Source: http://www.google.es/patents/US8961494
Timestamp: 2017-11-23 11:43:50
Document Index: 181572664

Matched Legal Cases: ['Application No. 60', '§119', 'Application No. 60', '§119', 'Application No. 60', '§119', 'Application No. 60', '§119', 'Application No. 60', '§119', 'art 100']

Patente US8961494 - Endovascular devices and methods for exploiting intramural space - Google Patentes
Devices and methods for the treatment of chronic total occlusions are provided. One disclosed embodiment comprises a method of facilitating treatment via a vascular wall defining a vascular lumen containing an occlusion therein. The method includes inserting an intramural crossing device into the vascular...http://www.google.es/patents/US8961494?utm_source=gb-gplus-sharePatente US8961494 - Endovascular devices and methods for exploiting intramural space
Número de publicación US8961494 B2
Número de solicitud US 13/660,919
También publicado como EP1924315A2, EP1924315A4, US8323261, US9788855, US20070093781, US20130103070, US20150080928, WO2007033052A2, WO2007033052A3
Número de publicación 13660919, 660919, US 8961494 B2, US 8961494B2, US-B2-8961494, US8961494 B2, US8961494B2
Inventores Chad J. Kugler, Robert E. Atkinson, Matthew J. Olson
Citas de patentes (230), Otras citas (5), Clasificaciones (59)
US 8961494 B2
inserting a guidewire or crossing device into the vascular lumen;
positioning a distal portion of the guidewire or crossing device in the vascular wall;
advancing an intravascular device over the guidewire or crossing device, the intravascular device defining a tubular body and a lumen, and having a distal portion including a side port and lateral projections, wherein each of the lateral projections includes a delivery configuration and a deployed configuration, wherein the lateral projections are formed from a single tubular member and are completely external the lumen in both the delivery and the deployed configurations;
positioning the distal portion of the intravascular device in the vascular wall;
directing the lateral projections laterally within the vascular wall such that the lateral projections are in the deployed configuration;
causing the intravascular device to assume an arbitrary one of two possible orientations relative to the vascular lumen, the two possible orientations comprising a first orientation in which the side port is directed toward the vascular lumen and a second orientation in which the side port is directed about 180 degrees away from the vascular lumen;
advancing a distal end of a reentry device through the side port and determining which of the first orientation and the second orientation is the current orientation of the intravascular device; and
advancing the distal end of the reentry device into the vascular lumen if it is determined that the current orientation of the intravascular device is the first orientation.
2. The method of claim 1, wherein an external sheath is provided over the distal portion of the intravascular device and the lateral projections are directed by withdrawal of the sheath relative to the intravascular device.
3. The method of claim 2, wherein an axis defined by the side port is oriented at an approximately right angle to a plane of the lateral projections.
4. The method of claim 1, wherein determining which of the first orientation and the second orientation is the current orientation of the intravascular device comprises viewing the reentry device as it exits the side port using radiographic visualization.
5. The method of claim 1, wherein the lateral projections comprise a plurality of hinged wings configured for lateral expansion within the vascular wall.
6. The method of claim 1, wherein the side port includes an inclined flap.
7. The method of claim 1, wherein advancing the intravascular device over the guidewire or crossing device includes:
introducing the guidewire or crossing device into the lumen of the intravascular device through a distal opening at a distal tip of the intravascular device.
8. The method of claim 7, wherein the distal opening is located distal of the side port.
withdrawing the guidewire or crossing device from the lumen of the intravascular device; and
introducing the reentry device into the lumen of the intravascular device through a proximal opening at a proximal end of the intravascular device.
10. The method of claim 9, wherein the withdrawing the guidewire or crossing device from the lumen of the vascular device step is performed prior to the introducing the reentry device into the lumen of the vascular device step.
11. The method of claim 10, wherein the lumen is devoid of any component between the withdrawing the guidewire or crossing device from the lumen of the vascular device step and the introducing the reentry device into the lumen of the vascular device step.
12. The method of claim 1, wherein the lateral projections are actuatable from a proximal end of the intravascular device.
13. The method of claim 1, wherein the lateral projections are formed as unitary portions of the tubular body.
14. A method of facilitating treatment via a vascular wall defining a vascular lumen containing an occlusion therein, the method comprising:
advancing an intravascular device over the guidewire or crossing device while the distal portion of the guidewire or crossing device is positioned in the vascular wall, the intravascular device defining a tubular body and a lumen, and having a distal portion including a side port and lateral projections, wherein each of the lateral projections includes a delivery configuration and a deployed configuration, wherein the lateral projections are formed from a single tubular member and as unitary portions of the tubular body;
positioning the distal portion of the intravascular device in the vascular wall with the lateral projections in the delivery configuration;
directing the lateral projections laterally within the vascular wall such that the lateral projections are in the deployed configuration; and
advancing a distal end of a reentry device through the side port and into the vascular lumen distal of the occlusion.
