Method and apparatus for minimizing excess drug delivery

Abstract

To provide a device and method for aspirating within a patient during the delivery of a drug-coated treatment device to help remove drug coating dislodged in a patient's blood.SOLUTION: A vascular treatment system 120 comprises a balloon catheter 121 and a guide catheter 130. The balloon catheter 121 includes an elongated body 122, a drug-coated balloon 126 connected near the distal end of the elongated body 122, and a drug coating 128 disposed on the drug-coated balloon 126. The guide catheter 130 includes an elongated tubular body having a guide catheter lumen therein, and an aspirating port 132 connected to the guide catheter lumen and configured to be connected to a vacuum source. The guide catheter 130 is configured to aspirate blood in the vicinity of the drug-coated balloon 126 during a treatment procedure.SELECTED DRAWING: Figure 3

Description

Related Applications

[0001] This application claims the benefit of and priority to U.S. Provisional Application No. 62 / 950,039, filed December 18, 2019, entitled "Minimizing Drug Deposition During Drug Delivery Procedures," which is incorporated herein by reference in its entirety. [Background technology]

[0002] Various vascular procedures utilize drug-coated devices to deliver drugs or similar substances to specific areas of tissue within a patient's body. These drugs are often used to treat or prevent stenosis, restenosis, sclerosis, or similar vascular diseases.

[0003] In one example, a balloon catheter can be used for this purpose. The balloon of the catheter contains a drug coating on its outer surface, and when inflated, it presses the drug coating against the inner surface of the blood vessel, thereby applying at least a portion of the drug coating to the contacted tissue. In another example, a stent contains a drug coating on its surface, and the drug is applied to the blood vessel tissue that the stent contacts when expanded, allowing the drug to be absorbed by the tissue.

[0004] While drug coatings on such devices remain an important method of drug delivery to targeted areas of the vasculature, a significant portion of the drug coating can become detached or released during the delivery procedure, which can migrate to many unintended locations within the patient's blood and vasculature, thereby causing undesirable complications for the patient.

[0005] For example, paclitaxel may be incorporated into a drug coating on a balloon catheter to treat restenosis or vascular stenosis. Paclitaxel is particularly well-suited for application via a balloon catheter due to its high concentration and rapid release from the coating. However, treatment with paclitaxel via a balloon or stent is also associated with an increased risk of mortality. One possible cause of this increased mortality is that paclitaxel may be released into the patient's bloodstream and migrate to organs that are particularly sensitive to the drug, such as the lungs. In treatments with relatively high concentrations of paclitaxel in the drug coating, measurable levels of paclitaxel may remain in the patient's blood for 30 days or more.

[0006] Unintended drug release from drug coatings is further complicated by the properties of the coating itself. If the coating is resistant to detachment from the device, very little drug will be released into the patient's tissues. If the coating detaches easily, most of the drug may circulate within the patient's vascular system. Thus, delivery of a desired amount of drug using such coatings will often entail the release of some, or a significant, portion of the drug into the bloodstream.

[0007] In fact, applicants have conducted experiments and analyses and obtained the following statistics: While less than 1% of the drug is transferred from a typical balloon coating to the target tissue area, only about 16% of the coating remains on the balloon after the procedure is complete. Approximately 25% of the drug coating detaches during guiding the balloon catheter through the guide catheter, and approximately 59% of the drug coating detaches during inflation, deflation, and removal of the balloon from the catheter. As a result, it is believed that approximately 84% of the drug coating detaches from the balloon during the procedure and disperses throughout the patient's vasculature and organs. Depending on the type of drug coating, the concentration of the drug in the coating, and the type of balloon (or other device), significant amounts of the drug can often be measured in the patient's blood for a period of time following treatment.

[0008] For at least these reasons, there is a need for improved treatment methods and devices that reduce the amount of drug that is unintentionally released into a patient's bloodstream during treatment. Summary of the Invention

[0009] At least one embodiment is directed to a device for providing suction within a patient's body during delivery of a drug-coated therapeutic device to assist in removing drug coating that has shed into the patient's blood. The drug-coated therapeutic device can be a drug-coated balloon, a drug-coated stent, or similar device.

