WO2025160241A1 - Thermal balloon catheter (tbc) for biocarpet deployment and thermal angioplasty - Google Patents

Abstract

The invention relates to a thermal balloon catheter that includes a catheter, one or more balloons, and optionally a flexible, biodegradable endovascular medical implant device, e.g., a biocarpet device. The thermal balloon catheter is effective for deployment of the biocarpet device, or performing thermal angioplasty (in the absence of the biocarpet device). In one embodiment of the invention, a method of deploying a flexible, biodegradable endovascular medical implant device, e.g., biocarpet device, in a target vascular region includes forming a thermoformed structure, e.g., tube or cylinder, that can conform to the geometry or anatomy of the target vascular region.

Description

THERMAL BALLOON CATHETER (TBC) FOR BIOCARPET DEPLOYMENT AND THERMAL ANGIOPLASTY

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to and the benefit of U.S. Provisional Application No. 63/623,851, filed on January 23, 2024, the disclosure of which is incorporated herein by reference in its entirety.

1. Field of the Invention

[0002] The inventive concept relates to a thermal balloon catheter (TBC) device, methods of fabricating the TBC device, and methods of utilizing the TBC device for deploying a biodegradable endovascular medical implant, e.g., biocarpet device, or for performing thermal balloon angioplasty, to treat stenotic vascular disease or vascular disease in general.

2. Background

[0003] More than 230 million adults are affected by lower extremity peripheral artery disease (PAD) worldwide. More than 50% of patients with critical limb ischemia (severe PAD) are treated endovascularly using a stent or balloon angioplasty. Approximately 30-40% of patients treated with stents for lesions in lower extremities experience in-stent restenosis (1SR) within 2 years of implantation. ISR is caused by the imposition of non-homeo static vascular wall stress as a result of stents’ design, material, and structure. ISR patients require a secondary intervention in the form of a secondary angioplasty or bypass surgery as the removal of the failed stent is feasible.

[0004] The introduction of minimally invasive surgical techniques, and the development of various endovascular devices, such as the biocarpet technology, have substantially improved human health care over several decades. Further improvements have been realized by increasing the functionality of these devices and extending the types of procedures where such devices may be employed. It is believed that improvement in the materials of composition and construction of the endovascular devices have provided increased opportunities for optimizing the benefits derived from the devices. For example, utilization of different materials to achieve both improved mechanical properties and biodegradability for medical implant devices. The use of degradable components allows a tissue engineering approach to be pursued where no permanent foreign body is left behind in the patient when there is no longer a need for the implanted medical device. It is known that prior art devices, or pieces of the devices, that remain in the patient can potentially pose a risk of infection, fibrosis, or abrasion. Constructing devices from biodegradable materials substantially reduces or eliminates these risks.

[0005] PAD is difficult to treat, in particular, in vessels placed where flexion is common, specifically, behind the knee, and the prolonging of the disease may result in infection, tissue death and sometimes amputation. The most common form of treatment has been stent placement, in which a stent is inserted to increase blood flow. However, it is difficult to treat these bending and tortuous arteries with these devices and they suffer from restenosis due to complex biomechanical environment. Also, treatment of smaller vessels is challenging because of the size (difficult deployment) and much less room for tissue ingrowth . In addition, the rigid nature of metallic materials, such as stents, have mechanical disadvantages that can prevent it from properly fitting the vessel. Restenosis related to stents is common- especially in complex bending (cross-joint) applications - leading to reintervention. The biocarpet device features and its low profile allows for the treatment of bending and small blood vessels.

[0006] Whereas the biocarpet technology is uniquely suited to address these challenges. The biocarpet technology includes a biodegradable endovascular device that can be thermoformed into a patient’s anatomy in-vivo, allowing maximum flexibility and patient-specific conformability. The biocarpet device is made of a combination of synthetic and bio-polymers and requires a unique proprietary deployment method that uses thermal energy to thermoform and induce structural changes. The clinical target is primarily in the treatment of lower extremity PAD with a particular focus on lesions that span knee joints as bending configurations are the most challenging anatomical locations associated with a high failure rate. The biocarpet may also have applications in the treatment of coronary, aortic, and cerebral vascular disease.