15. The method of claim 14, wherein directing the lateral projections laterally orients the side port toward the vascular lumen.
16. The method of claim 14, wherein advancing the intravascular device over the guidewire or crossing device includes:
17. The method of claim 16, wherein the distal opening is located distal of the side port.
19. The method of claim 18, wherein the withdrawing the guidewire or crossing device from the lumen of the vascular device step is performed prior to the introducing the reentry device into the lumen of the vascular device step.
20. The method of claim 19, wherein the lumen is devoid of any component between the withdrawing the guidewire or crossing device from the lumen of the vascular device step and the introducing the reentry device into the lumen of the vascular device step.
This application is a continuation of U.S. application Ser. No. 11/518,430, filed Sep. 11, 2006, now U.S. Pat. No. 8,323,261, which claims the benefit of U.S. Provisional Application No. 60/716,287, filed Sep. 12, 2005, under 35 U.S.C. §119(e). In addition, this application also claims the benefit of U.S. Provisional Application No. 60/717,726, filed Sep. 15, 2005, under 35 U.S.C. §119(e). In addition, the application also claims the benefit of U.S. Provisional Application No. 60/727,819, filed Oct. 18, 2005, under 35 U.S.C. §119(e). In addition, this application also claims the benefit of U.S. Provisional Application No. 60/811,478, filed Jun. 7, 2006, under 35 U.S.C. §119(e). In addition, this application also claims the benefit of U.S. Provisional Application No. 60/839,782, filed Aug. 24, 2006, under 35 U.S.C. §119(e). The entire disclosure of each of the above-referenced applications is incorporated by reference herein.
FIGS. 36A-36G schematically illustrate alternative re-entry device embodiments; and
FIG. 37 is a perspective view of a rotary drive unit for the re-entry devices illustrated in FIGS. 36A-36G.
Generally, the various embodiments described herein exploit the subintimal space in a vascular wall for purposes of facilitating treatment of vascular disease. In the following detailed description, the embodiments have been organized in terms of their particular function: (i) visually defining the vessel wall boundary; (ii) guarding the vessel wall boundary from perforation; (iii) bypassing an occlusion, and (iv) alternative functions. This organizational approach is used for purposes of illustration and explanation, not for purposes of limitation, as some aspects of some embodiments may be utilized for more than one of the stated functions, and many embodiments have alternative functions not specifically stated or reflected by the organizational titles.
With reference to FIGS. 4, 4A and 4B, a deployment device 400 is shown schematically. Deployment device 400 may be used to direct the subintimal device 300 into the subintimal space 130 at entry point 132 and deploy the subintimal device 300 in a helical pattern therein as shown in FIG. 5. The deployment device 400 may take the form of a balloon catheter including catheter shaft 402 and distal balloon 404. Catheter shaft 402 includes an outer tube 406 and an inner tube 408 defining an inflation lumen 410 therebetween for inflation of balloon 404. The inner wire tube 408 defines a guide wire lumen 412 therein for advancement of the device 400 over a guide wire not shown). A delivery tube 414 extends along the outer tube 406 and around the balloon 404 in a helical (or other) pattern. The delivery tube 414 defines a delivery lumen 416 therein for advancement of the subintimal device therethrough. In this particular embodiment, the subintimal device 300 may have a straight configuration in its relaxed state and rely on the helical delivery tube 414 to achieve the desired helical pattern.
Generally, the subintimal devices described herein are designed for intravascular navigation and atraumatic subintimal passage. The subintimal devices 300 may be constructed similar to a guide wire and may include elements to atraumatically pass through the subintimal space. Such atraumatic elements may be employed to minimize damage to arterial wall and to minimize the likelihood of perforation therethrough. Examples of such atraumatic elements 310 are schematically illustrated in FIGS. 7A-7C. The subintimal device may include a ball-shaped tip 310A as shown In FIG. 7A, a hook-shaped or loop-shaped tip 310B as shown in FIG. 76, and/or a bent tip 310C as shown in FIG. 7C. These atraumatic elements distribute axial forces over larger areas of tissue and thereby reduce the chance of vessel perforation. An additional aspect of the bent tip 310C is ability to torsionally direct the tip and control the path of the device through the subintimal space. The ball tip 310A may be formed from a suitable metallic material including but not limited to stainless steel, silver solder, or braze. The ball tip 310A may also be formed from suitable polymeric materials or adhesives including but not limited to polycarbonate, polyethylene or epoxy. Note that the ball tip 310A may be bulbous and larger than the shaft proximal thereto. The loop tip 310B and bent tip 310C may be created during the manufacturing process (for example by heat setting or mechanical deformation) or the tip may be shaped (for example by mechanical deformation) by the physician.
