Method for treating lesions and devices and systems for same

Abstract

A guidewire for treating a blood vessel of a mammalian body comprising an elongate member having a distal portion adapted for insertion into the blood vessel for travel to a lesion and a proximal portion configured to control movement of the distal portion during travel in the blood vessel. First and second electrodes are mounted on the distal portion. An electrically- insulated conductive lead is electrically coupled to each of the electrodes and extends from the distal portion to the proximal portion. The lead is adapted for coupling to a radio frequency generator for supplying radio frequency energy to at least one of the first and second electrodes for delivery to the lesion to create a space in the lesion to permit further advancement of the distal portion relative to the lesion.

Description

METHOD FOR TREATING LESIONSAND DEVICES AND SYSTEMS FOR SAMECROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to U.S. provisional patent application Serial No. 63 / 630,077 filed December 29, 2023 and U.S. provisional patent application Serial No. 63 / 630,466 filed February 5, 2024, the entire content of each of which is incorporated herein by this reference.FIELD OF INVENTION

[0002] This invention relates to treating occluded vessels in a mammalian body, and more particularly treating occluded blood passageways in a mammalian body.BACKGROUND OF THE INVENTION

[0003] The recanalization of vascular occlusions, including chronic total occlusions (CTO), typically requires the occlusion to be initially traversed with a guidewire for subsequent delivery of therapeutic devices such as balloons and stents. Depending on the characteristics of the occlusion, this can be a difficult, expensive, and time-consuming process.

[0004] In this regard, guidewires typically have fixed properties specifically with respect to the flexibility of the distal portion of the guidewire. Guidewires are often characterized according to the stiffness of this distal portion, for example according to the gram stiffness of its distal tip. A 5.0-gram guidewire will have a stiffer distal tip than a 3.5-gram guidewire. A CTO guidewire will typically have a stiffer distal tip to address harder lesions and a support guidewire will typically have a stiffer distal end to accommodate bulkier devices. Consequently, in order to address a number of different occlusion types, a large inventory of guidewires is typically required.

[0005] In general, the selection of the guidewire for a particular occlusion is dependent upon the perceived characteristics of the occlusion. For example, a hard occlusion often requires the selection of a stiffer guidewire to aid in penetrating the occlusion. Typically, a physician will start with a guidewire having a soft or flexible tip for safety and to garner some tactile feedback on the characteristics of the occlusion and will then incrementally select a guidewire with a stiffer tipbased on the characteristics of that occlusion. Th i s oftentimes requires the use of multiple guidewires until the occlusion is eventually penetrated. In addition, to properly align the tip of the guidewire towards its intended direction, a curve or bend is usually made to the distal tip of the guidewire to help in this alignment. This reshaping of the distal tip is often required multiple times and requires that the guidewire be removed from the body multiple times to incrementally reshape its distal tip, prolonging the time required to traverse the occlusion. Additionally, since the distal tip is relatively flexible with respect to the occlusion, a guidewire often has minimal stability and can be easily deflected off course by the characteristics of the occlusion during advancement of the guidewire.

[0006] The use of a lithotripsy balloon to treat calcified lesions by creating fissures in the lesion is well known. Such balloons can allow subsequent delivery of therapeutic devices such as balloons and stents to make the lesion more amenable to such treatment. Current devices rely on using energy, for example RF energy delivered by a balloon catheter, to create shockwaves which can create fissures in the lesion. However, these devices deliver the RF energy via a balloon catheter. One of the drawbacks of current lithotripsy balloon catheters is the stiffness of the catheter, which can inhibit advancement of the catheter to the targeted lesion. In one current lithotripsy procedure, for example, a flexible guidewire is first inserted across a lesion and then is followed by the stiffer lithotripsy balloon catheter. In tortuous lesions, the lithotripsy balloon catheter sometimes cannot follow the track of the flexible guidewire due to the disparity in the flexibility of the guidewire and the catheter, for example the radius of curvature of the catheter is greater than the radius of curvature of the guidewire. In some cases, the catheter and may even kink at the transition point so the device cannot be advanced across the lesion.

[0007] The use of drug eluting balloons to localize drug delivery to a lesion site is known. Some current devices deliver the drug by coating the outside surface of a balloon with the drug and relying on passive diffusion to deliver the drug from the balloon to the lesion site upon inflation of the balloon within the vasculature. One of the drawbacks of current drug eluting balloons is that much of the drug washes off the balloon during delivery to the target site and, consequently, less drug is actually delivered to the lesion site. In addition, this wash out of the drug is not controllable and thus there can be inconsistent results. Another drawback, when used for example in hard lesions such as calcified lesions, is that the drug is sometimes unable todiffuse through the calcified layer and consequently is unable to diffuse deep into the vascular wall.

[0008] What is needed are devices that can more efficiently traverse and treat an occlusion in a vessel of a mammalian body and reduce the need for significant inventory. Further needed is a more deliverable device that can access more tortuous lesions.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The drawings herein are schematic and not drawn to scale and are for illustration purposes only and are not intended to limit the scope of the present disclosure.

[0010] FIG. l is a cross-sectional view of an embodiment of a bipolar ablation guidewire of the invention.

[0011] FIG. 2 is a cross-sectional view of the bipol oar ablation guidewire of FIG. 1 taken along the line 2-2 of FIG. 1.

[0012] FIG. 3 is a cross-sectional view, similar to FIG. 2, of another embodiment of the bipolar ablation guidewire of FIG. 1.

[0013] FIG. 4 is a cross-sectional view of the distal portion of another embodiment of the bipolar ablation guidewire of the invention.

[0014] FIG. 5 is a cross-sectional view, similar to FIG. 4, of the distal portion of another embodiment of the bipolar ablation guidewire of the invention.

[0015] FIG. 6 is a cross-sectional view, similar to FIG. 4, of the distal portion of another embodiment of the bipolar ablation guidewire of the invention.

[0016] FIG. 7 is a cross-sectional view, similar to FIG. 4, of the distal portion of another embodiment of the bipolar ablation guidewire of the invention.

[0017] FIG. 8 is a cross-sectional view of the distal portion of an embodiment of a single pole ablation guidewire of the invention disposed within an embodiment of a delivery catheter of the invention.

[0018] FIG. 9 is a cross-sectional view of the distal portion of the single pole ablation guidewire of FIG. 8 within another embodiment of a delivery catheter of the invention.

[0019] FIG. 10 is a cross-sectional view of the distal portion of another embodiment of a single pole ablation guidewire of the invention disposed within the delivery catheter of FIG. 9, without the electrode leads shown.

[0020] FIG. 11 is a side elevational view of the single pole ablation guidewire of FIG. 9 within the delivery catheter of FIG. 9, without the electrode leads shown.

[0021] FIG. 12 is a side elevational view of another embodiment of the single pole ablation guidewire of the invention within the delivery catheter of FIG. 9, without the electrode leads shown.

[0022] FIG. 13 is a perspective view of the distal end of another embodiment of a single pole ablation guidewire of the invention disposed within the delivery catheter of FIG. 9.

[0023] FIG. 14 is a cross-sectional view of the single pole ablation guidewire of FIG. 13 taken along the line 14-14 of FIG. 13.

[0024] FIG. 15 is a cross-sectional view of the distal portion of another embodiment of a bipolar ablation guidewire of the invention.

[0025] FIG. 16 is a cross-sectional view of an embodiment of a treatment guidewire of the invention.

[0026] FIG. 17 is a side elevational view of another embodiment of a treatment guidewire of the invention.

[0027] FIG. 18 is a side elevational view of the treatment guidewire of FIG. 17 disposed within an embodiment of a treatment catheter of the invention for forming an embodiment of a treatment device of the invention.

[0028] FIG. 19 is a cross-sectional view of the treatment device of FIG. 18 taken along the line 19-19 of FIG. 18.

[0029] FIG. 20 is a cross-sectional view, similar to FIG. 19, of another embodiment of a treatment device similar to the treatment device of FIG. 18.

[0030] FIG. 21 is a side elevational view of the treatment guidewire of FIG. 17 disposed within an embodiment of a treatment ballon catheter of the invention for forming an embodiment of a treatment device of the invention.

[0031] FIG. 22 is a side elevational view of the treatment guidewire of FIG. 17 disposed within an embodiment of a drug-eluting treatment ballon catheter of the invention for forming an embodiment of a treatment device of the invention.

[0032] FIG. 23 is a side elevational view of the treatment guidewire of FIG. 17 disposed within another embodiment of a drug-eluting treatment ballon catheter of the invention for forming another embodiment of a treatment device of the invention.

[0033] FIG. 24 is a side elevational view of the treatment guidewire of FIG. 17 disposed within another embodiment of a drug-eluting treatment ballon catheter of the invention for forming another embodiment of a treatment device of the invention.

[0034] FIG. 25 is a side elevational view of the treatment guidewire of FIG. 17 disposed within another embodiment of a treatment ballon catheter of the invention, in a first position, for forming another embodiment of a treatment device of the invention.

[0035] FIG. 26 is a side elevational view of the treatment guidewire of FIG. 17 disposed within the treatment ballon catheter of FIG. 26, in a second position.

[0036] FIG. 27 is a side elevational view of a guidewire disposed within another embodiment of a treatment balloon catheter of the invention, for forming another embodiment of a treatment device of the invention.

[0037] FIG. 28 is a cross-sectional view of a portion of the treatment balloon catheter or FIG. 27 taken along the line 28-28 of FIG. 27.

[0038] FIG. 29 is a cross-sectional view of a portion of the treatment balloon catheter or FIG. 27 taken along the line 29-29 of FIG. 27.

[0039] FIG. 30 is a cross-sectional view, similar to FIG. 29, of a portion of another embodiment of the treatment balloon catheter of the invention.

[0040] FIG. 29 is a cross-sectional view of a portion of the treatment balloon catheter or FIG. 27 taken along the line 29-29 of FIG. 27.

[0041] FIG. 31 is a cross-sectional view of a portion of the treatment device of FIG. 27 taken along the line 31-31 of FIG. 27.

[0042] FIG. 32 is a side elevational view of a guidewire disposed within another embodiment of a treatment balloon catheter of the invention, for forming another embodiment of a treatment device of the invention.

[0043] FIG. 33 is a side elevational view of a guidewire disposed within another embodiment of a treatment balloon catheter of the invention, for forming another embodiment of a treatment device of the invention.

[0044] FIG. 34 is a perspective view of a treatment component of a treatment device of the invention.DETAILED DESCRIPTION OF THE INVENTION

[0045] The device of the invention can be used for treating a vessel of a mammalian body, for example a blood passageway or blood vessel of a mammalian body. The mammalian body can be a human body. Such treatment can provide better access to the lesion, passage of the lesion, recanalization of the occlusion, treatment of the vessel or any combination of the foregoing. The vessel to be treated can include a lesion that partially or totally occludes the vessel. The device can include an ablation guidewire of the invention that can be configured, possibly among other things, to modify the lesion or occlusion. Such lesion modification can, for example, serve to accommodate the ablation guidewire rather than requiring the use of one or more other guidewires to accommodate characteristics of the lesion or occlusion. The ablation guidewire can optionally be referred to as a delivery guidewire or delivery ablation guidewire. The ablation guidewire can optionally be inserted into the vessel with the aid of a catheter, for example a microcatheter or delivery catheter, to aid in delivery of the ablation guidewire to the lesion by providing support to the ablation guidewire.

[0046] The device of the invention can deliver radio frequency [RF] energy with sufficient energy to modify the lesion or occlusion, for example instead of requiring another guidewire with different characteristics to accommodate the lesion or occlusion. Thus, a single ablation guidewire can often be utilized to modify a lesion or occlusion irrespective of the characteristics of the lesion or occlusion. The ablation guidewire can optionally have an outer diameter ranging from 0.014 to 0.038 inches, but can optionally be smaller or larger depending upon the size and location of the vessel being treated. The device of the invention can deliver RF energy to the lesion in any suitable manner. For example, the device can include any suitable bipolar arrangement of electrodes, including one or more electrodes on the distal tip of the guidewire, one electrode on the distal tip and another proximal of such distal electrode on the distal portion of the guidewire, one on the distal tip of the guidewire and another on the exterior or interior of the delivery catheter and one on the distal tip of the guidewire and another on the exterior of the patient.. Any plurality of electrodes on the distal tip of the guidewire can be in a variety of configurations, for example two electrodes that are positioned side by side to each other. The distal electrodes can include one or more ball electrodes, one or more semispherical electrodes, one or more loop electrodes and one or more semicircular or C-shaped electrodes.

[0047] The device of the invention can optionally include a catheter of any suitable type for treating the lesion. The treatment catheter can be of any suitable type, for example any suitable balloon catheter, any suitable drug eluting ballon catheter, any suitable scoring catheter, any suitable RF emitting balloon catheter or any combination of the foregoing. The treatment catheter can optionally be delivered to the lesion in any suitable manner, for example optionally over an ablation guidewire of the invention or optionally over a conventional guidewire, it being appreciated that a treatment procedure involving a treatment catheter need not be preceded by a treatment involving an ablation guidewire of the invention. The treatment catheter can optionally have an outer diameter ranging from 0.7 to 4.0 millimeters, but can optionally be smaller or larger depending upon the size and location of the vessel being treated. In this regard, any delivery catheter can be withdrawn from the vessel to permit insertion of the treatment catheter into the vessel and travel over the ablation guidewire to the lesion. Once the treatment catheter has been properly positioned over the ablation guidewire with respect to the lesion, the ablation guidewire of the invention can optionally be withdrawn from the treatment catheter and vessel to permit any suitable other guidewire, for example a treatment guidewire of the invention, to be introduced through the catheter during treatment of the lesion. The treatment guidewire can optionally be referred to as an ablation guidewire or treatment ablation guidewire. The treatment guidewire of the invention can be utilized to enhance treatment of the lesion by the treatment catheter. For example, the treatment guidewire can deliver RF energy to the balloon or other treatment catheter, through the balloon or other treatment catheter or both. The treatment guidewire can optionally be provided with any suitable number of electrodes for delivering RF energy to the treatment catheter. The electrodes of the treatment guidewire can optionally be any suitable number of annular electrodes, for example proximal of the distal tip of the treatment guidewire. The treatment catheter can optionally be provided with any suitable number of conductive elements for engaging respective electrodes of the guidewire for receiving RF energy from the guidewire. Such RF energy from the guidewire can optionally be delivered by the treatment catheter to the lesion. When the treatment catheter is a drug eluting catheter, for example a drug eluting balloon catheter, such delivered RF energy can enhance deep imbedding and retention of the drug within the vascular wall.

[0048] Such delivery of RF energy from an RF generator to the treatment site through a guidewire, for example a treatment guidewire of the invention having leads coupled to an RFgenerator, instead of through a treatment catheter, can allow the balloon or other treatment catheter to be more flexible and thus facilitate delivery of the treatment catheter to more tortuous lesions. Further, it is generally easier to exchange a guidewire inside a lumen of a catheter in situ than to track the catheter or other treatment device over the outside of a guidewire in situ since the treatment device will encounter more friction from the lesion than the guidewire will encounter from the inside of a catheter, which is typically lined for lubricity.

