Catheter apparatus with telescoping lumen catheters and its use in methods for treating vasculatures

The invention provides for methods and catheter apparatus for passing one or more guidewires (via the use of one or more telescoping guidewire lumens) through a chronic total occlusion of a vasculature. The catheter apparatus may include: a catheter shaft having a distal end; one or more telescoping guidewire lumen catheters passing longitudinally through the shaft, wherein the one or more guidewire lumen catheters are capable of telescoping beyond the distal end of the catheter shaft; an expansible distal portion of the shaft; and a retractable sheath covering at least a portion of the expansible distal portion of the shaft, wherein retracting the retractable sheath from the expansible distal portion of the shaft directly activates the expansible distal portion of the shaft causing expansion of the expansible distal portion of the shaft.

FIELD OF THE INVENTION

The invention relates generally to apparatus and methods for treating vasculatures, and, more particularly, to methods and apparatus for passing one or more guidewires through a chronic total occlusion of a vasculature via the use of a catheter apparatus configured to contain one or more telescoping lumen catheters.

BACKGROUND OF THE INVENTION

A chronic total occlusion in a coronary artery, peripheral artery, vein, dialysis fistula, or other types of vasculature represents a challenge for percutaneous treatment. Percutaneous treatments are generally preferred revascularization options as compared to bypass surgery. Continuing improvements in equipment specifically developed for chronic total occlusions have allowed success rates to improve. Although the success rates for these types of procedures have improved, the procedures for percutaneous treatments still suffer from several drawbacks. Patients without a successful percutaneous treatment may need to undergo bypass surgery or experience continuing symptoms from the occlusions.

A major obstacle within a chronic total occlusion may often be encountered while attempting to advance a guidewire across the chronic total occlusion in a vasculature. A maximum resistance may be met at the most proximal point of the lesion, i.e. the firm, fibrous cap. While being advanced, a guidewire may tend to deflect away from the fibrous cap towards the adventitial layer, often entering a false lumen. This off-axis displacement of the guidewire often may result in a procedural failure.

Successful passage of the guidewire may also be obstructed by randomly located calcified regions of atherosclerotic plaque within the mass of the lesion. Microchannels within the obstruction may be desirable targets for the tip of the guidewire. However, these soft spots within the lesion are difficult to identify angiographically and are dispersed randomly within the matrix of the lesion.

Coronary arteries and other vasculatures tend to be non-linear conduits, often coursing over the surface of the epicardium and other tissues. The success of current technology is limited by this type of geometry. In current systems, a guidewire or currently available catheter is advanced down a vasculature to the level of the obstruction. At the point of the obstruction, the guidewire advancement may tend to proceed along the outer, greater curvature of the vasculature. Even a guidewire centered within the vasculature at the proximal edge of the chronic total occlusion may tend to proceed toward the outer, greater curvature of a vasculature.

As a result, only a minor portion of the surface area of the obstruction may be encountered with sufficient force to allow passage of the guidewire. On many occasions, the angle of encounter and/or the force applied to the fibrous cap may not be sufficient for crossing the fibrous cap with the guidewire. If the tip of the guidewire is curved prior to placement through the support catheter, direct longitudinal force may be compromised as the wire is advanced off axis. If a rapid exchange catheter system is used as catheter support, the guidewire may buckle within the guide-catheter resulting in suboptimal longitudinal guidewire force.

At times, a single lumen angioplasty balloon may be inflated just proximal to the chronic total occlusion in an attempt to center the guidewire in the vessel lumen and provide additional support for the guidewire. Atherosclerotic lesions tend to be asymmetric with an eccentric true lumen. Therefore, attempts to limit the guidewire to the central axis of the vessel lumen may result in lower rates of procedural success.

Generally, needs exist for improved apparatus and methods for treating vasculatures. More specifically, needs exist for improved apparatus and methods for efficiently and effectively passing a guidewire through a chronic total occlusion in a vasculature.

SUMMARY OF THE INVENTION

Embodiments of the present invention solve many of the problems and/or overcome many of the drawbacks and disadvantages of the prior art by providing an apparatus and method for treating vasculatures.

In particular, embodiments of the invention may accomplish this with an apparatus for efficiently and effectively passing a guidewire through a chronic total occlusion in a vasculature. The apparatus may have a flexible shaft having a distal end, one or more guidewire lumens having a distal end and passing longitudinally through the shaft, and a positioning means for positioning distal ends of the one or more guidewires relative to an inner wall of an external lumen. The apparatus may have one or more lumen catheters (such as e.g. 3), which may be jointly or independently movable such that the distal end of the one or more lumen catheters telescopes beyond the distal end of the flexible shaft. The one or more lumen catheters may also be jointly or separately (i.e. independently) operable. An actuator may control the operation of such lumen catheters. The lumen catheters are configured for passage of a guidewire.

The positioning means may be an expansible scaffold initially in a non-expanded state. A retractable sheath may surround the expansible scaffold and the retractable sheath may be retracted for expanding the expansible scaffold.

The positioning means may also be one or more balloons where the one or more balloons are inflated through an inflation port running longitudinally in the shaft. The positioning means may also include guidewire lumens coupled to or otherwise disposed within the expansible scaffold. The positioning means may also include inflatable means surrounding distal ends of the guidewire lumens. The inflatable means may or may not be located within an expansible scaffold.

The positioning means may also be a rotatable core within the shaft. The positioning means may also include a deflectable tip on the catheter. The positioning means may also include a shape-memory material integrated with the guidewire lumens.

A method of operating a catheter apparatus may include providing a catheter apparatus including a flexible shaft, one or more guidewire lumens passing longitudinally through the shaft, one or more guidewires within the one or more guidewire lumens, and a positioning means, inserting a guide catheter into a vasculature with a chronic total occlusion, inserting the catheter apparatus into the guide catheter, activating the positioning means for positioning the one or more guidewires relative to the chronic total occlusion, and advancing the one or more guidewires through the one or more guidewire lumens and into contact with the chronic total occlusion.

The one or more guidewires may be passed through the chronic total occlusion. The catheter apparatus may be withdrawn from the vasculature while leaving the one or more guidewires in place. The one or more guidewires may be withdrawn from contact with the chronic total occlusion and the one or more guidewires may be advanced through the one or more guidewire lumens into contact with the chronic total occlusion repeatedly until a suitable site for passing the one or more guidewires through the chronic total occlusion is found. The positioning means may be activated before each advancing of the one or more guidewires through the one or more guidewire lumens into contact with the chronic total occlusion.

Another embodiment of the present invention may be a catheter apparatus including a multi-lumen main shaft; one or more guidewire lumens extending from a distal end of the multi-lumen shaft with lumens within the one or more guidewire lumens contiguous with at least one of the multi-lumens of the multi-lumen main shaft; an expansible support structure coupled to the distal end of the multi-lumen shaft; one or more loops corresponding to each of the one or more guidewire lumens, wherein the one or more loops corresponding to each of the one or more guidewire lumens are coupled to the expansible support structure, and wherein the one or more loops corresponding to each of the one or more guidewire lumens project inward from the plane of the expansible support structure; and wherein the one or more guidewire lumens are threaded through the corresponding one or more loops.

Another embodiment of the invention is a catheter apparatus including: a main catheter shaft; one or more lumen telescoping catheters, each lumen catheter configured for passing over one or more guidewire; each lumen catheter capable of telescoping in and out from a distal end of the main catheter shaft; and an expansible support structure coupled to the distal end of the main catheter shaft, the expansible support structure configured so that each telescoping lumen microcatheter can telescope in and out of the expansible support structure. The main catheter shaft may have one or more telescoping lumen catheter shafts. The one or more telescoping lumen catheters may pass through the one or more telescoping lumen catheter shafts. The telescoping lumen catheters may be coupled to the expansible support structure. The expansible support structure may be self-expanding and it may be a scaffold.