This design may be implemented in planner shown in FIG. 9H. The subintimal device 300 includes a proximal body portion 304 that is formed of a continuous solid metallic tube 940 and a distal body portion 302 that is formed of the same tube with a laser cut coil segment 930, wherein the pattern of the laser cut defines the teeth 932. Suitable materials for the metallic tube include but are not limited to stainless steel and nickel titanium. Alternatively, the coil 930 may be wound from a continuous wire. The wire may have a cross section that for example has been mechanically deformed (stamped) to form the teeth 932 and allow coil engagement.
FIG. 9I shows one example of a laser cut pattern from the circumference of a tube that has been shown in a flat configuration for purposes of illustration. In the pattern shown in FIG. 9I, the teeth 932 are generally trapezoidal and extend orthogonal to the coil turns 930.
FIG. 9J shows an alternative pattern wherein the teeth are generally rectangular (with a clipped corner) with a major (longer) length extending parallel to the axis of the body. The parallel orientation and longer length of the teeth 932 shown in FIG. 9J promote engagement and reduce slippage of adjacent coil turns 930.
FIG. 11A shows an over-the-wire type subintimal device 1100 (or wire support device) having a coiled gear design 930 as described with reference to FIGS. 9G-9I and a thread design 1000 as described with reference to FIGS. 10A-10B. The device 1100 has a hollow core and may be advanced over a guide wire 700. The geared coils 930 provide axial flexibility and torsional rigidity and the external helical threads provide mechanical engagement with the lesion or arterial wall. FIG. 11B shows an over-the-wire type subintimal device 1110 (or wire support device) in longitudinal section, with an inner tube 1112 having a coiled gear design 930, and an outer tube 1114 having a thread design 1000. The inner tube 1112 contains a guide wire lumen capable of accepting a conventional guide wire 700. FIG. 11C shows a partial enlarged view of an alternative inner tube 1112 where a gaps 934 between adjacent coils allow articulation of the inner tube 1112 upon proximal withdrawal of actuation wire 1118. Outer tube 1114 may freely rotate with respect to inner tube 1112 when the inner tube 1112 is in both the straight and actuated positions.
In addition to penetrating the intimal layer, entering the subintimal space, and traversing the occluded segment, the following bypass embodiments generally involve orientation and re-entry into the true lumen. A general approach to the foregoing bypass embodiments is schematically illustrated in FIGS. 14A-14H. A guide wire 700 may be advanced through the proximal segment 112 of the true lumen 116 of the occluded artery to the proximal edge of the total occlusion 120 adjacent the vessel wall 118 as shown in FIG. 14A. By manipulating and directing the guide wire 700 to the proximal edge of the total occlusion 120 toward the wall 118, the guide wire 700 may penetrate the intimal layer 113 and enter the subintimal space 130 between the intima 113 and the media/adventitia 115/117 as shown in FIG. 14B. The manipulating and directing of the guide wire 700 as described above may be performed by using the guide wire alone or by using any of the directing devices described herein. With the guide wire 700 in the subintimal space 130, a subintimal device 1400 may be advanced over the guide wire 700 as shown to FIG. 14C. In the illustrated embodiment, the subintimal device 1400 includes a hollow elongate shaft 1402 and an atraumatic bulbous tip 1404. However, any of the subintimal devices described herein may be employed, particularly the over-the-wire type subintimal devices. As shown in FIG. 14D, the subintimal device 1400 may be further advanced over the guide wire 700 such that the tip 1404 resides in the subintimal space 130. At this procedural stage, the guide wire 700 may be withdrawn, completely removing it from the subintimal device 1400. Further manipulation of the subintimal device 1400 (both axial advancement and radial rotation) allows blunt dissection of the layers defining the subintimal space 130 and advancement of the device 1400 to the distal portion of the total occlusion 120 as shown in FIG. 14E. Penetration of the intimal layer 113 and re-entry into the distal segment 114 of the true lumen 116 distal to the occlusion 120 may be achieved by various means described later in detail, which generally include the steps of orientation toward the center of the true lumen 116 and penetration of the intimal layer 113. For purposes of illustration, not limitation, FIG. 14F shows a shaped re-entry device 1420 having a curled and sharpened tip exiting the lumen of the subintimal device 1400 distal of occlusion 120 and entering the distal segment 114 of the true lumen 116 through the intimal layer 113. With re-entry device 1420 in the distal segment 114 of the true lumen 116, the subintimal device 1400 may be advanced into the true lumen 116 over the re-entry device 1420 as shown in FIG. 14G. The re-entry device 1420 may be withdrawn from the subintimal device 1400 and the guide wire 700 may be advanced in its place as shown in FIG. 14H, after which the subintimal device 1400 may be withdrawn leaving the guide wire 700 in place. As such, the guide wire 700 extends from the proximal segment 112 of the true lumen 116 proximal of the occlusion 120, traverses the occluded segment via the subintimal space 130, and reenters the distal segment 114 of the true lumen 116 distal of the occlusion 120, thus bypassing the total occlusion 120 without exiting the artery. With the guide wire 700 so placed, the subintimal space 130 may be dilated (e.g., by balloon angioplasty or atherectomy) and stented, for example, or otherwise treated using known techniques.