[0007] There is a need in the art for the inventive concept that includes a thermal balloon catheter (TBC) to be utilized in thermal angioplasty or for deployment of a flexible, biodegradable, polymeric, endovascular device, e.g., the biocarpet device. The use of the TBC allows the advancement and/or deployment of extremely thin devices and thereby, significantly reduces the profile of the devices (during advancement and/or deployment). Further, this TBC design allows for the treatment of smaller vascular segments that heretofore were untreatable using standard stent technology. Such treatment is particularly needed in the peripheral vascular beds of the lower leg, to provide effective treatment of PAD across joints.

SUMMARY OF THE INVENTION

[0008] In one aspect, the inventive concept provides a thermal balloon catheter device 12 that includes a catheter tube 1, a balloon 2 connected to the catheter tube 1 and optionally, a biocarpet device 15, wherein the balloon catheter 12 is effective for conducting thermal balloon angioplasty or deployment of the biocarpet device 15, in a target vascular region 14.

[0009] In certain embodiments, the thermal balloon catheter device 12 further includes a pressurization line 3 in communication with the balloon 2; a means 4 for active cooling without interference with pressure; a temperature sensor 5; a pressure sensor 6; and insulating layers 7 on both ends of the balloon 2.

[0010] The thermal balloon catheter 12 that includes the biocarpet device 15, can further include a groove 8 to prevent disorientation during unfurling of the biocarpet devicel5; and a device sheath 13 to prevent dislodgement of the biocarpet device 15 during the advancement to the location of the treatment. The deployment of the biocarpet device 15 can include a thermoformed structure, positioned in the target vascular region, that conforms to geometry or anatomy of the vascular region. The geometry or anatomy can be selected from the group consisting of arteries and veins. In certain embodiments, the biocarpet device 15 includes a metal, metal alloy, polymer or blend thereof selected from the group consisting of collagen, gelatin, tropoelastin, polyesters, polyurethanes, polyurethane ureas and, blends and combinations thereof.

[0011] In certain embodiments, the balloon 2 includes a variety of shapes selected from cylindrical, spherical and/or more complicated shapes, such as, an accordion/bellow shape. [0012] In another aspect, the inventive concept provides a method of performing thermal balloon angioplasty in a target vascular region, including forming a thermal balloon catheter, including a catheter tube; and a balloon; advancing the thermal balloon catheter to a target vascular- region; inflating the balloon into the target vascular region; heating the balloon; then cooling the balloon; and subsequently removing the catheter tube and deflating the balloon. [0013] In another aspect, the inventive concept provides a method of deploying a biocarpet device in a target vascular region, including forming a thermal balloon catheter, including a catheter; and a balloon; forming the biocarpet device; wrapping or rolling the biocarpet device around the balloon in its deflated state; attaching a sheath to the balloon catheter; advancing the thermal balloon catheter to a target vascular region; and deploying the biocarpet device into the target vascular region, including removing the sheath; inflating the balloon to unfurl the biocarpet device; thermoforming the biocarpet device; cooling the biocarpet device; deflating the balloon; forming a thermoformed structure in the target vascular region; and removing the catheter and deflated balloon.

[0014] In this method, the heating step or thermoforming step can include increasing the temperature by a heating technique selected from alternating or direct current resistive heating, light-base heating, radiofrequency heating, and hot fluid circulation. In certain embodiments, the heating technique is performed one or more times with or without a cooling cycle therebetween. In certain embodiments, the thermoformed structure is in a full or partial tube or cylinder shape. The thermoformed structure can conform to the geometry or anatomy of the target vascular region. In certain embodiments, the thermal balloon catheter treats vascular disease. The vascular- disease can be peripheral arterial disease.

