MXPA99002595A - Overlay dual balloon catheter and method for use thereof - Google Patents

Abstract

An overlay dual balloon catheter. Two balloons composed of differing materials are employed, the balloons being disposed so as to overlap one another but not being bonded to one another, so that adjacent surfaces of the two balloons are permitted to move relative to one another, to provide improved surface and structural characteristics in a balloon unit. Preferably, an outer balloon, disposed on the exterior of the catheter is composed of latex, silicone, or a thermoplastic elastomer while an inner balloon, disposed underneath the first balloon is composed of a material employed in existing angioplasty balloons such as polyester or polyurethane. The overlay dual balloon catheter may be used in angioplasty, embolectomy and thrombectomy.

Description

"DOUBLE GLOBE PROBE OVERPOST AND METHOD FOR THE USE OF THE SAME" BACKGROUND OF THE INVENTION This invention relates to balloon probes and is particularly related to the use of multiple materials and superimposed construction in a probe balloon unit both for the improvement and adaptation of the characteristics of the balloon unit. Balloons in a balloon probe are used in a channel of the patient's body, commonly a blood vessel, primarily for three purposes: occlusion, distention (eg, angioplasty) and vessel cleansing or removal of blood clots and foreign substances (eg, embolectomy, thrombectomy). To serve the first purpose, the balloon must be flexible enough when it is inflated to completely conform to the inner surface of the body channel, and the surface must have a suitable friction characteristic to hold the balloon in place. For the second purpose, the balloon must be rigid enough to inflate symmetrically even when it is being influenced by asymmetric forces. And for the third object, or purpose, the surface must be resistant to breakage, csn good tension properties, and again - it must have an appropriate friction characteristic. Especially since both surface and structural characteristics such as strength, rigidity and breaking strength are important, a balloon comprising a single material usually requires the acceptance of mutual concessions in the characteristics of the material. Even in view of this, it seems that there are very few attempts to employ multiple materials in a balloon in an effort to minimize mutual concessions in order to bring desirable characteristics to the optimum. One reference, Wang et al., US Patent Number 5,195,969 ("Wang"), proposes "CO-EXTRUDED MEDICAL BALLOONS AND PROBE USING THESE BALLOONS" comprising a multi-layered balloon including a base structural layer with a relatively coarse ethylene polymeric material and a second layer coextruded and apparently bound co-extensively with the base layer, with the second layer preferably being a polyolefin such as polyethylene. However, even this multi-material balloon such as that proposed by Wang has disadvantages. For example, it is often desirable for the balloon to present a non-zirconvolution surface within the body channel when the balloon is deflated, to facilitate passing the balloon therethrough. If you co-extrude a - - strong base material, with for example a smooth surface material, the base material is often insufficiently elastic to relax to a smooth surface configuration when the balloon deflates. In addition, the complete deflation and crushing of the balloon that is resisted by expanding a rigid strong base material is not appreciably assisted by employing a smooth co-coextruded surface layer. Accordingly, there is a need for a novel balloon probe and a method for using same that employs multiple materials and provides a superimposed construction to bring to the optimum both the surface and structural characteristics of the balloon unit.