[0049] Any balloon treatment catheter of the invention can be configured to score the lesion upon inflation of the balloon to enhance treatment of the lesion, for example to enhance delivery within the lesion of any drug provided by the catheter. In this regard, the treatment catheter of the invention can be provided with protruding elements of any suitable type for scoring the lesion, for example by being urged against the lesion by the inflated balloon of the treatment catheter. Such protruding elements, which can optionally be referred to as piercing or scoring elements, can optionally be provided with an edge or other projection for scoring the lesion. Any protruding element of a treatment catheter of the invention can optionally include one or more suitable electrodes for delivering RF energy to the scored lesion.

[0050] The treatment device of the invention can optionally include an ablation guidewire of any suitable type for treating a lesion in a blood vessel of a mammalian body, for example for treating a lesion or traversing an occlusion formed by a lesion. A suitable ablation guidewire can include an elongate member 42 extending along a longitudinal axis 43 and having a proximal portion 42a and a distal portion 42b (see FIGS. 1-3). The elongate member can be made from any suitable metal, for example stainless steel, nitinol, and platinum, plus any suitable electrically-insulating material, for example a suitable polymer such as nylon, polyethylene, polyurethane, polyimide, polytetrafluoroethylene (PTFE), poly etheretherketone (PEEK) and Pebax. Such an insulating material typically forms the outer layer or surface of the elongate member. The elongate member can have an outer diameter optionally ranging from 0.008 to 0.118 inches or optionally from 0.014 inches to 0.038 inches. The distal portion is optionally less stiff than the proximal portion of the elongate member, a more flexible distal tip facilitating navigation of the ablation guidewire through the turns and obstructions of a vessel. The distal portion 42b, which can include a distal tip 44, is adapted for insertion into the blood vessel for travel to the lesion and the proximal portion 42a is configured to control movement of the distal portion during travel in the blood vessel.

[0051] At least one electrode is carried by the distal portion 42b. When the ablation guidewire of the invention is a bipolar ablation guidewire, first and second electrodes are mounted on the distal portion 42b. At least one of the electrodes can optionally be mounted on the distal tip 44 of the elongate member. Optionally, both electrodes can be mounted on the distal tip. An electrode on the distal tip can optionally be referred to as a distal tip electrode, distal electrode or tip electrode. A distal electrode can have any suitable shape, including a ball, a sphere, a semi sphere, two rings in a cross shape, a micro loop, a ring, a cross shape that tapers distally, a semicircle, a C-shape, an L-shape and any combination of the foregoing. The electrodes can be made of any suitable conductive metal, including any of the conductive metals utilized for conventional RF or other electrodes. An electrically-insulated conductive lead is carried by the elongate member and is electrically coupled to each electrode of the guidewire. The leads can be of any suitable type, include a wire, a braid or shield, a helix and a hypotube. Each lead extends from the distal portion 42b to the proximal portion 42a of the elongate member and is adapted for coupling to a radio frequency generator 46, for example by means of connector 47, for radio frequency energy to be delivered to the respective electrode of the guidewire. RF generator 46 typically includes a controller or modulating its supply of radio frequency energy. The generator 46 can optionally be configured to deliver RF energy with voltages ranging from 1000 to 3000 volts or greater than 3000 volts. The generator 46 can optionally be configured to deliver radio frequency energy in pulses, which pulses can optionally be in micro seconds, nano seconds, pico seconds or any combination of the foregoing. The generator 46 optionally has multiple delivery settings. The ablation guidewires of the invention can be utilized with any suitable delivery catheter, including any of the delivery catheters disclosed herein, and together can form a treatment device or system of the invention.

[0052] An optional embodiment of a bipolar ablation guidewire 51 of the invention is shown in FIGS. 1-3. Guidewire 51 includes first and second electrodes carried by distal portion 42b of the elongate member 42, and more specifically by distal tip 44 of the elongate member. The electrodes optionally serve as a bipolar pair of electrodes. First distal electrode 52 and second distal electrode 53 optionally extend forwardly or distally of the distal tip 44. The electrodes are made of any suitable material, optionally including stainless steel, nitinol or platinum. The electrodes optionally extend forwardly or distally of tip 44 the same distance. The electrodes 52, 53 optionally extend side by side or adjacent to each other forward of the distal tip. At least oneof the distal electrodes, and optionally both of the distal electrodes, are ball or spherical electrodes, which are optionally solid. A separate conductive lead 54 extends through the elongate member 42 for each of the electrodes 52, 53 for connecting the electrode to the RF generator 46. The leads 54 are made from any suitable material, optionally including stainless steel, nitinol, platinum or copper. At least one of the electrodes 52, 53 is an active electrode, and optionally both of the electrodes are active electrodes. The RF generator can optionally be configured to selectively or alternatively deliver RF energy in any suitable pulsed manner to one of the electrodes, including as disclosed herein, with the other electrode serving as the return electrode. The application of RF energy to the electrodes can optionally create a spark 56, which can optionally serve to disintegrate part of the lesion so as to create a space therein for further advancement or movement of the guidewire. Guidewire 51 can be utilized with any suitable delivery catheter, including any of the delivery catheters disclosed herein, and together can form a treatment device or system of the invention. Since electrodes 52, 53 are located close to one another, this bipolar arrangement can allow the use of higher voltages since the energy is confined to this location, as opposed to for example through the body in the case of an external patch.

[0053] The elongate member 42 can be of any suitable configuration or construction. For example, the elongate can be a single tubular member 61 provided with first and second bores or passageways 62 for receiving respective conductive leads 54 (see FIG. 2). Alternatively, the elongate member 42 can be formed from first and second tubular members 66, each having a bore or passageway 67 for receiving a conductive lead 54 of the ablation guidewire 51. The tubular members 61, which can optionally be referred to as members, can be secured or formed together in any suitable manner, for example by twisting the tubular members 66 or by means of a suitable interconnector 63 extending the length of the elongate member 42 between the tubular members 61. The interconnector can optionally be an adhesive, a tie layer or a bond.

[0054] An optional embodiment of a bipolar ablation guidewire 76 of the invention is shown in FIG. 4. Guidewire 76, which is substantially similar to guidewire 51, and like reference numerals have been used to identify like components of the guidewires 51 and 76. Guidewire 76 includes first and second electrodes carried by distal portion 42b of the elongate member 42, and more specifically by distal tip 44 of the elongate member. The electrodes optionally serve as a bipolar pair of electrodes. First distal electrode 77 and second distal electrode 78 optionallyextend forwardly or distally of the distal tip 44. The electrodes optionally extend forwardly or distally of tip 44 the same distance. The electrodes 77, 78 optionally extend side by side or adjacent to each other forward of the distal tip. At least one of the distal electrodes, and optionally both of the distal electrodes, can be described as semicircular in shape, arcuate or arched in shape or C-shaped. The electrodes 77, 78 optionally face each other, or open towards each other, and when viewed together can optionally be described as two spaced-apart semicircles extending in a plane that together form a circle having a space or gap 81 between the two semicircles. When viewed together, electrodes 77, 78 can optionally be referred to as a microloop bipolar pair of electrodes. Each of the electrodes has an arched distal end 82, with the respective ends 82 of the two electrodes separated by the gap 81. A separate conductive lead 83 extends through the elongate member 42 for each of the electrodes 77, 78 for connecting the electrode to the RF generator 46, not shown in FIG. 4. The electrodes and leads of guidewire 76 can optionally be made from the same materials as the electrodes and leads of guidewire 51. At least one of the electrodes 77, 78 is an active electrode, and optionally both of the electrodes are active electrodes. The RF generator can optionally be configured to selectively or alternatively deliver RF energy in any suitable pulsed manner to one of the electrodes, including as disclosed herein, with the other electrode serving as the return electrode. The application of RF energy to the electrodes can optionally create a spark 84, which can optionally serve to disintegrate part of the lesion so as to create a space therein for further advancement or movement of the guidewire. The elongate member 42 of ablation guidewire 76 can be of any suitable configuration or construction, including for example a single tubular member, like tubular member 61 in FIG. 2, or first and second tubular members, like tubular members 66 in FIG. 3. The microloop bipolar pair of electrodes 77, 78, which optionally extend in a plane, are able to better “shear” through an occlusion than a conventional guidewire and are less prone to being deflected by an occlusion than a conventional guidewire. Guidewire 76 can be utilized with any suitable delivery catheter, including any of the delivery catheters disclosed herein, and together can form a treatment device or system of the invention.

[0055] An optional embodiment of a bipolar ablation guidewire 91 of the invention is shown in FIG. 5. Guidewire 91, which is substantially similar to guidewire 76, and like reference numerals have been used to identify like components of the guidewires 76 and 91. The guidewire 91 includes first and second electrodes carried by distal portion 42b of the elongatemember 42, and more specifically by distal tip 44 of the elongate member. The electrodes optionally serve as a bipolar pair of electrodes. First distal electrode 92 and second distal electrode 93 optionally extend forwardly or distally of the distal tip 44. The electrodes optionally extend forwardly or distally of tip 44 the same distance. The electrodes 92, 93 optionally extend side by side or adjacent to each other forward of the distal tip. At least one of the distal electrodes, and optionally both of the distal electrodes, can be described as L-shaped. Each of the electrodes optionally has a first portion 94 extending radially outwardly from the distal portion 44 of the elongate member and a second portion 96 angled relative to the first portion and extending radially inwardly towards distal portion 44 and longitudinal axis 43. Each portion 94, 96 optionally extend in a line. Each second portion 96 is optionally inclined at an angle, for example substantially at a right angle, relative to the respective first portion 94. The electrodes 92, 93 optionally face each other, or open towards each other, and when viewed together can optionally be described as two spaced-apart right angle electrodes extending in a plane that together form a rectangle or square having a space or gap 97 between the two angled electrodes. Each of the electrodes has a distal end 98, with the respective ends 98 of the two electrodes separated by the gap 97. The electrodes can be made of any suitable conductive metal, including any of the conductive metals utilized for conventional RF or other electrodes. A separate conductive lead 99 extends through the elongate member 42 for each of the electrodes 92, 93 for connecting the electrode to the RF generator 46, not shown in FIG. 5. The electrodes and leads of guidewire 91 can optionally be made from the same materials as the electrodes and leads of guidewire 51. At least one of the electrodes 92, 93 is an active electrode, and optionally both of the electrodes are active electrodes. The RF generator can optionally be configured to selectively or alternatively deliver RF energy in any suitable pulsed manner to one of the electrodes, with the other electrode serving as the return electrode. The application of RF energy to the electrodes can optionally create a spark 101, which can optionally serve to disintegrate part of the lesion so as to create a space therein for further advancement or movement of the guidewire. The elongate member 42 of ablation guidewire 91 can be of any suitable configuration or construction, including for example a single tubular member, like tubular member 61 in FIG. 2, or first and second tubular members, like tubular members 66 in FIG. 3. The bipolar pair of electrodes 92, 93, which optionally extend in a plane, are able to better “shear” through an occlusion than a conventional guidewire and are less prone to being deflectedby an occlusion than a conventional guidewire. Guidewire 91 can be utilized with any suitable delivery catheter, including any of the delivery catheters disclosed herein, and together can form a treatment device or system of the invention.

[0056] An optional embodiment of a bipolar ablation guidewire 106 of the invention is shown in FIG. 6. Guidewire 106 is substantially identical to guidewire 76 and like reference numerals have been used to identify like components of the guidewires 76 and 106. A dielectric element 107 is disposed in the space 81 between the arched distal end 82 of the two electrodes 77, 78, and secured to the electrodes by any suitable means such as an adhesive. The dielectric element 107 can be made from any suitable material, including a suitable ceramic and any suitable polymer such as nylon, polyethylene, polyurethane, polyimide, polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK) and Pebax. At least one of the electrodes 77, 78 is an active electrode, and optionally both of the electrodes are active electrodes. The RF generator can optionally be configured to selectively or alternatively deliver RF energy in any suitable pulsed manner to one of the electrodes, including as disclosed herein, with the other electrode serving as the return electrode. The application of RF energy to the electrodes can optionally create a spark 108, which can optionally serve to disintegrate part of the lesion so as to create a space therein for further advancement or movement of the guidewire. Dielectric element 107 provides a barrier which can induce the spark 108 to occur around and in front of the dielectric element. In this regard, an electrical current will seek the path of least resistance so in the presence of a strong dielectric, like dielectric element 107, the current will tend to flow in front of and around the dielectric since blood provides less resistance than a dielectric. The elongate member 42 of ablation guidewire 106 can be of any suitable configuration or construction, including for example a single tubular member, like tubular member 61 in FIG. 2, or first and second tubular members, like tubular members 66 in FIG. 3. Guidewire 106 can be utilized with any suitable delivery catheter, including any of the delivery catheters disclosed herein, and together can form a treatment device or system of the invention.

[0057] An optional embodiment of a bipolar ablation guidewire 111 of the invention is shown in FIG. 7. Guidewire I l l is substantially identical to guidewire 76 and like reference numerals have been used to identify like components of the guidewires 76 and 111. A dielectric member 112 extends through at least a portion of the distal portion 42b of the elongate member 42 and has a portion 113 extending forwardly, beyond or distally of distal tip 44 that extendsbetween the electrodes 77, 78. The dielectric portion 1 13 optionally extends between the open face of the electrodes 77, 78, optionally through gap 81 between the arched, distal ends 82 of the electrodes. The dielectric portion 113 optionally extends a short distance forwardly, beyond or distally the electrodes 77, 78, for example approximately one millimeter. At least one of the electrodes 77, 78 is an active electrode, and optionally both of the electrodes are active electrodes. The RF generator can optionally be configured to selectively or alternatively deliver RF energy in any suitable pulsed manner to one of the electrodes, with the other electrode serving as the return electrode. The application of RF energy to the electrodes can optionally create a spark 114, which can optionally serve to disintegrate part of the lesion so as to create a space therein for further advancement or movement of the guidewire. Dielectric member 112, including dielectric portion 113, provides a barrier which can induce the spark 114 to occur around and in front of the dielectric member 112, as discussed above with respect to dielectric element 107. The forwardly extending dielectric portion 113 enhances the barrier and thus the size of the spark. The elongate member 42 of ablation guidewire 111 can be of any suitable configuration or construction, including for example a single tubular member, like tubular member 61 in FIG. 2 but with an additional central bore 62 in at least the distal portion 42b of the elongate member 42 for receiving the dielectric member 112, or first and second tubular members, like tubular members 66 in FIG. 3, optionally secured together by the dielectric member 112 in at least the portion of the elongate member 42 having the dielectric member. Guidewire 111 can be utilized with any suitable delivery catheter, including any of the delivery catheters disclosed herein, and together can form a treatment device or system of the invention.