[0015] In yet another aspect, the inventive concept provides a multi-stage thermal balloon catheter device 16, including a catheter tube 1; at least two balloons 2 aligned in sequence, connected to the catheter tube 1; and a biocarpet device 15 connected to one of the at least two balloons 2, wherein the multi-stage thermal balloon catheter device 16 is effective for a first balloon 2 configured to conduct thermal balloon angioplasty and a second balloon 2 configured to subsequently deploy the biocarpet device 15, in a target vascular region 14.

[0016] In certain embodiments, the multi-stage thermal balloon catheter device 16 of claim 16, wherein the first and second balloons 2 inflate and deflate independently.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] FIG. 1 is a schematic that illustrates a thermal balloon catheter in accordance with certain embodiments of the inventive concept.

[0018] FIG. 2 is a schematic that illustrates the stages of a biocarpet deployment utilizing the thermal balloon catheter in accordance with certain embodiments of the inventive concept. [0019] FTG. 3 is a schematic that illustrates a multi-stage thermal balloon catheter in accordance with certain embodiments of the inventive concept.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0020] The invention relates to thermal balloon catheters (TBCs), methods for preparation of the TBCs, and their utilization for inserting and deploying biodegradable endovascular’ devices (e.g., biocarpet devices) to target vascular regions, or performing thermal balloon angioplasty. The biocarpet devices are deployed for treating stenotic arterial disease using a rolled and thermoforming method. The devices conform to the patient’s own artery. The devices are fabricated in a manner that their own material stiffness and geometry are optimized to satisfy a targeted vascular wall stress in-vivo. The TBCs are designed and fabricated to safely and efficiently perform balloon angioplasty in a target vascular region of a patient, or deploy the biocarpet device into a target vascular region of a patient. With the safe and efficient operation of the TBC, the balloon angioplasty and biocarpet devices are capable of reducing the risk of restenosis.

[0021] The biocarpet devices are flexible, biodegradable endovascular devices, e.g., composed of a flat, flexible material, which are optionally drug eluting, that provide effective or optimal treatment of peripheral arterial disease, including in small arteries and across joints. The biocarpets utilize one or more, e.g., a blend, of biocompatible polymers and in-situ thermoforming techniques. Due to the unique thermoformability of the biocarpets they are flexible enough and conformable to be inserted into complex vessel geometries. Further, due to their biodegradability, the biocarpet devices are capable of disintegrating once treatment is completed.

[0022] FIG. 1 is a schematic that shows a TBC in accordance with certain embodiments of the inventive concept. FIG. I also illustrates the flow through a TBC. As shown in FIG. 1, the TBC 12 includes a catheter 1, e.g., tube, and a balloon 2 for performing balloon angioplasty or deploying a biocarpet device. The balloon 2 can have a variety of shapes that include but are not limited to cylindrical, spherical, and/or more complicated shapes, such as, an accordion/bellow shape. A pressurization line 3 in communication with the balloon 2 and a fluid line 4 for active cooling without interference with pressure, are positioned through the catheter 1. In certain embodiments, saline/PBS flows through the pressurization and fluid lines 3,4. A temperature sensor 5 and a pressure sensor 6 are positioned in the balloon 2. The temperature sensor 5 includes nichrome wire 9, copper wires 10 and electrical current flowing therethrough. An extra lumen 11 allows blood flow therethrough to potentially be used for active cooling. As shown in FIG. 1, the TBC also includes an insulating layer 7 on both ends of the balloon 2. For use in deploying a biocarpet device, there is a groove 8 to prevent disorientation during unfurling of the biocarpet device. Additionally, the biocarpet device includes a device sheath to prevent dislodgement of the device during the advancement to the location of the treatment.

[0023] The flow through the system is optimized for fluid dynamics.

[0024] For safe and efficient deployment of the biocarpet device, the TBC 12 of the inventive concept is designed to have the following features.

[0025] 1. Blood flows through the extra lumen 11 in the structure of the TBC 12. This feature eliminates/minimizes the time constraint of endovascular scaffold/stent/biocarpet device deployment, as well as angioplasty procedure time. The blood flow through this lumen 11 can also be utilized/optimized for active cooling.