[0010] At least one embodiment is directed to a treatment system and method of use that generates suction near a distal portion of a drug-coated treatment device, near a proximal portion of a drug-coated treatment device, or both locations. The suction can be generated during distal advancement of the delivery device within the patient's vasculature, during radial expansion / implantation of the drug-coated treatment device, during proximal withdrawal of the drug-coated treatment device, and / or at any time in between or near these time periods.

[0011] At least one embodiment is directed to a method and treatment system having a balloon catheter with a proximal drug-coated balloon configured to expand against a blood vessel and a distal occlusion balloon configured to occlude the blood vessel. The treatment system may further include a guide catheter (or alternatively, a guide or introducer sheath) configured to aspirate material from its distal end during a procedure.

[0012] At least one embodiment is directed to a method and treatment system including a balloon catheter with a sequentially inflated balloon. The balloon has a distal portion that inflates first, which generally lacks a drug coating, and a proximal portion that inflates second, which includes a drug coating. The treatment system may further include a guide catheter (or alternatively, a guide sheath or introducer sheath) configured to aspirate material from its distal end during a procedure.

[0013] At least one embodiment is directed to a method and treatment system including a balloon catheter with a drug-coated balloon and a guidewire lumen configured to apply suction from the distal end of the balloon catheter. The guidewire lumen may have a relatively large diameter and be connectable to a suction source. The balloon catheter may optionally be used with a proximally disposed occlusion balloon and / or a guide catheter (or alternatively, a guide sheath or introducer sheath) configured to apply suction.

[0014] At least one embodiment is directed to methods and treatment systems having a balloon catheter with an aspiration passageway extending through the drug-coated balloon and selectively connected to a guide catheter (or alternatively, a guide sheath or introducer sheath) capable of generating aspiration. The guide catheter can be configured to generate aspiration, with its distal end connectable to the aspiration passageway to allow aspiration distal to the drug-coated balloon. Optionally, an occlusion balloon can be advanced through the aspiration passageway and used distal to the drug-coated balloon. [Brief explanation of the drawings]

[0015] These and other aspects, features, and advantages enabled by practices of the present invention will be apparent and made clear from the following description of embodiments of the invention, which proceeds with reference to the accompanying drawings.

[0016] [Figure 1] FIG. 1 is a side view of a balloon catheter.

[0017] [Figure 2] FIG. 1 is a side view of a balloon catheter within a guide catheter.

[0018] [Figure 3] FIG. 1 is a side view of a dual balloon catheter within a guide catheter.

[0019] [Figure 4] FIG. 4 is a side view of the dual balloon catheter of FIG. 3.

[0020] [Figure 5] FIG. 1 is a side view of a sequentially inflatable balloon catheter.

[0021] [Figure 6] FIG. 6 is a side view of the sequentially inflatable balloon catheter of FIG. 5.

[0022] [Figure 7] FIG. 6 is a side view of the sequentially inflatable balloon catheter of FIG. 5.

[0023] [Figure 8] FIG. 6 is a side view of the sequentially inflatable balloon catheter of FIG. 5.

[0024] [Figure 9] FIG. 6 is a side view of the sequentially inflatable balloon catheter of FIG. 5.

[0025] [Figure 10] FIG. 6 is a side view of the sequentially inflatable balloon catheter of FIG. 5.

[0026] [Figure 11] FIG. 1 is a side view of a balloon catheter having an enlarged guidewire passage.

[0027] [Figure 12] FIG. 12 is a side view of the balloon catheter of FIG. 11.

[0028] [Figure 13] FIG. 12 is a side view of the balloon catheter of FIG. 11.

[0029] [Figure 14] FIG. 1 is a side view of a balloon catheter.

[0030] [Figure 15] FIG. 15 is a side view of the balloon catheter of FIG. 14 with a guide catheter and an occlusion catheter. DETAILED DESCRIPTION OF THE INVENTION

[0031] Specific embodiments of the present invention will be described below with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The terminology used in the detailed description of the embodiments shown in the accompanying drawings is not intended to be limiting of the invention. In the drawings, like numbers refer to like elements. Although various embodiments are described, the features of each embodiment can be substituted for and used in other described embodiments. In other words, any of the features of the embodiments can be mixed and matched with each other, and the embodiments should not necessarily be construed strictly as including only the features shown or described.

[0032] As used herein, the terms drug and drug coating are intended to include any therapeutic agent, compound, chemical, or other substance that can be included in a coating on a device.