The expansible support structure may be capable of surrounding the one or more telescoping lumen catheters. When the expansible support structure (e.g. scaffold) surrounds the one or more lumen catheters, the expansible support structure has one or more inward facing loops each corresponding to one or more of the telescoping lumen catheters and wherein each of the one or more telescoping lumen catheters are threaded through the corresponding one or more loops. These one or more inward facing loops may be coupled to the expansible support structure by loop connections. The expansible support structure may include closed cells. These closed cells, for example, may be approximately hexagonal with expansible S-shaped connectors on two opposing sides of the hexagon. The expansible support structure may be made from a shape memory alloy such as e.g. nitinol.

The apparatus may also include a retractable sheath covering at least a portion of the expansible support structure of the main catheter shaft, wherein retracting the sheath from the distal portion of the shaft directly activates the expansible support structure. The retractable sheath may be advanced around the expansible support structure to compress the expansible support structure. In addition, the apparatus may include an actuator. Operation of the actuator may control movement of the one or more telescoping lumen catheters.

The one or more telescoping lumen catheters may be capable of separately telescoping in and out of the main catheter shaft. For example, one telescoping lumen catheter may be capable of separately telescoping in and out of the main catheter shaft. Alternatively, two or more telescoping lumen catheters may be capable of separately telescoping in and out of the main catheter shaft. In one embodiment, the one or more telescoping lumen catheters surround the main catheter shaft and the distal tip of each of the one or more telescoping lumen catheters is coupled to the support structure.

Another embodiment of the invention is a catheter apparatus including a shaft having a proximal and a distal end; one or more telescoping lumen catheters surrounding the shaft, each telescoping lumen catheter configured for passing over one or more guidewires; each telescoping lumen catheter capable of telescoping the distal end the main catheter shaft; an support structure coupled to the distal end of the shaft, wherein the distal end of each lumen catheter is coupled to the scaffold. The coupling may be on the interior of the support structure (e.g. scaffold). The support structure may be self-expansible. The expansible support structure may be capable of surrounding the one or more telescoping lumen catheters. When the support structure surrounds the lumen catheters, the structure has one or more inward facing loops corresponding to each corresponding to one or more the telescoping lumen catheters and wherein each of the one or more telescoping lumen catheters are threaded through the corresponding one or more loops. The one or more inward facing loops may be coupled to the expansible support structure by loop connections. The expansible support structure may include closed cells which are approximately hexagonal with expansible S-shaped connectors on two opposing sides of the hexagon. Apparatus may also include a retractable sheath covering at least a portion of the expansible support structure of the main catheter shaft, wherein retracting the sheath from the distal portion of the shaft directly activates the expansible support structure.

Another embodiment of the invention is a method for advancing a guidewire through an obstructed vasculature including: inserting the catheter apparatus having a main shaft and one or more telescoping lumen catheter is passing, each telescoping lumen catheter configured for passing over one or more guidewires into an obstructed vasculature; expanding an expansible support structure on the distal end of the main shaft; telescoping one or more telescoping lumen catheters in and out of main catheter shaft and through the expanded support structure; and advancing one or more guidewires through the one or more telescoping lumen catheters and into contact with an obstruction. The main catheter shaft may have one or more telescoping lumen catheter shafts through which one or more telescoping lumen catheters is passing. The one or more telescoping lumen catheters may telescope individually. The one or more telescoping lumen catheters may provide support to the one or more guidewires.

The support structure may be a scaffold. The support structure may also be made from a shape memory alloy such as e.g. nitinol. The support structure may also be made of a self-expanding. When the support structure is self-expanding, the step of expanding the expansible support structure includes withdrawing a sheath surrounding the support structure. The expansible support structure may surround the one or more telescoping lumen catheters and may have one or more inward facing loops corresponding to each corresponding to one or more the telescoping lumen catheters and wherein each of the one or more telescoping lumen catheters are threaded through the corresponding one or more loops.

The step of telescoping may include telescoping the telescoping lumen catheters out of the main catheter until resistance is felt. The method may also include sequentially advancing the one or more telescoping lumen catheters. The step of telescoping may further include measuring the distance a telescoping lumen catheter advances and the method may also further include advancing the one or more guidewire through the telescoping lumen catheter that advances the furthest.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the present invention may include apparatus and methods for advancing one or more guidewires through an obstructed vasculatures such as e.g. chronic total occlusions (CTOs) in vasculatures. The support and centering functionality has application beyond CTOs, even though the preferred embodiments described herein are directed to support and centering to facilitate a guidewire to cross through a CTO.

Embodiments of the present invention may incorporate several features to successfully pass one or more guidewires through an obstructed vasculature such as e.g. a chronic total occlusion. Features of the present invention may include multiple lumens constructed within a catheter shaft, expansion, or activation of a distal tip of a catheter apparatus for creating a scaffold effect, and/or decentralization of the guidewire lumens after activation or distal catheter repositioning for allowing multiple sections of a fibrous cap to be forcefully engaged by a guidewire. Features of the present invention may further include one or more lumen catheters that may be independently (separately) or jointly movable and, therefore, be advanceable beyond the distal end of the catheter shaft. For example, the multiple lumen catheters may be telescoping beyond the distal end of the catheter shaft. Embodiments of the present invention may optimize advancement of the one or more guidewires into multiple sections of a fibrous cap of a chronic total occlusion with reasonable force.

In embodiments of the present invention, one or more over-the-wire lumens may be constructed within a shaft of a catheter apparatus. Embodiments of the present invention may preferably use two or more lumens such as e.g. three lumens. The lumen may be configured to accommodate lumen catheters. The lumen catheters may be independently advanceable. The lumen catheters may be advanceable so that the lumen catheters may extend (e.g. telescope) beyond the shaft of the catheter apparatus. In addition, the lumen catheters may retract into the shaft of the catheter apparatus. Larger vasculatures, such as coronary arteries, may accommodate higher profile catheters and allow use of additional lumens. Each lumen may accommodate at least a 0.014″ diameter guidewire. Other sized lumens and guidewires may be accommodated based upon the desired end use. Standard off-the-shelf or customized guidewires may be used. For example, in addition to traditional guidewires, embodiments of the present invention may be used with guidewires including, but not limited to, steerable, hydrophilic, Teflon-coated, heparin-coated, ball-tip, J-tip, spiral tip, angulated wire and others.

Embodiments of the present invention may be combined with other types of catheter devices. The positioning systems and methods of the present invention may be to deliver and/or direct other catheters towards a desired position. For example, a vibrating catheter or other specialized catheter may be directed towards a chronic total occlusion or other location in a vasculature. A microcatheter with a distal positioning device, including, for example, one or more balloons that may be inflated individually, sequentially or simultaneously, or other features, may be placed in proximity to a chronic total occlusion. A positioning system may steer the microcatheter away from a wall of a vessel, as it probes a cap of a chronic total occlusion. Microcatheters with angulation or other features may be placed in proximity to a chronic total occlusion where the angulation steers away from a wall of a vessel, probes a cap of a chronic total occlusion or otherwise changes directions. A catheter portion and/or sheath of embodiments of the present invention may be large enough to deliver and/or position specialized catheters to a desired location. Positioning devices may then be used to position the specialized catheters in a beneficial manner for a procedure.

In particular, embodiments of the present invention may deliver energy via the guidewires through radio frequencies and/or lasers. Furthermore, other types of energy may be delivered such as direct conductive heat energy, infrared or other types of energy that may be useful in particular applications. Various types of guidewires and/or delivering energy via guidewires may allow for various types of treatments. The external diameter of a catheter apparatus of the present invention may allow passage through a standard guide catheter. The outer surface of a catheter apparatus of the present invention may be coated with hydrophilic material to allow easier passage through the guide catheter. With alternate dimensions, the catheter apparatus of the present invention may be used in peripheral vessels. In this situation, a guide catheter may not be necessary to insert the device into the vasculature.

FIGS. 1A-1Kshow a self-expanding catheter apparatus11. The external diameter of the self-expanding catheter apparatus11may pass through a sheath19.

The sheath19may be a separate element surrounding the distal end of the catheter apparatus11to maintain the catheter apparatus11in an inactive state. The sheath19may have a rounded or tapered end for facilitating passage through a vasculature. Other end configurations are possible depending on particular uses.