As mentioned above, re-entry into the true lumen from the subintimal space generally involves orientation toward the center of the true lumen and penetration of the intimal layer. Although fluoroscopy is a commonly available visualization tool used during interventional procedures, it only provides two-dimensional images which are typically insufficient, taken alone, to determine the proper direction for penetration from the subintimal space toward the center of the true lumen. As such, those skilled in the art may use visualization tools with greater accuracy or with the ability to show three dimensional data. For example, intravascular ultrasound (BTUS) or magnetic resonance imaging (MRI) may be used to determine the position and direction of true lumen re-entry from the subintimal space. However, such techniques are time consuming, expensive and often impractical, and therefore it would be desirable to facilitate orientation (i.e., direct a re-entry device from the subintimal space toward the true lumen distal of a total occlusion) without the need for such burdensome visualization techniques.
In the following embodiments, detailed examples of devices are described which facilitate one or more of the steps involved in visualizing, perforation guarding, and/or bypassing a total occlusion as generally described previously. These devices may for example: (i) facilitate subintimal device tracking by transmitting sufficient axial force and radial torque (sometimes referred to as push and twist respectively) to enter the subintimal space, delaminate the intima from surrounding tissue layers, and traverse the total occlusion via the subintimal space; (ii) facilitate alignment of the subintimal device within the subintimal space with a favorable orientation for true lumen re-entry distal of the total occlusion; (iii) facilitate advancement of a re-entry element that takes advantage of the subintimal device alignment and orientation to direct itself toward the true lumen; (iv) facilitate penetration of the intimal layer to regain access to the true lumen distal of the total occlusion; and/or (v) facilitate confirmation that true lumen re-entry has been achieved.
The tubular shaft 1702 may be made from suitable polymeric materials such as polyethylene, nylon, or polyether-block-amide (e.g., Pebax™). The tubular shaft 1702 may also have composite structure where the inside layer may have a lubricious polymer such as polyethylene or a fluoropolymer such as PTFE (e.g., Teflon™), the middle layer may have a metallic or polymeric braided structure such as polyester or stainless steel, while the outside layer may also be made of a similar polymeric material. The outside of the subintimal device 1700 may also have a lubricious exterior coating. For example, coatings may include liquid silicone or hydrophilic coating such as hyaluronic acid. The stylet 1703 may be made of suitable metallic materials including but not limited to stainless steel or nickel titanium alloys. The atraumatic tip 1704 may be made of suitable metallic or polymeric materials including, for example, stainless steel, titanium, polycarbonate, or polyether-block-amide (e.g., Pebax™).
As seen in FIGS. 17A and 17B, which are cross sectional views taken along lines A-A and B-B, respectively, in FIG. 17, all ora portion (e.g., distal portion) of the stylet 1703 may interface with a feature 1706 within the tubular shaft 1702 and/or within the atraumatic tip 1704. For example, the tubular shaft 1702 and/or the atraumatic tip 1704 may contain a lumen with a geometric feature 1706 intended to mate or key with distal tip of the stylet 1707 as shown in FIG. 17B. This keying or mating feature 1706 allows torque to be transmitted from the operators hand to the distal tip of the subintimal device through twist of the subintimal device and stylet. For the purpose of illustration, the geometric feature 1706 is shown as a square in cross-section, but it is intended that any geometry other than round may be used to create engagement of the perimeter of the stylet 1703 with the internal lumen of the tubular shaft 1702 and/or atraumatic tip 1704.
With reference to FIG. 21B a compound bend may be achieved by pulling the actuation member 2105 relative to shaft 2102. Pulling the actuation member 2105 may compress segments 2103 thus shortening the subintimal device length along the side of the of the shaft 2102 with mare flexible segment material 2103. A compound bend may be achieved by arranging the flexible segment material 2103 in the desired pattern and/or by using multiple longitudinal members 2105. Alternatively, a compound bend may also be achieved using a single side of flexible segment material 2103 and a single longitudinal member by relying on device interaction with the adventitial layer as described previously.