[0033] As previously mentioned, drug-coated devices, such as balloon catheters and stents, often release undesirable amounts of their drug coating into the blood during therapeutic procedures, which then circulates through the patient's vascular system. Much of this undesirable drug release can occur during guiding the device (e.g., balloon or stent) through an outer guide catheter, during expansion of the device within the patient's blood vessel, during deflation of the device, and during retraction back into the guide catheter.

[0034] One example of this undesirable loss of drug coating can be seen in Figures 1 and 2. Figure 1 shows a typical balloon catheter 100 having a drug-coated balloon 106 disposed at the distal end of an elongated catheter body 102. The catheter body 102 also includes a guidewire passageway 104 opening proximally and distally to the balloon 106, as well as a balloon inflation lumen (not shown) that communicates between the interior of the balloon 106 and a proximal catheter hub 108 to allow inflation of the balloon. This guidewire passageway 104 configuration is commonly referred to as a rapid exchange catheter, although over-the-wire catheters with a guidewire passageway opening at the proximal end of the catheter are also contemplated.

[0035] 2, the balloon catheter 100 is typically advanced out of the overlying guide catheter 110 to position the drug-coated balloon 106 adjacent to the vessel wall of the target treatment area. An inflation medium is injected into the inflation lumen to inflate the drug-coated balloon 106 into contact with the vessel wall and deliver at least a portion of the drug coating to the vessel wall. Finally, the drug-coated balloon 106 is deflated and retracted into the overlying guide catheter 110. It should be understood that although a guide catheter is used throughout this specification, a guide sheath or introducer sheath may be used in place of this component throughout this specification.

[0036] As shown in Figure 2, a large portion of the drug coating 109 is released from the balloon 106 during the treatment procedure, mixes with the patient's blood, and circulates through at least a portion of the patient's vascular system and organs, such as the heart and lungs. Depending on the type of drug, the amount released from the balloon, the treatment location, and other factors, significant and undesirable concentrations of the drug may remain in the patient's blood and / or organs for days or even weeks after the treatment procedure.

[0037] This specification describes several therapeutic devices and methods for inhibiting the undesired accumulation of drugs that have broken away from the coating of a therapeutic device. While various embodiments of balloon catheters are described primarily, it should be understood that the devices and methods of the present invention may be similarly adapted for use with other drug-coated devices, such as stents, or even with uncoated devices that deliver drugs directly to a target area (e.g., weeping balloons configured to expel drugs through their pores).

[0038] 3 and 4 illustrate one embodiment of a treatment system 120 configured to aspirate or remove at least a portion of a drug coating released into a patient's vasculature during a treatment procedure. Treatment system 120 includes a balloon catheter 121 having an occlusion balloon 124 configured to occlude a distal portion of a target blood vessel of the patient prior to inflation of a drug-coated balloon 126. As described in more detail below, blood containing the drug coating that becomes detached or released during the treatment is aspirated and removed from the patient to prevent it from circulating through the patient's blood vessels.

[0039] Occlusion balloon 124 is located distal to drug-coated balloon 126 on elongate body 122 of balloon catheter 121. Balloons 124, 126, and elongate body 122 are configured so that occlusion balloon 124 is fully inflated before significant inflation of drug-coated balloon 126, and deflated after deflation of drug-coated balloon 126. This inflation sequence is effective in maintaining the vessel occluded during the portion of the procedure when the drug coating is most likely to be released into the patient's bloodstream; for example, occlusion balloon 124 is effective in preventing distal migration of drug from drug-coated balloon 126 and / or in providing a seal for a subsequent aspiration procedure, as will be described in more detail. In one example, this inflation sequence can be achieved using two separate inflation lumens within elongate body 122, each of which is connected to a separate inflation lumen and inflation port (e.g., port 123A and port 123B) at the proximal end of elongate body 122.

[0040] In another example, both balloons 124, 126 may be connected to a single inflation lumen within body 122. To create the desired inflation sequence, occlusion balloon 124 may be constructed of a material that is easier to expand than drug-coated balloon 126. In one example, occlusion balloon 124 may be constructed of a relatively inelastic material that increases in diameter with little resistance (e.g., similar to inflating a plastic bag), while drug-coated balloon 126 may be constructed of a relatively elastic material that stretches during inflation to provide resistance (e.g., similar to a rubber party balloon). Thus, as pressure increases within the inflation lumen, occlusion balloon 124 expands first, followed by drug-coated balloon 126, and drug-coated balloon 126 deflates first, followed by occlusion balloon 126.