Additional embodiments of the sheath may be shown inFIGS. 1J-1K. A sheath68,69may be used to lower a profile of a self-expanding distal portion13of the catheter apparatus11, which may preferably be a nitinol component, during insertion and removal of the catheter apparatus11from a vasculature. A sheath68may have a shorter configuration, as shown inFIG. 1J, covering at least a distal self-expanding component, preferably a nitinol element, on the catheter apparatus11. The sheath68, however, may preferably be long enough to correspond to the length of the treated vasculature, i.e., long enough to cover the portion of the catheter extending outside of a guide catheter and into the vasculature. This sheath configuration may function by insertion through a guide catheter and advancement into a treated vasculature. The sheath68may be attached60to a solid core guidewire and/or flexible device67. The solid core guidewire and/or flexible device67may be long enough to traverse a guide catheter. The solid core guidewire and/or flexible device67may be a solid structure with no internal lumens and may preferably be made of plastic or similar materials. The solid core guidewire and/or flexible device67may be manipulated from outside the body, preferably by means of an expanded element64at a proximal end of the solid core guidewire and/or flexible device67. The solid core element67may parallel the catheter apparatus11through a guide catheter. A distal portion58of the sheath68may be flared to fit a self-expanding portion13of the catheter apparatus device11. The distal portion58may also have one or more radiopaque or other types of markers54. The sheath68may have a stop point to allow withdrawal of the sheath68to a predetermined position, which may also facilitate resheathing of the catheter apparatus11.

Alternatively, as shown inFIG. 1K, a sheath69may have a longer length, completely surrounding an intravascular portion of the catheter apparatus11during insertion and removal. The sheath69may be a flexible with a roughly cylindrical shape. The sheath69may preferably be made of plastic or other similar materials. This sheath configuration may have a larger profile element62at an extra-vascular, proximal end, allowing for easier handling and movement of the sheath69. A distal portion66of the sheath69may be flared to fit a self-expanding portion13of the catheter apparatus device11. The distal portion66may also have one or more radiopaque or other types of markers56. The sheath69may have a stop point to allow withdrawal of the sheath69to a predetermined position, which may also facilitate resheathing of the catheter apparatus11. The sheath69may be used in conjunction with a guide catheter or may function without a guide catheter in a non-coronary vasculature.

A body or shaft23of the catheter apparatus11may be made of a flexible plastic material or any other similar substance. A hydrophilic coating may or may not be added to the outer surfaces of the catheter apparatus11. One or more hubs21corresponding to one or more guidewires15and one or more lumens17may be disposed at a proximate end29of the catheter apparatus11.

The one or more hubs21may be marked, color-coded, numbered or may otherwise differentiate between one another. Identification of individual guidewire lumens may allow more effective use of embodiments of the present invention. With marking, users may improve their ability to identify which guidewire lumen may be preferably used during a procedure. For example, if a particular guidewire lumen is in a preferable location relative to other guidewire lumens an operator may desire a quick and reliable method of inserting a guidewire through that particular guidewire lumen. Marking may save time and effort by eliminating trial and error to determine a desired guidewire lumen. Alternatively, marking may be useful for applications other than treatment of occluded vasculatures, such as steering guidewires through vasculatures via various lumens. For example, marking can allow embodiments of the present invention to be used in other areas and/or conditions of a vasculature, such as traversing the tortuous coronary arteries. Distal and proximal ends of the guidewire lumens may be similarly marked to identify the guidewire lumens. Distal ends or structures on distal ends of the guidewire lumens may be marked such that the user may identify a preferred guidewire lumen while the catheter apparatus is within a patient. Marking with radiopaque or other types of markers may include temporary structures within the guidewire lumens. For example, markers may be present on stylets within the guidewire lumens. The stylets may be removed if desired to reduce mass or otherwise improve efficiency of a procedure.

The one or more hubs21may allow introduction of stylets or other structures that run through the catheter apparatus to render it stiff or to remove debris from its lumen. The one or more hubs21may also allow passage of one or more guidewires15.

Generally, a distal portion13of the catheter apparatus11may function as a scaffold-type structure. The distal portion13of the catheter apparatus11may stabilize the catheter apparatus11within a vasculature lumen as one or more guidewires15are advanced into a chronic total occlusion. One or more guidewires15may be threaded through one or more lumens17within the catheter apparatus11. The distal portion13of the catheter apparatus11is preferably self-expanding.FIG. 1Bshows the distal end25of the catheter apparatus11in an expanded state.FIG. 1Cshows a cross section of the catheter apparatus11with a retractable sheath19surrounding the body23. The retractable sheath19may be retracted by moving the retractable sheath towards the proximate end29of the catheter apparatus11. The distal portion13of the catheter apparatus11may include an activated scaffold structure27to stabilize the catheter apparatus11. The activated scaffold structure27may expand to match a diameter of the vasculature lumen upon retraction of the retractable sheath19.

Nitinol and/or stainless steel may be incorporated into the scaffold structure27. Nitinol is an illustrative example of a shape memory alloy. Other shape memory alloys or other similar substances may be used. Generally, after a sample of a shape memory alloy has been deformed from its original crystallographic configuration, the shape memory alloy regains its original geometry by itself. This property of shape memory alloys may allow for expansion of the scaffold structure27after retraction of the retractable sheath19. The nitinol and/or stainless steel scaffold structure27may create a stent-like mesh. The scaffold structure27may form the surface of the distal portion13of the catheter apparatus11.

FIG. 1Hshows an inactive scaffold structure31. The inactive scaffold structure31may be advanced over a guidewire into a chronic total occlusion with a retractable sheath19in place to constrain the self-expanding but inactive scaffold structure31. The retractable sheath19may cover the inactive scaffold structure31. When the inactive scaffold structure31is properly positioned, the retractable sheath19may be retracted by an appropriate retraction means. As the retractable sheath19is retracted, the inactive scaffold structure31of the catheter apparatus11may become active and may flare out. During a flare out process, the inactive scaffold structure31may self-expand to assume a larger diameter to roughly approximate the diameter of the vasculature in the location of the distal portion13of the catheter apparatus11.

The retraction of the retractable sheath19may be a continuous or step-wise process. For example, the retractable sheath19may be retracted in one operation by a user until the scaffold structure31is fully exposed. Alternatively, the retractable sheath19may be retracted in increments less than that required for full expansion of the scaffold structure31. Stop points during refraction of the retractable sheath19may allow for predetermined quantities of expansion of the scaffold structure31. For example, if a procedure required less than full expansion of the scaffold structure31, a stop point short of full retraction of the retractable sheath19may be chosen.

The conversion and expansion of the inactive scaffold structure31into an active scaffold structure27may create a relatively stable platform from which to advance the one or more guidewires15into multiple sections of the chronic total occlusion. The activated catheter apparatus11with the retractable sheath19retracted may have an activated scaffold structure shaped as a truncated cone or other suitable shape. A surface33of the expanded distal end13of the catheter apparatus11may consist of a “skin” of the scaffold structure27. An end cap35may or may not cover the distal end35of the catheter apparatus11. The end cap35may preferably be made of an impervious expandable polymer, but other similar substances may be used.

FIG. 1Dshows an activated scaffold structure27that may be filled with an expandable polymer or similar material. The expandable polymer or similar material may fill the scaffold structure27to form a truncated, conical or other appropriate shape for securing the catheter apparatus11within the vasculature lumen. The expandable polymer may support distal portions of one or more guidewire lumens17. Upon expansion of the expandable polymer, the embedded lumen ends37may flare out correspondingly with the end cap35.FIG. 1Eshows a cross section of the catheter apparatus11with the retractable sheath19surrounding the shaft23.FIG. 1Fshows an end view of the expanded end cap35with embedded guidewire lumens17.

A skin33may surround the expandable polymer or similar material. The skin33may be a temporary metal “stent.” The metal stent may be a mesh type structure. The metal stent may become a truncated conical shape after expansion or any other suitable shapes.

The a-b dimension39indicated inFIG. 1Dmay shorten when the retractable sheath19is removed from scaffold structure27. The degree of shortening of the a-b dimension39may vary depending on the degree of expansion, the materials used, etc.

