1. Field of the Invention
The present invention generally relates to medical devices, and in particular, to catheters which can be used in an emboli containment system. This invention also relates to an apparatus and method for treating occluded vessels in living bodies and more particularly balloon catheters and balloon guide wires for treating occlusions in vessels in human bodies, as for example carotid arteries.
2. Description of the Related Art
Balloon angioplasty, and other transluminal medical treatments, are well-known, and have been proven efficacious in the treatment of stenotic lesions in blood vessels. The application of such medical procedures to certain blood vessels, however, has been limited, due to the risks associated with creation of emboli during the procedure. For example, angioplasty is not the currently preferred treatment for lesions in the carotid artery, because of the possibility of dislodging plaque from the lesion, which can enter the various arterial vessels of the brain and cause permanent brain damage. Instead, surgical procedures are currently used, but these procedures present substantial risks.
One solution to this problem is the use of a multi-catheter emboli containment system, as disclosed in the above-referenced application Ser. No. 08/650,464. As disclosed therein, a treatment chamber within a blood vessel is formed by two occlusion balloons on opposite sides of a stenotic lesion, thereby preventing emboli migration during the treatment procedure. The chamber is created by two occlusion balloon catheters which are slidably disposed with respect to one another.
Emboli containment procedures of this type are advantageous, because they permit the clinician to utilize the benefits of transluminal treatment in a wider variety of blood vessels. However, the procedures require the complex coordination of multiple catheters. Consequently, it is desirable to have catheters which make it easier for the clinician to utilize an emboli containment system. It is also desirable that the catheters used in the emboli containment system have a high degree of flexibility, to navigate tortuous blood vessel networks.
Consequently, there exists a need for improved emboli containment catheters. This is especially true in the context of the “main” catheter, through which other catheters are inserted and controlled to form the emboli containment system. There is also a need for new and improved apparatus and methods which make it possible to treat occluded vessels without endangering the patient.
The application describes and claims a guidewire that has a self-expanding member mounted on a distal extremity thereof. In one aspect, the self-expanding member comprises a braided structure. The braided structure can be formed of a suitable shape memory material, such as a nickel-titanium alloy, that will expand to a predetermined shape. A covering of a suitable material, such as a polymer, in some embodiments extends over the braided structure. Where provided, the covering moves with the braided structure as it expands and as it is compressed.
The present invention advantageously provides as a main catheter an occlusive device adapted for use in a multi-catheter emboli containment system. In one aspect of the present invention, there is provided a catheter, comprising an elongate flexible tubular body having a proximal end and a distal end. The tubular body incorporates a metallic member, which may comprise a braid or a coil. A main lumen and an inflation lumen extend through the tubular body, and are in a side-by-side configuration. The main lumen is sized to receive a therapeutic and/or diagnostic device such as a balloon angioplasty catheter or an atherectomy catheter. The tubular body is provided with a manifold. The manifold has an aspiration port which is in fluid communication with the main lumen. The distal end of the tubular body also has a tip formed of a more flexible material than that used to form the tubular body.
In one preferred embodiment, an inflatable balloon is mounted on the distal end of the tubular body. An inflation port is also provided on the manifold in this embodiment. The inflation port is in fluid communication with the inflation lumen. In this embodiment, the inflatable balloon is formed of a block copolymer of styrene-ethylene-butylene-styrene.
In another preferred embodiment, the metallic braid or coil is formed of a metal selected from the group consisting of 304, 316, or 400 series stainless steel, nitinol, i.e. a nickel titanium, sometimes referred to herein as “Nitinol”, platinum, gold, Elgiloy®, or combinations thereof. Where a metallic braid is used, it may optionally have a braid density at a first point on the tubular body that is greater than the braid density of the metallic braid at a second point on the tubular body by at least 20 picks per inch. Similarly, where a metallic coil is used, it may optionally have a coil density at a first point on the tubular body that is greater than the coil density at a second point on the tubular body.
In another aspect of the present invention, there is provided a catheter comprising an elongate flexible tubular body having a proximal end and a distal end. Alternatively, there may be provided a circular cross-sectional configuration at the proximal end which is continuous with a distal end having a reduced internal and outer tubular body diameters. A first and second lumen extend through the tubular body from the proximal end to the distal end in a side-by-side configuration. The first lumen has a generally circular cross-sectional configuration at the proximal end and a generally oval cross-sectional configuration at the distal end. The second lumen has a diameter no smaller than 0.05 inches, preferably no smaller than 0.08 inches, and is adapted to slidably accommodate a therapeutic or diagnostic device.
In one preferred embodiment, an inflatable balloon is mounted on the distal end of the tubular body. The inflatable balloon is in fluid communication with the first lumen, such that fluid passing through the first lumen may be used to inflate or deflate the inflatable balloon. The second lumen size may vary in certain embodiments, such that in one embodiment, the second lumen has a diameter no smaller than about 0.05 inches, and is preferably no less than 0.080 inches.
In another aspect of the present invention, there is provided a catheter with variable stiffness, comprising a tubular body having a proximal end and a distal end. A metallic braid or metallic coil is within the tubular body. In one embodiment, the proximal end of the tubular body has a lower braid or coil density than the distal end. In another embodiment, the braid or coil density is kept constant along the length of the tubular body, and the tubular body is formed of materials with greater stiffness at the proximal end. In another embodiment, a combination of braids and coils of varying density can be used at various points along the tubular body, to create a catheter tubular body having a more flexible distal end.
In another aspect of the present invention, there is provided a method of making a catheter tubular body. The method comprises providing a first polymeric tube formed of a first material having a first melting point. The first polymeric tube is then inserted into a second polymeric tube to form a combined tube. The second polymeric tube is formed of a second material having a second melting point which is less than the first melting point. The combined tube is then placed adjacent to a third tube. The third tube is formed in part of the second material. The tubes are then heated to a temperature greater than the second melting point but less than the first melting point, such that the combined tube melt fuses with third tube to form a catheter tubular body having two lumen extending therethrough in a side-by-side configuration. The first material may be selected from the group comprising polyimide, polyamide, PET, and polyetheretherketone (referred to herein as “PEEK”), blends thereof and the second material may be selected from the group comprising PEBAX®, polyethylene, nylon, or HYTREL® or blends thereof. Preferably, the temperature of the heating step is from about 250° to 600° F. It is also preferred that the third tube incorporate a metallic member, such as a braid or coil.
In general, it is an objection of the present invention to provide an apparatus or an assembly and method which can be used with approved diagnostic and therapeutic devices while minimizing the opportunities for emboli to migrate downstream.
Another object of the present invention to provide an apparatus or assembly and method of the above character which makes it possible to perform therapeutic procedures without using perfusion.
Another object of the invention is to provide an apparatus or assembly and method of the above character in which the proximal balloon utilized is a balloon carried by a guide wire.
Another object of the invention is to provide an apparatus or assembly and method of the above characters in which the inflation fitting carried by the proximal extremity of the balloon-on-a-wire is removable so that catheters can be slid over the wire without removal of the wire from the site in which it is disposed.
Another object of the present invention is to provide an apparatus or assembly and method for treating occluded vessels of the above character which makes it possible to prevent downstream flow of debris or emboli.
Another object of the invention is to provide an apparatus and method which makes it possible to reverse the flow of blood in an occluded vessel during the time that a stenosis is being crossed.
Another object of the invention is to provide an apparatus and method of the above character in which a negative pressure is created within the vessel to reverse the flow of blood in the vessel.
Another object of the invention is to provide an apparatus and method of the above character in which it is only necessary to stop the flow of blood in a vessel of a patient for a very short period of time.
Another object of the invention is to provide an apparatus and method in which a working space is provided in the vessel free of blood for treatment of the stenosis.
Another object of the invention is to provide an apparatus and method of the above character in which material which is dislodged during the treatment of the occlusion or stenosis is removed by suction.
Another object of the invention is to provide an apparatus and method of the above character in which blood is shunted around the working space.
Another object of the invention is to provide an apparatus and method in which a cutting device is utilized for treatment of the stenosis or atheroma in the vessel and in which the material removed from the stenosis or atheroma is aspirated out of the operating space.
Another object of the invention is to provide an apparatus and method of the above character in which the amount of material removed from the stenosis or atheroma can be precisely controlled.
Another object of the invention is to provide an apparatus and method of the above character which makes it possible to treat stenoses or occlusions in the vessel which are normally not accessible for surgical procedures.
Another object of the invention is to provide an apparatus and method of the above character which utilizes two spaced apart balloons to create the working space in the vessel.
Another object of the invention is to provide an apparatus and method of the above character that can be utilized to create a working space in a vessel having a bifurcation therein and in which the working space includes the bifurcation.
Another object of the invention is to provide an apparatus and method of the above character which utilizes three spaced apart balloons to create the working space in the vessel having a bifurcation therein.
Another object of the invention is to provide an apparatus and method of the above character which includes a control console for controlling the inflation of the blood flow pump.
Another object of the invention is to provide an apparatus and method of the above character which is particularly adapted for use with the carotid vessels.
FIGS. 10A-E illustrate the use of an embodiment of the catheter of the present invention in an emboli containment treatment procedure.