[0041] In any of the balloon inflation examples described above, the proximal end (e.g., catheter hub) of the elongate body 122 may be connected to one or more syringes that are manually operated to cause inflation, or to a powered inflation device. In the case of a powered inflation device, it may be desirable to provide and maintain various pressure levels within the inflation lumen and the balloons, particularly in the single inflation lumen example described above, since different levels of pressure within the inflation lumen determine the sequence of inflation of the two balloons 124, 126 (e.g., low pressure to inflate only the occlusion balloon 124, and high pressure to also inflate the drug-coated balloon 126). In this regard, the powered inflation device may include an algorithm configured to provide a predetermined sequence of pressure levels to achieve a desired sequence of balloon inflation and deflation.

[0042] As previously described, the treatment system 120 is configured to apply suction to remove blood adjacent the drug-coated balloon, including any shed drug coating 128. In this embodiment, this suction can be applied via an outer guide catheter 130 or sheath through which the balloon catheter 121 is disposed. The guide catheter 130 may have a generally tubular body and may include a suction port 132 opening into the inner lumen of the guide catheter 130 so that a vacuum source, such as a syringe 136 or pump, can be connected thereto. When the vacuum source is activated, blood is drawn from the distal end of the guide catheter 130 into its lumen and toward the vacuum source. The guide catheter typically includes a hemostatic valve at its proximal end (e.g., surrounding the balloon catheter 121) to prevent air from being drawn into the lumen of the guide catheter 130. In other words, the guide catheter 130 is configured to only allow suction from its distal end toward the vacuum source, not from its proximal end. In this embodiment, continuous occlusion of the blood vessel is effective in preventing detached drug particles from migrating through the patient's vasculature before the guide catheter 130 can aspirate them from the patient.

[0043] When using a syringe 136 as a vacuum source, the physician may initially maintain a stopcock valve 134, located between the syringe 136 and the guide catheter 130, in a closed position. The plunger of the syringe 136 can be pulled back to create negative pressure, and then the stopcock valve 134 can be opened when aspiration is desired within the patient. Blood from the area adjacent the drug-coated catheter 126 is then drawn into the guide catheter 130 and then into the syringe 136. Various amounts of blood may be drawn based on the location of the procedure, the characteristics of the drug coating, and other factors. In many cases, a 30cc or 60cc syringe or aspiration volume may be appropriate.

[0044] In one example, treatment system 120 can be used by first advancing a guidewire into the patient's vasculature until its distal end is positioned near the desired treatment location within the blood vessel. Next, guide catheter 130 can be advanced over the guidewire until its distal end is positioned near the desired treatment location. Balloon catheter 121 is then advanced through guidewire passage 122A and over the guidewire to position drug-coated catheter 126 at the desired target location and occlusion balloon 124 distal to the target location. If desired, the guidewire can be retracted before inflation of balloons 124, 126.

[0045] The occlusion balloon 124 is then inflated to occlude the blood vessel and substantially prevent blood from flowing therethrough. Once the blood vessel is occluded, the drug-coated balloon 126 is inflated, causing the drug coating 128 thereon to contact the inner surface of the blood vessel, and the drug coating is delivered or applied to the tissue of the blood vessel, as shown in Figure 3.

[0046] As previously mentioned, the process of tracking the balloon catheter 121 through the guide catheter 130, the process of inflating the drug-coated balloon 126, the process of deflating the drug-coated balloon 126, and other movements during the procedure can result in the detachment or release of a significant portion of the drug coating 128. In this regard, as the drug-coated balloon 126 is deflated (partially or fully), the physician can apply suction through the guide catheter 130. Note that suction may be applied throughout the entire movement and inflation process. Again, such suction can be generated by, among other methods, opening a valve 134 connected to a syringe 136 with its plunger retracted.

[0047] As shown in FIG. 4 , blood and detached drug coating 128 are drawn into guide catheter 130, out port 132, and into syringe 136 (although some blood and some of the drug coating may remain within guide catheter 130). In one example, the physician may remove 30-60 milliliters of blood from the area between occlusion balloon 125 and the distal end of guide catheter 130. Eventually, drug-coated balloon 126 is fully deflated (if not already fully deflated), and occlusion balloon 124 is also fully deflated, allowing the physician to withdraw balloon catheter 121 proximally back into guide catheter 130 to complete the procedure. Thus, much of the detached drug coating that would otherwise circulate in the patient's vasculature is removed from the patient.