[0026] 2. The temperature sensor 5 is positioned inside of the balloon 2, and is controlled with a single or optionally, a double, feedback loop. A single proportional-integral-derivative (PID) feedback loop allows the user to maintain the surface temperature of the balloon 2 at a constant value. The double PID feedback loop is programmatically added to the system and contributes to (i) increasing the precision of the single PID loop, and (ii) allowing the user to apply a desired temperature-time (current-time) pattern to the balloon 2. Furthermore, this feature is required for the precision and effectiveness of the thermoforming process as well as the temperature control during thermal angioplasty.

[0027] 3. The pressure sensor 6 positioned in the system notifies a clinician that the balloon 2 has reached the vascular wall. The pressure sensor 6 uses the differential pressure of both its sides (one being the applied pressure and the other from the resistance of the vascular wall against balloon pressure). This feature contributes to minimizing the overpressurizing and oversizing of the scaffolds/stents during thermoforming of the biocarpet device or thermal angioplasty.

[0028] 4. The fluid line 4 provides active cooling added to the system via fluid transport (or other conventional methods) to allow for application of the desired temperature-time pattern to the balloon 2 for thermoforming of the biocarpet device or thermal angioplasty. [0029] 5. The inner insulating layer 7 positioned on both ends of the balloon 2 prevents heat transfer to blood during thermoforming of biocarpct device or thermal angioplasty.

[0030] 6. The groove 8 on the balloon 2 allows for the accurate unfurling of the biocarpet device without disorientation. Other methods such as suture-controlled unfurling are suitable for use as alternatives to the groove method.

[0031] In certain embodiments, the biocarpet device includes a flexible, biodegradable polymer form, e.g., sheet, that is wrapped or rolled onto and/or around a deflated balloon 2 of the TBC 12; it is then deployed into a vascular' region of a patient. The in-situ thermoforming process involves the inflation of the underlying balloon 2, and then heating of the inventive device (e.g., flexible polymer sheet). As a result of in-situ thermoforming, the biocarpet device becomes a tube or cylinder article that conforms to the geometry or anatomy of the host artery. Thus, thermoformability allows the biocarpet device to be molded into the shape or geometry of the target vascular region.

[0032] The biocarpet endovascular devices are composed and/or constructed of a flexible, biodegradable material. The material includes synthetic polymers or native biopolymers, or blends thereof. Non-limiting examples of suitable materials for use in the composition and construction of the inventive devices include biocompatible, flexible, biodegradable polymers known in the art, such as, but not limited to, collagen, gelatin, tropoelastin, polyester, polyurethane urea (PUU), polycaprolactone (PCL), poly-L-lactic acid (PLLA), polyglycolic acid (PGA) and, polymer blends and combinations thereof. Further, PUUs possess good biocompatibility with non-toxic degradation products and high elasticity and strength, even in very thin (< 1 mm) formats. PUUs include soft segments such as polycaprolactone, polyethylene glycol, polycarbonate, and the like, diisocyanatebutane and chain extender putrescine.

[0033] Suitable biocarpet endovascular devices for use in the disclosed concept are disclosed in U.S. Patent 18/026,041 filed on March 13, 2023, which is herein incorporated by reference.

[0034] FIGS. 2A-2G are schematics that show the stages of biocarpet device deployment using the catheter as shown in FIG. 1. As shown in FIG. 2A, Stage 1 of deployment, the biocarpet 15 is placed, e.g., wrapped or rolled, on the balloon 2 (e.g., as shown deflated) of the catheter 1. A sheath 13 protects the biocarpet 15 of the catheter 1 from dislodgement in the vascular region 14. In FIG. 2B, Stage 2, the sheath 13 is in a position (e.g., that is pulled back from the catheter 1) such that the biocarpet 15 is not contained in the sheath 13. In FIG. 2C, Stage 3, the balloon 2 is inflated. As a result of inflation, the biocarpet device 15 is unfurled. In FIG. 2D, Stage 4, the biocarpct 15 is thcrmoformcd. In FIG. 2E, Stage 5, the catheter 1 is cooled down. In FIG. 2F, Stage 6, the balloon 2 is deflated, and in FIG. 2G, Stage 7, the balloon 2 is taken out leaving the biocarpet 15 in place in the vascular region 14.

