in the F-region where the ground wires adopt a semi-circular profile (FIG. 10C).

According to an aspect of the invention, the hollow rope tube 72 may be provided with a polymeric coating or jacket. The purpose of the jacket may be to provide or enhance medium impermeability. Where the differently flexible regions are provided by diametric changes in the hollow rope tube 72, the thickness of the jacket or coating may be constant as shown in FIGs. 11 A, 11 B and 11 C, where the coating 51 thickness is the same in the

S-region (FIG. 11A), T-region (FIG. 11 B) and F-region (FIG. 11C). In such cases, the jacket or coating thickness does not contribute to differential flexibility.

According to another aspect of the invention, the hollow rope tube 72 may be disposed with a polymeric coating or jacket which thickness varies according to the desired flexibility. The purpose of the jacket may be to add medium impermeability, but also to control flexibility. In such cases, the diameter of the hollow rope tube 72 formed by the cables may be constant, and differential flexibility is achieved by virtue of the coating or jacket only.

The thickness of the coating or jacket only may gradually decrease in a direction from the proximal end 20 to the distal end 10 in the region of transitional flexibility. Proximal 20 to the region of transitional flexibility, the thickness of the coating or jacket may be essentially constant and essentially equal to the largest thickness present in the region of transitional flexibility. Distal 10 to the region of transitional flexibility, the thickness of the coating or jacket may be essentially constant and essentially equal to the smallest thickness present in the region of transitional flexibility. The inner diameter of the hollow rope tube 72 remains constant along the length of the hollow rope tube 72; and outer diameter preferably remains constant, or may vary to further enhance differential flexibility.

Depicted in FIG. 12A to 12C is the instance where the hollow rope tube 72 has a constant diameter, the thickness of the coating 52 in the S-region (FIG. 12A) is greater compared with in the F-region (FIG. 12C) and the section is accordingly stiffen T-region exhibits a transition thickness at the section indicated (FIG. 12B). According to one aspect of the invention, differential flexibility may be enhanced by combining both diametric changes in hollow rope tube 72 with variable coating or jacket thicknesses.

The minimum thickness of the coating or jacket in the F-region, may be equal to or no more than 100%, 98 %, 96 %, 95 %, 90 %, 85 %, 80 %, 75 %, 70 % of the thickness of the coating or jacket in the S-region. The maximum thickness of the coating or jacket in the S-region may be equal to or no greater than 0.01 mm, 0.02 mm, 0.04 mm, 0.06 mm, 0.08 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, or a value in the range between any two of the aforementioned values, preferably between 0.01 mm and 0.2 mm.

Other ways to achieve a variation in flexibility includes differentially tempering the metal during formation of the rope, changing the weight applied during the stranding process, changing the diameter of the elongated cores used during stranding, changing the type of metal used during stranding.

The length of the F-region, may be 0%, 2%, 5%, 10 %, 20 %, 30 %, or 40 % of the length of the catheter or a value in the range between any two of the aforementioned values, preferably between 2 and 30%. The length of the T-region, may be 0%, 2%, 5 %, 10 %, 15%, or 20 %, of the length of the catheter or a value in the range between any two of the aforementioned values, preferably between 2 and 20%.

The length of the S-region, may be 40 %, 55 %, 60 %, 65 %, 70 %, 80%, 85%, 90%, 95% or 100% of the length of the catheter or a value in the range between any two of the aforementioned values, preferably between 70 and 95%.

The maximum total outer diameter of the hollow rope tube 72 in the F-region including any jacket or coating, may be equal to or no greater 100 %, 95 %, 90 %, 85 %, 80 %, 70 %, 60 % of the maximum diameter of the catheter shaft 30, or a value in the range between any two of the aforementioned values, preferably between 80 and 90%. The S-region may contain a portion of tubing having the maximum total outer diameter of the catheter shaft 30.