COMPENDIUM OF THE INVENTION The superimposed double balloon probe and method for the use thereof of the present invention solves the aforementioned problems and fills the aforementioned need by employing two balloons composed of different materials, the balloons being positioned so as to overlap one another and having work portions of the same that are not linked to each other, so that the working portions of the two balloons are allowed to move relative to each other to provide - improved surface and structural characteristics in a balloon unit. Preferably, an external balloon, placed on the outside of the probe is composed of latex, silicone or a thermoplastic elastomer while an internal balloon, placed below the first balloon is composed of a material used in existing angioplasty balloons such as polyester, polyurethane, or polyethylene. Therefore, a main object of the present invention is to provide a novel and improved balloon probe and method for the use thereof. Another object of the present invention is to provide a balloon probe employing superimposed balloons. A further object of the present invention is to provide a probe that optimizes both the surface and structural characteristics of the balloon unit. Still another object of the present invention is to provide a probe that provides means for movement between the adjacent surfaces of the two balloons. The above objects and advantages and other advantages of the present invention will be more readily understood by taking into account the following description - Detailed description of the invention, which is taken together with the following drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partially cut lateral elevation of a balloon probe having a balloon unit in accordance with the present invention, in combination with a probe that is shown in an inflated condition. Figure 2 is an illustrative partially cut-away view of the balloon probe of Figure 1 shown in a partially inflated condition. Figure 3A is a cross section of a blood vessel and a balloon probe in accordance with the present invention that is fed into an obstruction. Figure 3B is a cross section of the blood vessel and a balloon probe of Figure 3A that has burst through the obstruction. Figure 3C is a cross section of the blood vessel whose balloon probe of Figure 3A with the balloon unit having inflated. Figure 3D is a cross section of the blood vessel and the balloon probe in Figure 3A, with the probe and obstruction having been removed from the blood vessel.

- Figure 4A is a cross section of a blood vessel and a balloon probe in accordance with the present invention that is fed along a guidewire to an area of stenosis in the blood vessel. Figure 4B is a cross section in the blood vessel and the balloon probe of Figure 4A, with the balloon unit being positioned in the area of stenosis. Figure 4C is a cross section of the blood vessel and the balloon probe of the Figure 4A, with the balloon unit having inflated against the stenotic material in the stenosis area to release the stenosis area Figure 4D is a cross section of blood vessel in the balloon probe of Figure 4A, with the balloon unit and having deflated in preparation for his retirement. Figure 4E is a cross section of the blood vessel and the balloon probe of Figure 4A, with the probe having been removed from the blood vessel. Figure 5A is a cross section of a blood vessel and a balloon probe in accordance with the present invention that is fed along a guidewire to a previously released stenosis area, such as that of Figure 4C, having the balloon probe a stent placed in a balloon unit of the same.

Figure 5B is a cross section of the blood vessel and the balloon probe of Figure 5A, with the balloon unit and the stent having been placed in the area of stenosis. Figure 5C is a cross section of the blood vessel and the balloon probe of Figure 5A, with the balloon unit being inflated to expand the stent at the site. Figure 5D is a cross section of the blood vessel and the balloon probe of Figure 5A, with the balloon unit having deflated and the stent being placed in place. Figure 5E is a cross section of the blood vessel and the balloon probe of Figure 5A with the probe having been removed from the blood vessel.