Referring to
Catheter 10 generally comprises an elongate flexible tubular body 16 extending between a proximal control end 12 and a distal functional end 14. Tubular body 16 has a main lumen 30 which extends between ends 12 and 14. Main lumen 30 terminates in a proximal opening 23 and a distal opening 27. A smaller inflation lumen 32, configured in a side-by-side relationship with main lumen 30, extends along the length of tubular body 16 and may terminate within or near an occlusion balloon 26 mounted on the distal end 14 of catheter 10, as described below. Inflation lumen 32 is in fluid communication with balloon 26, such that fluid passing through inflation lumen 32 may be used to inflate or deflate balloon 26. In some embodiments, the inflation lumen may originate at a point distal to the proximal end 12, and extend distally from that point in a side-by-side configuration with main lumen 30.
In some embodiments, instead of an occlusion balloon 26, distal end 14 is provided with a mechanical occlusive device such as a pull-wire activated braid which filters all particles larger than 12 microns. Alternatively, other occlusive filtering devices may also be used, as is known by those of skill in the art.
A control manifold 19 is provided at the proximal end 12 of catheter 10. Control manifold 19 is generally provided with a number of ports to provide access to the catheter lumen. For example, for the embodiment depicted in
Manifold 19 is preferably formed out of hard polymers or metals, which possess the requisite structural integrity to provide a functional access port to the catheter lumen, such as for balloon inflation or fluid aspiration. In one preferred embodiment, manifold 19 is integrally formed out of medical grade polycarbonate. Other suitable materials may be used to form manifold 19, such as polyvinyl chloride, acrylics, acrylonitrile butadiene styrene (ABS), nylon, and the like.
Manifold 19 is attached to tubular body 16 so that the various ports are placed in communication with the appropriate lumen, as described above in connection with
The length of tubular body 16 may be varied considerably depending upon the desired application. For example, where catheter 10 is to be used as part of an emboli containment system for treatment of carotid artery disease, with catheter 10 being introduced at the groin, the length of tubular body 16 may range from 80 to 110 centimeters, and is preferably 95 cm. Other treatment procedures, requiring a longer or shorter tubular body 16, are easily accommodated by the present invention, by forming a tubular body 16 of the desired length during the manufacturing process.
The outer diameter of tubular body 16 may also be varied considerably, and in most cases, will depend upon the intended treatment procedure for which catheter 10 will be used. That is, the outer diameter of tubular body 16 must be large enough to be capable of forming a main lumen 30 which can slidably accommodate the other catheters used in the emboli containment system, as described in detail below. However, the outer diameter of tubular body 16 must also be smaller than the internal diameter of smallest blood vessel through which catheter 10 passes during the selected treatment procedure. In general, the diameter of main lumen 30 may range from at least about 0.05 inches to about 0.12 inches, and be capable of accommodating many types of catheters to be used therein, while still maintaining a low profile for the diameter of tubular body 16.
For many treatment applications, it has been found that a tubular body having an outside diameter of no more than about 0.135 inches (10 French) is preferred. Advantageously, with an outer diameter of this size, main lumen 30 may have an internal diameter of about 0.10 inches, making lumen 30 capable of accommodating a wide variety of treatment catheters, or catheters used for diagnostic purposes. Of course, as will be appreciated by those of skill in the art, where the catheters intended to be inserted into lumen 30 are known to have outer diameters significantly smaller than 0.10 inches, such that lumen 30 may be smaller than 0.10 inches and still accommodate them, a tubular body 16 having an outer diameter of less than 0.135 inches may be selected.
Although not required, the interior surface of lumen 30 may be provided with a liner 35 formed of a lubricous material, to reduce the frictional forces between the lumen surface and the catheters which are inserted into lumen 30. In one preferred embodiment, liner 35 is formed out of polytetrafluoroethylene (referred to herein as “PTFE”). Lubricous materials other than PTFE, which are biocompatible, fairly flexible, and easily mounted to other polymeric materials of the type used to form catheter tubular bodies, may also be used to form liner 35. Examples of such materials include polyethylene, PEBAX®, nylon, and the like. Where increased flexibility of the distal end 14 of catheter 10 is desired, PEBAX® may be used in place of PTFE along a selected portion of distal end 14, such as the distal most 15-20 cm of end 14.
To minimize the outer diameter of tubular body 16, it is preferable that inflation lumen 32 be as small as possible in accordance with its function. That is, inflation lumen 32 is preferably no larger than required to provide sufficient fluid to balloon 26 for rapid inflation, or so that fluid may be quickly withdrawn from balloon 26 during deflation. For compliant expansion balloons of the type described below, inflation lumen diameters of from about 0.008 inches to about 0.018 inches are satisfactory, with a diameter of about 0.014 inches being preferred for some applications.
Furthermore, in one embodiment, as illustrated in
It will be appreciated by those of skill in the art that other cross-sectional configurations of lumen 32a may be provided and still function to reduce the profile of tubular body 16. For example, triangular, rectangular, or other non-oval cross sectional configurations are easily adapted to lumen 32a, and the manner of incorporating such alternative cross-sectional configurations will be readily apparent to those of skill in the art in view of the description which follows.
A variety of different manufacturing methods may be used to alter the cross-sectional configuration of lumen 32, as will be appreciated by those of skill in the art. In one preferred method, lumen 32 is formed of a polymeric tube, such as a polyimide tube, which has been compressed at one end so that it has the desired oval shape. The polyimide tube is then inserted into a second tube formed of a material having a lower melting point than polyimide, such as 72D PEBAX®. The combination is then heat bonded to another tube defining main lumen 30, such as a braided PEBAX® tube, as described below. The heat bonding takes place at a temperature greater than the melting temperature of PEBAX®, but less than the melting temperature of polyimide, so that the PEBAX® tubes melt fuse to form the two lumen tubular body.
Alternately, the cross-sectional configuration, as well as the cross-sectional area of lumen 32, may also be altered by joining two separate polymeric tubes together to form a continuous inflation lumen 32. One of the tubes, corresponding to the proximal end of catheter 10 as shown in
As illustrated in
Inflatable balloon 26 may be placed in fluid communication with lumen 32a via a fill hole (not shown) extending through tubular body 16 within balloon 26, such that fluid may be introduced into lumen 32 through inflation port 18 to inflate balloon 26. Alternately, lumen 32a may terminate within balloon 26, to provide the requisite fluid communication. Balloon 26 may be attached to tubular body 16 by any suitable manner known to those of skill in the art, such as adhesives or heat bonding.
Tubular body 16 must have sufficient structural integrity, or “stiffness,” to permit catheter 10 to be advanced through vasculature to distal arterial locations without buckling or undesirable bending of tubular body 16. However, it is also desirable for tubular body 16 to be fairly flexible near distal end 14, so that tubular body 16 may be navigated through tortuous blood vessel networks. Thus, in one preferred embodiment, tubular body 16 is made to have variable stiffness along its length, with the proximal portion of tubular body 16 being less flexible than the distal portion of tubular body 16. Advantageously, a tubular body 16 of this construction enables a clinician to more easily insert tubular body 16 into blood vessel networks difficult to reach by a tubular bodies having uniform stiffness. This is because the stiffer proximal portion provides the requisite structural integrity needed to advance tubular body 16 without buckling, while the more flexible distal region is more easily advanced into and through tortuous blood vessel passageways.
In one preferred embodiment, variable stiffness along the length of tubular body 16 is achieved by forming a polymeric tubular body 16 which incorporates along its length a variable stiffness metallic member. The metallic member may comprise a braid or coil, and may have varying braid density or coil pitch at different points along the catheter tubular body. For example, as shown in
As will be appreciated by those of skill in the art, metallic members other than braids may be incorporated into tubular body 16 to create variable stiffness. For example, a metallic coil may be introduced into tubular body 16. The coil may have different pitch along the length of tubular body 16, such that region A is provided with a coil having a lower pitch than that present in region B. The manner of adapting a coil, and other metallic members, to the catheter tubular body in place of a braid will become readily apparent to those of skill in the art in view of the description which follows.
The precise density of the braiding provided to regions A and B can be varied considerably at the point of manufacture, such that catheters having a variety of different flexibility profiles may be created. Moreover, the braid density may be varied within catheter regions A and B as well, by providing a metallic braid which has a braid density gradient along its length. For example, the most proximal part of region A may be provided with a metallic braid 36 having a braid density of about 60 picks per inch, with the braid density increasing distally at a certain rate so that the final pick count is not more than 110 picks per inch at the distal end.
A variety of different metals, known to be ductile and shapeable into fine wires and flat ribbons, having a diameter of about 0.0005 inches to about 0.005 inches for wires, or the same thickness for a ribbon, may be used to form the metallic braids 36 and 36a or metallic coils. For example, stainless steel, platinum, gold and nitinol, or combinations thereof are all suitable metals. In one preferred embodiment, braid 36 is formed of stainless steel, and has a braid density which varies from 70 picks per inch at the most proximal part of region A, to 100 picks per inch at the most distal part of region B.