[0058] A single pole ablation guidewire of the invention can include an elongate member 122 extending along a longitudinal axis 123 and having a proximal portion and a distal portion 122a (see FIGS. 8-14, where the proximal portion is not shown). The elongate member 122 can be made from any suitable metal, for example stainless steel, nitinol, and platinum, plus any suitable electrically-insulating material, for example a suitable polymer such as nylon, polyethylene, polyurethane, polyimide, polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK) and Pebax. Such an insulating material typically forms the outer layer or surface of the elongate member. The elongate member can have a diameter optionally ranging from 0.008 to 0.118 inches or optionally ranging from 0.014 inches to 0.038 inches. The distal portion is optionally less stiff than the proximal portion of the elongate member, a more flexible distal tipfacilitating navigation of the ablation guidewire through the turns and obstructions of a vessel. The distal portion 122a, which can include a distal tip 124, is adapted for insertion into the blood vessel for travel to the lesion and the proximal portion is configured to control movement of the distal portion during travel in the blood vessel. An electrode is carried by the distal portion 122b of the guidewire. The electrode can optionally be mounted on the distal tip 124. Such electrode can optionally be referred to as a distal tip electrode or tip electrode. A tip electrode can have any suitable shape, including a ball, a sphere, a semi sphere, two rings in a right angle cross shape, a micro loop, a ring, a cross shape that tapers distally, a semicircle, a C-shape, an L-shape and any combination of the foregoing. The electrode can be made of any suitable conductive metal, including any of the conductive metals utilized for conventional RF or other electrodes. An electrically-insulated conductive lead 126 of any suitable type is carried by the elongate member 122 and is electrically coupled to the electrode of the guidewire. The lead 126 can be of any suitable type, include a wire, a braid or shield, a helix and a hypotube. The lead extends from the distal portion 122a to the proximal portion of the elongate member and is adapted for coupling to a suitable radio frequency generator, for example RF generator 46 in FIG. 1, to cause radio frequency energy to be delivered to the electrode of the guidewire in any suitable manner, including as disclosed herein.

[0059] An optional embodiment of a single pole ablation guidewire 127 of the invention is shown in FIGS. 8, 9 and 11. Guidewire 121 includes a loop, micro loop or ring electrode 128 at the distal tip 124 of the elongate member. The electrode 128 can have any suitable outer diameter, for example optionally ranging from 0.008 to 0.118 inches or optionally ranging from 0.014 to 0.038 inches. The electrode can be made of any suitable conductive metal, including any of the conductive metals utilized for conventional RF or other electrodes. The conductive lead 126 is electrically connected to the electrode 128 and extends proximally to the proximal portion of the elongate member 122.

[0060] A single pole ablation guidewire of the invention can optionally be paired with any suitable catheter, for example during introduction of the guidewire through the vessel to the treatment site. The catheter, which can optionally be referred to as a microcatheter or delivery catheter, can be formed from an elongate tubular member 136 made from any suitable any suitable electrically-insulating material, for example a suitable polymer such as nylon, polyethylene, polyurethane, polyimide, polytetrafluoroethylene (PTFE), polyetheretherketone(PEEK) and Pebax. The tubular member 136 has a distal portion 136a. The tubular member has an outer diameter suitable for insertion into and passage through a blood vessel, for example optionally ranging from 0.7 to 6.7 millimeters or optionally ranging from 0.7 to 4.0 millimeters. The tubular member is provided with an internal passageway 137 having a diameter optionally ranging from 0.008 to 0.118 inches or optionally ranging from 0.014 to 0.038 inches.Passageway 137 ends at an opening 138 provided in the distal portion 136a of the elongate tubular member 136. The internal passageway 137 and the guidewire to be utilized with the catheter are appropriately sized so that the guidewire can slide longitudinally within the catheter.

[0061] The catheter can optionally be provided with at least one electrode, which can optionally pair with the tip electrode of the single pole ablation guidewire, to form a bipolar pair of ablation electrodes. The electrode is optionally provided on the distal portion 136a of the tubular member 136, optionally near the distal end of the tubular member. The electrode can optionally be on the outside of the tubular member 136. The electrode can optionally be on the inside of the tubular member, for example in passageway 137. An electrically-insulated conductive lead of any suitable type is carried by the catheter and is electrically coupled to the electrode of the catheter. The conductive lead can be of any suitable type, including a wire, a braid or shield, a helix and a hypotube, and made from any suitable material optionally including stainless steel, nitinol, platinum or copper. The lead extends from the distal portion 136a to the proximal portion of the tubular member and is adapted for coupling to a suitable radio frequency generator, for example RF generator 46 in FIG. 1, to cause radio frequency energy to be delivered to the electrode of the catheter. At least one of the tip electrode of the guidewire and the electrode of the catheter is an active electrode, and optionally both of the electrodes are active electrodes. The RF generator can optionally be configured to selectively or alternatively deliver RF energy in any suitable pulsed manner to one of the electrodes, including as disclosed herein, with the other electrode serving as the return electrode. The application of RF energy to the electrodes can optionally create a spark 139, which can optionally serve to disintegrate part of the lesion so as to create a space therein for further advancement or movement of the guidewire. To facilitate the creation of a spark, the surface area of the electrode of the single pole ablation guidewire, for example the tip electrode of the guidewire, is less than the surface area of the electrode of the catheter. For example, the surface area of the tip electrode relative to the surface area of the catheter electrode can optionally range from 1% to 30% or optionally lessthan 10%. The ablation guidewire and associated catheter form a device or system of the invention.

[0062] An optional embodiment of a delivery catheter 146 of the invention is shown in FIG. 8. Catheter 146 includes an electrode, for example an annular electrode 147, provided on the inner surface of the tubular member 136 forming internal passageway 137. Electrode 147 is on the distal portion 136a of the tubular member 136, near the distal end of the tubular member and near the distal opening 138 of the passageway 137. A conductive electrical lead 148 extends from the electrode through the tubular member 136, for example in any manner discussed above, to the proximal end of the catheter 146. Lead 148 is optionally a braid, which can optionally be referred to as a shield, formed from a suitable conductive metal. The exposed surface area of annular or ring electrode 147 is greater than the surface area of tip electrode 128 of the guidewire 127 to facilitate creation of spark 139 at the tip electrode when the electrodes 128, 147 are energized with radio frequency energy. Catheter 146 and ablation guidewire 127 can operate together to treat a lesion or blood vessel in the manner discussed above, and together can optionally be referred to as a treatment device or system 149 of the invention.

[0063] An optional embodiment of a delivery catheter 156 of the invention is shown in FIGS. 9-12. Catheter 156 includes an electrode, for example an annular electrode 157, provided on the outer surface of the tubular member 136. Electrode 157 is on the distal portion 136a of the tubular member 136, near the distal end of the tubular member and near the distal opening 138 of the passageway 137. A conductive electrical lead 158 extends from the electrode through the tubular member 136, for example in any manner discussed above, to the proximal end of the catheter 146. Lead 158 is optionally a braid or shield formed from a suitable conductive metal. The exposed surface area of annular or ring electrode 157 is greater than the surface area of tip electrode 128 of the guidewire 127 to facilitate creation of spark 139 at the tip electrode when the electrodes 128, 157 are energized with radio frequency energy. For example, the surface area of the tip electrode 128 relative to the surface area of the annular electrode 157 can optionally range from 1% to 30% or optionally less than 10%. Catheter 156 and ablation guidewire 127 can operate together to treat a lesion or blood vessel in the manner discussed above, and together can optionally be referred to as a treatment device or system 159 of the invention.

[0064] An optional embodiment of a single pole ablation guidewire 166 of the invention is shown in FIG. 10. Guidewire 166 is substantially identical to guidewire 127 and like referencenumerals have been used to identify like components of the guidewires 127 and 166. An electrical sensor 167 is provided on the elongate member 122, for example near or proximate distal tip 124, for facilitating a treatment procedure that utilizes tip electrode 128 of the guidewire 166. The electrical sensor 167 can be of any suitable purpose, for example for measuring characteristics of the lesion. The electrical sensor 167 can of any suitable type, including a pressure sensor, a flow sensor, a temperature sensor, a magnetic sensor, a sensor to measure impedance or any combination of the foregoing. The guidewire 166 is shown within catheter 156, although it is appreciated that the guidewire can be utilized with any other catheter including other catheters of the invention. Catheter 156 and ablation guidewire 166 can operate together to treat a lesion or blood vessel in the manner discussed above, and together can optionally be referred to as a treatment device or system 168 of the invention. The electrical sensor 167 can provide feedback, for example to a controller, an RF generator or both, to tune the radio frequency treatment of the lesion by device or system 168. It is appreciated that an electrical sensor, for example of the foregoing type, can be provided on any ablation guidewire, catheter or device or system of the invention for use in a treatment procedure.

[0065] An optional embodiment of a single pole ablation guidewire 176 of the invention is shown in FIG. 12. Guidewire 176 is substantially similar to guidewire 127 and like reference numerals have been used to identify like components of the guidewires 127 and 176. The catheter includes a single electrode 177 mounted on the distal portion 122a of elongate member 122. Electrode 177 is optionally mounted on distal tip 124 to the member 122, and extends forwardly, distally or beyond the distal tip 124. The electrode optionally has the approximate shape of a semi sphere, half sphere or half ball centered on longitudinal axis 123 of the elongate member 122. The electrode optionally has a shape or size that is slightly larger than a semi sphere, half sphere or half ball, which is centered on longitudinal axis 123 of the elongate member 122. The electrode can be made of any suitable conductive metal, including any of the conductive metals utilized for conventional RF or other electrodes. The rounded shape of the electrode ends at a planar surface 178 that is mounted on distal tip 124 at an approximate right angle to longitudinal axis 123. The guidewire 176 is shown within catheter 156, although it is appreciated that the guidewire can be utilized with any other catheter including other catheters of the invention. Catheter 156 and ablation guidewire 176 can operate together to treat a lesion or blood vessel in the manner discussed above, and together can optionally be referred to as atreatment device or system 179 of the invention. The shape of tip electrode 177 has its sharpest edges near the annular electrode 157 and away from the distal most tip of the tip electrode. Thus when the tip electrode 177 is energized, a spark is initiated behind its distal most tip and reduces the chances of the radio frequency ablation perforating the blood vessel.

[0066] An optional embodiment of a single pole ablation guidewire 186 of the invention is shown in FIGS. 13-14. Guidewire 186 is substantially similar to guidewire 127 and like reference numerals have been used to identify like components of the guidewires 127 and 186. The catheter includes a single electrode 187 mounted on the distal portion 122a of elongate member 122. Electrode 187 is optionally mounted on distal tip 124 to the member 122, and extends forwardly, distally or beyond the distal tip 124. The electrode optionally has the shape of a sphere or ball and is optionally formed from two rings or annuluses 188. The electrode can be made of any suitable conductive metal, including any of the conductive metals utilized for conventional RF or other electrodes. The annuluses are optionally disposed at a right angle to each other. The annuluses are optionally concentrically disposed on a point lying on the central longitudinal axis of the elongate member 122. Each annulus optionally extends in a plane, with the two planes extending at right angles to each other and intersecting on a line disposed on the central longitudinal axis of the elongate member 122. Each annulus has a central circular opening. It is appreciated that tip electrode 187 can optionally be formed from two solid disks, not shown, that have do not have a central opening 189. The guidewire 186 is shown within a catheter, for example catheter 146 or catheter 156, although it is appreciated that the guidewire can be utilized with any other catheter including other catheters of the invention. The catheter and ablation guidewire 186 can operate together to treat a lesion or blood vessel in the manner discussed above, and together can optionally be referred to as a treatment device or system 191 of the invention.

[0067] An optional embodiment of a bipolar ablation guidewire 196 of the invention is shown in FIG. 15. Guidewire 196 includes an elongate member 197 extending along a longitudinal axis 198 and having a proximal portion, not shown, and a distal portion 197a. The elongate member can be made from any suitable electrically-insulating material, for example a suitable polymer such as nylon, polyethylene, polyurethane, polyimide, polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK) and Pebax. The elongate member can have a diameter optionally ranging from 0.008 to 0.118 inches, optionally from 0.014 inches to 0.038 inches oroptionally smaller or larger as a function of the size and location of the vessel being treated. The distal portion is optionally less stiff than the proximal portion of the elongate member, a more flexible distal tip facilitating navigation of the ablation guidewire through the turns and obstructions of a vessel. The distal portion 197a, which can include a distal tip 199, is adapted for insertion into the blood vessel for travel to the lesion and the proximal portion is configured to control movement of the distal portion during travel in the blood vessel. At least one electrode is carried by the distal portion 197a, and optionally a plurality of electrodes are provided on the distal portion.

[0068] A first or distal tip electrode 201 is optionally provided on distal tip 199 and a second or proximal annular electrode is optionally provided on the distal portion spaced proximally of the distal tip 199 and tip electrode 201. The tip electrode 201 can be of any suitable type and shape, including any of the tip electrode designs disclosed herein. Tip electrode 210 can optionally be a loop, micro loop or ring electrode, like electrode 128 disclosed herein. The electrodes can each be made of any suitable conductive metal, including any of the conductive metals of conventional electrodes. The exposed surface area of annular electrode 202 is optionally greater than the exposed surface area of tip electrode 201, including for the reasons discussed above for creating or enhancing spark 203 generated by tip electrode 201. For example, the surface area of the tip electrode 201 relative to the surface area of the annular electrode 202 can optionally range from 1% to 30% or optionally less than 10%.

[0069] An electrically-insulated conductive lead is carried by the elongate member 197 for each electrode 201, 202 of guidewire 196 and is electrically coupled to the respective electrode. The leads can be of any suitable type, include a wire, a braid or shield, a helix and a hypotube. Each lead extends from the distal portion 197a to the proximal portion of the elongate member 197 and is adapted for coupling to a suitable radio frequency generator, like radio frequency generator 46, to cause radio frequency energy to be delivered to the respective electrode of the guidewire in any suitable manner, including as disclosed herein. The lead for tip electrode 201 is optionally a corewire 206, for example a conductive corewire extending along the central longitudinal axis of the guidewire, surrounded by a layer of electrically-insulating material 207. The lead for annular electrode 202 is optionally a conductive braid 208, which can optionally be called a shield, that extends annularly around corewire lead 206 and electrically-insulating layer 207. An exterior electrically-insulating layer 209 surrounds the conductive braid 208 along thelength of the guidewire 196. The construction of corewire lead 206, electrically-insulating layer 207, conductive braid 208 and exterior electrically-insulating layer 209 resemble the construction of a coaxial cable. Such a coaxial construction can contribute to improved current signal transmission, improved voltage signal transmission or both, providing less noise and more efficient signal transmission. Annular coils 211 extend around the electrically-insulating layer 207 and underlying corewire lead 206, and inside or beneath exterior electrically-insulating layer 209, between the tip electrode 201 and the annular electrode 202. The coils can be made from any suitable material, including stainless steel, and enhance the structure and safety of the ablation guidewire. In this regard, for example, the coils optionally provide structure and strength to the distal portion 197a, which can optionally hinder undesirable fracturing or bending of corewire lead 206. The coils optionally provide flexibility to the distal tip 199 of the ablation guidewire.

[0070] At least one of the electrodes 201, 202 is an active electrode, and optionally both of the electrodes are active electrodes. The RF generator can optionally be configured to selectively or alternatively deliver RF energy in any suitable pulsed manner to one of the electrodes, with the other electrode serving as the return electrode. The application of RF energy to the electrodes can optionally create the spark 203, which can optionally serve to disintegrate part of the lesion so as to create a space therein for further advancement or movement of the guidewire. Guidewire 196 can be utilized with any suitable delivery catheter, including any of the delivery catheters disclosed herein, and together can form a treatment device or system of the invention.