DETAILED DESCRIPTION OF THE PREFERRED MODALITY Referring to Figures 1 and 2, a preferred embodiment of the balloon unit 10 for use in a balloon probe 12 comprises an internal balloon 14 fixed at the ends 16 and 18 thereof circumferentially around a probe arrow 20, and an external balloon 22 dimensioned in an almost similar manner superimposed essentially on the upper part of the inner balloon 14. Preferably, the arrow of the probe is a flexible tube formed of a suitable thermoplastic material such as polyethylene, polyvinyl chloride, polyurethane, nylon or the like, although the tube may be formed of stainless steel or other rigid inert material. The inner balloon 14 makes an essentially leak-tight seal at the ends 16 and 18 with the arrow 20 and preferably with the outer balloon 22. The probe 12 is generally adapted for the procedure in which it is to be used, as will be easily appreciated by those who know the technique. For example, a stent placement procedure, which will be described below, requires that probe 12 be structurally adapted to withstand high internal pressure. The outer balloon 22 is also fixed to an arrow 20 of the probe at the ends 24 and 26 thereof, so that the working portions 30 of the inner balloon 14 and the outer balloon 22 are allowed to move relative to each other. the other, in order to provide the improved surface and structural characteristics in the balloon unit 10. Preferably, the ends 24 and 26 of the end balloon 22 are positioned essentially above the ends 16 and 18 of the inner balloon 14; however, the outer balloon 22 may be longer or longer - - short that the inner balloon 14, and can incompletely overlap the inner balloon without deviating from the principles of the present invention, it being important only that the predetermined working portions 30 of the balloons 1-4 and 22 overlap. , a portion of the outer balloon 22 can be "ligated either to the inner balloon 14, where the inner balloon extends beyond it, or to the probe 12, where the outer balloon extends beyond the inner balloon. found that the best results are achieved in the superimposed balloon probe where outer balloon 22 comprises a material, such as latex, silicone or a thermoplastic elastomer, which provides high elasticity and moderate to high surface friction against the body cavity, and wherein the inner balloon 14 comprises a relatively thin membrane of a relatively flexible yet non-elastic material such as polyethylene, polyethylene terephthalate , nylon, polyamide, polyvinyl chloride, polypropylene or other material known in the art to provide flexibility and strength. In addition, the strength or other material properties of any balloon can sometimes be adjusted in manners known in the art. For example, the resistance of polyethylene can be increased by eliminating its polymer chains - thus increasing its density, a process that is often referred to as "guidance". Moderate to high friction is desirable in the material of the outer balloon 22 to retain the probe 12 in place and for better and more complete removal of emboli and highly adherent thromboses. The strong internal balloon 14 supports the outer balloon 22 and reduces the potential for puncture, especially during embolectomy, for resistance to rupture of the balloon unit 10 during the removal of clots from an arteriovenous graft; and to push and pull the balloon unit against the atherosclerotic plaques when used in arteries, or venous valves when used in the venous system. The inner balloon 14 includes an external surface 34 that is immediately adjacent to the inner surface 36 of the outer balloon 22, the two surfaces 34, 36 being allowed to move relative to one another except in the expes 16, 18 and 24, 26 To allow the two surfaces to move somewhat independently of one another a number of advantages are provided in the present invention. For example, the strong semi-rigid inner balloon 14 tends to resist complete deflation and tends, upon deflation, to adopt a loose, zirconvolutional configuration of its outer surface 34, somewhat analogously to a folded or folded parasol. An independently elastic, highly elastic external balloon 22 can provide a superior restoring force to help deflate this inner balloon and place the inner balloon in a configuration that is already tense when the inner balloon is deflated. The external globe always tense and tend to relax to press the inner balloon towards a minimum volume of containment. Further, in the always taut outer globe it may provide an external surface 38 which is smooth even when the outer surface 36 of the inner balloon is loose and convoluted. A smooth outer surface 38 facilitates the insertion of the probe into and subsequent movement of the probe through a body cavity, particularly a small blood vessel. It would additionally be a highly compressed inner balloon, providing smaller working dimensions than the balloon unit 10 providing increased ease in small body cavities, such as small blood vessels. The arrow 20 is provided with at least one luminous flux 32 of inflation, the luminous flux of inflation remaining in communication with the inner balloon 14 through an opening 23, to inflate the inner balloon by the forced introduction of a fluid, such as air or a saline solution, as is understood in the art. Preferably, a space 39 remaining between the - inner surface 36 of the outer balloon 22 and the outer surface 34 of the inner balloon 14 is provided with inflation means, essentially sealing the remaining space between the surfaces 34 and 36 at the ends 16, 18, 24 and 26, in order to allow the outer balloon provides a backup seal for the inflation flow 32. However, this particularity of redundancy is not a requirement for the practice of the present invention. Inflation of the outer globe 22 was then achieved by inflating the inner balloon. The remaining space 39 is normally an unimportant volume since the surfaces 34 and 36 preferably remain in contact with one another. It will be recognized that, while the specific superimposed double balloon probe and the method of using it has been shown as the preferred embodiment of the invention, other configurations could be used in addition to the configurations already mentioned, without deviating from the principles of the invention. invention. In particular, it is proposed that any number of combinations of internal and external balloon materials can be employed to provide an optimum configuration for different uses. In addition, known materials can be processed to optimize their mechanical and chemical properties. Also, the length, thickness and overlap of the internal and external balloons can be varied as necessary in one - specific application without deviating from the principles of the invention. Of course, one of the remarkable advantages of the present invention is that it has been available in a number hitherto unmatched by variations to combine the remarkable particularities of the various materials and thus for the adaptation of a balloon unit to an application specific in ways hitherto impractical or impossible. In addition, multiple luminous fluxes can be employed within the probe without deviating from the principles of the present invention which are frequently advantageous. For example, multiple luminous fluxes can provide the use of rigidity styles, guide wires for probe placement and irrigation or aspiration. Four preferred methods for the use of a double balloon superimposed probe will be described below. A first preferred method employs the superimposed double balloon probe of the present invention in an embolization or thrombectomy procedure. By endorsing Figures 3A to 3D, which illustrate the process that will be described below in a start sequence with Figure 3A and culminating with Figure 3D, a vessel 40 is held under an obstruction 41 and the probe 12 employing the balloon unit 10 described above with a deflated condition is placed in the vessel through an incision 44. The probe 12 is fed forward through the obstruction 41 and the balloon unit 10 is subsequently inflated to the clearance of the balloon. obstruction. The probe 12 is then pulled back against the obstruction, pulling the balloon unit 10 and the obstruction back to the incision site for removal. The balloon unit 10 of the present invention confers a number of advantages in a thrombectomy and embolectomy procedure. For example, the outer balloon 22 may employ a high surface friction material such as latex, while the inner balloon 14 may consist of a material that confers greater resistance to the balloon unit 10. The balloons of the prior art, consisting mainly of latex, used for thrombectomy and embolectomy are susceptible to rupture, even though the more sticky surface of the external balloon 14 of the latex is better able to seal against the vessel wall and better scrape the obstruction . Therefore, the present invention maintains the advantages of employing a latex balloon while overcoming its disadvantages. A second preferred method employs the superimposed double balloon probe of the present invention in an angioplasty procedure. Referring to Figures 4A to 4E, which illustrate the process described below in a sequence beginning with Figure 4A and culminating with Figure 4E, a guidewire 46 is placed within the vessel 40 through the incision 44. The guide wire is fed towards the vessel incision and is advanced beyond the stenosis area. The superimposed double balloon probe is then fed over the guide wire and placed in the stenotic area. The probe 12 to be used with the guidewire is typically a double luminous flux probe in which one of the luminous fluxes, to pass the guidewire, has an open distal tip, with the other luminous flux remaining in communication with the illumination unit. balloon to inflate the balloon. The probe is placed within the fluoroscopy aid in the stenosis area 47 formed of a stenotic material 49, typically a plate that adheres to the vessel wall so that the balloon unit 10 comes into contact with the area of the balloon. stenosis. The balloon unit is then inflated against the stenosis and thus pressed against the vessel wall. The vessel is thus opened in the area of stenosis by compression and partial crushing of the stenotic material. The subsequent balloon unit 10 deflates and the probe is withdrawn from the vessel through the incision. If the placement of the -stent, the wire is desired - guide 46 is typically left at the site in order to guide probe 12 as will be described below; however, this is not always required. The balloon unit 10 confers a number of advantages when employed in an angioplasty process. Typically, angioplasty balloons are relatively inelastic and when deflated, have the convolutions and bends described above. These convolutions and bends make it difficult to insert the balloon through the glass. In the taut outer balloon 22 of the present invention covers the convolutions and bends of a non-elastic but sturdy inner balloon 14, making the balloon unit 10 easier to insert. A third preferred method employs the double superimposed balloon probe of the present invention for stent placement, usually after an angioplasty procedure. Referring to Figures 5A to 5E, which illustrate the process as will be described below in a sequence beginning with Figure 5A and culminating with Figure 5E, the probe 12 is fed through the guide wire 46 through the incision 44 and the vessel 40. In this case, a double luminous flux probe is also used. A stent 48 is placed through the balloon unit 10 and a crimping device is used to compress the stent in position above it.