Metallic braids 36 may be introduced into the structure of tubular body 16 through conventional catheter forming techniques. For example, tubular body 16 may be formed by braiding over a 72D PEBAX® tube that has a removable core mandrel in the internal diameter supporting the PEBAX® tube, and then inserting the braided tube into a 72D PEBAX® outer tube at the proximal region A and a 35D PEBAX® tube at the distal region B, so that the braid is sandwiched between the inner and outer tubes. A stainless steel support mandrel may be inserted into the removable core mandrel as additional support. A shaping container such as a fluorinated ethylene propylene (FEP) shrink tube is inserted over the outer PEBAX® tube, and the entire apparatus may then be placed in a hot box or oven kept at a temperature slightly greater than the melting temperature of the PEBAX® tubes. The PEBAX® tubes will melt and fuse together, and once cooled, will form a tubular body incorporating the metallic braid. The shaping container and mandrels may then be removed and discarded.
In another embodiment, variable stiffness of tubular body 16 may be achieved by forming regions A and B of tubular body 16 out of polymeric materials having differing degrees of stiffness. For example, one half of an inner tube of 72D PEBAX® may be inserted into an outer tube of 35D PEBAX®, and the other half of the inner tube may be inserted into a 72D PEBAX® outer tube. The combination may then be heat fused, as described above. The 35D/72D PEBAX® combination forms a more flexible tubular body than the region 72D/72D PEBAX® combination. More or less flexible materials may be used as desired to alter the flexibility of the resulting tubular body. Furthermore, the flexibility of the various regions of a tubular body formed in this manner may be varied further by incorporating a metallic member having either a uniform density, or a varying density, into the tubular body, as described above.
In another preferred embodiment, variable stiffness along the length of the tubular body may be achieved by using different metallic members in regions A and B. For example, proximal region A may be provided with a multilayer coil, while distal region B may be provided with a braid. Alternately, proximal region A may be provided with a metallic braid, while distal region B may be provided with a single layer coil. As discussed above, the densities of the metallic members in the respective sections may be varied considerably to select for a desired variable stiffness profile, as will be appreciated by those of skill in the art.
In one preferred embodiment, variable stiffness along the length of the tubular body is achieved by keeping the braid density constant along the length of tubular body 16 and then forming the proximal and distal portions of tubular body 16 of polymeric materials of differing stiffness. For example, braid density may be uniform and range from 60-80 picks/inch, more preferably be about 70 picks/inch, with region A being formed of 72D PEBAX® and region B being formed of 25-50D PEBAX®. Alternately, region A can be formed of high density polyethylene and region B of low density polyethylene.
Moreover, any of a variety of different polymeric materials known by those of skill in the art to be suitable for catheter body manufacture may be used to form tubular body 16. For example, tubular body 16 may be formed out of PEBAX®, blends of PEBAX®, and nylons, polyetheretherketone (PEEK), polyethylenes, and HYTREL®, and the like. Different materials might also be combined or blended to select for desirable flexibility properties.
Also, although tubular body 16 has been described in the context of having two regions of differing flexibility, it will be readily appreciated by those of skill in the art that three or more regions of differing flexibility may easily be provided, by adapting the teachings contained herein.
In the above-discussed embodiments, and all other embodiments of the present invention, it may be preferred to provide main lumen 30 and the outer surface of tubular body 16 with a hydrophillic coating, a hydrophobic coating, or combinations thereof. For example, main lumen 30 may be provided with a hydrophobic coating, such as silicone, while tubular body 16 is provided with a hydrophillic coating, such as polyvinyl pyrrolidone (PVP), polyurethane blends, copolymers of acrylonitrile, and the like. Other hydrophobic and hydrophillic coatings, as known to those of skill in the art, may also be used. In addition, any of a variety of antithrombogenic coatings, such as heparin, may also be applied to the catheter of the present invention, alone or in combination with other coating types.
Referring to
The distal end 14 of catheter 10 is also preferably provided with a radiopaque material 44. Advantageously, radiopaque material 44 serves as a marker to help the clinician position catheter 10 during a medical procedure. Various well-known radiopaque materials may be used in distal end 14, such as platinum, gold, and platinum-iridium blends. The full length, or part of the length of the tubular body, may also be radiopaque by blending radiopaque materials in the polymeric materials used to form the body. Furthermore, radiopacity of the tip can also be achieved by loading (i.e., comparing) the distal tip 50 with a sufficient amount of barium sulfate. Alternatively, bismuth subcarbonate, bismuth trioxide or bismuth oxychloride may be used as a radiopaque filler. Also, radiopacity may be achieved by using radiopaque wire or flat ribbon to make the braid or coil.
Illustrated in
Catheter 100 comprises an elongate flexible tubular body 116 having proximal end and distal end 114. An inflatable balloon 126 of the same type as inflatable balloon 26 is coaxially mounted on tubular body 116 on the end 114 of catheter 100. The tubular body 116 has centrally disposed inflation lumen 132 in fluid communication with balloon 126, such that fluid passing through lumen 132 may be used to inflate balloon 126. Alternatively, fluid may be withdrawn from lumen 132 to deflate balloon 126. As shown in
The emboli containment system also comprises catheter 200 comprising an elongate flexible tubular body 216 having proximal end and distal end 214. Catheter 200 is also provided with a generally centrally disposed lumen 230 extending from the proximal end to the distal end of catheter 200, and through which catheter 100 is coaxially and slidably mounted.
The distal end 214 of catheter 200 is provided with means for performing a medical procedure, such as an apparatus for treating stenotic lesion 55. In the embodiment of the invention shown in
The operation and use of the emboli containment system utilizing the catheter of the present invention for treating occluded vessels may now be briefly described in connection with an occlusion formed by a stenosis in a carotid artery, as illustrated in FIGS. 10A-E.
Catheter 100 is inserted into an incision into a femoral artery of a patient and is advanced through that artery into the aorta of the patient and into the ostium of the carotid artery to be treated. After catheter 100 has been introduced, catheters 10 and 200, with balloons 26 and 226 completely deflated, are introduced over catheter 100 and are advanced into the ostium of the carotid artery and into the lumen or passageway of the vessel as shown in FIGS. 10A-E.
The emboli containment system is advanced until catheter 10 is proximal of a stenosis 55 in the vessel lumen 50 to be treated. Balloon 26 is then inflated by introducing a suitable inflation medium such as a radiopaque liquid into port 18 to cause it to pass through the balloon inflation lumen 32 to inflate balloon 26, as shown in
Catheter 100 is then advanced through stenosis 55 as shown in
For emboli containment systems featuring balloon dilatation treatment, it is desired to compress the plaque or material forming the stenosis to provide a larger vessel. Thus, catheter 200 is advanced over catheter 100 to cause distal end 214 with balloon 226 thereon to be advanced into the working space. As soon as balloon 226 has been properly positioned within stenosis 55, balloon 226 is inflated with a suitable inflation medium, as for example a radiopaque liquid. Balloon 226 can be inflated to the desired pressure to cause compression of the plaque of the stenosis 55 against the sidewall 58 of lumen 50 by the application of appropriate inflation pressure. As in conventional angioplasty procedures, balloon 226 can be formed of a non-elastic relatively non-compliant material so that appropriate pressures, such as 10-15 atmospheres, can be used within balloon 226 to apply compressive forces to the vessel without danger of rupturing the vessel. It should be appreciated that the non-elastic capabilities can also be achieved by a composite elastic material.
Once the clinician is satisfied that the occlusion forming stenosis 55 has been sufficiently compressed, balloon 226 can be deflated. After the appropriate dilation of stenosis 55 has been accomplished, catheter 200 can be removed from the stenosis. Moreover, in one preferred method, catheter 200 is completely withdrawn from the emboli containment system, and an irrigation catheter is inserted over catheter 100 and through lumen 30, as described in our copending application entitled METHOD FOR EMBOLI CONTAINMENT, Ser. No. 08/812,875, filed Mar. 6, 1997, now U.S. Pat. No. 5,833,644, the entirety of which is incorporated by reference. Fluid introduced into the working space may be removed by supplying a negative pressure or suction to aspiration port 20. This creates a negative pressure within space 30a defined by the interior surface of lumen 30 and outer tubular body 216, to suck or aspirate blood or other fluids in lumen 50 into space 30a and out of aspiration port 20. In this manner, irrigation and aspiration of the working space may take place so that any plaque coming off the occlusion forming the stenosis 55 can be aspirated out of the vessel. Subsequently, balloon 26 and balloon 126 can be deflated to permit normal blood flow through the vessel lumen 50. The entire catheter assembly can then be removed and a suture applied to the incision created to obtain access to the femoral artery.
In general, the catheter apparatus is for treatment of a stenosis in a lumen in a blood carrying vessel. It is comprised of a main catheter and a balloon-on-a-wire device. The main catheter is comprised of a first flexible elongate tubular member having proximal and distal extremities. A first inflatable elastic balloon having an interior is coaxially mounted on the distal extremity of the first flexible elongate tubular member. The first flexible elongate tubular member has a balloon inflation lumen therein in communication with the interior of the first balloon. The first elongate tubular member has a main lumen therein extending from the proximal extremity to the distal extremity and exiting through the distal extremity. An adapter is mounted on the proximal extremity of the first flexible elongate tubular member and has a balloon inflation port in communication with the balloon inflation lumen, a therapeutic catheter port and an aspiration port in communication with the main lumen. The balloon-on-a-wire device is comprised of a guide wire having proximal and distal extremities.