[0071] The treatment device of the invention can optionally include a treatment guidewire of any suitable type for treating a lesion in a blood vessel of a mammalian body, for example for treating a lesion with the aid of a balloon or other treatment catheter. A suitable ablation treatment guidewire 221 can include an elongate member 222 extending along a longitudinal axis 223 and having a proximal portion 222a and a distal portion 222b (see FIGS. 16-17). The elongate member can be made from any suitable electrically-insulating material, for example a suitable polymer such as nylon, polyethylene, polyurethane, polyimide, polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK) and Pebax. The elongate member can have a diameter optionally ranging from 0.008 to 0.118 inches, or optionally ranging from 0.014 inches to 0.038 inches. The distal portion 222b is optionally less stiff than the proximal portion 222a of theelongate member, a more flexible distal tip facilitating navigation of the ablation guidewire 196 through the turns and obstructions of a vessel. The distal portion 222b, which can include a distal tip 224, is adapted for insertion into the blood vessel for travel to the lesion and the proximal portion 222a is configured to control movement of the distal portion during travel in the blood vessel. Distal tip 224 can optionally be provided with a rounded, curved or blunt head 226 for facilitating travel of the guidewire through the blood vessel, including optionally through a lesion or occlusion for a treatment procedure thereof. Such head 226 can optionally be in the form of a ball 226 provided on the distal end of a shaft 227 that extends longitudinally into the distal portion 222b of the guidewire 221. The head 226 and shaft 227 can optionally be a unitary member, that is formed form a single piece of material. The shaft 227, and optionally the head 226, can be made from any suitable material, for example any suitable dielectric or other material.

[0072] At least one electrode is carried by the distal portion 222b. When the treatment guidewire of the invention is a bipolar treatment guidewire, first electrode 228 and a second electrode 229 are provided on the distal portion 222b. Each of the electrodes 228, 229 can optionally be annular electrodes provided or exposed on the outer surface of the elongate member 222. The exposed surface area of the electrodes 228, 229 can optionally be substantially equal. First electrode 228 can optionally be referred to as the distal electrode or the distal annular electrode. Second electrode 229 can optionally be referred to as the proximal electrode or the proximal annular electrode. The electrodes can each be made of any suitable conductive metal, including any of the conductive metals utilized for conventional RF or other electrodes. The electrodes 228, 229 can be spaced apart any suitable distance, optionally as function of the size and location of the lesion or occlusion to be treated. The electrodes 228, 229 can optionally be spaced apart a distance ranging from one to 40 millimeters.

[0073] An insulated conductive lead is carried by the elongate member 222 for each electrode 228, 229 of treatment guidewire 221 and is electrically coupled to the respective electrode. The leads can be of any suitable type, include a wire, a braid or shield, a helix and a hypotube. Each lead extends from the distal portion 222b to the proximal portion 222a of the elongate member 222 and is adapted for coupling through a connector 47 to a suitable radio frequency generator, controller or both, like radio frequency generator 46, to cause radio frequency energy to be delivered to the respective electrode of the guidewire. The lead for distalelectrode 228 is optionally a corewire 236, for example a conductive corewire extending along the central longitudinal axis of the guidewire, surrounded by a layer of insulating material 237. The lead for the proximal electrode 229 is optionally a conductive braid 238 extending annularly around corewire lead 236 and electrically-insulating layer 237. An exterior electrically- insulating layer 239 forms the outer layer of the guidewire 221 and surrounds the conductive braid 238, which can optionally be referred to as a shield, along the length of the guidewire 221 The construction of corewire lead 236, electrically-insulating layer 237, conductive braid 238 and exterior electrically-insulating layer 239 resemble the construction of a coaxial cable. A spring coil 241 is optionally included in distal tip 224 to enhance the flexibility of the distal tip. The spring coil can be made from any suitable material, including stainless steel.

[0074] At least one of the electrodes 228, 229 is an active electrode, and optionally both of the electrodes are active electrodes. The RF generator can optionally be configured to selectively or alternatively deliver RF energy in any suitable pulsed manner to one of the electrodes, including as disclosed herein, with the other electrode serving as the return electrode. The application of RF energy to the electrodes can optionally create a spark 242 between the electrodes, which can facilitate the treatment effect of any balloon or other treatment catheter utilized with the guidewire 221. Treatment guidewire 221 can be utilized with any suitable balloon or other treatment catheter, including any of the balloon or other treatment catheters disclosed herein, and together can form a treatment device or system of the invention.

[0075] A variety of treatment catheters can be used with treatment guidewire 221, or similar treat guidewires, to treat lesions or occlusions in a blood vessel. The treatment catheter, which can optionally be referred to as a microcatheter, can be formed from an elongate tubular member 251 made from any suitable electrically-insulating material, for example a suitable polymer such as nylon, polyethylene, polyurethane, polyimide, polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK) and Pebax. The tubular member 251 has a distal portion 25 la. The tubular member can be of an outer diameter suitable for introduction into and travel through a blood vessel of a patient, for example optionally ranging from 0.7 to 6.7 millimeters or optionally ranging from 0.7 to 4.0 millimeters. The tubular member 251 has an outer cylindrical surface 252 and an inner cylindrical surface 253 for forming an internal passageway 254, which can have an internal diameter optionally ranging from 0.008 to 0.118 inches or optionally ranging from 0.014 to 0.038 inches. Passageway 254 extends distally to a distal opening 256.The internal passageway 137 and the guidewire to be utilized with the catheter are appropriately sized so that the guidewire can slide longitudinally within the catheter. The tubular member extends along a longitudinal axis 257.

[0076] The catheter can optionally be provided with at least one conductive element, and is optionally provided with a plurality of conductive elements that are sized and longitudinally spaced apart along tubular member 251. The conductive elements optionally extend from the inner surface 253 to the exterior of the tubular member 251. The conductive elements optionally extend from the inner surface 253 to the outer surface 252 of the tubular member. The conductive elements are optionally each annular in shape. An annular conductive element can be a unitary member, for example formed from a single piece of material, or consist of a plurality of separate arcuate segments that together have the shape of an annulus. The conductive elements can be made of any suitable conductive metal, including any of the conductive metals of conventional electrodes. The conductive elements are optionally positioned and spaced on inner surface 253 of the tubular member 251 so as to register with the annular electrodes 228, 229 of treatment guidewire 221 when the guidewire is introduced into a desired position within the catheter.

[0077] An optional treatment catheter 261 of the invention is shown in FIGS. 18-20. The treatment catheter includes a plurality of conductive elements, for example two, four or six, of the type disclosed above. For example, a first or distal conductive element 262 and a second or proximal conductive element 263 are provided on the distal portion 251a of the elongate tubular member 251 of catheter 261. The number and longitudinal spacing of the conductive elements on a treatment catheter of the invention can optionally be a function of the size or length of the lesion or occlusion to be treated. The conductive elements 262, 263 are positioned and spaced on inner surface 253 of the tubular member 251 so as to electrically register respectively with the electrodes 228, 229 of treatment guidewire 221 when the guidewire is desirably positioned within the catheter, as shown in FIG. 18. Such electrical registration, which can optionally be referred to as electrical engagement, can be by any suitable means, for example a slidable slip or press fit between the conductive elements and the electrodes. The conductive elements can optionally extend radially inwardly from the inner surface 253 to facilitate their engagement with the electrodes of the treatment guidewire. Desired positioning of the conductive elements of the catheter relative to the electrodes of the guidewire can be indicated in any suitable manner. Forexample, impedance monitoring of the electrodes can optionally be used for obtaining such desired positioning. The conductive elements and electrodes, for example the inner surface of the conductive elements and the outer surface of the electrodes can optionally be provided with cooperatively engaging protuberances and recesses for indicating, obtaining or maintaining registration, or any combination of the foregoing. For example, each pair of a conductive element and electrode can be provided with an annular protuberance, ridge or rim and an annular recess for receiving or seating the protuberance, ridge or rim. Each of the electrodes 228, 229 of the guidewire 221 can optionally be provided with an annular protuberance, ridge or rim 266 and each of the conductive elements 262, 263 of the catheter 261 can optionally be provided with an annular recess 267 for receiving the protuberance of the respective electrode when the guidewire is properly positioned in the catheter so that the electrodes of the guidewire register, for example are centered, with the conductive elements of the catheter (see FIG. 19). Alternatively, each of the conductive elements 262, 263 of the catheter 261 can optionally be provided with an annular protuberance, ridge or rim 268 and each of the electrodes 228, 229 of the guidewire 221 can optionally be provided with an annular recess 269 for receiving the protuberance of the respective conductive element when the guidewire is properly positioned in the catheter so that the electrodes of the guidewire register with the conductive elements of the catheter (see FIG. 20).

[0078] Catheter 261 and ablation guidewire 221 can operate together to treat a lesion or occlusion in a blood vessel, and together can optionally be referred to as a treatment device or system 271 of the invention. In an optional procedure, catheter 261 is optionally centered on an occlusion or lesion in the blood vessel, for example by introduction over a suitable delivery guidewire or ablation guidewire of the invention. Guidewire 221 can optionally be introduced in the blood vessel through catheter 261. The rounded distal head 226 can facilitate pushing of the distal end of the guidewire into, through or past a lesion or occlusion. The flexible distal tip 199 can facilitate travel of the guidewire into, through or past a lesion of occlusion. Guidewire 221 is positioned in the catheter 261 so that the electrodes 228, 229 of the guidewire are registered with the conductive elements 262, 263 of the catheter. Such registration can be measured or determined by monitoring or measuring signals such as impedance in the vicinity of the electrodes. The RF generator can optionally be configured to measure impedance, and will likely see a change in impedance once there is direct contact between the electrodes and theconductive elements. RF energy supplied by the generator to the electrodes of the guidewire is provided to the conductive elements of the catheter to treat the lesion or occlusion in a desired manner. Such RF energy to the conductive elements can optionally create a spark between the conductive elements, which can create fissures in the lesion or occlusion to further enhance the treatment of the lesion or occlusion. A treatment can optionally include sequentially pairing electrodes 228, 229 of the guidewire with multiple pairs of conductive elements on the catheter, for example when more than two conductive elements are provided on the catheter.

[0079] An optional embodiment of a treatment catheter 276 of the invention is shown in FIG. 21 for use with treatment guidewire 221. Catheter 276 is substantially similar to catheter 261 and like reference numbers have been used to identify like components of catheters 261 and 276. The catheter 276 includes elongate tubular member 251. The catheter 276 further includes a distal conductive element 277 substantially similar to distal conductive element 262 of catheter 261 and a proximal conductive element 278 substantially similar to proximal conductive element 263 of catheter 261, but not necessarily including any registration protuberances 268 or recesses 267, for registering with respective electrodes 228, 229 of the guidewire 221. The conductive elements 277, 278 can optionally each be an annular conductive element, which can be a unitary member, for example formed from a single piece of material, or consist of a plurality of separate arcuate segments that together have the shape of an annulus. The treatment catheter 276, which can optionally be referred to as a balloon catheter, includes an inflatable balloon 281 on distal portion 251a of the elongate tubular member 251 overlying conductive elements 277, 278. An inflation lumen 282 is provided on the elongate tubular member 251, and extends to the proximal portion of the tubular member 251, for permitting inflation of the balloon 281 in situ when catheter 276 is properly positioned in a blood vessel for treatment. The length of the balloon, the number of conductive elements on catheter 276 or both can optionally be a function of the size or length of the lesion or occlusion being treated. For example, a longer lesion may optionally require a longer balloon, more than two conductive elements or both. For example, four or six conductive elements, not shown, within the balloon may be required for longer lesions. Balloon 281 can optionally be coated with any suitable drug or medicament, for example including antiproliferative drugs, the Limus family of drugs or paclitaxel.

[0080] Balloon catheter 276 and ablation guidewire 221 can operate together to treat a lesion or occlusion in a blood vessel, and together can optionally be referred to as a treatment device orsystem 282 of the invention. In an optional procedure, catheter 276 is optionally centered on an occlusion or lesion in the blood vessel, for example by introduction over a suitable delivery guidewire or ablation guidewire of the invention. Once guidewire 221 is positioned in the catheter 276 so that the electrodes 228, 229 of the guidewire are registered with the conductive elements 277, 278 of the catheter 276, balloon 281 can be inflated in the blood vessel or occlusion in the blood vessel to create fissures in the lesion or occlusion, expand the blood vessel or both. RF energy supplied to the electrodes of the guidewire 221 is provided to the conductive elements 278, 278 of the catheter 276 and can optionally create a spark 284 between the conductive elements, which can enhance the creation of fissures and enhance the expansion of the blood vessel by the balloon 281. Any such fissures can facilitate the effectiveness of any drug carried by the balloon 281. When more than two conductive elements are provided on catheter 276, a treatment can optionally include moving the guidewire 221 longitudinally within the catheter from a first treatment position, where the electrode 228, 229 of the guidewire register with one pair of conductive elements on the catheter, to a second treatment position, where the electrodes 228, 229 register with another pair of conductive elements on the catheter. A conductive element of the treatment catheter can optionally be included in both the one pair of conductive element of the first treatment position and the another pair of conductive elements of the second treatment position.

[0081] An optional embodiment of a treatment catheter 291 of the invention is shown in FIG. 22 for use with treatment guidewire 221. Catheter 276 is substantially similar to catheters 261 and 276 and like reference numbers have been used to identify like components of catheters 261, 276 and 291. The catheter 291 includes elongate tubular member 251. The catheter 291 can further include distal conductive element 277 and proximal conductive element 278 for registering with respective electrodes 228, 229 of the guidewire 221. The treatment catheter 291, which can optionally be referred to as a drug eluting balloon catheter, includes inflatable balloon 281 on distal portion 251a of the elongate tubular member 251 overlying conductive elements 277, 278. The balloon 281 can contain any suitable treatment drug or medicament, for example including anti-proliferative drugs, the Limus family of drugs and paclitaxel. The tubular member 251 of the balloon catheter 291 is optionally provided with a passageway, not shown, extending from the proximal portion of the tubular member to an opening inside the inflatable balloon 281 for delivering a drug to the balloon. Balloon 281 optionally includes a perforated surface 294,for example formed with a plurality of micropores 295, extending around the periphery of the balloon for permitting distribution of the medicament to the lesion, occlusion or other area of treatment in a blood vessel upon inflation of the balloon 281. The inflation lumen 282 provided on the elongate tubular member 251 permits the inflation of the balloon 281 in situ when catheter 291 is properly positioned in a blood vessel for treatment.