- The position of the probe is typically monitored either by X-ray or fluoroscopy and the proper position of the balloon unit 10 is confirmed in this manner. The balloon unit 10 is then inflated to expand the stent into place. The balloon unit 10 then deflates and the probe 12 is removed from the vessel 40 through the incision 44. The balloon unit 10 confers a number of advantages when starting in a stent placement procedure. For example, the compressible surface of the outer balloon 22 helps retain the stent in place during insertion, while the strong internal balloon 14 allows expansion thereof. A fourth preferred method employs the superimposed double balloon probe of the present invention for vessel or conduit occlusion. The probe 12 is inserted into a vessel or conduit and passed with or without a guidewire as needed, to a site to be occluded. The occlusion can be for prevention of blood flow during a surgical procedure as well as for the control of the movement of irrigation fluids, radiopaque dyes and for aspiration and removal of fluids, waste from ducts and stones. The balloon unit 10 confers a number of advantages when used for vessel or duct occlusion.For example, aortic occlusion requires the retention of - a probe balloon against very high pressure and blood flow. The balloon unit 10 in accordance with the present invention provides an ability to inflate to high pressures without breaking, and employs a coefficient of friction in order to resist eviction by very high blood flow and pressure, both contributing to retain the unit. balloon in its place. In addition, pronounced calcified arterial plaque can rupture a probe balloon, while balloon unit 10 in accordance with the present invention has increased puncture resistance. The terms and expressions that have been employed in the foregoing specification are used herein as terms of description and not of limitation, and are not intended to use these terms and expressions to exclude equivalents of the particularities shown and described and portions thereof. the same, it being recognized that the scope of the invention is defined and limited only by the claims that will be given below.