Advantageously, the hollow rope tube 72 facilitates the ease of passage of the guidewire, since the cables forming the inner lumen 32 run in a longitudinal direction. Advancement of a catheter of the art over a guidewire, can be difficult due to the guidewire frictionally engaging with the wall of a guidewire lumen. It is exacerbated in the case when the guidewire tip lodges in the gap of a bent hypotube spiral. Because the inner lumen is provided with a plurality of essentially longitudinal grooves in the present invention, the proximal end of the guidewire is actively guided in the longitudinal direction. Moreover, the cylindrical cables presents a plurality of convex surfaces which direct the guidewire away from the inner wall, compared with a concave surface of traditional catheters which contribute to passage of a guidewire into the inner wall, particularly at bends. In additional, the hollow rope tube 72 exhibits excellent torque transfer in both rotational (clockwise and anti-clockwise) directions. The flexibility of the hollow rope tube 72 gradually changes from the proximal end to the distal end, typically being more stiff at the proximal end so as to provide better pushability. The more flexible distal end facilitates advancement of the catheter tip through the tortuous route of the vasculature. The longitudinal disposition of the cables also facilitates covering with a jacket, which can be pulled over the hollow rope tube 72 with ease.

The when the multifunction catheter of the invention is stiffened by, for instance a hypotubing or hollow rope tube 72 as described above, the region from the distal end of the hollow rope tube 72 to the distal terminus 33 (e.g. the P-region as shown in FIG. 9) is formed from a polymeric tubing material. The polymeric tubing 74 is disposed with a lumen extending the length of the polymeric tubing; the lumen of the hollow rope tube 72 and the lumen of the polymeric tubing 74 are in fluid communication and their longitudinal axis are preferably aligned coaxially. In the case of the catheter comprising a hollow rope tube 72, the polymeric tubing 74 exhibits even greater flexibility than the hollow rope tube 72, or than the F-region of the hollow rope tube 72 where present. The polymeric tubing 74 may be made from high and/or low density polyethylene, polyamides, poly(ethylene terephthalate) (PET) or polyesters and copolymers thereof. The length of the region (e.g. the P-region as shown in FIG. 9), may be 1 %, 5%, 10 %, 20 %, 30 %, or 40 % of the length of the catheter or a value in the range between any two of the aforementioned values, preferably between 1 and 10%.

The polymeric tubing 74 may be attached to the hollow rope tube 72 or hypotubing using any suitable attachment means in the art, for instance, by way of a frictional joint e.g. a portion of the proximal end 20 of the polymeric tubing 74 or hypotubing being disposed over a portion of the distal end of the hollow rope tube 72 or hypotubing respectively in an overlapping manner. Other means include the use of adhesive, bonding or an inline adaptor (e.g. portion of bridging tubing) that mates one end of the hollow rope tube 72 or hypotubing with one end of the polymeric tubing 74. Other means include the use of heat bonding.

The maximum outer diameter of the catheter shaft 30, particularly in the region that will pass through the body may be equal to or no more than 1.2F, 1.5F, 1.6F, 1.7F, 1.8F, 1.9F, 2.0 F, 2.1 F, 2.2 F, 2.3 F, 2.4 F, 2.5 F, 2.6 F, 2.7 F, 3.0 F preferably no more than 3.0 F, more preferably no more than 2.7, even more preferably no more than 2.4 F. (1 F being equal to 0.33 mm diameter), or a value in the range between any two of the aforementioned values, preferably between 1.6 F and 2.7 F, or between 1.2 F and 3.0 F.

The diameter of the inner lumen 32 is sufficiently large to accommodate and permit slidable movement of a guidewire therein, and may depend on the gauge and length guidewire employed. According to one aspect of the invention, the diameter of the inner lumen 32 is equal to or no more than 10 %, 20 %, 30 %, 40 %, 50 %, 60 %, 70 %, 80 %,

90 % or 100 % larger than the external diameter of the guidewire, or a value in the range between any two of the aforementioned values, preferably between 10 % and 30%, or between 10 % and 40 %. According to one aspect of the invention the diameter of the inner lumen 32 is equal to or no more than 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm or 0.8, or a value in the range between any two of the aforementioned values, preferably between 0.3 and 0.6 mm.