[0082] Drug eluting balloon catheter 291 and ablation guidewire 221 can operate together to treat a lesion or occlusion in a blood vessel, for example in any procedure disclosed herein, and together can optionally be referred to as a treatment device or system 296 of the invention. In an optional procedure, catheter 291 is optionally centered on an occlusion or lesion in the blood vessel, for example by introduction over a suitable delivery guidewire or ablation guidewire of the invention. Once guidewire 221 is positioned in the catheter 291 so that the electrodes 228, 229 of the guidewire are registered with the conductive elements 277, 278 of the catheter 291, balloon 281 can be inflated in the blood vessel or occlusion in the blood vessel to create fissures in the lesion or occlusion, expand the blood vessel or both. The inflation of balloon 281 causes the delivery of the medicament in the balloon through the micropores 295 of the perforated surface of the balloon to the lesion or occlusion. RF energy supplied to the electrodes of the guidewire 221 is provided to the conductive elements 277, 278 of the catheter 291 and can optionally create a spark 297 between the conductive elements, which can enhance the creation of fissures in the lesion or occlusion and enhance the expansion of the blood vessel by the balloon 281 and the penetration of the medicament into the lesion or occlusion. The presence of the drug or medicament in the balloon 281 during introduction of catheter 291 through the blood vessel to the treatment site reduces undesirable washout or dissipation of the drug or medicament during such introduction and prior to the delivery of the drug or medicament to the lesion or occlusion.

[0083] An optional embodiment of a treatment catheter 301 of the invention is shown in FIG. 23 for use with treatment guidewire 221. Catheter 301 is substantially similar to catheters 261 and 276 and like reference numbers have been used to identify like components of catheters 261,276 and 301. The catheter 301 includes elongate tubular member 251, distal conductive element277 for registering with distal electrode 228 of the guidewire 221 and proximal conductive element 278 for registering with proximal electrode 229 of the guidewire 221. The treatment catheter 301, which can optionally be referred to as a drug eluting balloon catheter, includesinflatable balloon 281 on distal portion 251a of the elongate tubular member 251 overlying conductive elements 277, 278. The balloon 281 can contain any suitable treatment drug or medicament 302, for example including anti-proliferative drugs, the Limus family of drugs and paclitaxel. The drug or medicament can be carried by the balloon in any suitable manner, for example suitable linkers 303 provided on at least a portion of the outer surface of the balloon for releasably securing the drug or medicament to the balloon. Examples of suitable linkers include polyethylene glycol linkers, chemi cal -activated linkers, light-activated linkers, thermal-activated linkers, magnetic field-activated linkers, pressure-activated linkers and any combination of the foregoing. The inflation lumen 282 provided on the elongate tubular member 251 permits the inflation of the balloon 281 in situ when catheter 301 is properly positioned in a blood vessel for treatment.

[0084] Drug eluting balloon catheter 301 and ablation guidewire 221 can operate together to treat a lesion or occlusion in a blood vessel, for example in any procedure disclosed herein, and together can optionally be referred to as a treatment device or system 304 of the invention. In an optional procedure, catheter 301 is optionally centered on an occlusion or lesion in the blood vessel, for example by introduction over a suitable delivery guidewire or ablation guidewire of the invention. Once guidewire 221 is positioned in the catheter 301 so that the electrodes 228, 229 of the guidewire are registered with the conductive elements 277, 278 of the catheter 301, balloon 281 can be inflated in the blood vessel or occlusion in the blood vessel to create fissures in the lesion or occlusion, expand the blood vessel or both. The inflation of the balloon causes the delivery of the medicament 302 in the balloon to the lesion or occlusion. The linkers 303 can be activated or triggered to release the medicament 302 by any suitable controllable event, including for example the generation of pressure waves, heat, a magnetic field, a chemical reaction, light within the inflatable balloon 281 or any combination of the foregoing by any suitable means. RF energy supplied to the electrodes of the guidewire 221 is provided to the conductive elements 277, 278 of the catheter 301 and can create a spark 306 between the conductive elements, which can enhance the creation of fissures and enhance the expansion of the blood vessel by the balloon 281 and the penetration of the medicament 302 into the lesion or occlusion. In one example, light-activated linkers specific to a particular wavelength of light can be utilized and then that particular wavelength of light can be generated within the balloon, for example via the guidewire electrodes, in order to release the drug or medicament in the body.The securing of the drug or medicament to the balloon 281, for example by linkers 303, during introduction of catheter 301 through the blood vessel to the treatment site reduces undesirable washout or dissipation of the drug or medicament during such introduction and prior to the delivery of the drug or medicament to the lesion or occlusion.

[0085] An optional embodiment of a treatment catheter 311 of the invention is shown in FIG. 24 for use with treatment guidewire 221. Catheter 311 is substantially similar to catheters 261 and 276 and like reference numbers have been used to identify like components of catheters 261,276 and 311. The catheter 311 includes elongate tubular member 251, distal conductive element277 for registering with distal electrode 228 of the guidewire 221 and proximal conductive element 278 for registering with proximal electrode 229 of the guidewire 221. The treatment catheter 311, which can optionally be referred to as a drug eluting balloon catheter, includes inflatable balloon 281 on distal portion 251a of the elongate tubular member 251 overlying conductive elements 277, 278. The inflation lumen 282 provided on the elongate tubular member 251 permits the inflation of the balloon 281 in situ when catheter 301 is properly positioned in a blood vessel for treatment. The treatment catheter 311 can optionally include an additional inflatable balloon 312 on distal portion 251a of the elongate tubular member 251. The additional balloon overlies balloon 281, for example surrounds the balloon 281. The additional balloon 312 can optionally be referred to as an outer or exterior balloon. Balloon 281 can optionally be referred to as an inner or interior balloon. Any suitable drug or medicament, for example including anti-proliferative drugs, the Limus family of drugs or paclitaxel, can be provided in the additional balloon 312. Balloon 281 can optionally be coated with the drug or medicament for providing the drug or medicament within balloon 312. An additional inflation lumen 313 can optionally be provided on the elongate tubular member 251 and extend to the proximal portion of the tubular member 251 for permitting a drug or medicament to be supplied to the addition balloon 312. The additional balloon 312 optionally includes a perforated surface 314, for example formed with a plurality of micropores 316, extending around the periphery of the balloon for permitting distribution of the medicament to the lesion, occlusion or other area of treatment in a blood vessel upon inflation of the balloon 312.

[0086] Balloon catheter 311 and ablation guidewire 221 can operate together to treat a lesion or occlusion in a blood vessel, for example in any procedure disclosed herein, and together can optionally be referred to as a treatment device or system 317 of the invention. In an optionalprocedure, catheter 31 1 is optionally centered on an occlusion or lesion in the blood vessel, for example by introduction over a suitable delivery guidewire or ablation guidewire of the invention. Once guidewire 221 is positioned in the catheter 311 so that the electrodes 228, 229 of the guidewire are registered with the conductive elements 277, 278 of the catheter 311, the interior balloon 281 can be inflated in the blood vessel or occlusion in the blood vessel, which can create fissures in the lesion or occlusion, expand the blood vessel or both. The inflation of the interior balloon 281 causes the delivery of the drug or medicament in the additional balloon to the lesion or occlusion or any combination of the foregoing. RF energy supplied to the electrodes of the guidewire 221 is provided to the conductive elements 277, 278 of the catheter 301 and can create a spark 318 between the conductive elements, which can enhance the creation of fissures, enhance the expansion of the blood vessel by the balloons 281, 312, enhance the penetration of the medicament into the lesion or occlusion or any combination of the foregoing. The presence of the drug or medicament in the additional balloon 312 during introduction of catheter 311 through the blood vessel to the treatment site reduces undesirable washout or dissipation of the drug or medicament during such introduction and prior to the delivery of the drug or medicament to the lesion or occlusion.

[0087] The electrical registration or engagement between the conductive elements of the treatment catheter of the invention and the treatment guidewire of the invention can be by any suitable means, including any of the means discussed above. Such electrical registration or engagement can optionally include radial movement of the conductive elements relative to the tubular member of the catheter into contact with the electrodes of the guidewire, for example caused by inflation of the balloon of the treatment catheter. An optional embodiment of a treatment catheter of the invention having such radially movable conductive elements is shown in FIGS. 25-26, it being appreciated that such radially movable conductive elements can be incorporated into any of the balloon catheters of the invention, including catheters 276, 291, 301 and 311. Treatment catheter 326 is for use with treatment guidewire 221. Catheter 326 is substantially similar to catheters 261, 276, 291, 301 and 326 and like reference numbers have been used to identify like components of catheters 261, 276, 291, 301 and 326. The catheter 326 includes elongate tubular member 251, distal conductive element 327 for registering with distal electrode 228 of the guidewire 221 and proximal conductive element 328 for registering with proximal electrode 229 of the guidewire 221. The conductive elements 327, 328 can optionallyeach be an annular conductive element, for example formed a plurality of separate arcuate segments that together have the shape of an annulus. The conductive elements can be made from any suitable conductive metal, including any of the conductive metals utilized for conventional RF or other electrodes. The treatment catheter 326, which can optionally be referred to as a balloon catheter, includes inflatable balloon 281 on distal portion 251a of the elongate tubular member 251 overlying conductive elements 327, 328. The inflation lumen 282 provided on the elongate tubular member 251 permits the inflation of the balloon 281 in situ when catheter 301 is properly positioned in a blood vessel for treatment.

[0088] Each of the conductive elements 327, 328 is movable radially outwardly and radially inwardly in the tubular wall of tubular member defined by outer surface 252 and inner surface 253. Each conductive element is formed with an enlarged outer portion or flange 331, an enlarged inner portion or flange 332 and a central portion 333 that is narrower than the outer and inner flanges 331, 332. Each of the outer flange 331 and inner flange 332 has a transverse, cross or longitudinal dimension that is larger than the transverse, cross or longitudinal dimension of the central portion 333. The central portion 333 of each conductive element moves radially inwardly and outwardly in a respective opening 336, which can optionally be referred to as a radial opening, provided in the tubular wall of member 251. The inward radial movement of the central portion 333 in opening 336 is limited or stopped by the engagement of the inner flange 332 with the respective electrode of the guidewire, as shown in FIG. 26 where balloon 281 is inflated and the conductive elements are in their inward position. The outward radial movement of the central portion 333, and thus conductive element, in opening 336 is limited or stopped by the engagement of the inner flange 332 with the inner surface 253 of the tubular member 251, as shown in FIG. 25 where the balloon 281 is uninflated and conductive elements are in their outward position. The outer and inner flanges 331, 332 retain the conductive element within the respective radial opening 336 of the catheter 311. A spring or other suitable element, not shown, can be provided in each conductive element for urging it towards its outward position, illustrated in FIG. 25, for facilitating positioning of the conductive element over the respective electrode of the guidewire 221 during placement of the guidewire in catheter 326.

[0089] Balloon catheter 326 and ablation guidewire 221 can operate together to treat a lesion or occlusion in a blood vessel, for example in any procedure disclosed herein, and together can optionally be referred to as a treatment device or system 337 of the invention. In an optionalprocedure, catheter 326 is optionally centered on an occlusion or lesion in the blood vessel, for example by introduction over a suitable delivery guidewire or ablation guidewire of the invention. Once guidewire 221 is positioned in the catheter 331 so that the electrodes 228, 229 of the guidewire are registered longitudinally with the conductive elements 327, 328 of the catheter 326, the interior balloon 281 can be inflated in the blood vessel or occlusion in the blood vessel, which can create fissures in the lesion or occlusion, expand the blood vessel or both. The pressurization of the balloon 281 for inflation urges each of the conductive elements 327, 328 radially inwardly within their respective opening 336 in the tubular member 251 of the catheter 326 until the inner flange 332 of each conductive element engages the respective electrode of the guidewire 221. Other means can be provided to move the conductive elements 327, 328 radially inward, radially outward or both. For example, magnetic fields can be utilized to move the conductive elements. A magnetic field can optionally be created by the guidewire, which in turn can urge the conductive elements 328, 328 inwardly or outwardly based on the polarity created by the guidewire. A balloon catheter of the invention that includes the movable conductive elements 327, 328 of catheter 326 can be utilized with guidewire 221 or any other suitable treatment guidewire of the invention in any of the treatment procedures disclosed herein.

[0090] Any treatment balloon catheter can be provided with at least one protruding element overlying the inflatable balloon, the at least one protruding element having an outer edge, for example a longitudinally-extending outer edge, for scoring a lesion or occlusion in a blood vessel upon inflation of the inflatable balloon. The catheter can optionally include a plurality of protruding elements overlying or extending around the balloon, for example circumferentially spaced-apart around the balloon at any suitable angle including 20°, 40°, 60°, 90° or 120°. An optional treatment catheter 346 having at least one protruding element of the invention is shown in FIGS. 27-31. Catheter 346 can be used with any suitable guidewire, including any treatment guidewire of the invention. An optional guidewire 347, shown in in FIG. 27, is formed from an elongate member 348 having a distal portion 348a and a distal tip 349. The elongate member 348 can be of any suitable type, for example elongate member 197 disclosed herein, and can optionally include at least one ablation electrode. The guidewire 347 is a single pole treatment guidewire and has a first or distal electrode 351 optionally provided on distal tip 349. The tip electrode 351 can be of any suitable type and shape, including any of the tip electrode designs disclosed herein. For example, the tip electrode 351 can optionally be a loop, micro loop or ringelectrode, like electrode 128 disclosed herein. The electrode 351 can be made of any suitable conductive metal, including any of the conductive metals of conventional electrodes. An insulated conductive lead 352 is carried by the elongate member 348 and is electrically connected at its distal end to the tip electrode. The lead 352 can be of any suitable type, including a wire, a braid, a helix and a hypotube. The lead 352 extends from the distal portion 348a to the proximal portion of the elongate member 348 and is adapted for coupling to a suitable radio frequency generator, like radio frequency generator 46, to cause radio frequency energy to be delivered to the tip electrode 351 in any suitable manner, including as disclosed herein. The lead 352 is optionally a corewire 206, for example a conductive corewire extending along the central longitudinal axis of the guidewire, and is surrounded by a layer of insulating material 353 of the elongate member 343 (see FIG. 31). The layer of insulating material 353 can optionally be referred to as an insulating jacket.

[0091] The treatment catheter 346 can be of any suitable type, including any treatment catheter having an expandable member at its distal portion for expanding or otherwise treating a portion of a blood vessel. The treatment catheter can include any of the balloon catheters disclosed herein and any balloon catheter including any or all of the features included in the balloon catheters disclosed herein. Optional catheter 346 can be formed from an elongate tubular member 356 made from any suitable electrically-insulating material, for example a suitable polymer such as nylon, polyethylene, polyurethane, polyimide, polytetrafluoroethylene (PTFE), poly etheretherketone (PEEK) and Pebax. The tubular member 356, which can optionally be like tubular member 251, has a distal portion 356a. The tubular member can be of an outer diameter suitable for introduction into and travel through a blood vessel of a patient, for example optionally ranging from 0.7 to 6.7 millimeters or optionally ranging from 0.7 to 4.0 millimeters. The tubular member 356 has an outer cylindrical surface 357 and an inner cylindrical surface 358 for forming an internal passageway 359, which can have an internal diameter optionally ranging from 0.008 to 0.118 inches or optionally ranging from 0.014 to 0.038 inches. Passageway 359 extends distally to a distal opening 361. The internal passageway and the guidewire to be utilized with the catheter are appropriately sized so that the guidewire can slide longitudinally within the catheter. The tubular member extends along a longitudinal axis 362. The catheter 346 includes a suitable expandable member, for example an inflatable balloon 363, on distal portion 356a of the elongate tubular member 356. A suitable inflationlumen 364 is provided on the elongate tubular member 356 to permit inflation of the balloon 363 in situ when catheter 346 is properly positioned in a blood vessel for treatment (see FIG. 31).