The retractable sheath19may be refracted to a stop point. The stop point may prevent over-retraction of the retractable sheath19. A retractable sheath19at the stop point may facilitate re-sheathing of the scaffold structure27.

FIG. 1Gshows multiple guidewire lumens17that may be suspended within a scaffold structure27without using an expansible polymer or similar filler. A skin33may be made of nitinol, stainless steel, or another expansible substance. The one or more guidewire lumens17may extend to the distal end25of the scaffold structure27. The scaffold structure27may begin roughly at a transition point41. The one or more guidewire lumens17may or may not be embedded in an end cap35. The end cap may an impervious plastic material.

FIG. 1Ishows a catheter apparatus with an expandable skin33and a deflectable tip43. The deflectable tip43may be rotatable or otherwise moveable. The deflectable tip43may be rotatable with a rotator45or other similar device at the proximate end29of the catheter apparatus11. The embodiment depicted inFIG. 1Ipreferably does not include and end cap35. The lack of an end cap35may allow for freedom of movement of the deflectable tip43. The distal portion13of the catheter apparatus11may flare after the retractable sheath19is retracted. A single, centrally located deflectable lumen47may allow a guidewire15to be advanced in numerous planes. The deflectable tip43may allow for controlled probing of the fibrous cap of a chronic total occlusion.

Other embodiments of the present invention may include one or more balloons at or near a distal end of a catheter apparatus. The one or more balloons may be circumferential. Alternatively, the one or more balloons may be offset and placed longitudinally. Other positions and arrangements are possible depending on particular situations.

FIG. 2Ashows an embodiment of the present invention with a balloon53that may be placed longitudinally near a distal tip55of a catheter apparatus51. The balloon53may parallel the long axis of a shaft59of the catheter apparatus51. Inflation of the balloon53may deflect the position of one or more guidewire lumens57relative to the fibrous cap of a chronic total occlusion. The balloon53may be inflated to a diameter that may buttress the catheter apparatus51against a wall of the vasculature lumen. The balloon53may then be deflated, the catheter apparatus51rotated, and the balloon53reinflated.

FIG. 2Bshows a cross section of the catheter apparatus51. The balloon53may be inflated and deflated through an inflation port65. The inflation port65may pass through the shaft59to connect the balloon53to a proximate end63of the catheter apparatus51. This method may result in one or more guidewires59probing various sections of the fibrous cap. One or more hubs61at the proximate end63of the catheter apparatus51may allow passage of the one or more guidewires59. Stylets or other similar structures may be inserted or reinserted into the catheter apparatus51to facilitate rotation.

FIG. 3Ashows an embodiment of the present invention with a first longitudinal balloon73and a second longitudinal balloon75positioned near a distal end77of a catheter apparatus71. More balloons may be used for additional or different control of the catheter apparatus. The multiple balloons73,75may be inflated individually, simultaneously, alternatively or sequentially depending on the particular circumstances. The pattern of inflation and/or deflation of the multiple balloons73,75may allow redirection of a distal catheter tip79relative to a fibrous cap of a chronic total occlusion. Repositioning of the distal catheter tip79may permit more complete interrogation of the fibrous cap with one or more guidewires81. One or more hubs83at the proximate end85of the catheter apparatus71may allow passage of the one or more guidewires81through a shaft87.

FIG. 3Bshows a cross section of the catheter apparatus71. One or more guidewire lumens89may pass through the catheter apparatus71. Embodiments of the present invention may be constructed with multiple inflation ports (not shown) or with one inflation port91servicing the multiple balloons73,75. If the latter option is utilized, the balloon materials may be constructed to allow selective, and/or sequential inflations at increasing balloon pressures. The balloons73,75may be positioned at various angles relative to one another around the circumference of the shaft87.

FIG. 4Ashows an embodiment of the present invention with a balloon103with a distal surface105in a catheter apparatus101. The balloon103may be flat, cylindrical, or any other suitable configuration. Additionally, the balloon103may be sectioned. One or more guidewire lumens107may be extruded through the balloon material. The balloon103may be inflated to match the inner diameter of the vasculature lumen.FIG. 4Bshows an end view of the catheter apparatus101. As the balloon103expands, the one or more guidewire lumens107extruded through the balloon103may diverge relative to one another in reaction to expansion of the balloon103. The divergence may allow one or more guidewires109to probe various sections of the fibrous cap of the chronic total occlusion. One or more hubs111at the proximate end113of the catheter apparatus101may allow passage of the one or more guidewires109.FIG. 4Cshows a cross section of the catheter apparatus101. A balloon inflation port115may pass through a shaft117with the one or more lumens107to inflate and/or deflate the balloon103.

FIG. 5Ashows a catheter apparatus121with an inner core123within an outer core125. The inner core123may contain one or more lumens127. Embodiments of the present invention may preferably include two or more lumens127.FIG. 5Billustrates an embodiment with two lumens placed at positions of 3 o'clock and 9 o'clock within the inner core123. Other quantities of lumens127and positions are contemplated for various applications and situations. The inner core123may be rotated within the outer shell125of the catheter apparatus121by turning or otherwise manipulating a rotator129at a proximate end131of the catheter apparatus121. The rotator129may be coupled133or otherwise connected to the inner core123. One or more guidewires135may be connected to one or more hubs137at the proximate end131of the catheter apparatus121. The one or more guidewires may extend from a distal end139of the catheter apparatus121.

A rotatable inner core123of catheter apparatus121may be used in conjunction with the various balloon configurations described above. For example, if constructed with a non-longitudinal stabilizing balloon, the shape of the distal tip balloon may be circumferential, i.e., doughnut-shaped.

FIG. 6Ashows an embodiment of the present invention with a single stabilizing balloon143and a deflecting tip145on a catheter apparatus141. The single stabilizing balloon143may be used in conjunction with a deflectable distal catheter tip145for eccentric placement of one or more guidewires147. The one or more guidewires147may be passed through one or more hubs149at a proximate end151of the catheter apparatus141.FIG. 6Bshows a cross section of the catheter apparatus141. One or more lumens153may pass through a shaft155. An inflation port157may allow inflation and/or deflation of the stabilizing balloon143. The deflecting tip145may be located at various angles depending on the particular situation.

Catheter apparatus shafts23,59,87,117,12, and155may be constructed with either a circular, oval, or rectangular shape. Other shapes are possible depending on particular uses.

FIG. 7Ashows an embodiment of the present invention with an expansible portion159at a distal tip161of a catheter apparatus163. The expansible portion159may be a mesh or other similar configuration as described above. The expansible portion159may be expanded by retracting a retracting sheath165away from the distal tip161of the catheter apparatus163. The expansible portion159may be expanded into contact with a wall of a vasculature.

FIG. 7Bshows a detail of the catheter apparatus163. A central core167may contain one or more guidewire lumens169. The central core167may or may not be expandable. The central core167may be rotatable to allow one or more guidewires169to probe various sections of a fibrous cap. One or more hubs171at the proximate end173of the catheter apparatus163may allow passage of the one or more guidewires169.

FIG. 8Ashows an embodiment of the present invention with an expansible portion175at a distal tip177of a catheter apparatus179. The expansible portion175may be a mesh or other similar configuration as described above. The expansible portion175may be expanded by retracting a retracting sheath181away from the distal tip177of the catheter apparatus179. The expansible portion175may be expanded into contact with a wall of a vasculature. One or more hubs185at the proximate end187of the catheter apparatus179may allow passage of the one or more guidewires189.

FIG. 8Bshows a detail of the catheter apparatus179. One or more guidewire lumens183may be formed of extruded plastic or similar materials. The figures generally illustrate three guidewire lumens183, but other numbers and configurations may be desirable depending on particular uses. The one or more guidewire lumens183may have shape-memory alloys or other similar materials integrated into, surrounding or within the structure of the one or more guidewire lumens183. Preferably, the one or more guidewire lumens183may self-expand upon retraction of the retraction sheath181such that ends182of the one or more guidewire lumens are spaced apart and approximately halfway between the center point and the inner surface of a vasculature. The one or more guidewire lumens183may be configured to expand into various predetermined positions and configurations depending on particular applications. For example,FIG. 8Bshows a triangular configuration for the guidewire lumens183. Other configurations are possible using three guidewire lumens183. Furthermore, different numbers of guidewire lumens may be used in various configurations.