The area disposed with the ellipse 5 in FIG. 1 is depicted in an enlarged view in FIG. 5, which shows the proximal port 36 disposed with a connector 40 for dismountable attachment to an extension piece. The connector 40 is configured to maintain a mechanical coupling with the extension piece that is resistive to pulling and pushing forces on the catheter and/or extension piece. The connector 40 is also preferably suited for attachment to a handle 70 for grasping the proximal end of the multifunction catheter 100. In one embodiment of the invention, the handle 70 is directly attached to the proximal end i.e. without the connector 40. The connector 40 is also preferably suited for coupling the proximal port to a fluid delivery fitting such as a Luer connector, that in turn can be coupled to a syringe or tubing. In one embodiment of the invention, the Luer connector 43 is directly attached to the proximal end i.e. without the connector 40 as shown, for instance, in FIG. 9. The fitting should provide a water-tight connection to the proximal port that can withstand pressure necessary for fluid medication delivery along the catheter lumen 32. An exemplary connector 40 configured to maintain a mechanical coupling with the extension piece shown in FIG. 5 comprises a screw thread that extends from the proximal port 36, outside surface of the catheter shaft 30 in a distal 10 direction. The thread has a profile narrower than the diameter of the catheter shaft 30 which can engage with a thread disposed in the lumen 62 of the extension piece 200 (e.g. FIG. 8). The screw thread connector, where implemented, may in an alternative embodiment (not shown) progress along the lumen 32 of the catheter shaft 30, in a distal direction from the proximal port 36. In an alternative embodiment (not shown), the connector may be a hollow cylindrical collar, open at both ends and concentrically disposed at one end over the proximal end 20 of the multifunction catheter and in a sealed attachment therewith. The other end of the cylindrical collar is disposed with one or more threaded regions. A (female) thread on the inside of the collar may be configured to engage with a reciprocating (male) thread on the extension piece 200 while a (male) thread on the outside of the collar may be configured to engage with a reciprocating (female) thread on the fluid delivery fitting. Either or both threads may be present. The connector 40 advantageously permits connection to an extension piece (e.g. FIG. 7 and 8) having a similar outer diameter to the catheter shaft 30, without substantially increasing the profile of the multifunction catheter 100 at the connection region. The connector allows an extended multifunction catheter 100 to pass through the lumen of a second catheter without substantial hindrance. The area disposed within the ellipse 6 in FIG. 1 is depicted in an enlarged view in FIG. 6, which shows the distal tip 37 disposed between the distal port 34 and side port 38. The distal tip 37 may be beveled or tapered as shown in FIG. 6 to facilitate the entry thereof into a bodily vessel and/or lumen of a second catheter. The longitudinal distance, d, between the distal port 34 and side port 38 is 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 1 1 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, preferably between 6 mm to 16 mm, 8 mm and 12 mm, 11 mm to 26 mm, 1 1 mm and 19 mm, 10 mm, or 15 mm which distance allows the skilled practitioner to disengage the multifunction catheter 100 from an in-place guidewire by advancing the distal terminal end 33 no further than essentially distance d past the distal end of the guidewire. Alternatively, it allows the surgeon to position the side port distal to the stenosed region (e.g. by 5 mm) and requiring a clearance of no more than essentially distance d distal to the side port. While a greater distance would provide increased support to the multifunction catheter mounted on the guidewire, it would also necessitate a corresponding length of clearance inside the vessel distal to the distal end of the guidewire, which, in a tortuous system would not be available. The distance d between 8 mm to 12 mm, preferably 10 mm optimizes support, while minimising the clearance. The catheter shaft 30 is also provided with a radiopaque marker 39, located at or adjacent to the side port 38. The catheter lumen 32 may be disposed with an internal guiding ridge positioned on the lumen wall opposite the side port 38, configured to direct a guidewire 94 entering through the distal port 34 out through the side port 38. Said ridge is also configured to allow a guidewire entering through the proximal port 34 to exit the catheter lumen 32 through the distal port 34.