A second inflatable elastic balloon has an interior and is coaxially mounted on the distal extremity of the guide wire. The guide wire has a balloon inflation lumen therein in communication with the interior of the second balloon. The balloon-on-a-wire device is slidably mounted in the therapeutic catheter port and in the main lumen of the first elongate tubular member with the proximal extremity of the guide wire being disposed outside of the main lumen. Removable valve means is carried by the proximal extremity of the guide wire and has the capability of forming a fluid-tight seal with respect to the guide wire while permitting relative axial movement of the guide wire and the first flexible elongate tubular member with respect to each other whereby the first balloon can be moved so that it is proximal of the stenosis and the second balloon so that it is distal of the stenosis. The removable valve means includes an inflation port in communication with the balloon inflation lumen and the guide wire. The apparatus is also comprised of means coupled to the balloon inflation port of the first flexible elongate tubular member for inflating the first balloon and means coupled to the balloon inflation port of the removable valve means for inflating the second balloon to create a working space which brackets the stenosis.
More particularly as shown in
The tubular member 316 is provided with a large centrally disposed or main lumen 321 extending from the proximal extremity 317 to the distal extremity 318. It is also provided with a balloon inflation lumen 322 which has a distal extremity in communication with the interior of the first balloon 319 through a port 323. The proximal extremity of the balloon inflation lumen 322 is in communication with a balloon inflation fitting 324 mounted on the proximal extremity 317 of the tubular member 316. The fitting 324 can be of a conventional type as for example a Luer-type fitting which is adapted to be connected to a balloon inflation device (not shown) for inflating and deflating the first balloon 319.
The first tubular member 316 is also provided with an aspiration lumen 326 which exits through the distal extremity 318 and the proximal extremity 317 of the tubular member 316. A Luer-type fitting 327 is mounted on the proximal extremity 317 and is in communication with the aspiration lumen 326. The fitting 327 is adapted to be connected to a suitable aspiration or suction source (not shown) of a conventional type such as a syringe or rubber bulb for aspiration purposes as hereinafter described.
The catheter assembly or apparatus 311 also consists of a second elongate flexible tubular member 331 having proximal and distal extremities 332 and 333. A second inflatable balloon 336 of the same type as the first inflatable balloon is coaxially mounted on the distal extremity 333 in a conventional manner. The tubular member 331 is provided with a large generally centrally disposed arterial blood flow lumen 337 which opens through the distal extremity 333 and is in communication with a Luer-type fitting 338 which as hereinafter described is adapted to be connected to a supply of arterial blood from the patient which for example can be taken from another femoral artery of the patient by the use of a blood pump.
The second tubular member 331 is also provided with a balloon inflation lumen 339 which is in communication with the interior of the second inflatable balloon 336 through a port 341. The proximal extremity of the lumen 339 is in communication with the Luer-type fitting 342 mounted on the proximal extremity 332 of the second tubular member 31 and as with the balloon inflation fitting 324 is adapted to be connected to a balloon inflation-deflation device (not shown) of a conventional type. The second tubular member 331 is also provided with a lumen 343 which also can be used as a guide wire and/or for introducing a saline solution extending from the proximal extremity to the distal extremity. The lumen 343 is sized so that it is adapted to receive a conventional guide wire 346 as for example a 0.014″ or 0.018″ guide wire and extends from the proximal extremity to the distal extremity so that the guide wire 346 can extend beyond the distal extremity of the second tubular member 331. A fitting 347 is provided on the proximal extremity 332 in communication with the lumen 343 for introducing the saline solution.
As shown in
The catheter assembly or apparatus 311 also consists of a third elongate flexible tubular member 351 having proximal and distal extremities 352 and 353. It is provided with a centrally disposed lumen 356 extending from the proximal extremity 352 to the distal extremity 353 and through which the second tubular member 331 is coaxially and slidably mounted.
Means 357 is provided on the distal extremity 353 of the third tubular member 351 for performing a medical procedure. In the embodiment of the invention shown in
The operation and use of the catheter assembly or apparatus 311 in the method of the present invention for treating occluded vessels may now be briefly described in connection with an occlusion formed by a stenosis in a vessel not having a bifurcation therein as for example in saphenous graft or in one of the right and left carotid arteries, also called internal and external carotid arteries, of a patient in connection with the illustrations shown in
After the guiding catheter has been appropriately positioned, the guide wire 346 is introduced separately into the guiding catheter or along with the catheter assembly 311. The distal extremity of the catheter apparatus or assembly 311 with all of the first, second and third balloons 319, 336 and 358 completely deflated, is introduced into the guiding catheter 363 along with or over the guide wire 346 and is advanced through the guiding catheter 363 into the ostium 366 of the carotid artery or vessel 367 and into the lumen or passageway 368 of the vessel as shown in
The distal extremity of the catheter assembly 311 is advanced until it is just proximal of a stenosis 369 in the carotid artery 367 to be treated. The balloon 319 is then inflated by introducing a suitable inflation medium such as a radiopaque liquid into the fitting 324 to cause it to pass through the balloon inflation lumen 322 through the port 323 and into the interior of the first balloon 319 to inflate the same as shown in
While a reverse flow of blood is occurring in the vessel 367, the guide wire 346 is advanced through the stenosis 369 as shown in
With the guide wire 346 remaining in position, the second elongate flexible tubular member 331 with the second balloon 336 thereon in a deflated condition is advanced over the guide wire 346 through the stenosis 369 until the second balloon 336 is distal of the stenosis 369 as shown in
Prior to, during or after inflation of the second balloon 336, the guide wire 346 can be removed. However, it is preferable to remove the guide wire 346 as soon as the second balloon 336 has been advanced so that it is beyond the stenosis 369. At this time, and certainly prior to complete inflation of the second balloon 336, blood is shunted across the stenosis 369 and into the lumen 368 distal of the second balloon 336 by introducing blood through the fitting 338 and into the centrally disposed blood flow lumen 337 in the second tubular member 331 so that it exits out the central lumen 337 distal of the second balloon 336. The blood which is supplied to the fitting 337 can be taken from another femoral artery of the patient and pumped into the fitting 338. In addition, if desired, the blood which is aspirated in the space distal of the first balloon 319 can be appropriately filtered and also supplied to the fitting 338. By shunting blood past the stenosis 369 in this manner it can be seen that blood is being continuously supplied to the carotid artery of the patient during the time that the second balloon 336 is inflated and occludes the lumen 368 in the vessel 367.
As soon as the second balloon 336 has been inflated, it can be seen that there is provided a working space 376 (
Assuming that it is desired to compress the plaque or material forming the stenosis 369 to provide a larger lumen, opening or passageway through the stenosis 369 the third tubular member 51 can be advanced by grasping the proximal extremity 352 to cause the distal extremity with the third balloon 358 thereon to be advanced into the working space 376. As soon as the balloon 358 has been properly positioned within the stenosis 369, the balloon 358 also can be inflated with a suitable inflation medium as for example a radiopaque liquid. The balloon 358 can be inflated to the desired pressure to cause compression of the plaque of the occlusion against the sidewall of the vessel 367 by the application of appropriate pressure. As in conventional angioplasty procedures, the third balloon 358 can be formed of a non-elastic relatively non-compliant material so that high pressures as for example 10-15 atmospheres can be used within the balloon to apply compressive forces to the vessel without danger of rupturing the vessel. It should be appreciated that the non-elastic capabilities can also be achieved by a composite elastic material.
Since the blood flow has been restored to the vessel 367 by the shunt hereinbefore described, the compression of the occlusion forming the stenosis 369 can be carried out for an extended period of time, as for example after a few minutes, if desired to help ensure that a large lumen or passageway is formed through the stenosis 369 as shown in
After the appropriate dilation the stenosis 369 has been accomplished the third balloon can be removed from the stenosis while aspiration of the working space 376 is still ongoing so that any plaque coming off the occlusion forming the stenosis 369 can be aspirated out of the vessel. After the third balloon 358 has been removed from the stenosis, the second balloon 336 and the first balloon 319 can be deflated to permit normal blood flow through the vessel 367 after which the arterial blood flow supply to the fitting 338 can be terminated. The entire catheter assembly 311 can then be removed from the guiding catheter 363 after which the guiding catheter 363 can be removed and a suture applied to the incision created to obtain access to the femoral artery.
In place of the third balloon 358 for causing compression of the occlusion forming the stenosis 367 to create a larger passageway therethrough, an atherectomy device 381 (see
Means is provided for rotating the second tubular member 386 and consists of suitable means such as a spur gear 401 mounted on the proximal extremity 387 of the tubular member 386. The spur gear 401 is driven in a suitable manner as for example by another smaller spur gear 402 which is of greater width than spur gear 401 so as to provide a splined gear connection between the gears 401 and 402. This accommodates the desired longitudinal movement for the tubular member 386 so that the distal extremity 388 of the tubular member 386 can be advanced and retracted in the working space 376 as hereinbefore described. An electrical drive motor 403 is provided for driving the gear 402.