With reference to FIGS. 22A-22C, another embodiment of a subintimal device 2200 capable of achieving a compound bend is shown schematically. FIG. 22A only shows the distal portion of the subintimal device 2200 for purposes of illustration and clarity. In this embodiment, the tubular shaft of the subintimal device 2200 comprises an inner tube 2201 and an outer tube 2204 (shown cut away), between which is disposed a series of circumferential rings 2202 interconnected by longitudinal members 2203. An atraumatic tip 2207 is connected to the distal end of the shaft, and a central lumen 2206 runs through the device 2200 for the acceptance of a guide wire and/or a reentry device. Suitable materials for the circumferential rings 2202 and longitudinal members 2203 include but are not limited to nickel titanium, stainless steel, or MP35N. The inner tube 2201 and the outer tube 2204 may be made of suitable polymeric materials such as polyethylene, polyether-block-amide (e.g., Pebax™), or nylon. The distal portion of the subintimal device may have a pre-formed curved shape (e.g., compound bend) in its relaxed state as shown in FIG. 22A.
The subintimal device 2200 may be slideably disposed within an external delivery sheath 2205 as shown in FIGS. 22B and 22C. The sheath 2205 may be slightly stiffer then the subintimal device 2200 such that the subintimal device 2200 assumes a straight shape when the sheath 2205 covers the distal portion of the device as shown in FIG. 228, and assumes a curved shape when the sheath 2205 is retracted as shown in FIG. 22A. Upon proximal retraction of the sheath 2205, the subintimal device 2200 may assume a compound bend by virtue of its preformed shape, or it may assume axial curvature by virtue of its preformed shape and radial curvature by virtue of interaction with the adventitia as described previously.
FIGS. 24A-24C show various embodiments of penetrating tips for use on a re-entry device. As mentioned previously, the re-entry device 2310 may comprise a guide wire the like to facilitate penetration through the intimal layer 113 from the subintimal space 130 to the true lumen 116. Alternatively, the tip of the re-entry device 2310 may be designed to enhance penetration through the intimal layer 113, particularly in the case where the intimal layer is diseased. If the intimal layer 113 is diseased, it will likely be tougher than healthy tissue because it may contain soft plaque, fibrous plaque and/or hard calcified plaque. The presence or absence of disease at the intended re-entry site and the nature of the disease may require a re-entry device capable of penetrating the various plaques within a non-homogenous diseased arterial wall. In the event the re-entry site is free from disease or contains relatively soft plaque, a conventional guide wire may be used as a re-entry device. Alternatively, if disease is encountered, the tip configurations illustrated in FIGS. 24A-24C may be employed.
One method of determining if the true arterial lumen has been accessed is by drawing intra-arterial blood from the distal entry point proximally through a lumen within the re-entry device or a lumen within the subintimal device to the proximal end of the device where the presence of blood may be detected. This method takes advantage of the fact that there typically blood in the true lumen distal of the occlusion but there is little to no blood in the subintimal space. Thus, the absence of blood indicates the device is subintimal and the presence of blood indicates the device is in the true lumen. This technique may also be used to indicate perforation of the device out of the artery and into the pericardial space by the presence of pericardial fluid.
FIG. 25 illustrates a re-entry device 2500 that facilitates confirmation of true lumen re-entry. The re-entry device 2500 may be passed through a subintimal device 2300, oriented toward the true lumen 116, and penetrate the intimal layer 113 from the subintimal space 130 to the true lumen 116 as described previously. In this embodiment, the re-entry device 2500 is provided with an internal lumen extending from its proximal end to a distal opening 2502. The proximal end of the re-entry device 2500 is connected to an indicator 2504 which is in turn connected to a vacuum source. The indicator 2504 may be a flow indicator such as a collection vessel where the presence and type of fluid may be visually observed. With the vacuum source generating a negative pressure, entry of the re-entry device 2500 into the true lumen 116 allows blood to flow into the distal opening 2502 and through the internal lumen to the indicator 2504. Alternatively, the vacuum source and indicator may be fluidly attached to the subintimal device where entry of the device into the true lumen results in similar blood flow into the indicator. Alternative indicators 2504 may be employed such as impedance sensors, oxygen sensors, optical sensors etc.