In FIG. 7 is depicted an extension piece 200 that comprises an elongated extension shaft 60 having a proximal end 55 and distal end 50. It may optionally be disposed with a single inner lumen 62 extending within the shaft in fluid connection with at least a port 66 at the distal terminal end, and optionally a port at the proximal terminal end that can accommodate a guidewire. The lumen 62 may be shortened to just accommodate a connector 68 such as a screw thread. The proximal end 55 may optionally be disposed with a removable handle 70. The catheter shaft 30 and the extension shaft 60 in connection form a continuous elongated member for exchanging a second catheter. The extension shaft 60 may be formed from a continuous length of tubing of a single material that extends from the terminus of the distal end 50 to the terminus of the proximal end 55. Alternatively, it may be formed from more than one material for example, several tubular shafts bonded to form a single shaft. The extension shaft is flexible, and to provide pushability, may be stiffened to at least the same degree as the stiffest part of the catheter shaft 30. This may be achieved by disposing hypotubing within the wall or optional lumen 32 of the extension shaft 60. Alternatively, the shaft 60 may be formed from a material having the requisite bend resistance. The hypotubing, where employed, may be formed of stainless steel or a superelastic NiTi alloy and the wall of extension shaft from high and/or low density polyethylene, polyamids, poly(ethylene terephthalate) (pet) or polyesters and copolymers thereof. When hypotube is not employed, of the extension shaft may be made from high and/or low density polyethylene, polyamids, poly(ethylene terephthalate) (pet) or polyesters and copolymers thereof, stainless steel or a superelastic NiTi alloy and the wall of extension shaft from high and/or low density polyethylene, polyamids, poly(ethylene terephthalate) (pet) or polyesters and copolymers thereof. The overall length of the extension piece 200 is typically about 85 to about 150 cm.

The outer diameter of the extension shaft 60 is the same as or similar to that of the catheter shaft, or may differ by 1 %, 2 %, 3 %, 4 %, 5 %, 6 %, 7 %, 8 %, 9 %, 10 %, 15 %, 20 %, 25 %, 30 %, 35 %, 40 %. 45 %, 50 %, 60 % or 70 %, or a value in the range between any two of the aforementioned values i.e. it may have a larger or smaller diameter compared with the catheter shaft 30, preferably it is the same. According to one aspect of the invention the outer diameter of the extension shaft 60, is equal to or is no more than 1.0 F, 1.1 F, 1.2 F, 1.3 F, 1.4 F, 1.5 F, 1.6 F, 1.7 F, 1.8 F, 1.9 F, 2.0 F, 2.1 F, 2.2 F, 2.3 F, 2.4 F, 2.5 F, 2.6 F, 2.7 F, 2.8 F, 2.9 F, 3.0 F, or a value in the range between any two of the aforementioned values, preferably no more than 2.4 F.

The diameter of the extension piece lumen 62, where present, is sufficiently large to accommodate and permit slidable movement of a guidewire therein, and may depend on the gauge and length of guidewire employed. The lumen 62 diameter of the extension shaft 60 is the same as or similar to that of the catheter shaft 30, or may differ by 1 %, 2 %, 3 %, 4 %, 5 %, 6 %, 7 %, 8 % ,9 %, 10 %, 15 %, 20 %, 25 %, 30 %, 35 %, 40 %, 45 % or 50 % or a value in the range between any two of the aforementioned values. According to one aspect of the invention, the diameter of the extension piece lumen 62, where present, is equal to or no more than 10 %, 20 %, 30 %, 40 %, 50 %, 60 %, 70 %, 80 %, 90 % or 100 % larger than the external diameter of the guidewire, or a value in the range between any two of the aforementioned values, preferably between 10 % and 30 %. According to one aspect of the invention the diameter of the extension piece lumen 62, where present, is equal to or no more than 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm or 0.8, or a value in the range between any two of the aforementioned values, preferably between 0.3 and 0.6 mm.