[0035] 7. As shown in FIG. 2A, the sheath 13 is positioned on the catheter 1 as a separate component that protects the biocarpet 15 from dislodgement during advancement to the location of treatment. This sheath 13 can be in the form of a full tube, arms, sutures, and other designs. [0036] 8. An alternative method for the prevention of biocarpet 15 disorientation, as well as insulation of blood from heat, is using two isolating balloons on both ends of the main balloon 2. [0037] In certain embodiments, wherein the TBC is utilized for thermal angioplasty, each of the features 6, 7 and 8 as described above are optional, i.e., not required features of the TBC.

[0038] FIG. 3 is a schematic that shows a multi-stage TBC in accordance with certain embodiments of the inventive concept. FIG. 3 also illustrates the flow through a multi-stage TBC. As shown in FIG. 3, the multi-stage TBC 16 includes a catheter 1, e.g., tube, and balloons 2; a second balloon 2 on a proximate side (e.g., left side in FIG. 3) of catheter 1 and a first balloon 2 on a distal side (e.g., right side in FIG. 3) of catheter 1, for deploying a biocarpet 15 and performing balloon angioplasty, respectively. Each of the balloons 2 can have a variety of shapes that include but are not limited to cylindrical, spherical, and/or more complicated shapes, such as, an accordion/bellow shape. A pressurization line 3 in communication with the second balloon 2 is positioned through a portion of the catheter 1 (on the proximate side of catheter 1, e.g., left side in FIG. 3) and a fluid line 4 is also positioned through a portion of catheter 1 (on the proximate side of catheter 1, e.g., left side of FIG. 3), for active cooling without interference with pressure. In certain embodiments, saline/PBS flows through the pressurization and fluid lines 3,4. A temperature sensor 5 and a pressure sensor 6 are positioned in the second balloon 2. The temperature sensor 5 includes nichrome wire 9, copper wires 10 and electrical current flowing therethrough. An extra lumen 11 positioned through the length of the catheter 1 allows blood flow therethrough to potentially be used for active cooling. As shown in FIG. 3, the TBC 16 also includes an insulating layer 7 on both ends of the balloons 2. For use in deploying the biocarpet 15, there is a groove 8 in the second balloon 2 to prevent disorientation during unfurling of the biocarpet 15. [0039] Additionally, the biocarpet device includes a device sheath to prevent dislodgement of the device during the advancement to the location of the treatment (as shown in FIGS. 2A-2G). [0040] The flow through the system is optimized for fluid dynamics.

[0041] For safe and efficient deployment of the biocarpet 15, the second balloon 2 of TBC 16 of the inventive concept is designed to have the following features.

[0042] 1. Blood flows through the extra lumen 11 in the structure of the TBC 16. This feature eliminates/minimizes the time constraint of endovascular scaffold/stent/biocarpet device deployment, as well as angioplasty procedure time. The blood flow through this lumen 11 can also be utilized/optimized for active cooling.

[0043] 2. The temperature sensor 5 is positioned inside of the second balloon 2, and is controlled with a single or optionally, a double, feedback loop. A single proportional-integral- derivative (PID) feedback loop allows the user to maintain the surface temperature of the second balloon 2 at a constant value. The double PID feedback loop is programmatically added to the system and contributes to (i) increasing the precision of the single PID loop, and (ii) allowing the user to apply a desired temperature-time (current-time) pattern to the second balloon 2. Furthermore, this feature is required for the precision and effectiveness of the thermoforming process as well as the temperature control during thermal angioplasty.