Atherectomy means 406 is provided on the distal extremity 388 of the flexible elongate tubular member 386. As shown in
When the distal extremity 388 of the flexible elongate tubular member 386 has been introduced into the working space 376, the end or tip 409 of the flexible elongate member 407 of the atherectomy means 406 is free. A saline solution is introduced into the fitting 357. Thereafter the motor 403 can be energized to cause rotation of the tubular member 386 and to thereby cause rotation of the helically wound flexible elongate member 407 to cause its free end or tip 409 to be moved outwardly radially under centrifugal force to bring the cutting edge 412 into engagement with the plaque 369 in the stenosis 369 to cause progressive removal of the plaque forming the stenosis 369 to enlarge the passageway extending through the stenosis. Because of the rounded configuration of the tip 409, the tip 409 will not dig into the vessel wall but will only remove plaque which is engaged by the cutting edge 412. As the plaque is being removed, the saline solution introduced through the fitting 396 into the space 376 picks up the plaque particles or emboli as they are being removed. The saline solution with the plaque or emboli therein is removed through the spiral groove 398 and through the aspiration port 327. The flexible elongate tubular member 386 can be moved back and forth so that the cutting tip 409 engages the length of the stenosis 369 so that substantially all of the stenosis 369 can be removed.
Means is provided to sense when sufficient plaque has been removed from the stenosis 369 and to ensure that cutting edge 412 does not cut into the vessel wall. An ultrasonic sensor 416 (see
As soon as a desired amount of plaque has been removed from the stenosis 369 to provide the desired passage through the stenosis, rotation of the tubular member 386 is terminated after which the tubular member 386 can be withdrawn followed by deflation of the second balloon 336 and withdrawing it. Deflation of the first balloon 316 then occurs after which it is withdrawn from the vessel 367. Thereafter, the guiding catheter 363 can be removed and the incision closed as hereinbefore described.
In order to ensure that restenosis will not take place, it may be desirable to place a cylindrical stent 426 in the stenosis 369. Such a stent 426 can be a self-expanding stent formed of a suitable material such as a superelastic Nitinol and movable between unexpanded and expanded conditions. Such a stent 426 can be placed by a suitable catheter apparatus 431 of the type shown in
After the stent 426 has been discharged out of the end of the first flexible elongate tubular member 316, the stent 426 will self expand toward its expanded condition until it is in engagement with the wall of the vessel in the vicinity of the occlusion forming the stenosis 369 to frictionally retain the stent in engagement with the vessel wall. As soon as the stent 426 is in engagement with the vessel wall, the second balloon 336 can be deflated as can the first balloon 319. The first deflated balloon 336 can then be withdrawn through the interior of the cylindrical stent 426. This can be followed by deflation of the first balloon 319 and the removal of the flexible elongate tubular member 316 with its first balloon 319 and the flexible tubular member 331 with its second balloon 336, along with the flexible elongate member 436 until the entire catheter assembly or apparatus 431 has been removed from the guiding catheter 363. Thereafter the guiding catheter 363 can be removed and the incision sutured as hereinbefore described.
In
As hereinafter explained, the apparatus 451 shown in
The tubular member 477 is also provided with a large lumen 491 having a suitable size as for example 0.045″ which is adapted to slidably receive therein a therapeutic balloon catheter 492 and a perfusion balloon catheter 493. It is also provided with another lumen 496 having a suitable size as for example 0.026″ which is adapted to receive a balloon-on-a-wire catheter 497. It is also provided with an aspiration lumen 501 having a suitable size as for example 0.025″ and an irrigation lumen 502 having a suitable size as for example 0.015″. There is also provided another lumen 503 which can be used for other purposes.
The therapeutic balloon catheter 492 and the perfusion balloon catheter 493 are constructed in a manner similar to the balloon catheters hereinbefore described. Thus the perfusion balloon catheter 493 is provided with a flexible elongate tubular member 506 having proximal and distal extremities 507 and 508. A balloon 509 formed of an elastic material is secured to the distal extremity 508 by suitable means such as an adhesive (not shown) and is adapted to be inflated through a port 510 in communication with a balloon inflation lumen 511. The tubular member 506 is also provided with a blood perfusion lumen 512 which is centrally disposed therein. The proximal extremity 507 of the tubular member 506 is connected to a Y adapter or fitting 513 of which the central arm 514 is in communication with the blood perfusion lumen 512 and is provided with a Luer-type fitting 516. The side arm 517 of the fitting 513 is in communication with the balloon inflation lumen 511 and is provided with a Luer-type fitting 518 adapted to be connected to a source of pressure as hereinafter described.
The therapeutic balloon catheter 492 consists of a tubular member 521 having a proximal and distal extremities 522 and 523. A balloon 524 formed of a non-elastic material is secured to the distal extremity 523 by suitable means such as an adhesive. A port (not shown) is in communication with the interior of the balloon 524 and is in communication with a balloon inflation lumen 526. A Luer-type fitting 527 is mounted on the proximal extremity 522 and is in communication with the balloon inflation lumen 526. Another fitting 528 is mounted on the proximal extremity 522 and is in communication with a large centrally disposed lumen 529 which can receive the perfusion balloon catheter 493 for slidable movement as hereinafter described.
The balloon-on-a-wire catheter 497 is slidably mounted in the lumen 496 and consists of a guide wire 531 of a conventional construction having a suitable diameter as for example 0.018″ and having a proximal and distal extremities 532 and 533. A balloon 534 formed of a non-elastic material is mounted on the distal extremity 533 and is secured thereto by suitable means such as an adhesive (not shown). The proximal extremity of the balloon 534 is secured to the distal extremity of a tubular member 536 formed of a suitable material such as plastic and which is coaxially disposed on the guide wire 531. The tubular member 536 extends the length of the guide wire to the proximal extremity and is connected to a Luer-type wye fitting 537 and is in communication with an annular lumen 538 disposed between the tubular member 536 and the exterior surface of the guide wire 531. The lumen 538 is in communication with the interior of the balloon 534 for inflating and deflating the balloon 534. The balloon-on-a-wire catheter 497 is adapted to be introduced through a fitting 541 carried by a tube 542 mounted in the manifold 486 and in communication with the lumen 496 in the multi-lumen elongate tubular member 477.
A tube 546 is mounted in the manifold 486 and is in communication with the large lumen 491 and is provided with a fitting 547 which is adapted to receive the perfusion balloon catheter 493 and the therapeutic balloon catheter 492 as hereinafter described. Another tube 551 is provided in the manifold 486 and is in communication with the aspiration lumen 501. It is provided with the fitting 552. Another tube fitting 553 is mounted in the manifold 486 and is in communication with the irrigation lumen 502 and is provided with a fitting 554.
The various fittings for the catheter as hereinbefore described are adapted to be connected into a control console 571. The control console 571 consists of a rectangular case 572 which is provided with a front panel 573.
A plurality of balloon inflation deflation devices 576 of a conventional type typically called endoflaters are mounted within the case 572 and have control handles 577 extending through vertically disposed slots 578 provided in the front panel. These endoflaters 576 are labeled as shown in
A three-way valve 616 is associated with each of the endoflaters 576 and has a control knob 617 extending through the front panel 573 and is adaptable to be moved between three positions with a center off position and an aspiration position in a counter-clockwise direction and a pressurized position in a clockwise position as viewed in
Operation and use of the apparatus 451 may now be briefly described as follows. Let it be assumed that it is desired to treat a stenosis occurring in a bifurcation in a carotid artery as depicted by the illustrations shown in
As soon as or during the time this retrograde circulation of blood is established through the roller pump 601, the perfusion balloon catheter 493 extending proximally from the fitting 547 is advanced into the internal carotid 469 past the stenosis 621 at the bifurcation 467. If necessary, a guide wire can be utilized which can be introduced through the perfusion lumen 512 to aide in advancing the perfusion balloon catheter 493 into the internal carotid 469. Any emboli or debris dislodged from the stenosis 621 by crossing the same either by the guide wire or by the distal extremity of the catheter 493 will be picked up by the retrograde flow of blood which is being aspirated through the proximal occlusion balloon catheter 476 to thereby prevent any emboli or debris from entering the brain of the patient. The elastic perfusion balloon 509 is then inflated as shown in
Prior to or after the balloon 509 of perfusion catheter 493 has been inflated, the balloon-on-a-wire catheter 497 extending proximally of the fitting 541 is advanced into the external carotid 469 as shown in
As soon as retrograde flow of blood has been terminated, perfusion of blood is started. This can be accomplished by connecting a cannula (not shown) to the fitting 516 of the perfusion catheter 506 and to obtain a supply of blood from the femoral artery in the other leg of the patient. Alternatively, an outside blood supply can be used. Thus fresh blood will be supplied from the femoral artery of the patient directly into the perfusion balloon so that it is discharged distally of the perfusion balloon 509 as shown by the arrows 628 to continue to supply blood to the carotid artery. It has been found that it is unnecessary to a supply perfusion of blood to the external carotid artery because there is sufficient auxiliary circulation in that carotid artery during the time the procedure is taking place.
In the event there is inadequate pressure on the arterial blood being perfused to overcome the resistance in the lumen 469, the roller pump 601 can be utilized by merely operating the same in a reverse direction and connecting it between the cannula and the perfusion catheter.
After the lesion or stenosis 621 has been bracketed as hereinbefore described and a working space 636 formed adjacent the stenosis or lesion 621, a therapeutic procedure can be employed. By way of example this can consist of advancing the therapeutic balloon catheter 492 over and axially of the perfusion catheter 493 to bring its balloon 524 into registration with the stenosis 621 as shown in
As hereinbefore described with a previous embodiment, in place of the therapeutic balloon catheter, other types of catheters can be utilized as for example one incorporating an atherectomy device of the type hereinbefore described to facilitate removal of the stenosis. It is readily apparent that during these procedures if it is necessary to supply a saline solution or a heparinized solution into the working space that the working space can also be continued to be aspirated to remove any debris or emboli which occur during the procedure.