The area disposed within the ellipse 8 in FIG. 7 is depicted in an enlarged view in FIG. 8, which shows the distal port 66 disposed with a connector 68 adapted to dismountably engage with the connector 40 of the catheter shaft 30. In this instance the connector comprises a receiving thread that extends along a lumen 62 in the extension shaft 60 in a proximal 55 direction. The screw thread, where implemented, may in equal alternative progress along the outside of the shaft 60, in a proximal direction from the distal end, depending on the configuration of the connector 40 of the catheter shaft 30. As mentioned elsewhere the coupling of the respective connectors 40, 68 advantageously permits the catheter to extend in length, without substantially increasing the profile of the multifunction catheter 100 at the connection region. By this means, the extended multifunction catheter can pass through a lumen of the second catheter without substantial hindrance. The same catheter may also be used to replace the guidewire and to deconvolute a tortuous path.

In FIG. 28 is illustrated a stiffening mandrel 140 that comprises an elongated shaft 142 having a proximal end 146 and distal end 144. It is configured for insertion into the multifunction catheter lumen 32, through the proximal port 36. The mandrel shaft 142 is flexible, and to provide pushability and rigidity, is preferably stiffened to at least the same degree as the stiffest part of the catheter shaft. The shaft 142 may be formed from a material having the requisite rigidity such as high and/or low density polyethylene, Polyamids, poly(ethylene terephthalate) (PET) or polyesters and copolymers thereof., stainless steel or a superelastic NiTi alloy. The distal tip of the mandrel 140 is preferably softened to allow insertion into the proximal port 36. The proximal end 146 of the mandrel may optionally be disposed with a handle 143. According to one aspect of the invention, the handle 143 acts as a limit stop that abuts the proximal port 36 in the inserted position and limits the length of mandrel 140 that passes through the lumen. In this way the position of the distal end 144 of the inserted stiffening mandrel 140 can be regulated. Preferably, the handle 143 is configured such that the distal end 144 of the mandrel 140 advances as far as the region proximal 20 to the side port 38 of the multifunction catheter 100. By doing so, a multifunction catheter 100 may advance along a guidewire threaded through the distal port 34 and out through the side port 38 when the stiffening mandrel 140 is in place. The handle 143 may be disposed with dismountable attachment means for dismountable attachment to the proximal end 20 of the multifunction catheter 100 which prevents slidable displacement of the mandrel 140 in lumen 32. The outer diameter of the mandrel shaft 142 is less than of the multifunction catheter lumen 32. It may by smaller by an amount equal to or more than 1 %, 2 %, 3 %, 4 %, 5 %, 6 %, 7 %, 8 %, 9 %, 10 %, 15 %„ 20 %, 25 %, 30 %, 35 %, 40 % or 50 % or a value in the range between any two of the aforementioned values. According to one aspect of the invention the diameter of the mandrel shaft 142 is equal to or no more than 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, or a value in the range between any two of the aforementioned values, preferably between 0.2 and 0.5 mm. The overall length of the stiffening mandrel 140 is typically about 90 to about 150 cm.

The multifunction catheter 100 may be provided as a kit that comprises the extension piece 200 and/or stiffening mandrel 140. Packaging and instructions may further be included.

The exchange of an in-place second catheter 28 with a replacement second catheter 21 is illustrated in the sequence of FIGS. 14 to 22. While the figures show the second catheter engaged with a guidewire 94 in an over-the-wire mode, the procedures and practices described herein may equally be adapted to replace a second catheter operating in a rapid exchange mode. In FIG. 14, the in-place guidewire 94 is disposed within a guidewire receiving inner lumen 93 of a second catheter 92 that may be a guiding catheter. The distal ends of both the in-place guidewire 94 and the second catheter 92 are located in a lumen 91 of a vessel 90 within the body, and the second catheter is to be replaced, for example, when the surgeon decides a narrower or longer guiding catheter is needed.