[0044] 3. The pressure sensor 6 positioned in the system notifies a clinician that the second balloon 2 has reached the vascular wall. The pressure sensor 6 uses the differential pressure of both its sides (one being the applied pressure and the other from the resistance of the vascular wall against balloon pressure). This feature contributes to minimizing the overpressurizing and oversizing of the scaffolds/stents during thermoforming of the biocarpet device or thermal angioplasty.

[0045] 4. The fluid line 4 provides active cooling added to the system via fluid transport (or other conventional methods) to allow for application of the desired temperature-time pattern to the second balloon 2 for thermoforming of the biocarpet device or thermal angioplasty.

[0046] 5. The inner insulating layer 7 positioned on both ends of the second and first balloons 2 prevents heat transfer to blood during thermoforming of biocarpet device or thermal angioplasty. [0047] 6. The groove 8 on the second balloon 2 allows for the accurate unfurling of the biocarpct device without disorientation. Other methods such as suturc-controllcd unfurling arc suitable for use as alternatives to the groove method.

[0048] In certain embodiments, the biocarpet 15 includes a flexible, biodegradable polymer form, e.g., sheet, that is wrapped or rolled onto and/or around a deflated second balloon 2 of the TBC 16; it is then deployed into a vascular region of a patient. The in-situ thermoforming process involves the inflation of the underlying second balloon 2, and then heating of the inventive device (e.g., flexible polymer sheet). As a result of in-situ thermoforming, the biocarpet 15 becomes a tube or cylinder article that conforms to the geometry or anatomy of the host artery. Thus, thermoformability allows the biocarpet 15 to be molded into the shape or geometry of the target vascular region 14.

[0049] The biocarpet endovascular device is composed and/or constructed of a flexible, biodegradable material. The material includes synthetic polymers or native biopolymers, or blends thereof. Non-limiting examples of suitable materials for use in the composition and construction of the inventive devices include biocompatible, flexible, biodegradable polymers known in the art, such as, but not limited to, collagen, gelatin, tropoelastin, polyester, polyurethane urea (PUU), polycaprolactone (PCL), poly-L-lactic acid (PLLA), polyglycolic acid (PGA) and, polymer blends and combinations thereof. Further, PUUs possess good biocompatibility with non-toxic degradation products and high elasticity and strength, even in very thin (< 1 mm) formats. PUUs include soft segments such as polycaprolactone, polyethylene glycol, polycarbonate, and the like, diisocyanatebutane and chain extender putrescine.

[0050] As shown in FIGS. 2A-2G, the stages of biocarpet device deployment for the second balloon 2 of the catheter 1 shown in FIG. 3 include, as shown in FIG. 2A, Stage 1 of deployment, the biocarpet 15 is placed, e.g., wrapped or rolled, on the second balloon 2 (e.g., as shown deflated). A sheath 13 protects the biocarpet 15 from dislodgement in the vascular region 14. In FIG. 2B, Stage 2, the sheath 13 is in a position such that the biocarpet 15 is not contained in the sheath 13. In FIG. 2C, Stage 3, the second balloon 2 is inflated. As a result of inflation, the biocarpet 15 is unfurled. In FIG. 2D, Stage 4, the biocarpet 15 is thermoformed. In FIG. 2E, Stage 5, the catheter 1 is cooled down. In FIG. 2F, Stage 6, the second balloon 2 is deflated, and in FIG. 2G, Stage 7, the second balloon 2 is taken out leaving the biocarpet 15 in place in the vascular region 14. [0051] 7. As shown in FIG. 2A, the sheath 13 is positioned on the catheter 1 as a separate component that protects the biocarpct 15 from dislodgcmcnt during advancement to the location of treatment. This sheath 13 can be in the form of a full tube, arms, sutures, and other designs. [0052] As shown in FIG. 3, the distal side (i.e., right side of FIG. 3) of the catheter 1 that includes the first balloon 2 is utilized for thermal angioplasty and thus, each of the features 6, 7 and 8 as described above are optional, i.e., not required features of the distal side catheter 1.