The deployable element may alternatively provide vessel wall protection by indicating when the occlusion crossing device (guide wire, atherectomy device, laser ablation device, and radiofrequency ablation device, etc.) is in close proximity to or in contact with the vessel wall. For example, either the distal end of the deployable element or the distal end of the crossing device may act as a transmitting antenna and the other of the two may act as a receiving antenna. The transmitting antenna may be electrically connected to a radiofrequency (RE) signal generator and the receiving antenna may be connected to an RF signal receiving or detection circuit via a lengthwise insulated and/or shielded lead disposed in each of the devices. As an alternative to RF proximity detection, impedance may be similarly used as an indicator of proximity.
With either an RE or impedance based approach, a relatively weak signal is indicative of the crossing device being further away from the deployable element, for example when the crossing device is in the center of the occluded artery. A relatively stronger signal is indicative of the crossing device being in close proximity to the deployable element, for example within the subintimal space. The physician may use this proximity information to safely and effectively direct the crossing device within the confines of the deployable element and across the total occlusion within the true arterial lumen.
With reference to FIGS. 30C, a tubular cutting device 3020 with a sharpened leading edge may be advanced over the subintimal device 300 and the capture device 3010 to engage and cut the intimal layer 113 with the total occlusion 120 therein. With reference to FIG. 30D, further advancement of the cutting device 3020 cuts and separates the diseased portion including the total occlusion and surrounding intima from the remainder of the artery. Proximal withdrawal of the device from the artery results in removal of the total occlusion and a patent true lumen 116. The occlusion 120 may be removed through the percutaneous intravascular access site or a surgical cut down may be performed to facilitate removal if the occlusion is too large for removal through the percutaneous access site. Alternatively, to reduce the size of the occlusion and thus facilitate removal through the percutaneous access site, a maceration mechanism may be employed to macerate the occlusion prior to removal.
FIGS. 32A-32E illustrate an alternative system for bypassing a total occlusion. With reference to FIG. 32A, a subintimal device 3200 is shown in the deployed configuration. The subintimal device 3200 includes an elastic wire 3210 with a distal form similar to the elastic wire form 2800 described with reference to FIG. 28, except with fewer sinusoidal turns. The subintimal device also includes a crescent-shaped or semi circular delivery shaft 3220 and a retractable constraining sheath 3230. As seen in FIG. 32B, which is a cross-sectional view taken along line A-A in FIG. 32A, the wire 3210 resides in the recess of the semi-circular delivery shaft 3220 over which the constraining sheath 3230 is disposed. As an alternative, the constraining sheath 3230 may be disposed about the wire 3210 only and may reside in the recess of the delivery shaft 3220, provided that the constraining sheath 3230 is sufficiently stiff to at least partially straighten the formed wire 3210. The distal end of the wire 3210 is connected to a blunt tip 3222 of the shaft 3220. The wire 3210 and the semi-circular shaft 3220 may be formed of a resilient metallic material such as nickel titanium, stainless steel, elgiloy, or MP35N, and the sheath 3230 may be formed of a flexible polymeric material such as a polyether-block-amide (e.g., Pebax) lined with PTFE (e.g., Teflon).
As shown in FIG. 32D, with the wire form 3210 deployed in the subintimal space and with the sheath 3230 removed from the shaft 3220, a dual lumen re-entry delivery catheter 3250 may be advance over the shaft 3220. As seen in FIG. 32E, which is a cross-sectional view taken along line A-A in FIG. 321), the delivery catheter 3250 includes a crescent-shaped or semi-circular lumen 3254 that accommodates the shaft 3220 extending there through. The delivery catheter 3250 also includes a circular lumen 3252 that accommodates a re-entry device 3240 extending therethrough. The delivery catheter 3250 may comprise a dual lumen polymeric extrusion such as polyether-block-amid (e.g., Pebax) and the re-entry device 3240 may be the same or similar to the re-entry devices described previously herein.
Alternatively, the delivery catheter 3250 may comprise two coaxial tubes including an elongate inner tube disposed in an elongate outer tube. The inner tube is configured to accommodate a re-entry device. The annular lumen defined between the inner tube and the outer tube is configured to accommodate semicircular delivery shaft 3220. At the distal end of the delivery catheter 3250, the inner tube may be tacked to the inside of the outer tube using a heating forming process where a portion of the outside circumference of the inner tube is thermally fused to the inside circumference of the outer tube thus creating a cross Section similar to that shown in FIG. 32E over the heat formed area Outside the heat formed area the inner and outer tubes may remain coaxial and un-fused.
FIGS. 33A-33E schematically illustrate an embodiment using one or more subintimal guide catheters 3310/3320 to introduce an orienting device 3330. These Figures show a window cut-away in the outer layer of the vascular wall for purposes of illustration. In this embodiment, which is an alternative bypass embodiment in some aspects, a subintimal crossing device 300 with or without a guide wire lumen (shown) and having a bulbous tip 310 (e.g., 0.038 in. diameter olive shaped weld ball) is used to safely cross the subintimal space by blunt dissection as described elsewhere herein.