Let it be assumed that the desired therapeutic actions have been undertaken and that the stenosis 621 has been reduced and substantially eliminated so that there is adequate flow through the internal carotid. If it can be seen that there also is a stenosis in the external carotid, the balloon-on-a-wire catheter 497 and the perfusion catheter 493 can be withdrawn and moved so that they enter the opposite carotid to permit therapeutic treatment of a stenosis occurring in the other carotid.
When all the desired therapeutic procedures have been accomplished, the supply of saline or contrast solution can be terminated and the therapeutic balloon 524 deflated. The balloon 534 of the balloon-on-a-wire catheter can be deflated as well as the perfusion balloon 509. Perfusion of blood through the perfusion catheter can be terminated. The perfusion balloon catheter 493 and the balloon-on-a-wire catheter 497 can be retracted into the main multi-lumen tubular member 477 of the proximal occlusion balloon catheter after which the perfusion balloon catheter can be withdrawn carrying with it the other catheters disposed therein. Thereafter, the guiding catheter can be removed and a suture applied to the incision made to gain access to the femoral artery.
It is readily apparent that similar procedures can be carried out with respect to other vessels in the body, such as saphenous vein grafts in the heart, and particularly with respect to vessels in the brain where it is difficult if not impossible to employ surgical procedures as for example with respect to the basilar arteries in which bifurcations appear.
As also herein before explained, the catheter apparatus of the present invention can be utilized for deploying stents. Where that is desirable the apparatus of the present invention, perfusion can be accomplished during employment of the stent.
From the foregoing it can be seen that an apparatus and method has been provided for treating occluded vessels and particularly for treating carotid arteries. The apparatus and method of the present invention is particularly advantageous for the carotid arteries because it permits access to portions of the carotid arteries which are not accessible by surgery.
The catheter apparatus assembly and method of the present invention are also particularly useful for treating other occluded vessels but particularly the carotid arteries because it makes possible the removal of plaque without endangering the patient. An operating or working space is provided while shunting blood around the working space so that there is continued blood flow in the vessel to support the functions which are normally supported by the vessel. As also pointed out above, the apparatus and method of the present invention are particularly useful in connection with vessels having bifurcations therein and in which the stenosis occurs at or near the bifurcation. From the foregoing it can be seen with the apparatus and method of the present invention, retrograde flow of blood is accomplished during deployment of the device to prevent undesired travel of emboli. Occlusion of the vessels is provided to obtain a working space by bracketing the working space with balloons while at the same time maintaining perfusion of blood making it possible to utilize a substantial period of time for undertaking therapeutic procedures with respect to the bracketed stenosis.
In connection with the present apparatus and method for treating occluded vessels, it has been found that it is possible to utilize the apparatus and method without perfusion and other procedures involving the carotid arteries and saphenous vein grafts for periods of time extending over five minutes and greater which has made it possible to simplify the apparatus and the method utilized in conjunction therewith.
With respect to an apparatus or assembly which does not require the use of perfusion, a main catheter 651 utilized as a part of the apparatus is shown in
If it is desired to provide a flexible elongate member 652 which has a greater flexibility at the distal extremity, a different material can be used in the distal extremity 654. For example, the distalmost 5-15 centimeters can be formed of a material such as PEBAX® having a Shore D hardness of 35-50 with the remainder of the flexible elongate member 652 having a Shore D hardness of 65-75.
A supplemental flexible elongate tubular member 661 is provided which has incorporated therein a balloon inflation lumen 662. The supplemental flexible elongate tubular member 661 can be of a suitable size as for example an I.D. of 0.014″ and an O.D. of 0.018″ and formed of a suitable material such as a polyimide. The supplemental flexible elongate tubular member has a length which is almost as long as the flexible elongate tubular member 652 and overlies the outside wall of the flexible elongate tubular member 652 and extends from the proximal extremity to near the distal extremity as shown in
As can be seen from
A main adapter or fitting 686 formed of a suitable material such as plastic is mounted on the proximal extremity 653 of the flexible elongate tubular member 652. It is provided with a first Luer fitting 687 which provides a balloon inflation port 688 in communication with the balloon inflation lumen 662. It is also provided with another Luer fitting 689 which is provided with an aspiration port 691 in communication with the main central lumen 657. The main adapter 686 is also provided with a Tuohy-Borst fitting 692 which is in communication with the central lumen 657. The Tuohy-Borst fitting 692 is adapted to receive therapeutic devices, as for example a balloon-on-a-wire device as hereinafter described and is adapted to form a liquid-tight seal therewith by an o-ring 693.
A balloon-on-a-wire device 701 incorporating the present invention is shown in
It has a suitable length as for example 150 cm. The guide wire 702 is provided with proximal and distal extremities 703 and 704 and is provided with a central lumen 706 extending from the proximal extremity to the distal extremity. The lumen can be of a suitable size as for example 0.010″ I.D. for an 0.014″ O.D. guide wire.
An occlusion balloon 711 is coaxially mounted on the distal extremity 704 of the guide wire 702. The occlusion balloon 711 is preferably formed of the same material as the occlusion balloon 669 on the main catheter 651. The occlusion balloon 711 has proximal and distal extremities 712 and 713. A tube 716 formed of a suitable material such as a polyimide is disposed within the occlusion balloon 711 and has a bore 717 extending therethrough which is sized so that it is slightly larger than the outside diameter of the guide wire 702 so that its proximal extremity can be slipped over the distal extremity 704 of the guide wire 702 and then bonded thereto by suitable means such as an adhesive 718. A plurality of circumferentially spaced apart radially extending inflation holes 719 are provided in the proximal extremity of the tube 716 and are in alignment with similarly spaced holes 721 provided in the distal extremity 704 of the guide wire 702 so that they are in communication with the central lumen 706 of the guide wire 702. The inflation holes 719 as shown are in communication with the interior of the occlusion balloon 711 so that fluid passing from the passage 706 can be utilized for inflating the occlusion balloon 711.
A solid core wire 723 formed of a suitable material such as stainless steel is provided with a proximal tapered extremity 724. The core wire 723 is sized so it is adapted to fit within the lumen 706 of the guide wire 702 and is secured therein by suitable means such as an adhesive 726 or alternatively a weld. The core wire 723 has a tapered portion 723a which commences at the proximal extremity 724 and which is tapered so that the cross-sectional diameter progressively decreases to the distal extremity of the occlusion balloon 711. The core wire 723 is also provided with additional portions 723b and 723c which can be of substantially constant diameter as for example 0.003″. The portion 723 is folded over with respect to the portion 723b so that the portions 723b and 723c lie in a plane to facilitate shaping of the distal extremity of the guide wire 702 during use of the same. The core wire 723 is provided with a distal extremity 727 in which a bend 728 is formed between the two portions 723b and 723c. The bend 728 is secured within a hemispherical solder bump or protrusion 729 which is carried by the distal extremity of a coil 731 formed of a suitable radiopaque material such as platinum or a platinum alloy. The platinum coil 731 can have a suitable outside diameter as for example 0.014″ corresponding to the diameter of the guide wire 702 and can have a suitable length ranging from 1 to 3 cm. The proximal extremity of the coil 731 is secured to the distal extremity of the polyimide tube 716 by suitable means such as an adhesive 732 which can be the same adhesive or a different adhesive 733 utilized for securing the distal extremity 713 of the balloon to the polyimide tube 716 to form a fluid-tight seal between the distal extremity of the occlusion balloon 711 and the distal extremity of the polyimide 716. From this construction it can be seen that the portions 723b and 723c of the core wire 723 in addition to serving as a shaping ribbon are also utilized as a safety ribbon to ensure that the tip 728 and the spring 731 cannot be separated from the guide wire 702. The proximal extremity 712 of the balloon 711 is also secured to the proximal extremity of the polyimide tube 716 and also to the distal extremity 704 of the guide wire 702 to form a fluid-tight seal with respect to the occlusion balloon 711 so that the occlusion balloon 711 can be inflated and deflated through the inflation holes 719 and 721.
Alternative constructions for the distal extremity of the core wire 723 are shown in
A removable inflation fitting 741 or valve attachment 741 is mounted on the proximal extremity of the guide wire 702 and forms a part of the balloon-on-a-wire device 701. The fitting or attachment 741 is formed of a suitable material such as a polycarbonate and is provided with a central bore 742. The attachment or fitting is slid externally over the proximal extremity 703 of the guide wire 702. Means is provided for forming a fluid-tight seal between the proximal extremity 703 of the guide wire 702 and a body 743 of the fitting 741 and consists of an o-ring 746 (see
Means is provided for plugging the bore 706 when the removable attachment or fitting 741 is removed and consists of a plug mandrel 756 formed of a suitable material such as 0.014″ stainless steel solid rod. It is necessary that this rod have a diameter which is greater than the diameter of the lumen 706 and the guide wire 702. The plug mandrel 756 is provided with a progressive portion 756a that tapers down from as, for example from 0.014″ to a suitable diameter as for example 0.008″ to a cylindrical portion 756b.