In FIG. 15, the proximal end of the in-place guidewire 94 is inserted, i.e. back-loaded, into the distal port 34 of the multifunction catheter 100 and through the inner lumen until the proximal end exits the side port 38. The proximal end of the guidewire may then be manually grasped and the multifunction catheter 100 advanced, as shown by the arrow in FIG. 15, over the in-place guidewire 94 and in through the proximal port 96 of the second catheter 92. The multifunction catheter is advanced through the second catheter lumen 93 until the distal tip of the multifunction catheter 100 reaches the distal end of the second catheter 92 as shown in FIG. 16. It is not necessary that the tip of the multifunction catheter 100 passes through the distal port 97 of the second catheter 92, though it is not excluded. At this point the extension piece 200 is attached via connectors 40, 68 to the multifunction catheter 100. The second catheter 92 may be withdrawn from vessel 90 over the multifunction catheter 100 as shown by the arrow in FIG. 17. It can be seen from FIG. 18 that the extension piece 200 may optionally be disposed with a handle 70 at the proximal end for the surgeon to grasp while the second catheter 92 is withdrawn. If necessary, the handle 70 can be removed to allow the second catheter 92 to pass entirely over the extension piece 200. FIG. 19 shows the multifunction catheter 100 wherein the handle 70 has been removed. After withdrawal, the multifunction catheter 100, extension 200 and guidewire 94 remain in situ (FIG. 19).

The proximal end of the extension piece 200 is introduced into the distal port 112 of a replacement second catheter 110 as shown by the arrow in FIG. 20. The replacement second catheter 110 is advanced over the proximal end of the extension piece 200 and multifunction catheter 100 as shown by the arrow in FIG. 21. After the proximal end of the replacement catheter 110 has been advanced past the proximal end of the extension piece 200 the handle 70 can be replaced as shown in FIG. 22. The advancement of the replacement second catheter 110 continues until the distal tip thereof extends out from the distal end of the multifunction catheter 100 into the patient's coronary artery. The multifunction catheter 100 may then be removed from the patient. Thus, by employing the multifunction catheter 100, the replacement second catheter 110 is placed the same location as the previous second catheter.

The placement of a second guidewire 102 adjacent to an in-place guidewire 94 using the multifunction catheter is illustrated in the sequence of FIGS. 23 to 27. The distal end of the in-place guidewire 94 is located in a lumen 91 of a vessel 90 within the body, and the distal end of the guidewire 94 is just distal to a stenosed region 95. The proximal end of the in-place guidewire 94 is inserted, i.e. back-loaded, into the distal port 34 of the multifunction catheter 100 and through the inner lumen until the proximal end exits the side port 38. The proximal end of the guidewire may then be manually grasped and the multifunction catheter 100 advanced over the in-place guidewire 94 until the radiopaque marker 39 is just distal to the stenosed region (e.g. by 5 mm) as shown in FIG. 23. While the marker 39 in FIGs. 23 to 26 coincides with the position of the side port 38, it will be appreciated that the marker 39 may equally be placed distal or proximal thereto e.g. by 1 to 3 mm as mentioned elsewhere herein. The position of the multifunction catheter 100 is maintained while the in-place guidewire 94 is carefully withdrawn proximally as shown by the arrow in FIG. 24 until its distal end exits the side port 38. The in-place guidewire 94 is pushed forward proximally as shown by the arrow in FIG. 25 until it is distal to the stenosed region 95. A second guidewire 102, preferably pre-loaded in the multifunction catheter, may then be advanced through the inner lumen of the multifunction catheter, until the guidewire extends from the distal guidewire port and into the vessel 90 as shown in FIG. 26. By grasping securely the second guidewire 102, the multifunction catheter 100 is then withdrawn proximally from the patient's arterial system, while the position of the second guidewire is maintained as shown in FIG. 27, so leaving in place two guidewires It is particularly preferred that the second guidewire 102 is of sufficient length that the proximal end can be grasped while the multipurpose catheter 100 is withdrawn. In other words, the length of second guidewire 102 exiting the subject, should be greater than the length of the multifunction catheter 100. It is noted the close proximity of the side port 38 to the distal port 34 in the multifunction catheter 100 allows the use in a vessel 90 when the region distal to the stenosed region 95 has restricted clearance - e.g. it is tortuous as illustrated in FIGs. 23 to 27.