With the outer sheath 3320 in place and providing a protected path across the occlusion within the subintimal space, an orienting device 3330 may be inserted into the sheath 3320 to the distal end thereof as shown in FIG. 33C. In this Figure, a window cut-away is shown in the distal portion of the outer sheath 3320 for purposes of illustration. FIG. 33C shows the orienting device 3330 in the delivery configuration with the orienting element collapsed and FIG. 33D shows the orienting device 3330 in the deployed configuration with the orienting element expanded.
The side port 3338 is oriented at a right angle to the plane of the orienting element 3336. With this arrangement, the side port 3338 is either directed toward the vascular true lumen 116 or 180 degrees away from the vascular true lumen 116. Radiographic visualization or other techniques as described elsewhere herein may be used to determine if the port 3338 is directed toward or away from the true lumen 116. If the port 3338 is directed away from the true lumen 116, the orienting device may be retracted, rotated 180 degrees, and re-deployed to point the port 3338 toward the true lumen 116. A re-entry device as described elsewhere herein may then he advanced through the lumen of the tubular shaft 3332, through the vascular wall and into the true lumen 116.
As an alternative to orienting device 3330 shown in FIG. 33D, orienting device 3340 shown in FIG. 33E may be employed in substantially the same manner. Orienting device 3340 includes an outer tube 3342 and an inner tube 3344. The outer tube 3342 may be formed of a superelastic metal alloy (e.g., NiTi), and a distal portion of the outer tube 3342 may be cut (e.g., using laser cutting techniques) to form slots to define two wings 3346 that hinge outward in a planar fashion as shown. The inner tube 3344 extends through the lumen of the outer tube 3342 and is attached distally to the distal end of the outer tube 3342. Inner tube 3344 is similar in design and function as tubular shaft 3332, and includes a distal side port 3348 to accommodate a re-entry device as described with reference thereto. Alternatively, a flap port may be used as will be described in more detail hereinafter.
The outer shaft 3410 may comprise, for example, a polymeric tube 3412 that may be reinforced with an embedded braid or wire ribbon. The inner shaft 3420 may comprise a metallic tube 3422 (e.g., NiTi) with a solid tubular proximal segment and a spiral cut 3424 distal segment for added flexibility and torqueability. The distal portion of the inner shaft 3420 may include an inwardly inclined flap 3426. As seen in FIG. 34B(1), the flap 3426 extends into the lumen of the inner shaft 3420 and operates to (1) direct front loaded devices (e.g., re-entry device) out the side port 3425 of the inner shaft 3420 adjacent the orienting element 3440; and (2) direct back loaded devices (e.g., subintimal crossing device or guide wire) down the lumen of the proximal segment 3422 of the inner shaft 3420 while preventing back loaded devices from exiting the side port 3425. A semi-circular slot 3428 may be formed to accommodate the end of the flap 3426 to prevent the edge of the flap 3426 from snagging on devices passing by. The cuts may be formed by laser cutting or the like and the flap may be biased inwardly by heat setting.
With reference to FIGS. 34A and 34E, the orienting element 3440 may comprise a metallic tube (e.g., NiTi) with cuts made to define two wings 3442A and 3442B. In FIG. 34E, the cut pattern of the orienting element 3440 is shown as if the tube were laid flat with dimensions given in inches unless otherwise noted. The cuts are made to define two separate wings 3442A and 3442B, with three hinge points 3443, 3444 and 3445 per wing 3442. The proximal end 3446 of the orienting element 3440 is connected to a flared end of the outer shaft 3410, and the distal end 3448 is connected to the distal end of the inner shaft 3420 and the proximal end of the tubular tip 3450. By contracting the proximal end 3446 toward the distal end 3448, the proximal lunge 3445 and the distal hinge 3443 flex outwardly to extend each wing 3442 outwardly, with the center hinge 3444 at the apex of each wing 3442.