Means is provided for forming a fluid-tight seal between the plug mandrel 756 which forms a plug mandrel and the body 743 of the attachment or fitting 741 and consists of an o-ring 761 providing suitable sealing means seated within a well 762 provided in the body 743. A thumb screw 763 threadedly engages the body 743 and is provided with a cylindrical protrusion 764 which engages the o-ring and compresses it to form a fluid-tight seal with respect to the plug mandrel 756 by rotation in a clockwise direction of the thumb screw 763. The plug mandrel 756 can be released by a counterclockwise rotation of the thumb screw 763 permitting decompression of the o-ring 761.
An irrigation catheter 766 incorporating the present invention is shown in
Operation of the apparatus shown in
Thereafter the main catheter 651 can be introduced into the femoral artery by use of a large conventional guiding catheter because the main catheter 651 is of a relatively large size, as for example 8 to 9.5 French. In order to eliminate the need for such a large guiding catheter, a smaller conventional guiding catheter 786 of the type shown in
The guiding catheter 786 is conventional and thus will not be described in detail. It consists of a flexible elongate tubular member 787 (see
Assuming that the guiding catheter 786 has been inserted into the main catheter 651 before insertion of the main catheter 651 into the femoral artery, both catheters can be inserted in unison while advancing the distal extremity of the guide catheter 786 so that it precedes the distal extremity of the main catheter 651 and serves to guide the main catheter 651 into the vessel of interest, as for example the vessel 781 having the stenosis 782 therein. The main catheter 651 is then advanced so that its distal extremity is at the proximal side of the stenosis 782. By way of example, the main catheter 651 can be advanced through the aortic arch of the heart and thence into a saphenous vein graft so that the occlusion balloon 669 on its distal extremity is positioned proximal of the stenosis 782. As soon as this has been accomplished, the guiding catheter 786 can be removed.
As soon as the distal extremity of the main catheter 651 has been deployed so that it is just proximal of the stenosis 782 to be treated, an assembly shown in
Let it be assumed that it is now desired to inflate the occlusion balloon 669 carried by the main catheter 651. This can be accomplished in a suitable manner such as with an inflation-deflation device represented schematically by a syringe 802 secured to the fitting 687 (see
The occlusion balloon 711 can then be readily inflated by use of a syringe 805 secured to the fitting 751 of the removable valve fitting or attachment 741 of the balloon-on-a-wire device 701 proximal of the fitting 686 and accessible outside the body of the patient. The occlusion balloon 711 is inflated (see
Now let it be assumed that the occlusion balloon 711 has been inflated with the appropriate working space 803 and that it is desired to introduce a therapeutic balloon catheter 801 into the working space 803 to treat the stenosis 782. If the therapeutic catheter 801 is not in the main catheter 651 as hereinbefore described, this can be readily accomplished in the present invention by inserting a plug mandrel 756 into the open end of the lumen 706 of the guide wire 702. After the plug mandrel 756 has been inserted, the syringe 805 can be removed after which the thumb screws 748 and 763 can be loosened to permit the o-rings therein to become decompressed and to release the guide wire 702 and the plug mandrel 756 to permit the fitting or valve attachment 741 to be slipped off to provide a proximal end on the guide wire 702 which is free of obstructions. During removal of the valve attachment or fitting 741, the occlusion balloon 711 remains inflated and continues to be disposed distally of the stenosis 782. The occlusion balloon 669 also remains inflated because the syringe 802 remains attached to the fitting 686 and is disposed proximal of the stenosis 782.
The conventional therapeutic catheter 801 then can be delivered over the guide wire 702 if it is not already present. The therapeutic catheter 801 is provided with a flexible elongate tubular member 806 having proximal and distal extremities 807 and 808 with a central flow passage (not shown) extending between the same. A therapeutic balloon 809 on its distal extremity is adapted to be inflated to therapeutic pressures ranging from 4-20 atmospheres through a balloon inflation lumen (not shown) carried by the flexible elongate tubular member 806 through an adapter 811 mounted on the proximal extremity 807. The therapeutic balloon 809 can be considered to be means for performing work carried by the distal extremity 808 of the flexible elongate tubular member 806. The adapter 811 can be removable of the type hereinbefore described or alternatively can be permanently attached thereto. Assuming that it is a removable adapter, the removable adapter 811 is provided with knobs 812 and 813 carrying o-rings (not shown) adapted to establish fluid-tight seals with the flexible elongate member 806 and the plug mandrel 756, respectively. It is also provided with an inflation port 816 similar to those hereinbefore described which is in communication with the inflation lumen (not shown) provided in the flexible elongate tubular member 806 for inflating the therapeutic balloon 809.
After the balloon catheter 801 has been positioned by the use of radiopaque markers (not shown) conventionally employed in such devices, the therapeutic balloon 809 is disposed so that it is in general alignment with the stenosis 782 as shown in
Let it be assumed that during the compression of the plaque forming the stenosis 782, additional emboli 804 are formed as shown in
The bulb 821 is provided with another one-way check valve 823 which is connected to a flexible collection bag 824. The bulb 821 makes it possible to generate a vacuum corresponding approximately to 3-30″ of mercury. Thus, by compressing the bulb 821 by hand, it is possible to create suction within the chamber or space 803 formed in the vessel between the occlusion balloons 669 and 711 each time the bulb 821 is compressed and released. Alternatively, the aspiration can be accomplished by use of a syringe in place of the bulb 821 and the collection bag 824. Saline liquid supplied through the irrigation catheter 766 carrying the emboli 818 is aspirated through the central lumen 657 of the main catheter 651. The aspirated liquid in each cycle of operation created by pressing the bulb 821 is delivered to the collection bag 824. With such a procedure it has been found that it is possible to aspirate emboli as large as 600 μm. Such removal can be assured by observing when clear liquid exits outside the body from the aspiration port 691. A chamber having a length ranging from 3 cm to 15 cm can be totally cleared of emboli within a short period of time ranging from 5 to 30 seconds. Alternatively, irrigation can be accomplished by removing the therapeutic catheter 801 after deflating the therapeutic balloon 809. The irrigation catheter can be advanced over the balloon-on-a-wire device 701 until the distal tip is just proximal of the occlusion balloon 711 as shown in
After all of the emboli 804 have been removed, introduction of saline through the tube 819 is halted. It should be appreciated that the ports for irrigation and aspiration can be reversed in function if desired. Thereafter, the occlusion balloon 711 is deflated by removing the plug 756 and utilizing a syringe 805, after which the occlusion balloon 669 is deflated permitting blood flow to be reestablished in the vessel 781. Alternatively, the occlusion balloon 669 can be first deflated and aspiration commenced at that time, permitting emboli trapped distally of the occlusion balloon 669 by blood flowing from the proximal side of the occlusion balloon 669 to be aspirated through the central lumen 657. In order to prevent excessive expansion of the vessel 781 being treated, the pressure of the irrigation liquid is typically maintained under 30 psi. This pressure preferably should be below the occlusion balloon pressure.
If it is desired to deliver a stent to the site of the stenosis formed by the plaque 782, this can be readily accomplished during the same procedure. Typically it is desirable to permit the blood to flow normally for a period of several minutes after which the occlusion balloon 669 can be reinflated by the syringe 805 and the occlusion balloon 711 can be reinflated by inserting the removable valve attachment 741 if it has been removed of the balloon-on-a-wire device 701 and utilizing the syringe 803 to reinflate the occlusion balloon 711. The plug mandrel 756 can be inserted to keep the occlusion balloon 711 inflated after which the valve attachment 741 can be removed.
A conventional stent delivery catheter 826 carrying a stent 827 on its flexible shaft 828 is introduced over the balloon-on-a-wire device 701 and delivered to the site of the dilated stenosis 782 (see
Heretofore the apparatus of the present invention has been utilized for performing a procedure on a saphenous vein graft where there are no branches to be dealt with. An apparatus incorporating the present invention also can be useful in connection with vessels in a human being having branches therein, as for example the carotids. For this purpose, a main catheter 831 (see
One of the balloon-on-a-wire devices can be substantially identical to the balloon-on-a-wire device 701 described. The other balloon-on-a-wire device 835 as shown in
Operation and use of the apparatus of the present invention in performing a procedure in a carotid artery is shown in the cartoons in
Another balloon-on-a-wire device such as the balloon-on-a-wire device 701 is then introduced through the catheter port 834 and advanced through the central passage or lumen 657 until it exits from the main catheter 831 after which it is guided into the internal carotid 843 past the stenosis 844 so that the occlusion balloon 711 is distal of the stenosis 844. The occlusion balloon 711 is then inflated as shown by the dotted lines in
The removable valve attachment 741 can then be removed in the manner hereinbefore described so that the proximal extremity of the guide wire 702 is free of obstructions as shown in *
In the event it is desired to deliver a stent into the dilated stenosis 844, this can be accomplished by reinflating the occlusion balloon 669 and then reinflating the occlusion balloons 711 in both of the branches after which a balloon stent delivery catheter 826 of the type hereinbefore described can be delivered over the guide wire 702 in the same manner as the therapeutic balloon catheter 766 and delivered into the desired location and then deployed in the dilated stenosis 844. After the stent 827 has been deposited and the balloon of the stent delivery catheter 826 is deflated, the irrigation and aspiration procedures hereinbefore described can be repeated to remove any emboli within the space formed between the occlusion balloons 711 and 669. The stent delivery catheter 826 can be removed. After a suitable period of irrigation and aspiration, as for example 5 to 30 seconds, the occlusion balloon 711 can be deflated after which the occlusion balloon 669 can be deflated and the balloon-on-a-wire devices 701 and 835 removed along with the main catheter 652.