Claims (29)

- - CLAIMS:

1. A balloon probe comprising: a probe having a luminous flux therein; an internal balloon placed around a portion of the probe, the inner balloon has an outer surface and the probe has an opening therein for fluid communication between the luminous flux and the inner balloon; and an outer balloon having an inner surface the outer globe being positioned above the inner globe, a portion of the outer surface of the inner globe and the inner surface of the outer globe, being movable relative to each other.

The probe of claim 1, wherein the outer balloon and the inner balloon essentially overlap in a coextensive manner.

The probe of claim 1, wherein the inner balloon is fixed at the opposite ends circumferentially around the probe to form respective fluid-tight seals.

The probe of claim 3, wherein the outer balloon is fixed at the opposite ends circumferentially around the probe in order to form the respective fluid-tight seals.

The probe of claim 4, wherein the outer balloon is attached to the opposite ends around the respective opposite ends of the inner balloon.

6. The probe of claim 1, wherein the elasticity of the outer balloon is greater than the elasticity of the inner balloon.

The probe of claim 6, wherein the tensile strength of the inner balloon is greater than the tensile strength of the outer balloon.

The probe of claim 7, wherein the outer balloon provides surface friction higher than the inner balloon.

9. The probe of claim 1, wherein the tensile strength of the inner balloon is greater than the tensile strength of the outer balloon.

The probe of claim 1, wherein the outer balloon provides higher surface friction than the inner balloon.

11. The probe of claim 1, wherein an uninflated state, the outer balloon is under a predetermined amount of tension relative to the inner balloon.

12. The probe of claim 1, wherein the inner balloon comprises a polyethylene. -

13. The probe of claim 1, wherein the internal glove comprises polyethylene terephthalate.

The probe of claim 1, wherein the inner balloon comprises a nylon.