[0048] 5-10 show another embodiment of a balloon catheter 140 having a single sequentially inflatable balloon 146 that can be first partially inflated to occlude a portion of a patient's blood vessel and then fully inflated to deliver a therapeutic agent to the tissue of the vessel. As with the balloon catheter 121 described above, this allows for the occlusion of a portion of a patient's blood vessel to prevent the migration of shed drug, and then allows for the removal of some of the shed drug from the patient's blood by aspiration.

[0049] As shown in Figures 5 and 6, the balloon catheter 140 comprises an elongate body 142 having a guidewire passage 144 (e.g., a rapid exchange, monorail-type guidewire passage) extending through at least a distal portion thereof, and a balloon 146 disposed near the distal end of the elongate body 142.

[0050] A drug coating is disposed on balloon proximal portion 146B to allow delivery of the drug to the patient's blood vessel, while balloon distal portion 146A contains little or no drug coating, such that balloon distal portion 146A is able to expand to occlude the blood vessel with little, if any, drug coating migrating distally from catheter 140.

[0051] 7-10, balloon catheter 140 is configured to sequentially inflate and deflate balloon distal portion 146A and balloon proximal portion 146B. Specifically, balloon distal portion 146A is inflated first, followed by balloon proximal portion 145B, and balloon distal portion 146A is deflated, followed by balloon proximal portion 145B.

[0052] This sequential inflation of the balloons can be achieved in several different ways. For example, each portion 146A, 146B of the balloon 146 can be constructed of a material that causes the distal balloon portion 146A to inflate (i.e., is easier to inflate) at a lower pressure than the proximal balloon portion 146B. This difference in resistance to inflation between the two portions 146A, 146B can be achieved by constructing different materials, different material thicknesses, an additional layer / strip of material over the proximal balloon portion 146B, any combination of these techniques, or similar techniques. Alternatively, the elongate body 142 can include a single inflation lumen in communication with the balloon 146 to enable this inflation / deflation sequence. As with the previous embodiment, the inflation mechanism can be a manually actuated device, such as a syringe, or a powered inflation device that can be programmed to achieve and maintain the specific desired pressure required for sequential inflation.

[0053] In another example, balloon 146 may include a mechanism for pumping inflation media to balloon distal portion 146A and balloon proximal portion 146B at different rates to create sequential inflation. This can be achieved using larger distal and smaller proximal inflation ports on elongate body 142 inside balloon 146, a partial or complete wall within the balloon separating the two portions 146A, 146B, distal and proximal inflation ports with valves that open by different amounts, separate inflation lumens within elongate body 142, or a combination of these features.

[0054] Balloon catheter 140 can be used in the following exemplary procedure: First, a guidewire is advanced within a patient's body, and its distal end is positioned near a target region of the patient's blood vessel. Next, an elongated, tubular guide catheter 148 is advanced over the guidewire, and its distal end is positioned proximal to the target region. Next, balloon catheter 140 is advanced over the guidewire and through the inner lumen of guide catheter 148, and its distal end and balloon 146 are positioned at the target region of the patient's blood vessel. Preferably, distal portion 146A is positioned distal to the target region, while drug-coated proximal portion 146B is positioned circumferentially within the target region of the blood vessel.

[0055] Referring to Figure 7, the distal portion 146A of the balloon 146 is first inflated to completely or substantially occlude the blood vessel. As shown in Figure 8, the drug-coated proximal portion 146B is inflated, expanding its drug-coated surface against the target area of ​​the blood vessel to dispense or deliver a portion of the drug.

[0056] 9, when the balloon proximal portion 146B is partially or fully deflated, the detached drug coating 143 remains in the blood trapped near the balloon 146. At this point, suction is applied through the guide catheter 148, although suction can be applied earlier. This suction can be applied in a similar manner and with similar devices as described above for the guide catheter 130.

[0057] Finally, the balloon 146 can be fully inflated and withdrawn into the guide catheter 148 to complete the procedure, as shown in Figure 10. Suction may be continued during this full deflation and balloon withdrawal, if desired, to further remove any drug coating that may have detached.