[0053] Biocarpet deployment for the multi-stage TBC 16 as shown in FIG. 3, includes inserting and positioning the multi-stage TBC 16 at the location of a target vascular region, e.g., artery, of a patient. The first balloon 2 on the distal side (i.e., right side of FIG. 3) of the catheter 1 functions as a thermal angioplasty balloon to open the artery. The first balloon 2 is deflated and moved forward through the artery such that the second balloon 2 on the proximate side of the catheter 1 (i.e., left side of FIG. 3) is then further advanced, e.g., to a location of disease or plaque within the artery. The second balloon 2, which includes the biocarpet 15, is inflated to deliver and thermoform the biocarpet 15 (as shown in FIGS. 2A-2G). The second balloon 2 is then deflated and removed from the artery. Thus, in this embodiment, for the multi-stage TBC 16, the first balloon 2 functions to perform the angioplasty and the second balloon 2 subsequently (e.g., sequentially) functions to perform the biocarpet deployment.

[0054] With respect to the multi-phase TBC, the inflation and deflation of the two balloons are independent.

[0055] In certain embodiments, the biocarpet devices contain, e.g., are composed of, a flexible, biodegradable material such as synthetic polymers or native biopolymers, or blends thereof. Non-limiting examples of suitable materials include biocompatible, flexible, biodegradable polymers known in the art, such as, but not limited to, collagen, gelatin, tropoelastin, polyester, polyurethane urea (PUU), polycaprolactone (PCL), poly-L-lactic acid (PLLA), poly glycolic acid (PGA) and, polymer blends and combinations thereof, as well as metals and metal alloys. PUUs include soft segments such as polycaprolactone, polyethylene glycol, polycarbonate, and the like, diisocyanatebutane and chain extender putrescine. In certain embodiments, the polymers or polymer blends include recombinant human tropoelastin to form a highly deformable polymer or polymer blend for construction of the inventive device. The degradation profiles and mechanical properties of the polymers or polymer blends are tailored or pre-selected by changing or varying the molecular weight and the composition of the soft segments. In certain embodiments, the endovascular devices according to the invention arc fully (i.c., 100%) degradable.

[0056] A thermoplastic elastomer is easily processed into various different shapes and forms; the resulting polymeric material is in a flexible form, such that it is conformable to various complex, arterial geometries such as small arteries and veins. In certain embodiments, the polymeric material is in a flat, flexible form, such as a flat, flexible sheet, cover, membrane, matrix or coating composed of, or containing, one or more of the aforementioned synthetic and native biopolymers.

[0057] Suitable materials of composition for the balloon(s) include but are not limited to silicone and polyester (PET), and nylon.

[0058] In accordance with certain embodiments of the inventive concept, the flexible biocarpet device is wrapped or rolled onto and/or around the outside surface of the balloon of the of the TBC to surround or encompass the balloon in its deflated state (such that the deflated balloon is positioned within an open/interior space formed by the wrapped or rolled biocarpet device), and the TBC with biocarpet device is advanced/deployed to the target vascular region of treatment. In certain embodiments, the target vascular region is a complex vascular lesion anatomy such as a diseased peripheral vascular segment or host artery. Before and during advancement, a sheath is employed to at least partially cover and/or protect the biocarpet device from (pre-mature) dislodgement. Once advanced to the target region or location, the sheath is pulled back (e.g., by a clinician), and the biocarpet device is unfurled as a result of balloon pressurization, e.g., inflation. The biocarpet device is then thermoformed (e.g., by electrical current) to attach the adjacent layers using a desired temperature-time pattern. Thermoforming includes various methods and techniques such as, but not limited to, resistive heating, light-base heating, radiofrequency heating, and hot fluid circulation. Following heating, the balloon is cooled and then deflated. Typically, the heat is applied for a period of seconds. In certain embodiments, the heating step is repeated one or more times. In certain embodiments, a cooling cycle is implemented between each of the subsequent heating steps. The period of time for heating and the number of heating steps varies. The heating is conducted such that the wrapped or rolled biocarpet device is transformed, re-configured, or molded. During and following the thermoforming process, the biocarpet device, e.g., flat, flexible sheet, is formed into a thermoformed structure or article, e.g., a tube or cylinder, that conforms to the geometry or anatomy of the target vascular region. The biocarpet device is cooled to lock the device in place. The balloon is then deflated and the entire TBC is removed, while the biocarpct device (transformed, re-configured, or molded) remains in place.