15. The probe of claim 1, wherein the inner balloon comprises a polyamide.

16. The probe of claim 1, wherein the inner balloon comprises polyvinyl chloride.

17. The probe of claim 1, wherein the outer balloon comprises a latex.

18. The probe of claim 1, wherein the outer balloon comprises a silicone.

19. The probe of claim 1, wherein the outer balloon comprises a thermoplastic elastomer.

20. A method for deploying a balloon unit in a balloon probe comprising an inner balloon having an outer surface and an outer balloon having an inner surface, the outer balloon being positioned almost at the top of the inner balloon where the internal surface of the external balloon is movable with respect to the external surface of the inner balloon, where the internal balloon remains in fluid communication with the luminous flux of inflation, the method comprises: - - introduce a fluid in the internal balloon through the luminous flux of inflation causing an expansion of the internal balloon; and expand the outer globe by expanding the inner globe.

21. A method for constructing a balloon probe comprising: placing an internal balloon through a probe having a luminous flux and no lateral opening through the probe for fluid communication with the luminous flux; fixing the opposite ends of the inner balloon on opposite sides of the opening to the tube in order to form a fluid-tight seal; placing an external balloon above the inner balloon to remain under a predetermined amount of tension; and fix the opposite ends of the outer globe while they are still in tension, in the probe.

22. The method of claim 21, wherein the opposite ends of the outer globe are positioned above the respective opposite ends of the inner balloon and fixed therewith.

23. The method of claim 22, wherein the opposite ends of the outer balloon are fixed in order to form a fluid-tight seal.

24. A method for removing an obstruction in a blood vessel, comprising the steps of: inserting into the blood vessel an inflatable balloon unit having an inner balloon and an outer balloon positioned almost on top of the inner balloon, the balloon internal comprises a relatively strong and non-elastic material and the outer balloon comprises a taut material having a high surface friction characteristic, the balloon unit being essentially deflated; feed the balloon unit through the obstruction; inflate the balloon unit; and retracting the balloon unit from the vessel, to remove the obstruction from the vessel.

25. A method for releasing a stenosis site in a blood vessel formed by a stenosis material comprising the steps of: inserting into the blood vessel an inflatable balloon unit having an internal balloon and an external balloon positioned essentially at the top of the blood vessel. inner balloon, the inner balloon comprises a non-elastic and relatively strong material and the outer balloon comprises a taut material having a relatively high surface friction characteristic, the balloon unit being essentially deflated; feed the balloon unit to the estonosis area and place the balloon unit in it; and inflating the balloon unit, to compress the stenotic material forming the stenosis and in this way to release the stenosis area.

26. The method of claim 25, further comprising before inserting the balloon unit into the blood vessel, inserting a guide wire into the blood vessel and placing the guidewire in the stenosis site, and wherein the feeding it is carried out by placing the balloon unit over the guidewire and using the guidewire to guide the balloon unit towards the area of stenosis.

27. A method for placing a stent at a selected position in a blood vessel, comprising the steps of: placing the stent through an inflatable balloon unit having an internal balloon and an external balloon essentially placed on top of the inner balloon, the inner balloon comprises a relatively strong and non-elastic material and the outer balloon comprises a taut material having a relatively high surface friction characteristic; flange the stent in position above the balloon unit to hold the stent in place; insert the balloon unit into the blood vessel; feeding the balloon unit to the selected position in the blood vessel; inflate the balloon unit to expand the stent into place; deflate the balloon unit; and removing the balloon unit from the expanded stent.

The method of claim 27, further comprising, before inserting the balloon unit into the blood vessel, inserting a guide wire into the blood vessel where the feeding is carried out by placing the balloon unit above the blood vessel. guide wire and using the guide wire to guide the balloon unit to the selected position.

29. A method for occluding a vessel or duct comprising the steps of: inserting into the conduit or blood vessel a probe having an inflatable balloon unit having an internal balloon and an external balloon essentially placed on the upper part of the inner balloon , the inner balloon - - comprising a relatively strong non-elastic material that provides improved puncture resistance and high pressurization capacity, the outer balloon comprises a taut material having a relatively high surface friction characteristic to hold the balloon unit in place against the pressures of elevated body fluid; and inflating the balloon unit by introducing a fluid into the internal balloon through the luminous flux of inflation to occlude the vessel or conduit.