[0058] 11-13 show another embodiment of a balloon catheter 150 configured to apply suction through its distal end to assist in removing a portion of the shed drug coating 156. Such distal suction can optionally be used in conjunction with suction proximal to the balloon 154 from a guide catheter (such as guide catheter 130 and guide catheter 148 described above).

[0059] The balloon catheter 150 may include an elongate body having a guidewire passageway extending therethrough that is configured to also function as an aspiration passageway. The passageway has a proximal opening 157 in the catheter hub 151 to allow a guidewire to enter the passageway, and may have a distal opening 158 to allow the guidewire to exit the passageway. The catheter hub 151 may have an aspiration port 153 that also communicates with the guidewire passageway and is connectable to a vacuum source, such as the syringe 136. A hemodynamic valve in the proximal portion of the guidewire passageway seals the proximal end of the passageway, such that application of negative pressure to the guidewire passageway results in aspiration or suction through the distal opening 158 of the balloon catheter 150.

[0060] Optionally, the guidewire passageway has a somewhat larger diameter than typical guidewire passageways to prevent clogging during aspiration and ensure that aspiration removes blood at a desired rate. In one example, the guidewire / aspiration passageway diameter ratio relative to the inflated balloon 154 is in the range of approximately 0.2 to 0.8. Some example ratios and measurements for prior art guidewire lumens and the larger guidewire passageway sizes according to this embodiment are shown in Table 1 below. For example, a guidewire lumen with a 0.036 mm diameter size and a 2 mm balloon diameter size results in a ratio of 0.18, while a 1.22 mm balloon diameter and a 2 mm balloon diameter results in a ratio of 0.61.

[0061] Table 1 JPEG2025131605000002.jpg69166

[0062] Balloon catheter 150 can be used in the following exemplary procedure: First, a guidewire is advanced within a patient's body until its distal end is positioned near a target region of the patient's blood vessel. Next, an elongated, tubular guide catheter (similar to guide catheter 130 or guide catheter 148) is advanced over the guidewire until its distal end is positioned near the target region. Next, balloon catheter 150 is advanced over the guidewire and through the inner lumen of the guide catheter until its distal end and balloon 154 are positioned at the target region of the patient's blood vessel.

[0063] 12, the balloon 154 is inflated so that its drug coating 156 is pressed against the tissue in the target area. While the balloon 154 is advanced out of the guide catheter and inflated, suction from the guide catheter (as described for previous embodiments) and / or suction from the distal opening 158 of the guidewire lumen can be used to help collect any drug coating 156 that detaches during this time.

[0064] 13, balloon 154 can be deflated after a desired period of contact with the target area. This deflation may result in the detachment of additional drug coating (shown in the blood as elements 159), so additional suction is effective to capture and aspirate drug particles and blood from the distal end of catheter 150. Suction in this embodiment may be solely through distal opening 158 or may be combined with suction from the guide catheter at various times throughout the procedure.

[0065] When applying suction from both the distal opening 158 and the guide catheter, it may be desirable to apply different negative pressures from each source depending on how strong the intended suction should be. For example, it may be desirable to use a smaller, more gentle negative pressure from the distal opening 158 to prevent collapse of the patient's blood vessel, while a stronger vacuum source from the guide catheter is less likely to cause collapse of the blood vessel by the balloon catheter extending distally out of the opening in the guide catheter.

[0066] 14 and 15 illustrate another embodiment of a treatment system capable of selectively applying suction proximally and distally to a drug-coated balloon 162 during a procedure. Specifically, a drug-coated balloon catheter 160 is configured to couple, or sealingly engage, with a distal opening of a guide catheter 130 that is connected to a suction source. This configuration allows the guide catheter 130 to apply suction proximally to the balloon 162 when detached from the balloon 162, and to apply suction distally to the balloon 162 via a passageway 164 when engaged with the proximal end of the balloon 162, as shown in FIG. 15 .

[0067] In one embodiment, the drug-coated balloon catheter 160 comprises an elongate catheter body 168 connected at its distal end to an enlarged tubular portion having a passageway 164. The balloon 164 is connected to the enlarged tubular portion and is configured to be inflated via an inflation lumen within the elongate catheter body 168.