One method of directing the side port toward the true lumen involves taking advantage of the curvature of the heart 100. Generally speaking, the coronary arteries including the left anterior descending artery 110 as shown in FIG. 35A will follow the outside curvature of the bean 100. An orienting device (e.g., 3330, 3340, 3400) inserted into the coronary artery 110 via a guide catheter 200 seated in the ostium of the artery 110 will generally follow the outside curvature of the artery 110 within the subintimal space and across the occlusion 120. In this scenario, as seen in FIG. 35B, the true lumen 116 will lie toward the inside of the curvature of the artery 110 and thus the inside curvature (i.e., concave side) of the orienting device 3400. Thus, the side port of the orienting device 3400 may be directed toward the concave side of the curvature which will predictably direct the side port toward the true lumen 116. Directing the side port in this fashion may be facilitated by using radiographic visualization to view one or more radiopaque markers on the orienting device associated with the side port or a radiopaque device (e.g., guide wire) inserted into the orienting device just as it exits the side port. In addition or as an alternative, the orienting device may be pre-curved such that it naturally orients or “keys” with the curvature of the artery with the side port arranged on the concave side of the pre-curve. In addition or as an alternative, a radiopaque device (e.g., guide wire 700) may be substantially advanced and bunched within the subintimal space via a subintimal device (e.g., crossing device 300 or orienting device 3400) as shown in FIG. 35C such that the radiopaque device extends at least partially circumferentially to assume the curvature of the artery with the true lumen oriented toward the concave side thereof.
With specific reference to FIG. 36A, and to FIG. 36B which is a detailed cross-sectional view of the distal end, re-entry device 3610 includes a distally tapered drive shaft 3612 which may comprise a metallic alloy such as stainless steel or NiTi, for example. The re-entry device 3610 may have a nominal profile of 0.014 inches and a length of 150 cm for coronary applications. The shaft 3612 may have a proximal diameter of 0.014 inches and a distal taper from 0.014 inches to 0.006 to 0.008 inches over approximately 4.0 inches. An abrasive tip 3620 may be connected to the distal end of the shaft 3612 by brazing or welding techniques. The shaft 3612 just proximal of the tip 3620 is configured with sufficient flexibility to allow flexure of the tip 3620 after it penetrates the vascular wall into the true vascular lumen, thus preventing penetration of the opposite vascular wall. The abrasive tip 3620 may comprise metallic alloy tube 3622 such as stainless steel, platinum or platinum-iridium with a weld ball cap 3624. The tube 3622 may have an inside diameter of approximately 0.007 inches and an outside diameter of approximately 0.0105 inches. An abrasive coating such as a 600 grit diamond coating 3626 may be applied to the outer surface of the tube 3622 with a thickness of approximately 0.0015 inches using conventional techniques available from Continental Diamond Tool (New Haven, Ind.).
With reference to FIG. 37, a rotary drive unit 3700 is shown in perspective view. Rotary drive unit 3700 is particularly suited for use with re-entry device 3610 shown in FIGS. 36A-36G, but may be used with other re-entry devices described elsewhere herein, Generally, the rotary drive unit 3700 provides for independent rotation and advancement of a re-entry device, wherein the rotation is provided by a motor and advancement is provided by shortening or lengthening a partial loop of an advancement sleeve that is attached at only one end and may be advanced/retract without moving the motor drive.
US6506178 * 10 Nov 2000 14 Ene 2003 Vascular Architects, Inc. Apparatus and method for crossing a position along a tubular body structure
1 Bolia, Amman, Subintimal Angioplasty: Which Cases to Choose, How to Avoid Pitfalls and Technical Tips, Combined Session: Vascular Surgery and Interventional Radiology, pp. III 8. 1-8.3.
2 Colombo, Antonio et al., Treating Chronic Total Occlusions Using Subintimal Tracking and Reentry: The STAR Technique, Catheterization and Cardiovascular Interventions, vol. 64: 407-411 (2005).
3 International Preliminary Report on Patentability in PCT/US06/35244 dated Mar. 17, 2009.
Clasificación de EE.UU. 604/509, 606/167
Clasificación internacional A61B17/00, A61B17/22, A61M25/04, A61B17/3205, A61M25/10, A61B17/34, A61B17/221, A61M25/09, A61F2/88, A61M25/00, A61B17/32, A61M31/00, A61B17/3207, A61M25/01
Clasificación cooperativa A61B17/3417, A61B17/3415, A61B17/3403, A61B17/3476, A61B2017/3454, A61B2017/3405, A61M25/04, A61B17/32053, A61M2025/105, A61M25/0152, A61M2025/018, A61B2017/320064, A61F2/88, A61M25/003, A61B2017/00252, A61B2017/22077, A61B2017/22094, A61M25/0069, A61M2025/006, A61B17/00008, A61M25/0074, A61M25/0045, A61B2017/22044, A61M25/0082, A61B2017/22034, A61M25/007, A61B2017/003, A61M2025/09191, A61B2017/00455, A61B2017/320004, A61B2017/22095, A61M2025/09175, A61B17/221, A61M25/10, A61B2017/320741, A61B2017/00685, A61B17/22031, A61B17/32075, A61B2017/2212, A61B2017/22038, A61B2017/320044, A61M25/0032, A61B17/320758