A conventional catheter such as a guiding catheter, stent-delivery catheter or dilatation catheter cannot access a vessel when the route is tortuous or when calcium deposits block advancement. The multifunction catheter 100 of the invention is able to enter tortuous and calcified regions and deconvolute the vessel such that the conventional catheter can advance, when the multifunction catheter 100 is still in situ. The deconvolution of a tortuous route in a vessel using the multifunction catheter 100 is illustrated in the sequence of FIGS. 29 to 30. The distal end of the multifunction catheter 100 is placed in the convoluted lumen 91 of a vessel 90 within the body; its shape conforms to the bend 120. A stiffening mandrel 140 is inserted through the proximal port 36 of the multifunction catheter 100 and advanced along the lumen towards the distal end. In doing so, the shape of the multifunction catheter 100 at least partially restored towards a straight tube, which also deconvolutes (partially or completely straightens out) the bends in the vessel 90. It is noted that the extension piece 200 is not necessary. In FIG. 30, a handle 143 of the stiffening mandrel 140 is shown which does not act as a limit-stop described earlier; in other words, the mandrel 140 can advance all the way through the distal port without hindrance if necessary. However, a handle 143 that acts as a limit stop is not excluded from the scope of the invention. The narrow profile of the multifunction catheter 100 permits advancement of separate catheter in the vessel 90, while the multifunction catheter is still in situ (not illustrated).

When an in-place guidewire is to be replaced (not illustrated), the proximal end of the in- place guidewire is fed through the distal guidewire port 34 of the multifunction catheter 100 and out through the side port 38, and the multifunction catheter 100 is advanced along the guidewire, through the vasculature. A radiopaque marker 39 adjacent to the side port 38 allows the surgeon to position the side port distal to the stenosed region, for example, by a distance of 5 mm. The in-place guidewire is then withdrawn proximally from the patient's arterial system by pulling on the proximal end of the guidewire which extends out from the patient, while the position of the multifunction catheter is maintained. A replacement guidewire, preferably pre-loaded in the multifunction catheter 100, may then be advanced through the inner lumen 32 of the multifunction catheter 100, until the guidewire extends from the distal guidewire port 34 in the multifunction catheter. The multifunction catheter can then be withdrawn. It is noted that the extension piece 200 is not necessary.

When an in-place guidewire is to be replaced while an in-place second catheter (e.g. a guiding catheter) is engaged with the in-place guidewire, the proximal end of the in-place guidewire is fed through the distal guidewire port 34 of the multifunction catheter 100 and out through the side port 38, and the multifunction catheter 100 is advanced along the guidewire and through the second catheter, until the distal tip is well within the lumen of the second catheter, or more preferably, until the distal tip exits the second catheter at a distal port (not illustrated). A radiopaque marker 39 adjacent to the side port 38 allows the surgeon to position the side port distal to the stenosed region, for example, by a distance of 5 mm. The in-place guidewire is then withdrawn proximally from the patient's arterial system by pulling on the proximal end of the guidewire which extends out of the patient, while the position of the multifunction catheter 100 is maintained. A replacement guidewire, preferably pre-loaded in the multifunction catheter, may then be advanced through the inner lumen 32 of the multifunction catheter, until the guidewire extends from the distal guidewire port 34 in the multifunction catheter. The multifunction catheter 100 can then be withdrawn through the lumen of the second catheter. It is noted that the extension piece 200 is not necessary.

The multifunction catheter 100 of the invention can be used to deliver medicament to the site of treatment. The connector 40 at the proximal end 20 of the multifunction catheter 100 is attached to a fluid delivery fitting such as a Luer connector. Alternatively, a Luer fitting may be directly attached to the proximal end 20 of the multifunction catheter 100. The connector can be coupled to a syringe or tubing for the passage of liquid medicament, which advances along the inner lumen 32 towards the distal end 10 of the multifunction catheter 100. The medicament exits from the distal port 34 and the side port 38. Advantageously, the close proximity of the side port 38 to the distal port 34 in the multifunction catheter 100 allows the delivery to a stenosed region of a vessel when the region distal to the stenosed region has restricted clearance - e.g. it is tortuous.

Those skilled in the art will recognize that other modifications and improvements can be made to the invention without departing from the scope thereof.