[0068] The balloon 162 is configured to inflate such that the distal balloon portion 162A has a larger inflated diameter and the proximal balloon portion 162B has a relatively smaller inflated diameter. The inflated diameter of the distal balloon portion 162A is preferably large enough to contact the inner circumferential surface of the target vessel to deliver a portion of its drug coating 166. The inflated diameter of the proximal balloon portion 162B is approximately the same size as the inner diameter of the inner lumen of the guide catheter 130 (e.g., slightly larger, equal to, or slightly smaller than the inner lumen). This size allows the inflated proximal balloon portion 162B to fit and lock inside the guide catheter 130. Thus, when suction is applied to the guide catheter 130, the suction is directed through the proximal opening 164A of the passageway 164 and out the distal opening 164B. Alternatively, the balloon proximal portion 162B may expand in a conical or tapered shape, increasing in size distally so as to "wedge" into the inner lumen of the guide catheter 130.

[0069] Optionally, the passageway 164 has a diameter large enough to accommodate an occlusion balloon catheter 170 passing therethrough to occlude a region of the blood vessel distal to the balloon 162, similar to the previous embodiment. In one example, the passageway 164 has a diameter to accommodate a 0.014 inch (0.035 cm) balloon. Accordingly, the balloon may have an inner diameter of approximately 0.050 inch (0.13 cm). In this regard, the passageway 164 may have a diameter that provides sufficient clearance around the body 172 of the balloon catheter 170 so that suction can occur through the passageway 164 while the balloon catheter 170 is within the passageway 164.

[0070] Balloon catheter 160 can be used in the following exemplary procedure: First, guidewire 111 is advanced within the patient until its distal end is positioned near a target area of ​​the patient's blood vessel. Next, elongated tubular guide catheter 130 is advanced over guidewire 111 until its distal end is positioned proximate the target area. Next, drug-coated balloon catheter 160 is advanced over the guidewire (through passageway 164) and through the inner lumen of guide catheter 130 until its distal end and balloon 162 are positioned at the target area of ​​the patient's blood vessel.

[0071] Optionally, an occlusion balloon catheter 170 is advanced over the guidewire 111 and through the passageway 164 of the drug-coated balloon catheter 160. The occlusion balloon 174 is then inflated to contact and occlude a region of the patient's vessel distal to the region of interest. Such a configuration can be seen in FIG. 15.

[0072] The balloon 162 of the drug-coated catheter 160 is then inflated so that the drug coating 166 on the balloon's distal portion 162A contacts the target area of ​​the patient's blood vessel, while the distal end of the guide catheter 130 may be positioned proximally away from the balloon 162, and suction may be applied in the manner previously described for other embodiments.

[0073] The distal end of guide catheter 130 can then be moved distally toward balloon 162 so that its lumen surrounds and overlaps smaller diameter portion 162B of balloon 162. Suction through guide catheter 130 is then activated, if not already activated, to create suction in the space between occlusion balloon 174 (if present) and drug-coated balloon 162. Thus, any loose drug coating present in the blood between the two balloons 162, 174 is partially or completely removed.

[0074] Once the desired amount of suction has been achieved, the drug-coated balloon 162 is deflated and retracted into the guide catheter 130. Similarly, the occlusion balloon 174 can be deflated and retracted into the guide catheter 130 to complete the procedure.

[0075] In alternative embodiments, any of the drug-coated balloons and / or occlusion balloons of the previous embodiments may be replaced with a non-distensible device, such as an expandable mesh device.

[0076] In an alternative embodiment, the drug-coated balloon and balloon catheter of the previous embodiment may be replaced with a drug-coated stent (or similar implantable device) and stent delivery catheter.

[0077] In an alternative embodiment, the drug-coated balloon and balloon catheter of the previous embodiment can be replaced with a balloon catheter having a balloon that "wets" or slowly releases liquid drug from pores in the surface of the balloon.

[0078] The procedure described in this embodiment may be performed at many different locations in a patient's vascular system, but may be particularly useful for treatments in the arms, legs, and torso.

[0079] While the present invention has been described with respect to particular embodiments and applications, those skilled in the art will be able to generate further embodiments and modifications in light of the present teachings without departing from the spirit or scope of the claimed invention. Accordingly, it should be understood that the drawings and descriptions herein are provided by way of example to facilitate understanding of the invention and should not be construed as limiting the scope of the invention.