Alternatively, the one or more guidewire lumens183may be coupled to an inner surface of the expansible portion175. The one or more guidewire lumens183may be adhered or integrally molded to the inner surface of the expansible portion175.

Expansion of the expansible portion175may cause the one or more guidewire lumens183to separate via a self-expanding shape-memory material. Alternatively, the one or more guidewire lumens183may not be coupled to the expansible portion175but may instead be positioned within the internal volume of the expansible section175to allow probing of a fibrous cap. Additionally, a self-expanding polymer may fill the expansible portion175. In an initial configuration the self-expanding polymer may be in a compressed state. As the expansible portion175is released from the retracting sheath181, the self-expanding polymer may expand as well. The one or more guidewire lumens183may be embedded in the self-expanding polymer and may be moved into a desired position by the expansion of the self-expanding polymer. The self-expanding polymer may expand by absorbing moisture or blood from within the vasculature or through other expansion mechanisms. The self-expanding polymer may then be removed after a procedure.

FIG. 8Cillustrates the operation of the catheter apparatus179ofFIG. 8AandFIG. 8B. Similar operational procedures may be used for other embodiments described herein. Step1ofFIG. 8Cshows the catheter apparatus179in an initial state with a retractable outside sheath181moved as far as possible distally from a guidewire lumen tube191. Steps2-7show incremental stages of retraction of the retractable outside sheath181. As the retractable outside sheath181is retracted back over the guidewire lumen tube191, the expansible portion175is incrementally exposed and allowed to expand. As the expansible portion175expands the one or more guidewire lumens183separate and are held in a desired position by the shape-memory alloy materials or by coupling to the expansible portion175. Step7shows the expansible portion175in a fully deployed state. The end view ofFIG. 8Cshows the one or more guidewire lumens183in the fully deployed state. Step8shows a guidewire189inserted through a guidewire lumen183.FIG. 8Dillustrates the operation of the catheter apparatus179as shown inFIG. 8Cwithin a vasculature184with an occlusion186.

FIG. 9Ashows an embodiment of the present invention with one or more inflatable devices193surrounding one or more guidewire lumens195within an expansible portion197of a catheter apparatus199. The expansible portion197may be a mesh or other similar configuration as described above. The expansible portion197may be expanded by retracting a retracting sheath201away from a distal tip203of the catheter apparatus199. The expansible portion197may be expanded into contact with a wall of a vasculature. The expansible portion197may be omitted as shown inFIG. 9B.

The inflatable devices193may initially be in a deflated condition during insertion and positioning of the catheter. The inflatable devices193preferably are balloons, but may be any other expansible type of device. The balloons may surround the outer surface of the one or more guidewire lumens195. The balloons may be cylindrical or other shapes to position the one or more guidewire lumens195within the expansible portion175. The inflatable devices193may include one balloon for each guidewire lumen195or one balloon may correspond to several guidewire lumens195. For example, a single inflatable device193may be inflated to separate all of the guidewire lumens195. Alternatively, two separate inflatable devices193may be used to separate three or more guidewire lumens. The inflatable devices193may be bifurcated or trifurcated depending on the number of guidewire lumens195and the particular application. The expansible sheath197may assist in containing multiple, separate inflatable devices193, but may not be essential to the operation of the present invention.

One or more ports (not shown) may allow inflation or one or more of the inflatable devices193depending on the number of separate inflatable devices193. For example, one port may be used to inflate one inflatable device193. Alternatively, if two or more separate inflatable devices193are present, then two or more ports may be used to inflate and deflate the inflatable devices193serially or in parallel depending on a particular use or condition. Different numbers and combinations of inflatable devices and ports may be possible. Inflation of various combinations of inflatable devices193with various numbers and configurations of ports may allow for probing of a fibrous cap. If ends of the one or more guidewire lumens195or the inflatable devices193themselves are marked, a user may inflate specific inflatable devices193but not others to more accurately interrogate an occlusion. Each of the inflatable devices193may be inflated into contact with the expanded expansible portion197to secure the position of the one or more guidewire lumens195. Guidewires (not shown) may then be passed through the one or more guidewire lumens195. The inflatable devices193may be deflated prior to withdrawing the catheter apparatus199.

As shown inFIG. 9Ban embodiment of the present invention may include the inflatable devices193without the expansible portion197, as shown inFIG. 9A. The inflatable devices193may be exposed by withdrawing the retracting sheath201. Particularly if the inflatable devices193are unitary, the expansible portion197may not be needed. However, even if the inflatable devices193are separate the expansible portion197may be omitted.

Step1ofFIG. 9Bshows the catheter apparatus199in an initial state with a retractable outside sheath201moved as far as possible distally from a guidewire lumen tube205. Steps2-4show incremental stages of retraction of the retractable outside sheath201to expose the one or more guidewire lumens195with corresponding inflatable devices193. Steps5-6show incremental stages of inflation of the inflatable devices193into a final position with a vasculature209with an occlusion211. Step7shows the catheter apparatus199in a fully deployed state. Step8shows a guidewire207inserted through a guidewire lumen195.

FIG. 10illustrates operation of a catheter apparatus213that may include shape-memory materials integrated with the one or more guidewire lumens217. Preferably, the one or more guidewire lumens217may be constructed out of extruded plastic or other similar materials. Shape-memory or other expansible materials may be integrated into, surround, be contained within or reinforce the one or more guidewire lumens217.

Step1ofFIG. 10shows the catheter apparatus213in an initial state with a retractable outside sheath215moved as far as possible distally from a guidewire lumen tube215. The one or more guidewire lumens217may be exposed by withdrawing the retracting sheath215from the distal end of a catheter apparatus213as shown in Steps2-6. The one or more guidewire lumens217may then assume a final spaced or relaxed configuration as shown in Step7. The guidewire lumens may move outward relative to one another a desired distance and/or into contact with inner walls of a vasculature219with an occlusion221. A guidewire223may then be threaded through the one or more guidewire lumens217as shown in Step8. After completion of a procedure, the retracting sheath215may be advanced towards the distal end of the catheter apparatus to compress the one or more guidewire lumens217into a compact arrangement for removal from the vasculature219. Alternatively, the one or more guidewire lumens217may be withdrawn into the distal end of the retracting sheath215before removal from the vasculature219.

FIG. 11illustrates operation of a catheter apparatus225with expansible devices227surrounding one or more guidewire lumens229. Preferably, the expansible devices227are sponges or other materials that expand within the vasculature without input from a user. Each guidewire lumen229may have a separate expansible device227or multiple guidewire lumens may be incorporated into one expansible device227.

Step1ofFIG. 11shows the catheter apparatus225in an initial state with a retractable outside sheath231moved as far as possible distally from a guidewire lumen tube233. The one or more guidewire lumens229may be exposed by withdrawing the retracting sheath231from the distal end of a catheter apparatus225as shown in Steps2-6. As the retracting sheath231is withdrawn from the expansible devices227, the expansible devices227begin to expand. If the expansible devices227are sponges, the expansible devices227may absorb moisture from the vasculature to increase in volume. The one or more guidewire lumens229may then assume a final expanded configuration as shown in Step7. The guidewire lumens229embedded with the expansible devices227may move outward relative to one another a desired distance and/or into contact with inner walls of a vasculature233with an occlusion235. A guidewire237may then be threaded through the one or more guidewire lumens229as shown in Step8. After completion of a procedure, the retracting sheath231may be advanced towards the distal end of the catheter apparatus225to compress the one or more guidewire lumens229into a compact arrangement for removal from the vasculature233. Alternatively, the one or more guidewire lumens229may be withdrawn into the distal end of the retracting sheath231before removal from the vasculature233. Movement of the retracting sheath231may compress the expansible devices227into a position suitable for removal from the vasculature233. If the expansible devices227are sponges, the compression may force moisture out of the sponges.

Generally, after crossing a chronic total occlusion with a guidewire, the catheter apparatus may be resheathed and removed from the vasculature. The guidewire may be left in position.