From the foregoing it can be seen that there has been provided a new and improved apparatus and a method for utilization of the same which makes it possible to carry out such stenosis opening procedures without the perfusion of blood. Complete stenosis procedures can be carried out in a period of time which is less than six minutes for each complete procedure. Even though blood flow is occluded during this period of time, this period of time is much less than the period of time, as for example 30 minutes, required for a conventional endoatherectomy. Thus, the procedures of the present invention can be carried out without endangering the patient, as for example the brain or the heart of the patient.
The desire to eliminate the use of a large guiding catheter for use with the main catheter 651 was hereinbefore discussed. Also, it was hereinbefore disclosed that the main catheter 651 can be inserted independently through a conventional sheath (not shown) in the femoral artery and thereafter a smaller conventional guiding catheter 786 is introduced through the main catheter so that its distal extremity 789 is in the vessel. In other procedures it may be desirable to carry this concept still further, i.e., eliminating the need for a large guiding catheter and also the need for a smaller guiding catheter to be advanced through the main catheter. To do this, it may be desirable to provide a distal extremity on the main catheter 651 which is shaped in a predetermined manner. For example, in the main catheter 651a shown in
Since the main catheters 651a and 651b are relatively flexible, they can be inserted into the femoral artery and have their distal extremities guided into the desired locations with the catheter being selected for the appropriate bend to reach the desired location. With the main catheter having such capabilities, it is possible in connection with the present invention to advance the main catheter 651 into the desired location by the use of a balloon-on-a-wire device of the type hereinbefore described, or alternatively over a conventional guide wire. This makes it possible to eliminate the use of a guiding catheter and therefore substantially simplify the procedures of the present invention and reduce the costs of such procedures.
In connection with the irrigation catheter 766 hereinbefore described in
In the irrigation catheter 766b shown in
Another embodiment of the balloon-on-a-wire device is shown in
An elongate slot 911 is ground into the distal extremity of the guide wire 702 to a suitable depth which is in excess of one half of the diameter of the guide wire 702. The slot 911 is in communication with the lumen 706 and opens into the interior of the balloon 906. A tapered core wire 913 is mounted in the distal extremity 704 of the guide wire 702. The core wire 913 is provided with a portion 913a which has a progressive decrease in diameter extending from the proximal extremity to a portion 913b which is generally of a uniform diameter of a suitable size, as for example 0.003″ and is formed into a bend 916 and extends proximally along the slot 916 and proximally thereof where it is secured to the guide wire 702 by suitable means such as an adhesive 918. A coil spring 921 formed of a suitable material such as stainless steel or platinum extends over the slot 911 and proximally and distally of the slot 911 and is secured thereto by suitable means as solder 922. Positioned in this manner, the coil 921 generally circumscribes the inner circumference of the balloon 906 and serves to protect the balloon 906 from any sharp edges as for example sharp edges formed by the slot 911 in the coil wire 702. A tip coil 926 formed of a suitable radiopaque material such as a platinum or a platinum alloy is mounted over the distal extremity of the guide wire 702 and secured thereto by suitable means such as solder 927. The distal extremity of the tip coil 926 which may have a suitable length, as for example 3 mm, is bonded to the core wire 913b by a solder 928 which encloses the bend 916 and provides a rounded forwardly protruding surface 929. The distal extremity 908 of the balloon 906 is secured to the coils 921 and 926 by an adhesive 931. Similarly, the proximal extremity 907 of the balloon 906 is secured to the guide wire 702 and the portion 913b by an adhesive 932.
The balloon-on-a-wire device 901 can be utilized in the same manner as the balloon-on-a-wire device 701 hereinbefore described. It is believed that the balloon-on-a-wire device 901 has several desirable features. For example the balloon 906 is protected from any sharp edges by the coil spring 921. The slot 911, in addition to providing a means for inflating the balloon, also serves to provide a progressive weakening of the distal extremity of the guide wire 702 to impart additional flexibility to the distal extremity of the device.
By utilizing a balloon-on-a-wire constructions herein disclosed, it is possible to reduce the overall size of the apparatus for the procedures. In view of the fact that guide wires having a size of 0.014″ to 0.018″ are utilized in the present invention, many conventional therapeutic balloon devices can be utilized by advancing the same over such size guide wires. By the provision of removable valve attachments for the balloon-on-a-wire devices, it is possible to use such devices for providing the one or more balloons necessary for a procedure while at the same time making it possible to utilize such devices as guide wires after removing the removable valve attachments on the proximal extremities. This makes it possible to utilize conventional stent delivery catheters, ultrasound catheters and the like by advancing them over the already in place guide wires.
It should be appreciated that it may be possible to eliminate the use of the occlusion balloons 711 which are distal of the proximal balloon carried by the main catheter and distal of the stenosis, since blood flow is occluded during the time that the occlusion balloon 669 is inflated.
Another embodiment of a catheter apparatus incorporating the present invention for treating occluded vessels is shown in
In this regard, it should be appreciated that irrigation and/or aspiration can be accomplished in combination with the catheter apparatus 951 by the use of separate catheters as hereinabove described in connection with
Self-expanding sealing means 966 is mounted on the distal extremity 954. This self-expanding sealing means 966 can take any suitable form. For example, as shown it can consist of a braided structure 967 formed of a suitable shape memory material such as a nickel titanium alloy that will attempt to expand to a predetermined shape memory. Other than shape memory materials, other materials such as stainless steel, titanium or other materials can be utilized in the braid 967 as long as they have the capability of expanding when the self-expanding seal means is released. Also it should be appreciated that the self-expanding seal means 966 can be comprised of an absorbent material which when it absorbs saline or blood expands to form a seal. Such seals can be readily accomplished because it is only necessary to form a seal of approximately one atmosphere to prevent small particles from moving downstream.
In order to prevent abrasion of a vessel, it is desirable to cover the braided structure 967 with a covering 968 of a suitable material such as a polymer which extends over the braided structure 967 and which moves with the braided structure 967 as it expands and contracts. The polymer can be of a suitable material such as silicone, C-FLEX®, polyethylene or PET which would form a good sealing engagement with the wall of the artery.
Means is provided for compressing the self-expanding sealing means 966 so that the apparatus can be inserted into the vessel 781 and consists of an elongate sleeve 1071 having proximal and distal extremities 1072 and 1073 and a bore 1074 extending from the proximal extremity 1072 to the distal extremity 1073. A collar 1076 is mounted on the proximal extremity 1072 of the sleeve 1071 and is positioned near the adapter 956. The collar 1076 serves as means for retracting the sleeve as shown in
Another embodiment of a catheter apparatus for treating occluded vessels incorporating the present invention is shown in
In accordance with the hereinbefore described descriptions, it is apparent that the apparatus can be readily deployed and serve the same function as the main catheter. To accomplish this, the assembly 1081 can be introduced into the femoral artery and the distal extremity advanced into the desired location in the arterial vessel. After it has been properly positioned, the physician can retract the sleeve 1096 to permit the self-expanding seal means 1091 to expand and to form a seal with the wall of the arterial vessel to occlude the arterial vessel and interrupt the flow of blood in the vessel to provide a working space distal of the occlusion formed. This prevents small particles which may thereafter be dislodged from moving downstream. Since a central lumen is available, the therapeutic procedures hereinbefore described can be employed with the catheter apparatus shown in
Thus it can be seen that it has been possible to substantially reduce the complexity of the apparatus utilized in such procedures. This reduces the cost of the apparatus used therein as well as reducing the time required for performing such procedures making the procedures less costly.
It will be appreciated that certain variations of the present invention may suggest themselves to those skilled in the art. The foregoing detailed description is to be clearly understood as given by way of illustration, the spirit and scope of this invention being limited solely by the appended claims.
This application is a divisional of application Ser. No. 10/427,000, filed Apr. 30, 2003, which is a continuation of application Ser. No. 10/011,583, filed Nov. 6, 2001, which is a continuation of application Ser. No. 09/790,220, filed on Feb. 21, 2001, which is a continuation of application Ser. No. 08/813,023, filed on Mar. 6, 1997, now U.S. Pat. No. 6,270,477, which is a continuation-in-part of application Ser. No. 08/650,464 filed on May 20, 1996, now abandoned, the entirety of which is incorporated herein by reference.
Number | Date | Country | |
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Parent | 10427000 | Apr 2003 | US |
Child | 11417570 | May 2006 | US |
Number | Date | Country | |
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Parent | 10011583 | Nov 2001 | US |
Child | 10427000 | Apr 2003 | US |
Parent | 09790220 | Feb 2001 | US |
Child | 10011583 | Nov 2001 | US |
Parent | 08813023 | Mar 1997 | US |
Child | 09790220 | Feb 2001 | US |
Number | Date | Country | |
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Parent | 08650464 | May 1996 | US |
Child | 08813023 | Mar 1997 | US |