Claims

1. A vascular treatment system including a balloon catheter and a guide catheter, The balloon catheter A long, slender body and a drug-coated balloon connected to the elongate body near the distal end; a drug coating disposed on the drug-coated balloon; The guide catheter an elongated tubular body having a guide catheter lumen therein; a suction port connected to the guide catheter lumen and further configured for connection to a vacuum source; the guide catheter is configured to aspirate blood adjacent the drug-coated balloon during a therapeutic procedure. Vascular treatment system.

2. 2. The vascular treatment system of claim 1, wherein the balloon catheter further comprises an occlusion balloon connected to the elongate body distal to the drug-coated balloon, and the balloon catheter is configured to first inflate the occlusion balloon and then inflate the drug-coated balloon.

3. The vascular treatment system of claim 2 , wherein the balloon catheter is configured to first deflate the drug-coated balloon and then deflate the occlusion balloon.

4. The drug-coated balloon comprises: a distal portion; and a proximal portion; the drug coating is disposed on the proximal portion, and the drug-coated balloon is configured to first inflate the distal portion and then inflate the proximal portion. The vascular treatment system according to claim 1 .

5. 5. The vascular treatment system of claim 4, wherein the distal portion is configured to inflate before the proximal portion by one or more of the following: a variation in balloon thickness; a reinforcing band; use of different balloon materials between the proximal and distal portions; and different inflation opening sizes between the proximal and distal portions.

6. 5. The vascular treatment system of claim 4, wherein the balloon catheter includes a guidewire passage opening distal to the drug-coated balloon, the guidewire passage configured to connect to a suction source to apply suction at the opening of the guidewire passage.

7. 2. The vascular treatment system of claim 1, wherein the balloon catheter includes a guidewire passage opening distal to the drug-coated balloon, the guidewire passage configured to connect to a suction source to apply suction at the opening of the guidewire passage.

8. 8. The vascular treatment system of claim 7, wherein the ratio of the diameter of the inflated drug-coated balloon to the diameter of the guidewire passage is within the range of about 0.2 to 0.

8.

9. 2. The vascular treatment system of claim 1, wherein the drug-coated balloon has a distal portion in which the drug coating is disposed and a proximal portion sized for a diameter when fully inflated to fit and lock into the guide catheter lumen.

10. 10. The vascular treatment system of claim 9, further comprising an occlusion catheter configured to advance distally through a passageway of the balloon catheter and occlude a blood vessel distal to the drug-coated balloon.

11. 1. A method of vascular treatment, comprising: advancing a guide catheter adjacent a target location within a patient; advancing a drug-coated balloon of a balloon catheter out of the distal end of the guide catheter; inflating the drug-coated balloon to deliver the drug to the target site; removing at least a portion of the drug that has detached from the drug-coated balloon by applying suction adjacent the drug-coated balloon; A method for providing the above.

12. 12. The method of claim 11, wherein suction near the drug-coated balloon is achieved through a distal end of the guide catheter connected to a suction source.

13. 13. The method of claim 12, further comprising inflating an occlusion balloon distal to the drug-coated balloon before inflating the drug-coated balloon.

14. Inflating the drug-coated balloon includes: inflating a distal portion of the balloon catheter to occlude a blood vessel near the target location; Next, inflating a proximal portion of the balloon having the drug coating against the target site. The method of claim 11 further comprising:

15. 15. The method of claim 14, wherein suction near the drug-coated balloon is performed through the distal end of the guide catheter.

16. 12. The method of claim 11, wherein suction near the drug-coated balloon is performed through a distal opening of a lumen in the balloon catheter.

17. 12. The method of claim 11, wherein the step of suctioning near the drug-coated balloon comprises advancing the guide catheter distally so that at least a portion of a proximal portion of the drug-coated balloon is located within the lumen of the guide catheter, and the suction occurs distal to the drug-coated balloon.

18. 18. The method of claim 17, wherein an occlusion balloon is inflated distal to the drug-coated balloon prior to inflating the drug-coated balloon.

19. A vascular treatment kit including a balloon catheter and a guide catheter, The balloon catheter A long, slender body and a drug-coated balloon connected to the elongate body near the distal end; a drug coating disposed on the drug-coated balloon; The guide catheter an elongated tubular body having a guide catheter lumen therein; a suction port connected to the guide catheter lumen and further configured for connection to a vacuum source; the guide catheter is configured to aspirate blood adjacent the drug-coated balloon during a therapeutic procedure. Vascular treatment kit.

Images