One or more guidewires preferably remain in or near the longitudinal axis of the corresponding support catheter lumen. This positioning of the one or more guidewires may optimize the force of the one or more guidewires when engaged with the fibrous cap of the chronic total occlusion. Multiple eccentrically located guidewire lumens may improve the chance of success in passing one or more guidewires through a chronic total occlusion. The mass of the multi-lumen support catheter may provide additional support for the guidewire and prevents off-axis, i.e., lateral, displacement of portions of the one or more guidewires located in the guide catheter and in the vasculature. Eccentric distribution of the one or more guidewire lumens may allow engagement of multiple, eccentric sections of the fibrous cap. Embodiments of the present invention may permit simultaneous placement of multiple guidewires. Multiple guidewires may enhance available techniques such as “parallel guidewire” and “see-saw” wire.

FIG. 12Ashows a catheter apparatus241with guidewire lumens243,245,247passing through loops249,251,253,255,257,259. The number and configuration of the loops or guidewire lumens243,245,247may be variable. Alternative numbers and configurations are possible. Guidewire lumens243,245,247may be guided into a predetermined position during expansion of an expansible support structure261by threading the guidewire lumens243,245,247through the inwardly projecting loops249,251,253,255,257,259. Loops249,251,253,255,257,259may be coupled to the expansible support structure261.FIGS. 12A-12Cillustrate an embodiment of the present invention where each guidewire lumen243,245,247may pass through two loops249,251,253,255,257,259. Alternative embodiments may only use one loop for each guidewire lumen. Still other alternative embodiments may use three or more loops for each guidewire lumen. The operation of the loops and guidewire lumens inFIGS. 12A-12Care illustrative of the alternative embodiments. The guidewire lumens243,245,247are guided into position by passing through the loops249,251,253,255,257,259. The expansible support structure261may be coupled to a main multi-lumen shaft263by any conventional means such as adhesive, welding, etc. In the current embodiment of the invention, three guidewire lumens243,245,247are shown, but other numbers and configurations of lumens may be provided. A sheath265may hold the expansible support structure261in a compressed state prior to deployment of the expansible support structure261.

FIG. 12Bshows a flat projection of the expansible support structure261with loops249,251,253,255,257,259.FIGS. 12A-12Cshow a five closed-cell configuration. Embodiments of the present invention may include different quantities of closed-cells depending on desired applications.FIG. 12Bshows a first closed cell265, a first connector region267, a second closed cell269, a second connector region271, a third closed cell273, a third connector region275, a fourth closed cell277, a fourth connector region279, and a fifth closed cell281. InFIG. 12B, the first closed cell265may be at a distal end of the catheter apparatus241and the fifth closed cell281may located towards a proximal end of the catheter apparatus241. In each closed cell, struts283may form a zigzag pattern to support the catheter apparatus241. Connectors285residing in the first connector region267may connect the first closed cell265to the second closed cell269by linking strut intersections287on the first closed cell267with strut intersections289on the second closed cell271. Connectors285may be thinner than struts283and the angular relationship between struts283and connectors285may change during expansion and compression of the expansible support structure261. Similar structures and interactions may be found in and between the remaining closed cells.

Loops249,251,253,255,257,259may be located at strut intersections291. Loops249,251,253,255,257,259may be coupled to the strut intersections291by loop supports293. Loop supports293may be tapered to reduce stress on the apparatus. Struts283may also be tapered to reduce stress on the apparatus. The loop supports293may be positioned at other locations along the struts283or connectors285if desired. Loops249,251,253,255,257,259and inner shape cutouts may be circular, oval, oblong or any additional shapes to allow the guidewire lumens243,245,247to slide within the loops249,251,253,255,257,259. Shapes other than circles may be beneficial when the loops249,251,253,255,257,259lie at an angle other than perpendicular to the cylindrical plane of the expansible support structure261. Loops249,251,253,255,257,259may be shaped to correspond to guidewire lumens243,245,247and allow the guidewire lumens243,245,247to slide through the loop openings.

Each guidewire lumen243,245,247may pass through two loops in the embodiment ofFIGS. 12A-12C. For example, guidewire lumen243may pass through loops249and251, guidewire lumen245may pass through loops253and255, and guidewire lumen247may pass through loops257and259. Passing the guidewire lumens243,245,247through the loops249,251,253,255,257,259may position the guidewire lumens243,245,247in a desired position within the expansible support structure261. As indicated above, other numbers and configurations of loops are possible. To prevent twisting and damage to the guidewire lumens243,245,247, the loops249,251,253,255,257,259for each guidewire lumen are preferably located on every other closed cell. As shown inFIG. 12B, the loops249,251,253,255,257,259are located on the first closed cell265and the third closed cell273. The loops249,251,253,255,257,259may also be located on, for example, the second closed cell269and the fourth closed cell277. If additional loops are present, then the loops may be located on closed cells separated by one closed cell. This alternating structure may prevent twisting during expansion and compression of the expansible support structure261that may damage or misalign the guidewire lumens243,245,247. Preferably, no loops249,251,253,255,257,259may be located on the fifth or proximal closed cell281. The fifth closed cell281may be adhered to the main tri-lumen shaft263. Thus, the fifth closed cell281may not fully expand during expansion of the expansible support structure261and may not be appropriate for holding loops249,251,253,255,257,259. Similarly, the fourth closed cell277may not fully expand and may also not be suitable for holding loops.

The expansible support structure261, the guidewire lumens243,245,247, and the loops249,251,253,255,257,259may initially be in a compressed state within a sheath265as described in previous embodiments. The sheath265may hold the expansible support structure261in a compressed state. The sheath265may include a radiopaque marker at a distal end of the sheath265or another known location along the sheath265. The radiopaque marker may provide an indication of how much of the expansible support structure261is covered by the sheath265. This may allow for partial withdrawal of the sheath265.

The expansible support structure261may be made of nitinol or another shape-memory material. The loop connectors293may also be made of nitinol or another shape-memory material. The loop connectors293may be set to project inwardly from the cylindrical plane of the expansible support structure261at a given angle. The angle may be any angle, but is preferably approximately 30 degrees inward from the cylindrical plane. The angle or the length of the loop connectors293or both may be varied to create various positions of the guidewire lumens243,245,247within the expansible support structure261. The loops249,251corresponding to a guidewire lumen243may project in opposite directions, for example, loop249may project in a distal direction, and loop251may project in a proximal direction.

When the sheath265is withdrawn from around the expansible support structure261, the expansible support structure261may expand to an expanded state. The sheath265may be partially or completely withdrawn from the expansible support structure261. During expansion of the expansible support structure261, the loops249,251,253,255,257,259may project inward from the cylindrical plane of the expansible support structure261to hold the guidewire lumens243,245,247in a predetermined position within the expansible support structure261. The guidewire lumens243,245,247may remain within the loops249,251,253,255,257,259during expansion and compression of the expansible support structure261. Also during expansion, the angle of the connectors285relative to the closed cells may change. Placing the loops249,251,253,255,257,259on closed cells separated by one closed cell may keep the guidewire lumens243,245,247from twisting. As the expansible support structure261expands, the guidewire lumens243,245,247may diverge into predetermined positions. The expanded catheter apparatus241may not block the vasculature.

Upon completion of a procedure, the expansible support structure261may be compressed and withdrawn from the vasculature. The sheath265may be slid distally over the expansible support structure261. Preferably, no parts of the catheter apparatus241extend outside of the cylindrical plane of the compressed expansible support structure261in the compressed state to facilitate withdrawal of the catheter apparatus241.

FIG. 13shows another loop embodiment of an expansible structure295. In contrast to the loop embodiment241ofFIGS. 12A-12C, the loop embodiment of the expansible structure295ofFIG. 13may have loops297,299,301,303,305,307attached on any of closed cell309,311,313,315. The operation of the apparatus of the loop embodiment of the expansible structure295is similar to the operation of the loop embodiment241ofFIGS. 12A-12C.