[0092] Catheter 346, which can optionally be referred to as a balloon catheter, is provided with at least one protruding element 366 overlying the inflatable balloon 363. The at least one protruding element has an outer edge 367, for example a longitudinally -extending outer edge, for scoring a lesion or occlusion in a blood vessel upon inflation of the balloon 363. Catheter 346 can optionally include a plurality of protruding elements overlying or extending around the balloon 363, for example circumferentially spaced-apart around the balloon 363 at any suitable separation angle including 50°, 90° or 120°. Catheter 346 has three protruding elements 366 circumferentially spaced-apart around the balloon 363 at a separation angle of 120°. For simplicity, only a single protruding element 366 is shown in schematic catheter 346 illustrated in FIG. 27. Each protruding element 367 optionally extends longitudinally along the balloon 363 in a direction parallel to longitudinal axis 363, and can be secured to the catheter 346 in any suitable manner. Each protruding element can optionally be adhered to the outside or outer surface of the balloon 363. Each protruding element 367 can optionally overlie the balloon 363 with its opposite ends secured to the tubular member 356 of the catheter, for example by a first connector 368 extending proximally from the proximal end of the protruding element to the tubular member and a second connector 369 extending distally from the distal end of the protruding element to the tubular member. The connectors optionally follow the contour of balloon. Each protruding element 366 can optionally have a planar base surface 371 which overlies or is secured to the balloon, and can optionally taper inwardly as it extends radially outwardly from the tubular member 356 and axis 362 to its outer edge 367. (see FIGS. 28-30) Each protruding element can optionally have a triangular or substantially triangular cross- sectional shape, which includes base surface 371. A tapered surface 372 optionally extends from each side of the planar base surface 371 to the outer edge 367 (see FIGS. 28-30). Each protruding element 366 is optionally wedge shaped, for example from base surface 371 to its outer edge 367. The outer edge 367, which can optionally be called the scoring edge or end of the protruding element, can optionally be relatively pointed or narrow in width for facilitating scoring of the lesion or occlusion by the protruding element. Each protruding element 366 can be made from any suitable material such as any suitable polymer such as nylon or polyimide or any suitable metal such as stainless steel or nitinol. Each protruding element of the invention canoptionally have a circular cross-sectional shape, not shown. Each protruding element can optionally be formed from a wire, wire or cable capable of scoring or piercing a lesion when pressed against the lesion.

[0093] Each protruding element 366 can optionally have at least one electrode 373 for emitting radio frequency energy. The electrode can optionally be referred to as a protruding element electrode. The at least one electrode 373 can optionally be near or in the vicinity of the outer edge 367 of the protruding element. The at least one electrode 373 can optionally have an exposed portion near or at the outer edge 367 of the protruding element. Each protruding element 366 optionally has a single electrode 373 (see FIG. 27). The electrode 373 can have a portion exposed at the outer edge 367 (see FIG 29). The electrode 373 can optionally taper inwardly as it extends radially outwardly to the outer edge 367, and can optionally form part of the outer edge (see FIG. 29). Alternatively, the electrode 373 can be in the vicinity of the outer edge, have portion exposed at the outer edge and be recessed below the outer edge (see FIG. 30). An insulated conductive lead 376 is carried by the elongate tubular member 356 of the catheter 346 and is electrically connected at its distal end to the electrode 373 of the protruding element 366. The lead 376 can be of any suitable type, including a wire, a braid or shield, a helix and a hypotube. The lead 376 is optionally a conductive wire surrounded by a layer of insulating material 377, which can optionally be referred to as an insulating jacket. The lead 376 optionally extends from the electrode 373 through the protruding element 366 and then along the exterior of the tubular member to the proximal portion of the tubular member 356 and is adapted for coupling to a suitable radio frequency generator, like radio frequency generator 46, to cause radio frequency energy to be delivered to the electrode 373. The conductive lead 376 and insulating jacket 377 for the electrodes of each of the three protruding elements 366 of catheter 346 are shown in FIG. 31.

[0094] One or more of the protruding elements 366 can optionally be coated with any suitable drug or medicament, for example including anti-proliferative drugs, the Limus family of drugs or paclitaxel.

[0095] The tip electrode 351 of guidewire 347 can optionally pair with the electrode 373 of the protruding element 366 of balloon catheter 346 to form a bipolar pair of ablation electrodes. At least one of the tip electrode of the electrode of the protruding element is an active electrode, and optionally both of the electrodes are active electrodes. The RF generator can optionally beconfigured to selectively or alternatively deliver RF energy in any suitable pulsed manner to one of the electrodes, with the other electrode serving as the return electrode. The surface area of tip electrode 351 can optionally be greater than the surface area of protruding element electrode 366 to enhance the creation of a spark at the protruding element electrode 366 during an RF treatment procedure of a lesion or occlusion in a blood vessel.

[0096] Balloon catheter 346 and treatment guidewire 347 can operate together to treat a lesion or occlusion in a blood vessel, for example in any procedure disclosed herein, and together can optionally be referred to as a treatment device or system 378 of the invention. In an optional procedure, catheter 346 is optionally centered on an occlusion or lesion in the blood vessel, for example by introduction over a suitable delivery guidewire or ablation guidewire of the invention. Once guidewire 347 is desirably positioned in the catheter 346, the balloon 363 can be inflated in the blood vessel or occlusion in the blood vessel, which can create fissures in the lesion or occlusion, expand the blood vessel or both. The pressurization of the balloon 363 urges each protruding element 366, including the outer edge 367 of a protruding element, radially outwardly to engage and score the lesion or occlusion. Any drug or medicament carried by a protruding element can be delivered to the lesion or occlusion, whether indirectly by the protruding element being near the lesion or occlusion, directly by the protruding element engaging the lesion or occlusion or both. RF energy supplied to the electrodes 351, 373 can enhance the creation of fissures, enhance the scoring of the lesion or occlusion, enhance the expansion of the blood vessel by the balloon 363, enhance the penetration or effectiveness of the drug or medicament delivered by the one or more protruding ' elements or any combination of the foregoing, possibly by the creation of a spark between the electrodes or at electrode 373.

[0097] The protruding elements of any treatment balloon catheter of the invention can optionally be provided with a plurality of electrodes, for example a plurality of electrodes longitudinally spaced apart along the length of the protruding elements. The plurality of electrodes can optionally be longitudinally spaced apart along the outer edge of each protruding element. An optional treatment balloon catheter of the invention having one or more protruding elements with multiple electrodes is shown in FIG. 32. Catheter 386 therein is shown in use with any suitable guidewire, including any suitable guide of the invention such as guidewire 347 having tip electrode 351. Catheter 386 is substantially similar to catheter 346 and like reference numbers have been used to identify like components of catheters 386 and 346. Catheter 386includes elongate tubular member 356 having a distal portion 356a and outer and inner surfaces 357, 358. The inner surface 358 forms internal passageway 359 extending the length of the tubular member and terminating at a distal opening 361. An inflatable balloon 363 is provided on the distal portion 356a of the tubular member 356. At least one and optionally a plurality of circumferentially spaced-apart protruding elements 387 are carried by distal portion 356a, although only a single protruding element 387 is shown in FIG. 32 for simplicity. The protruding elements 387 can be substantially identical to the protruding elements 366 of catheter 346, except for the multiple electrodes on the protruding elements 387 of catheter 386, and like reference numerals have been used to identify like elements of protruding elements 387, 366. The plurality of electrodes of protruding element 387 can optionally be in the form of first or distal electrode 388 and second or proximal electrode 389 that is longitudinally spaced from the distal electrode 387. Each electrode 388, 389 is disposed at or near the outer edge 367 of the protruding element, and can each be like any of the electrodes 373 of catheter 346. An insulated conductive lead 391, which can be like any of the leads 376 of catheter 346, is carried by the elongate tubular member 356 of the catheter 386 for each of the electrodes 388, 389 and is electrically connected at its distal end to the respective electrode and can optionally extend from the electrode through the protruding element 387 and then along the exterior of the tubular member 356 to the proximal portion of the tubular member 356. The conductive leads 391 extending along the tubular member can be bundled together, for example in any conventional manner. Each conductive lead 391 is adapted for coupling to a suitable radio frequency generator, like radio frequency generator 46, to cause radio frequency energy to be delivered to the electrode in any suitable manner, including as disclosed herein.

[0098] The electrodes 388, 389 of each protruding element of catheter 386 can optionally pair with each other, with tip electrode 351 of guidewire 347, with the electrodes 388, 389 of another protruding element or any combination of the foregoing to form a bipolar pair of ablation electrodes. At least one of an electrode pair is an active electrode, and optionally both of the electrodes of a pair are active electrodes. The RF generator can optionally be configured to selectively or alternatively deliver RF energy in any suitable pulsed manner to either electrode of a pair, including as disclosed herein, with the other electrode of the pair serving as the return electrode.

[0099] Balloon catheter 386 and treatment guidewire 347 can operate together to treat a lesion or occlusion in a blood vessel, for example in any procedure disclosed herein, and together can optionally be referred to as a treatment device or system 392 of the invention. In an optional procedure, catheter 386 is optionally centered on an occlusion or lesion in the blood vessel, for example by introduction over a suitable delivery guidewire or ablation guidewire of the invention. Once guidewire 347 is desirably positioned in the catheter 386, the balloon 363 can be inflated in the blood vessel or occlusion in the blood vessel, which can create fissures in the lesion or occlusion, expand the blood vessel or both. The pressurization of the balloon 363 urges the outer edge 367 of each protruding element 387 radially outwardly to engage and score the lesion or occlusion. RF energy supplied to the electrodes 351, 388, 389, for example to any pair of electrodes including sequential pairs of electrodes, can enhance the creation of fissures, enhance the scoring of the lesion or occlusion, enhance the expansion of the blood vessel by the balloon 363 or any combination of the foregoing, possibly by the creation of a spark between the electrodes. An example spark 393 is shown in FIG. 32 between the distal and proximal electrodes 388, 389 paired in a bipolar configuration.

[0100] An optional treatment balloon catheter of the invention having one or more protruding elements with multiple electrodes in shown in FIG. 33. Catheter 401 therein is shown in use with any suitable guidewire, including any suitable guide of the invention such as guidewire 347 having tip electrode 351. Catheter 401 is substantially similar to catheter 346 and like reference numbers have been used to identify like components of catheters 401 and 346. Catheter 401 includes elongate tubular member 356 having a distal portion 356a and outer and inner surfaces 357, 358. The inner surface 358 forms internal passageway 359 extending the length of the tubular member and terminating at a distal opening 361. An inflatable balloon 363 is provided on the distal portion 356a of the tubular member 356. For simplicity, only one half of the balloon 363 is shown in FIG. 33. At least one and optionally a plurality of circumferentially spaced-apart protruding elements 402 are carried by distal portion 356a, for example as disclosed above, although only a single protruding element 402 is shown in FIG. 32 for simplicity. The protruding elements 402 can be substantially identical to the protruding elements 366 of catheter 346 and like reference numerals have been used to identify like elements of protruding elements 402, 366. At least one recess, and optionally more than one or a plurality of recesses, can be formed in the protruding element 402 and communicate with theouter edge 367 of the protruding element. Such a distal recess 403 and a proximal recess 404 can optionally be provided in the protruding element 402. Each protruding element of the catheter 401 is configured to selectively receive an insulated conductive lead with an exposed distal end, not shown, in the recesses 403, 404 of the protruding element. An optional insulated lead can include an electrically conductive wire with a layer of insulating material, which can optionally be called an insulating jacket, disposed around it but exposing the distal end of the wire. The insulated lead, which can optionally be called a movable lead, extends to the proximal end of the elongate tubular member 356 and is adapted for coupling to a suitable radio frequency generator, like radio frequency generator 46, to cause radio frequency energy to be delivered to the selected recess 403, 404 by the exposed end of the lead. The protruding element 402 is optionally provided with a bore 406, for example extending from the proximal end of the protruding element, that communicates with each of the recesses 403, 404. An optional conduit 407 can extend from the proximal end of the protruding element along the exterior of the tubular member 356 to the proximal end of the catheter 401. The movable lead can be slidably disposed in the conduit 407 and bore 406, with the exposed end of the movable lead provided in either the distal recess 403 or the proximal recess 404 for providing a selectively placed electrode in the protruding element.

[0101] The electrode of each protruding element 401 of catheter 401 can optionally pair with each other, with tip electrode 351 of guidewire 347, with the electrode of another protruding element or any combination of the foregoing to form a bipolar pair of ablation electrodes. At least one of an electrode pair is an active electrode, and optionally both of the electrodes of a pair are active electrodes. The RF generator can optionally be configured to selectively or alternatively deliver RF energy in any suitable pulsed manner to either electrode of a pair, with the other electrode of the pair serving as the return electrode. The surface area of the tip electrode 351 is optionally greater than the surface area of the exposed area of the movable lead, which can contribute to the formation of a spark in the vicinity of the exposed area of the movable lead located in a recess 403, 404 of a protruding element 402.

[0102] Balloon catheter 401 and treatment guidewire 347 can operate together to treat a lesion or occlusion in a blood vessel, for example in any procedure disclosed herein, and together can optionally be referred to as a treatment device or system 408 of the invention. In an optional procedure, catheter 401 is optionally centered on an occlusion or lesion in the blood vessel, forexample by introduction over a suitable delivery guidewire or ablation guidewire of the invention. Once guidewire 347 is desirably positioned in the catheter 401, the balloon 363 can be inflated in the blood vessel or occlusion in the blood vessel, which can create fissures in the lesion or occlusion, expand the blood vessel or both. The pressurization of the balloon 363 urges the outer edge 367 of each protruding element 402 radially outwardly to engage and score the lesion or occlusion. The exposed end of the movable lead, through slidable control of the movable lead at the proximal end of the balloon catheter 401, can be selectively disposed in either the distal recess 403 or the proximal recess 404 of the protruding element. RF energy supplied to the tip electrode 351, the selected electrodes of the protruding elements or both can form a bipolar pair of ablation electrodes, for example to any pair of electrodes including sequential pairs of electrodes, which can enhance the creation of fissures, enhance the scoring of the lesion or occlusion, enhance the expansion of the blood vessel by the balloon 363 or any combination of the foregoing, possibly by the creation of a spark between the selected electrodes.

[0103] A treatment catheter having a plurality of circumferentially spaced-apart protruding elements for use with any balloon catheter, for example any balloon catheter of the invention, can be provided. Optional catheter 416, illustrated in FIG. 34, can be formed from an elongate tubular member 417 made from any suitable electrically-insulating material, for example a suitable polymer such as nylon, polyethylene, polyurethane, polyimide, polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK) and Pebax. The tubular member has a proximal portion, not shown, and a distal portion 417a. The tubular member 417 has an internal passageway 418 extending the length of the tubular member that is adapted for introducing the tubular member into a blood vessel over the balloon catheter with which treatment catheter 416 is being utilized. The internal passageway is diametrically sized to be slidable over such balloon catheter. The tubular member 417 can be of any suitable outer diameter, for example optionally ranging from 1.7 to 9.0 millimeters, and the passageway 418 can have any suitable internal diameter, for example optionally ranging from one to seven millimeters. The tubular member 417 has an outer cylindrical surface and an inner cylindrical surface that forms the internal passageway 418. The catheter 416 can have any suitable length, for example as a function of the balloon catheter for which catheter 416 will be utilized. The catheter can optionally have a length ranging from 40 to 220 centimeters. Passageway 418 extends distally to a distal opening 423. The tubular member extends along a longitudinal axis 424.