To prevent twisting and damage to guidewire lumens243,245,247, connecting members317may couple connection points319of struts321on a closed cell, such as309, to connection points323of struts321on an adjacent closed cell, such as311. The connection points319,323are preferably both distal or both proximal relative to the distal end of the catheter apparatus295. The number and configuration of the connecting members317may be variable. The connecting members317may have an upward bend325and a downward bend327. The bends325,327prevent twisting and damage to the guidewire lumens243,245,247during expansion and contraction of the expansible structure295. During expansion and contraction of the expansible structure295, the upward bend325and the downward bend327cancel and lateral movement of the loops297,299,301,303,305,307.

The connecting members317of the expansible structure295may allow loops on each closed cell309,311,313,315. Loops297,299,301,303,305,307do not need to be on every other closed cell309,311,313,315. The embodiment ofFIG. 13may provide for flexibility of the expansible structure295and may facilitate expansion and contraction during deployment and removal.

The invention also includes embodiments of a catheter apparatus having translating lumens. In particular, one or more smaller lumen catheters pass through the lumen of the catheter apparatus. These lumen catheters, in various quantities, may be individually, jointly, or a combination thereof movable such that the lumen catheters are capable of telescoping. For example, the lumen catheters can be advanced individually or collectively beyond the distal end of the catheter apparatus. The lumen catheters can be advanced and retracted as desired in an effort to cross a lesion, for example. The lumen catheters are configured to allow passage of one or more guidewires. Any of the lumens of any of the catheter embodiments above may be configured to allow passage of these lumen catheters. Thus, the translating lumen catheters may be used in any of the embodiments described above.

The lumen catheters may be shafts configured for passing over the guidewire. In certain embodiments, the lumen catheters may be constructed as shafts with either a circular, oval, or rectangular shape. Other shapes are possible depending on particular uses. Furthermore, each lumen catheter may be individually movable and advanceable beyond the distal end of the catheter apparatus as well as retractable into the catheter apparatus. The lumen catheters may be capable of extending beyond the distal end of the catheter apparatus and retracting into the catheter apparatus. Each of the lumen catheters may be capable of being advanceable and rectractable, for example, approximately 1 to 3 inches, beyond the distal end of the shaft of the catheter apparatus. In one embodiment, an actuator may control movement of the one or more lumen catheters.

This embodiment may include a catheter apparatus including an outer shaft (such as a sheath) having a lumen, a main catheter shaft having a lumen, one or more lumen catheters configured for passing over one or more guidewires and a scaffold structure whereby the scaffold structure is attached to the inner shaft, and whereby the inner shaft and one or more lumen catheters telescope independently of each other. The scaffold may be configured to be non-occluding, allowing blood to flow through. Features of the present invention also include expansion or activation of a distal tip for creating a scaffold structure. In certain embodiments, the outer shaft (e.g. sheath), main catheter shaft and lumen catheters may be slideably operable independently of each other.

The lumen catheters may advance and/or retract in any combination of patterns and/or in unison. The movement may be controlled on an individual lumen catheter basis or movement relative to other, one or more of the other lumen catheters and/or the catheter. Thus, the lumen catheters may be used to attack an occlusion at more than one position. For example, in one embodiment, two lumen catheters may be individually advanced to attack an occlusion at two different positions.

FIG. 14A-Dshow catheter335having lumen catheters337,339and341and its operation. The lumen catheters337,339and341pass through one or more lumens in catheter335. The lumen catheters337,339and341may be movable. Thus, lumen catheters337,339and341may be capable of advancing beyond the distal end of the catheter apparatus and capable of retracting into the catheter apparatus. The lumen catheters may be individually or jointly movable. The lumen catheters may also be operably linked to an actuator. Operation of the actuator may result in advancement/retraction of one or more lumen catheters. The actuator may be configured so that in mode one more the lumens move jointly and while moving individually (separately) in another mode. In certain embodiments, the lumen catheters may be directly attached to the actuator.

FIG. 14Ashows the lumen catheters337,339and341in their unextended position inside the distal end of catheter335. In that position, the distal end of the lumen catheters337,339and341is approximately flush with the distal end of catheter335. Catheter335may be configured to be a hollow tube. Alternatively, catheter335may be a solid tube with a lumen for each lumen catheter337,339, and341. The lumens may be distributed approximately equidistant from each other.FIG. 14Bshows the telescoping of lumen catheter337. As shown inFIG. 14B, lumen catheter337advances from the distal end of catheter335. Lumen catheters339and341may remain in their retracted position or they may telescope jointly or individually.FIG. 14Cshows lumen catheter341in its extended position. In certain embodiments, lumen catheter341may extend between about 1 and about 3 inches beyond the distal end of the catheter335.FIG. 14Dshows lumen catheters337,339, and341in their extended position telescoping from the distal end of the catheter335. The lumen catheters337,339and341may be configured to allow passage of one or more guidewire through each lumen catheter.

FIG. 14Eillustrates operation a catheter apparatus335with lumen catheters337and339. The lumen catheters337and339may be jointly or separately movable. An actuator (not shown) may control movement of the lumen catheters337and339. The lumen catheters337and339are configured for passage of one or more guidewires. While only two lumen catheters are shown, it should be understood that the number of lumen catheters may vary. The lumen catheters have a lumen therethrough. A guidewire, such as guidewire340, may pass through the lumen of the lumen catheter.

Step1ofFIG. 14Eshows the catheter apparatus335in an initial state with optional retractable outside sheath336covering the distal end of the catheter apparatus335. It should be understood that in alternate embodiments, catheter335does not have outside sheath336. The distal end of the catheter apparatus335may be exposed by withdrawing the retracting sheath from the distal end of the catheter apparatus as shown in Step2. As the catheter apparatus is positioned, lumen catheter337and339are individually advanced and guidewires338and340may be advanced beyond the distal end of the lumen catheters. The one or more lumen catheters337and339may then assume a final spaced or relaxed configuration. The one or more lumen catheters337and339may move outward relative to one another a desired distance and/or into contact with inner walls of a vasculature with an occlusion340. The lumen catheters337and339may assume a final spaced or relaxed configuration as shown in Step7. As shown in steps2to7, the guidewires are still inside the lumen catheter337and339. A guidewire340may then be threaded through the one or more lumen catheters (e.g. lumen catheter339) as shown in Step8to pass through occlusion342. After completion of a procedure, the retracting sheath336may be advanced towards the distal end of the catheter apparatus to compress the one or more guidewire lumen catheters337and339into a compact arrangement for removal from the vasculature. Alternatively, the one or more lumen catheters337and339may be withdrawn into the distal end of the retracting sheath336before removal from the vasculature.

The guidewires can be advanced regardless of the position of the lumen catheters. The guidewires338and340of the catheter apparatus may be moved into closer contact with the occlusion342. In one embodiment, the guidewires are advanced when the one or more lumen catheters337and339assume a final spaced or relaxed configuration. The guidewires338and340may move outward relative to one another a desired distance and/or into contact with inner walls of a vasculature with an occlusion340. In one embodiment, the guidewires338and340may be advanced before the one or more lumen catheters337and339are in contact with a vasculature. In another embodiment, the guidewires338and340may not be advanced until the one or more lumen catheters337and339are in contact with a vasculature.

The lumen catheters337,339and341may be surrounded by an expandable support structure. In one embodiment, a single expandable support structure may surround all of the lumen catheters. One or more expandable support structures are contemplated. Thus, in certain embodiment, each of the lumen catheters may be surrounded by an expandable support structure that only surrounds that lumen catheter.

The expansible support structure may be attached to one or more of the lumen catheters such that advancement of the lumen catheters results in expansion of the expansible support structure. Any of the expansible support structures described herein (such as e.g. scaffolds) may be used. The lumen catheters may also be operably linked to an actuator. The actuator may be configured so that in one embodiment one or more the lumens are capable of moving jointly in one mode, capable of moving individually (separately) in another mode and/or any combination of individual and joint movement. In certain embodiments, the lumens may be directly attached to an actuator.

FIGS. 15A-Cshow the distal end of a catheter343having lumen catheters345,347and349and expansible support structure351. The expansible support structure351surrounds the lumen catheters345,347, and349. The expansible support structure may surround all of the lumen catheters together. The expansible support structure may be retractable into catheter343, as described in more detail above. Alternatively, a sheath as described above may cover the expansible support structure351. The catheter343may be a hollow tube, as described in more detail above. Alternatively, catheter343may be a solid tube with at least a lumen for each of the lumen catheters.

FIG. 15Ashows the distal end of a catheter343(not shown) having lumen catheters345,347,349, and expansible support structure351with the expansible support structure in its expanded state. Any number of lumen catheters may be used. Each lumen catheter345,347, and349has a lumen354extending therethrough and the lumen is configured for passing a guidewire. Guidewire355is shown passing through lumen catheter347. The guidewire355may also be advanceable through the lumen catheter347. Alternatively, each lumen catheter may have one or more lumen provided through each lumen catheter. The expansible support structure351may have one or more loops353. Each of the lumen catheters may be in held in position by the one or more loops353. The at least one of the one or more loops353may be located towards the distal end of expansible support structure351with a lumen catheter passing therethough. The lumen catheters345,347and349may be individually or jointly moveable. In one embodiment, the lumen catheters345,347and349may telescope beyond the distal end of the expansible support structure351. The distal end of lumen catheters345,347and349may pass through loops353on the distal end of expansible support structure351. The distal end of lumen catheter such as e.g. lumen catheter357may be configured to be advanceable beyond the distal of expansible support structure351.

FIG. 15Bis a distal end view of catheter343with lumen catheters345,347, and349. Each of the lumen catheters345,347, and349has one or more lumens through which guidewires355may pass. Expansible support structure351is shown surrounding lumen catheter345,347, and349. As shown inFIG. 15C, catheter has one lumen configured for passage of each of the lumen catheters.

FIG. 15Cillustrates the operation of catheter343ofFIG. 15AandFIG. 15B. In particular, this figure illustrates how in certain embodiments of the invention illustrate how the guidewires advance. This figure also illustrates how the telescoping lumen catheters serve to follow the guidewire and may provide support to the guidewire. Similar operational procedures may be used for other embodiments described herein. Step1ofFIG. 15Cshows catheter343with optional retractable outside sheath356(not shown) moved back distally from the catheter343such that expansible scaffold351is partially exposed. Steps2to4show further incremental stages of retraction of the retractable outside sheath356. As the retractable outside sheath356is retracted back over the catheter343, the expansible support structure351, which surrounds lumen catheters345,347, and349, is incrementally exposed and allowed to expand. As the expansible support structure351expands the lumen catheters345,347and349separate and are held in a desired position by the shape-memory allow materials or by coupling to the expansible portion357. Step4shows the expansible support structure351in a fully deployed state. Steps11and12show lumen catheters345,347and349with the expansible support structure351in a fully deployed state. At any stage of the expansion, the lumen catheters345,347and349may be advanced to telescope beyond the distal end of the expansible support structure351or retracted. Thus, for example, as shown in Steps6to12ofFIG. 15C, lumen catheter347may be advanced to telescope beyond the distal end of expansible support structure351or retracted. Furthermore, guidewire355may also be advanced to telescope and/or retracted at any stage of the expansion. Thus, as shown in steps8to12, guidewire355may be advanced beyond the distal end of lumen catheter347.

In another embodiment of a catheter apparatus according to the invention, the one or more lumen catheters surround the main catheter shaft rather than passing through a lumen in the main catheter shaft. The scaffold is disposed on or attached to towards the distal of the catheter shaft. The main catheter shaft may have one or more lumens. Alternatively, the main catheter shaft may not have a lumen.FIG. 16Ato C show the distal end of catheter361having main catheter shaft373, expansible scaffold369and lumen catheters363,365, and367. Catheter361may have lumens through which lumen catheters363,365, and367may pass. Alternatively, catheter361may not have a lumen.FIG. 16Ashows lumen catheters363,365, and367of catheter361(not shown). The number and arrangement of lumen catheters can vary depending on the contemplated use. Each of the lumen catheters363,365and367has a lumen through which a guidewire may pass. As shown inFIG. 16A, the lumen catheters363,365, and367may expand outwardly towards the distal end.FIG. 16Aalso shows end views of the distal and proximal end of the lumen catheters363,365, and367including their lumens.FIG. 16Bshows expansible scaffold369in its expanded state. The scaffold369is disposed or attached towards the distal end of main catheter shaft373. The scaffold369may be disposed on or attached to the distal end of main catheter shaft. The scaffold369includes cells375and inward facing loops371. Each cell is approximately hexagonal and has expansible S-shaped (zig-zag) connectors377on two opposing sides of the hexagon. The configuration and arrangement of each cell, including the connectors, may vary. For example, the connectors may be approximatelyFIG. 8shaped. The inward facing loops371are configured for passing over lumen catheters363,365, and367.FIG. 16Balso shows a distal end view of the scaffold369with loops371visible and a proximal end view the main catheter body. As shown inFIG. 16C, main catheter shaft373may be surrounded by lumen catheters363,365and367.FIG. 16Cshows the distal end of catheter361. The distal end view shows lumen catheters363,365and367passing through inward facing loops of scaffold369.FIG. 16Calso shows the proximal end view of catheter361. In the proximal end view, main catheter body373is surrounded by lumen catheters363,365, and367. This embodiment of the device can achieve a lower overall profile and greater flexibility than when the scaffold is attached to the catheter. Furthermore, the configuration of this device allows for additional space for the telescoping lumens to move.

FIG. 17Ais a perspective view of expansible scaffold391in its expanded state, which may be used in a catheter apparatus of the invention. Scaffold391includes cells393. Each cell is approximately hexagonal and has expansible S-shaped (zig-zag) connectors395on two opposing sides of the hexagon. In one embodiment, these S-shaped (zig-zag) connectors are approximately parallel to an axis passing through the center of the scaffold from the distal to the proximal end. The scaffold also includes inward projecting loops397. The loops are configured for passing a lumen catheter. The number and configuration of the loops and cells, including the connectors, may vary.FIG. 17Bshows a flat projection of expansible scaffold391with hexagonal cells393, S-shaped (zig-zag) connectors395and loops397.

FIG. 18Ato C show another embodiment of a catheter apparatus in accordance with the invention. Catheter apparatus399utilizes scaffold391described above. As shown inFIG. 18, catheter apparatus399includes main catheter body405, scaffold391and lumens407,409and411. Lumens407,409and411extend through the main catheter body beyond the distal end of the catheter body. As discussed above, scaffold391includes hexagonal cells393, S-shaped (zig-zag) connectors395and loops397. Lumens407,409and411may pass through loops397. Loops397of the scaffold391may position the lumens407,409and411on the inside of the scaffold391. The catheter apparatus may include sheath401, which has a lumen through which main catheter body405may pass. The distal end of sheath401may have a two parallel longitudinal axes running from opposing sides of the lumen of sheath401. The closer longitudinal axis passes through the distal tip of sheath401and the further longitudinal axis passes through the opposite end of the sheath401. The distal end of the sheath401may be tapered towards the closer longitudinal axis. This configuration aids in tracking of the catheter tip over a guidewire. Alternatively, the distal tip of the sheath401may be tapered, beveled, round or combinations thereof. The sheath401may include position detection marker403towards the distal end of the sheath. The detection marker403may be a radio-opaque marker band. The proximal end of scaffold391is disposed toward or on the distal end of the main catheter body405. The proximal end of the scaffold391may be physically attached to main catheter body405. The proximal end of the scaffold may be held in place by a biologically acceptable glue or a fitting413. When used as part of the apparatus, fitting413slides over the proximal end of the scaffold and holds it in place. As with the other embodiments, this embodiment of the catheter apparatus may be configured to allow passage of translating lumen catheters, which may telescope.

FIG. 18Bshows a cross-sectional view taken at Section A-A inFIG. 18A. This cross section view shows the outer sheath401surrounding the main catheter body405. Lumens407,409and411are also visible. In the center of the lumens is a small wire running the length of the catheter body. This wire prevents the lumen from stretching or compressing while maintaining flexibility. In addition,FIG. 18Cshows an end view of the distal end of catheter apparatus399. The end view shows scaffold391, lumens407,409and411extending beyond main catheter body405and passing through the scaffold397.