[0104] The treatment catheter 416 has any suitable expandable structure 426 carried by the distal portion 417a of the tubular member 417 which can be slidably disposed over, or slidably receive, the distal balloon of the balloon catheter with which the catheter 416 is to be utilized. A plurality of protruding elements 427 are mounted on the expandable structure in circumferentially spaced-apart positions at any suitable separation angle, for example any of the separation angles for protruding elements disclosed herein. A plurality of three protruding elements 427 can optionally be provided, and adjacent protruding elements of such plurality of three can optionally be circumferentially spaced apart at a separation angle of 120°. The expandable structure 426 can optionally be an expandable cage structure of any suitable type. An optional cage structure includes a plurality of longitudinally-extending elements or members 428, for example strips, which are optionally equal in number to the number of protruding elements 427 of the catheter 416. The longitudinal members 428 can each have a proximal end portion 428a coupled or secured to distal portion 417a of the tubular member, a distal end portion 428b coupled together in any suitable member and a central portion 428c for carrying a protruding element 427. A protruding element 427, for example the planar base surface 371 of the protruding element, is secured by any suitable manner to the central portion 428c of each longitudinal member. The longitudinal members 428 can optionally be made from any material that is flexible, elastic or both. Each longitudinal member can optionally be made from a flexible plastic, stainless steel, a shape memory alloy or a superelastic shape memory alloy. A plurality of rings structures 429 of any suitable type can optionally be provided to secure or couple together the longitudinal members 428. For example, one or more circumferentially extending ring structures 429a can be provided for securing together the central portions 428c of the members 428. A ring structure 429b can optionally be provided for securing together the distal end portions 428c of the members 428. Ring structures 429a can optionally be referred to as central ring structures and ring structures 429b can optionally be referred to as small or end ring structures. The expandable structure is movable between a contracted position, for example for travel through a blood vessel to the treatment site, and an expanded position, for example for treating a lesion or occlusion in the blood vessel.

[0105] Each protruding element 427 of catheter 416 can have at least one electrode and optionally a plurality of electrodes. Each protruding element 427 can be substantially identical to the protruding elements 366 of catheter 346, except for the multiple electrodes on theprotruding elements 427 of catheter 416, and like reference numerals have been used to identify like elements of protruding elements 427, 366. The plurality of electrodes of each protruding element 427 can optionally be in the form of a first or distal electrode 431, a second or central electrode 432 and a third or proximal electrode 433. The multiple electrodes of the protruding element 427 are longitudinally spaced apart along the protruding element, for example at equal separation distances. Each electrode is disposed at or near the outer edge 367 of the protruding element, and each can be like any of the electrodes 373 of catheter 346. An insulated conductive lead of any suitable type, which can be like any of the leads 376 of catheter 346 and is not shown in FIG. 34, is carried by the elongate tubular member 417 for each of the electrodes 431-433 and is electrically connected at its distal end to the respective electrode. The conductive leads can extend along the tubular member, for example bundled together in any conventional manner. Each conductive lead of the expandable structure 426 is adapted for coupling to a suitable radio frequency generator, like radio frequency generator 46, to cause radio frequency energy to be delivered to the electrodes in any suitable manner, including as disclosed herein. The RF generator can optionally be configured to selectively or alternatively deliver RF energy in any suitable pulsed manner to any number of electrodes of the expandable structure 426 serving as a bipolar pair, including any pair or all of electrodes of a protruding element 427, with other electrodes of the expandable structure or protruding element serving as a return electrode. Such suitable pulsed manner can optionally include any pulsed manner disclosed herein.

[0106] One or more of the protruding elements 427 can optionally be coated with any suitable drug or medicament, for example including anti-proliferative drugs, the Limus family of drugs or paclitaxel.

[0107] Treatment catheter 416 can operate together with any suitable balloon catheter, including any balloon catheter of the invention, to treat a lesion or occlusion in a blood vessel, for example in any procedure disclosed herein, and together with the balloon can optionally be referred to as a treatment device or system of the invention. In an optional procedure, catheter 416 can be introduced into a blood vessel in any suitable manner, for example with the use of any suitable delivery catheter, so that expandable structure 426 of the catheter 416 is at the treatment site. In an optional treatment, the expandable structure is near or within a lesion or occlusion in the blood vessel. The expandable balloon of the balloon catheter can be delivered through the blood vessel, for example by means of the internal passageway 418 of the treatmentcatheter, such that the expandable balloon is slidably received or captured within the expandable structure or cage 426. Inflation of the balloon of the balloon catheter causes the expandable structure to move to its expanded or enlarged position and for the protruding elements 427 of the expandable structure to engage to lesion or occlusion and create fissures in the lesion or occlusion, expand the blood vessel or both. The pressurization of the balloon urges the outer edge 367 of each protruding element 427 radially outwardly to engage and score the lesion or occlusion. RF energy supplied to the electrodes of the protruding elements 427, for example to any pair of electrodes including sequential pairs of electrodes, can enhance the creation of fissures, enhance the scoring of the lesion or occlusion, enhance the expansion of the blood vessel by the balloon, enhance the effectiveness of any drug or medicament delivered by the protruding elements or otherwise or any combination of the foregoing, possibly by the creation of a spark between the electrodes. A sample spark 434 is shown in FIG. 34 between the distal electrode 431 and the central electrode 432 and between the central electrode 432 and the proximal electrode 433 of one of the protruding elements 427.

[0108] A method of the invention can include a combination of any of the following steps for accessing a blood vessel of a mammalian body occluded by a lesion is as follows. The method can include any combination of conventional guidewires, conventional delivery catheters, ablation guidewires of the invention, treatment guidewires of the invention, conventional balloon or other treatment catheters, balloon or other treatment catheters of the invention and protruding elements of the invention. A guidewire, for example any ablation guidewire of the invention, is introduced into the blood vessel and advanced through the vessel until the distal portion of the guidewire is in the vicinity of or nearby the lesion or occlusion formed by the lesion. Any suitable delivery catheter, for example delivery catheter of the invention, can be used for so introducing or delivering the guidewire.

[0109] The guidewire has at least one electrode, and optionally two electrodes, for forming a bipolar pair of electrodes. The delivery catheter can optionally have at least one electrode for participating in the bipolar pair of electrodes. The at least one electrode of the guidewire can be on the distal tip of the guidewire. The guidewire can optionally have at least two electrodes for forming the bipolar pair of electrodes. The two electrodes of the guidewire can optionally be two electrodes on the distal tip of the guidewire, for example extending distally side-by-side with each other. The two electrodes of the guidewire can optionally be a distal tip electrode and atleast one electrode located proximally of the distal electrode on the guidewire. The proximal electrode can optionally be an annular electrode. The at least one electrode of the delivery catheter can optionally be on the distal portion of the catheter, for example an annular electrode on the outside or in the internal delivery passageway of the catheter. The distal end of the ablation guidewire can optionally be stiffer than the remainder of the length of the catheter to facilitate advancement of the guidewire relative to the lesion or occlusion. The ablation guidewire can include a stiffening element in its distal end for providing such stiffening to the distal end.

[0110] If the passage of the guidewire, and optional delivery catheter, is impeded, obstructed or blocked by the lesion or occlusion, radio frequency energy can be supplied to at least two of the electrodes of the guidewire and delivery catheter to ablate the tissue of the lesion or occlusion. Such ablation can disintegrate or destroy the tissue of the lesion or occlusion and thus create a space through which the guidewire can further travel. The radio frequency energy can optionally be supplied to the distal tip electrode, with such electrode serving as the active electrode of the bipolar pair of electrodes. The supply of radio frequency energy can optionally be controlled or modulated as a function of data obtained from a sensor provided on the distal portion of the guidewire. The ablation may include creation of a spark at or near the distal electrode, which is advantageous to tissue destruction. The distal electrode of the bipolar pair may have a surface area that is less than the surface area of the proximal electrode, which can increase the likelihood of a spark at or near the distal electrode. If the advance of the guidewire is further impeded by the lesion or occlusion, further ablations can be performed until passage of the guidewire and delivery catheter through the vessel are acceptable.

[0111] Such advancement of the guidewire and optional delivery catheter relative to the lesion or occlusion may include traversing or crossing the lesion or occlusion. Such advancement of the guidewire and delivery catheter may include removing a sufficient amount of the tissue of the lesion or occlusion to permit a balloon or other treatment catheter to be positioned in the blood vessel in a suitable position for treating the blood vessel, which can optionally include expanding the blood vessel to increase blood flow through the blood vessel.

[0112] A method of the invention can include a combination of any of the following steps for treating a blood vessel. A microcatheter can be introduced into the blood vessel and advanced through a lesion. Where an ablation guidewire of the invention, and optionally a deliverycatheter, was required to access, cross or traverse the lesion or an occlusion, the delivery catheter can be withdrawn from the blood vessel and the microcatheter optionally advanced across the lesion over the ablation guidewire of the invention. The ablation guidewire can optionally be withdrawn from the blood vessel and the microcatheter advanced across the lesion with any suitable other guidewire. The microcatheter can optionally be a balloon catheter, a drug-eluting balloon catheter, an ablation catheter, any of the treatment or balloon catheters of the invention or any combination of the foregoing.

[0113] Upon placement of the microcatheter across the lesion, any treatment guidewire of the invention can be introduced through the microcatheter and advanced to the distal portion of the microcatheter. The microcatheter can be provided with a plurality of conductive elements, for example two conductive elements, on its distal portion and the treatment guidewire can be provided with a plurality of electrodes, for example two electrodes, on its distal portion that register respectively with the conductive elements on the treatment guidewire when the treatment guidewire is positioned in the microcatheter in situ for treatment. For longer lesions, a microcatheter with more than two conductive elements, for example four or six conductive elements, can be provided so that multiple treatments can be performed using the same microcatheter. In such a case, for example the guidewire would initially be placed so that its electrodes register with the two most distal conductive elements of the catheter for an initial treatment and then the guidewire would be retracted slightly so that its electrodes registers with the two most proximal conductive elements for a subsequent treatment or any combination thereof. It is appreciated that the electrodes of the guidewire can optionally sequentially register with any pair of conductive elements of the treatment catheter for sequential delivery of RF energy by the selected pair of conductive elements to the lesion or occlusion, for example sequentially along the length of the lesion or occlusion. The selected pair of conductive elements can optionally be referred to as a bipolar pair of conductive elements. The electrodes of the guidewire can be supplied with radio frequency energy to energize the selected conductive elements on the microcatheter and ablate the lesion. Such ablation, which may include the creation of a spark between the conductive elements, can facilitate the creation of fissures in the lesion or occlusion.

[0114] The microcatheter with conductive elements can include an inflatable balloon on the distal portion of the microcatheter overlying the conductive elements. The microcatheter caninclude a plurality of longitudinally-extending outer edges that are urged against the lesion with the inflatable balloon for scoring the lesion or occlusion. The inflatable balloon, optionally including longitudinally-extending outer edges, can be expanded and urged radially outwardly against the lesion or occlusion to create fissures in the lesion and thus expand the blood vessel to increase blood flow through the vessel. The lesion can be optionally ablated by the conductive elements to enhance the creation of fissures and expansion of the blood vessel. The lesion can be optionally abated by one or more electrodes mounted on the longitudinally-extending outer edges.

[0115] The microcatheter with conductive elements can include any suitable drug or medicament, including any of those disclosed therein. The drug can be coated on or carried by any longitudinally-extending outer edges utilized in the method. The drug or medicament can be coated on the balloon for delivery to the lesion. The drug or medicament can be releasably secured to at least a portion of the outside of the balloon, for example by suitable linkers as disclosed herein. The linkers can release the drug or medicament upon the occurrence of a controllable event, including any controllable event disclosed herein. The drug or medicament can be released from within the inflatable balloon. The drug or medicament can be contained in and released from an additional balloon mounted on the distal portion of the microcatheter overlying the inflatable balloon. The radio frequency energy delivered to the lesion by the microcatheter can enhance the embedding and retention of the drug or medicament in the vascular wall.

[0116] A method of the invention can include a combination of any of the following steps for treating a lesion or occlusion in a blood vessel. An expandable structure or cage on a distal portion of a catheter can be disposed over an inflatable balloon of a balloon catheter. A plurality of longitudinally-extending protruding elements with scoring elements or edges are carried by expandable structure or cage. Inflation of the balloon in the blood vessels urges the scoring elements or edges of the expandable structure against the lesion or occlusion for scoring the lesion and enhancing the formation of fissures in the lesion or occlusion. Ablation electrodes, a drug or medicament or both can be provided on the protruding elements for enhancing the treatment of the lesion or occlusion.

[0117] The invention improves the crossing or traversing of a lesion or occlusion in a blood vessel, and can include an ablation guidewire for ablating the lesion or occlusion to facilitatesuch crossing or traversing. The ablation guidewire can optionally be used with a delivery catheter having at least one electrode for bipolar pairing with an electrode of the ablation guidewire.

[0118] The invention improves treating a lesion or occlusion in a blood vessel, and can include a catheter with conductive elements that are respectively energized by radio frequency electrodes on a guidewire that can be advanced into the catheter. The catheter can include an inflatable balloon for creating fissures in the lesion or occlusion, which can be enhanced by the ablation. The balloon catheter can deliver a drug or medicament to the lesion or occlusion, the effectiveness of which can be enhanced by the delivery of radio frequency energy to the lesion or occlusion.

Claims

CLAIMSI claim:

1. A guidewire for treating a lesion in a blood vessel of a mammalian body, comprising an elongate member having a proximal portion and a distal portion, the distal portion adapted for insertion into the blood vessel for travel to the lesion, the proximal portion being configured to control movement of the distal portion during travel in the blood vessel, first and second electrodes mounted on the distal portion and an insulated conductive lead electrically coupled to each of the first and second electrodes and extending from the distal portion to the proximal portion of the elongate member and adapted for coupling to a radio frequency generator to cause radio frequency energy to be delivered by the at least one of the first and second electrodes to the lesion as part of a treatment procedure.

2. The guidewire of Claim 1, wherein each of the first and second electrodes is an active electrode for selectively delivering radio frequency energy to the lesion.

3. The guidewire of Claim 1, wherein the distal portion of the elongate member has a distal tip, at least the first electrode mounted on the distal tip for creating a space in the lesion to permit further advancement of the distal portion relative to the lesion.

4. The guidewire of Claim 3, wherein the first electrode is a ball electrode extending distally of the distal tip.

5. The guidewire of Claim 4, wherein the second electrode is a ball electrode extending distally of the distal tip alongside the first electrode, each of the first and second electrodes extending distally of the distal tip approximately the same distance and the first and second electrodes forming a bipolar pair of electrodes.

6. The guidewire of Claim 3, wherein the first electrode is semicircular in shape and extends distally of the distal tip.

7. The guidewire of Claim 6, wherein the second electrode is semicircular in shape and extends distally of the distal tip spaced from the first electrode, each of the first and second electrodes extending distally of the distal tip approximately the same distance and the first and second electrodes having respective distal ends and extending in a plane with a gap between the distal ends for forming a bipolar pair of electrodes.

8. The guidewire of Claim 3, wherein the first electrode extends distally of the elongate member has a first portion extending radially outwardly from the distal portion of theelongate member and a second portion angled relative to the first portion and extending radially inwardly.

9. The guidewire of Claim 8, wherein the second electrode extends distally of the elongate member and has a first portion extending radially outwardly from the distal portion of the elongate member and a second portion angled relative to the first portion and extending radially inwardly, each of the first and second electrodes extending distally of the distal tip approximately the same distance and the first and second electrodes having respective distal ends and extending in a plane with a gap between the distal ends for forming a bipolar pair of electrodes.

10. The guidewire of any of Claims 5, 7 or 9, further comprising dielectric member disposed in the gap between the distal ends of the first and second electrodes.

11. The guidewire of Claim 10, further comprising an electrical sensor disposed proximate the distal tip for measuring characteristics of the lesion, the electrical sensor selected from the group consisting of a pressure sensor, a flow sensor, a temperature sensor, a magnetic sensor, and a sensor to measure impedance.

12. The guidewire of Claim 3, wherein the first electrode extends distally of the distal tip and has a shape selected from the group consisting of a ball, a sphere, a semi sphere, two rings in a cross shape, a micro loop, a ring, a cross shape that tapers distally, a semicircle, a C- shape, an L-shape and any combination of the foregoing.

13. The guidewire of Claim 3, wherein the second electrode is mounted on the elongate member proximal of the distal tip, the first and second electrodes forming a bipolar pair of electrodes.

14. The guidewire of any of Claims 1 through 13, wherein each insulated conductive lead is a separate member, the separate members being joined together along the length of the elongate member.

15. The guidewire of Claim 13, wherein the second electrode has a surface area and the first electrode has a surface area relative to the surface area of the second electrode in the range selected from the group consisting of 1% to 30% and less than 10%.

16. The guidewire of Claim 13, wherein the insulated conductive lead of at least one of the first and second electrodes is selected from the group consisting of a wire, a braid, a helix and a hypotube.

17. The guidewire of Claim 1, wherein the elongate member includes a coaxial cable having the insulated conductive lead of one of the first and second electrodes as a center conductor, an insulating layer surrounding the center conductor, a shield surrounding the insulating layer and an outer jacket surrounding the shield.

18. The guidewire of Claim 1, wherein the first and second electrodes are mounted on the distal portion of the elongate member and longitudinally spaced apart from each other by an electrically-insulating material.

19. The guidewire of Claim 18, wherein the first electrode has a surface area and the second electrode has a surface area substantially equal to the surface area of the first electrode.

20. The guidewire of Claim 18, wherein the distal portion of the elongate member is formed by a flexible electrically-insulating material and has a distal tip, the first and second electrodes being mounted on the distal portion of the elongate member proximal of the distal tip.

21. A system for treating a lesion in a blood vessel of a mammalian body, comprising a guidewire having a proximal portion and a distal portion with a distal tip, the distal portion adapted for insertion into the blood vessel for travel to the lesion, the proximal portion being configured to control movement of the distal portion during travel in the blood vessel, the distal portion of the elongate member having a distal tip, a microcatheter for slidable disposition on the guidewire to the distal portion when the distal portion is in the blood vessel, and a first radio frequency electrode mounted on the distal tip of the guidewire and a second radio frequency electrode mounted on the distal portion and the microcatheter, the first and second radio frequency electrodes forming a bipolar pair of electrodes for treating the lesion.

22. The system of Claim 21, wherein the first electrode extends distally of the distal tip and has a shape selected from the group consisting of a ball, a sphere, a semi sphere, two rings in a cross shape, a micro loop, a ring, a cross shape that tapers distally, a semicircle, a C- shape, an L-shape and any combination of the foregoing.

23. The system of Claim 21, wherein the second radio frequency electrode is electrically coupled to an additional electrode mounted on the distal portion of the guidewire proximal of the first radio frequency electrode for delivering radio frequency energy to the second radio frequency electrode.

24. The system of Claim 21, wherein the second radio frequency electrode is mounted on the exterior of the microcatheter.

25. The system of Claim 21, wherein the second radio frequency electrode is mounted on the interior of the microcatheter.

26. A system for treating a lesion in a blood vessel of a mammalian body, comprising a guidewire having a proximal portion and a distal portion, the distal portion being formed of a flexible electrically-insulating material and adapted for insertion into the blood vessel for travel to the lesion, the proximal portion being configured to control movement of the distal portion during travel in the blood vessel, first and second electrodes mounted on the distal portion and longitudinally spaced apart from each other by an electrically-insulating material, an insulated conductive lead electrically coupled to each of the first and second electrodes and extending from the distal portion to the proximal portion of the elongate member and adapted for coupling to a radio frequency generator to cause radio frequency energy to be delivered to at least one of the first and second electrodes, a microcatheter for slidable disposition on the guidewire to the distal portion when the distal portion is in the blood vessel, and first and second conductive elements mounted on the microcatheter and configured for electrically coupling in situ with the respective first and second electrodes of the guidewire so as to serve as bipolar radio frequency electrodes for treating the lesion.

27. The system of Claim 26, wherein the microcatheter includes additional conductive elements.

28. The system of Claim 26, wherein the guidewire has a distal tip and the first and second electrodes are mounted on the distal portion proximal of the distal tip.

29. The system of Claim 28, wherein the microcatheter is a balloon catheter having an inflatable balloon overlying the first and second conductive elements.

30. The system of Claim 29, wherein the inflatable balloon is coated balloon with a drug.

31. The system of Claim 30, wherein the drug is selected from the group consisting of anti-proliferative drugs, the Limus family of drugs and paclitaxel.

32. The system of Claim 29, wherein at least part of the inflatable balloon is coated with linkers for securing a drug to the inflatable balloon, the linkers being activatable to release the drug in situ upon the occurrence of a controllable event.

33. The system of Claim 32, wherein the controllable event is the generation of pressure waves, heat, a magnetic field, a chemical reaction, light within the inflatable balloon and any combination of the foregoing.

34. The system of Claim 29, wherein the balloon catheter is provided with a passageway extending from the proximal portion to an opening inside the inflatable balloon for delivering a drug to the inflatable balloon, the inflatable balloon being formed with a plurality of micropores for delivering the drug to the lesion upon inflation of the inflatable balloon in situ.

35. The system of Claims 29 to 34, further comprising a plurality of protruding elements overlying the inflatable balloon in circumferentially spaced-apart positions, each of the plurality of protruding elements having a longitudinally-extending outer edge for scoring the lesion upon inflation of the inflatable balloon.

36. The system of Claim 35, wherein the plurality of protruding elements are mounted on the inflatable balloon.

37. The system of Claim 35, wherein each of the plurality of protruding elements has opposite ends coupled to the proximal portion.

38. The system of Claim 35, wherein each of the plurality of protruding elements has a cross section having a shape selected from the group consisting of substantially triangular and circular.

39. The system of Claim 35, wherein each of the plurality of protruding elements is coated with a drug.

40. The system of Claim 39, wherein the drug is selected from the group consisting of anti-proliferative drugs, the Limus family of drugs and paclitaxel.

41. The system of Claim 35, wherein at least one of the plurality of protruding elements has at least one protruding element electrode mounted on its longitudinally-extending outer edge.

42. The system of Claim 41, wherein the at least one protruding element electrode is a wire extending longitudinally through at least a portion of the at least one of the plurality of protruding elements.

43. The system of Claim 29, further comprising an additional balloon overlying the inflatable balloon, the additional balloon being formed with a plurality of micropores fordelivering a drug disposed within the additional balloon to the lesion upon inflation of the inflatable balloon in situ.

44. The system of Claim 43, wherein the balloon catheter is provided with a passageway extending from the proximal portion to an opening inside the additional balloon for delivering the drug to the additional balloon.

45. The system of Claim 43, wherein the inflatable balloon is a drug-coated inflatable balloon.

46. The system of Claims 43 to 45, further comprising a plurality of protruding elements overlying the additional balloon in circumferentially spaced-apart positions, each of the plurality of protruding elements having a longitudinally-extending outer edge for scoring the lesion upon inflation of the inflatable balloon.

47. A catheter for use with a guidewire to treat a lesion in a blood vessel of a mammalian body, comprising an elongate tubular member having an internal passageway adapted for introducing the elongate tubular member into the blood vessel over the guidewire, the elongate tubular member having a proximal portion and a distal portion, an expandable member mounted on the distal portion, a plurality of protruding elements overlying the expandable member in circumferentially spaced-apart positions, each of the plurality of protruding elements having a longitudinally-extending outer edge for scoring the lesion upon expansion of the expandable member and at least one of the plurality of protruding elements having first and second longitudinally spaced-apart protruding element electrodes mounted on its longitudinally-extending outer edge for treating the lesion.

48. The catheter of Claim 47, wherein the expandable member is an inflatable balloon.

49. The catheter of Claim 47, wherein the at least one of the plurality of protruding elements has an additional protruding element electrode mounted on its longitudinally-extending outer edge for treating the lesion.

50. A catheter for use with a balloon catheter having an inflatable balloon to treat a lesion in a blood vessel of a mammalian body, comprising an elongate tubular member having an internal passageway adapted for introducing the elongate tubular member into the blood vessel over the balloon catheter, the elongate tubular member having a proximal portion and a distal portion, the distal portion including an expandable structure for overlying the inflatable balloonof the balloon catheter, a plurality of protruding elements mounted on the expandable structure in circumferentially spaced-apart positions, each of the plurality of protruding elements having a longitudinally-extending outer edge for scoring the lesion upon expansion of the inflatable balloon and at least one of the plurality of protruding elements having first and second longitudinally spaced-apart protruding element electrodes mounted on its longitudinally- extending outer edge for treating the lesion.

51. The catheter of Claim 50, wherein the at least one of the plurality of protruding elements has an additional protruding element electrode mounted on its longitudinally-extending outer edge for treating the lesion.

52. The catheter of Claim 50, wherein the expandable structure is an expandable cage structure.

53. The catheter of Claim 50, wherein the first and second longitudinally spaced-apart protruding electrodes forming a bipolar pair of electrodes.

54. A system for treating a lesion in a blood vessel of a mammalian body, comprising a guidewire having a proximal portion and a distal portion with a distal electrode, the distal portion adapted for insertion into the blood vessel for travel to the lesion and the proximal portion being configured to control movement of the distal portion during travel in the blood vessel, a balloon catheter having an internal passageway adapted for introducing the balloon catheter into the blood vessel over the guidewire, the balloon catheter having a distal portion with an inflatable balloon, an elongate tubular member having an internal passageway adapted for introducing the elongate tubular member into the blood vessel over the balloon catheter, the elongate tubular member having a distal portion with an expandable structure for overlying the inflatable balloon of the balloon catheter, a plurality of protruding elements mounted on the expandable structure in circumferentially spaced-apart positions, each of the plurality of protruding elements having a longitudinally-extending outer edge for scoring the lesion upon expansion of the inflatable balloon and at least one protruding electrode mounted on its longitudinally-extending outer edge for treating the lesion, the distal electrode of the guidewire and the protruding electrode of the elongate tubular member forming a bipolar pair of electrodes.

55. The system of Claim 54, wherein the distal portion of the guidewire has a distal tip, the distal electrode mounted on the distal tip.

56. The system of Claim 55, wherein the distal electrode has a shape selected from the group consisting of a ball, a micro loop and a cross shape that tapers distally.

57. The system of Claim 54, where in the expandable structure is an expandable cage structure.

58. A method of accessing a blood vessel of a mammalian body occluded by a lesion, advancing a guidewire having a distal portion into the blood vessel until the distal portion is nearby the lesion, providing radio frequency energy to a distal electrode mounted on the distal portion of the guidewire to ablate the lesion and create space to permit further travel of the distal portion through the lesion and advancing the guidewire further into the lesion.

59. The method of Claim 58, wherein the distal portion of the guidewire has a distal tip and the distal electrode is mounted on the distal tip and extends forwardly of the distal tip.

60. The method of Claim 59, further comprising an additional distal electrode mounted on the distal tip and extending forwardly of the distal tip alongside the first-named distal electrode.

61. The method of Claim 58, further comprising a proximal electrode mounted on the distal portion proximal of the distal electrode, the distal electrode and the proximal electrode forming a bipolar pair of electrodes.

62. The method of Claim 58, wherein the providing radio frequency energy step includes providing radio frequency energy as a function of data obtained from a sensor on the distal portion.

63. The method of Claim 58, wherein the step of advancing the guidewire further into the lesion includes crossing the lesion with the guidewire.

64. The method of Claim 63, further comprising advancing a microcatheter across the lesion and ablating the lesion with the microcatheter.

65. The method of Claim 64, wherein the microcatheter is a balloon catheter.

66. The method of Claim 65, wherein the ablating step includes ablating the lesion with a plurality of electrodes mounted respectively on a plurality of longitudinally-extending outer edges urged against the lesion with a balloon of the balloon catheter.

67. A method of treating a blood vessel partially occluded by a lesion, providing a microcatheter formed from an elongate tubular member having a distal portion with an outer surface and an empty internal passageway, a proximal conductive element and a distalconductive element provided on the distal portion and extending from the outer surface to the internal passageway, advancing the distal portion of the elongate tubular member through the partially occluded lesion so that the outer surface engages the lesion, supplying radio frequency energy to the proximal conductive element and the distal conductive element inside the internal passageway, and ablating the lesion with the proximal conductive element and the distal conductive element.

68. The method of Claim 67, wherein the supplying step includes advancing a distal portion of a guidewire into the empty internal passageway and supplying the radio frequency energy to the proximal conductive element and the distal conductive element by means of the distal portion of the guidewire.

69. The method of Claim 68, wherein the distal portion of the guidewire includes a proximal electrode and a distal electrode for registering respectively with the proximal conductive element and the distal conductive element.

70. The method of Claim 67, further comprising a first additional conductive element and a second additional conductive element provided on the distal portion and extending from the outer surface to the internal passageway, ceasing the supply of radio frequency to the proximal conductive element and the distal conductive element, supplying radio frequency energy to the first additional conductive element and the second additional conductive element inside the internal passageway, and ablating another portion of the lesion with the first additional conductive element and the second additional conductive element.

71. The method of Claim 70, wherein the distal portion of the guidewire includes a proximal electrode and a distal electrode, further comprising respectively registering the proximal electrode and the distal electrode with the proximal conductive element and the distal conductive element for ablation by the proximal conductive element and the distal conductive element and then respectively registering the proximal electrode and the distal electrode with the first additional conductive element and the second additional conductive element for ablation by the first additional conductive element and the second additional conductive element.

72. The method of Claim 67, wherein the microcatheter is a balloon catheter, further comprising inflating a balloon on the distal portion to treat the lesion with the balloon.

73. The method of Claim 72, further comprising delivering a drug to the lesion with the balloon.

74. The method of Claim 72, wherein the proximal conductive element and the distal conductive element on the outer surface are inside the balloon.

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