[0059] The thermoforming process conducted at the target vascular region, transforms the flat, flexible polymer sheet of the biocarpet device into a thermoformed structure, e.g., tube or cylinder. The low profile and thermoformability of the biocarpet device allows it to be advanced and deployed into smaller diameter peripheral vessels using the safe and efficient TBC, thus allowing the treatment of peripheral vascular disease that is not achievable with purely metallic devices, e.g., stents.

[0060] One or more benefits of the TBC for performing thermal balloon angioplasty or deploying a biocarpet device, as compared to traditional or known catheters, includes but are not limited to the following:

(i) Continuous blood flow during deployment;

(ii) Pressure control during deployment;

(iii) Temperature control during thermoforming;

(iv) No heat transfer to blood during thermoforming;

(v) No biocarpet device dislodgement during advancement; and

(vi) No biocarpet device disorientation during deployment.

[0061] The conventional approach for treatment of peripheral arterial disease involves metallic stents, which include a cylinder that is fabricated at a specific (larger) diameter and then compressed to fit around a (much smaller) balloon catheter. This approach limits the size of arteries that can be treated using stents, and also results in non-homeostatic vascular wall stresses in the artery immediately proximal and distal to the lesion, which is known to induce stent restenosis. These issues are drastically exacerbated when treating vascular lesions occurring within complex vascular anatomy and in vessels that span bending joints, as commonly occurs in the knee (e.g., increased stress in the vessel wall during and after deploying a standard metallic in a straight leg configuration). Whereas, the inventive TBC safety and efficiently performs thermal balloon angioplasty in a target vascular region, or advances and deploys to a target vascular region the biocarpet device that is composed of a flexible, biodegradable polymer form, e.g., sheet, wrapped or rolled onto and/or around a deflated balloon catheter, and subsequently thermoformed in situ to conform to the geometry or anatomy of the target vascular anatomy. [0062] The biocarpet device deployed by the TBC is fully biodegradable and therefore, allows the delivery of significantly larger amounts of anti-rcstcnotic and/or antithrombotic drug as the device degrades into the patient body over a period of time. As an added benefit, this increased delivery volume allows for more efficient and improved approaches in controlled temporal delivery of the drug. For example, the ability to include and elute both acute and chronic therapeutic drugs within the same device. The various mechanisms known in the art for eluting drugs from a polymeric implant device are applicable to the inventive device. These methods include, but are not limited to, attaching a drug directly or indirectly to the polymeric material surface of the device, and encapsulating or embedding a drug into the polymeric material, e.g., matrix. The attaching and encapsulating or embedding of the drug to or into the polymer material is performed either during or subsequent to preparation of the polymer. In certain embodiments, the polymeric material contains a multiple or a plurality of pores, intentionally, for storage of a drug to be eluted from the device. The drug eluting mechanism of the inventive device incudes the controlled and sustained release of various pharmaceutical agents, which are known in the art.

[0063] Whereas particular embodiments of the invention have been described herein for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details may be made without departing from the invention as set forth in the appended claims.

Claims

We claim:

1. A thermal balloon catheter device 12, comprising: a catheter tube 1 ; a balloon 2 connected to the catheter tube 1 ; and optionally, a biocarpet device 15, wherein the balloon catheter 12 is effective for conducting thermal balloon angioplasty or deployment of the biocarpet device 15, in a target vascular region 14.

2. The thermal balloon catheter device 12 of claim 1, further comprising: a pressurization line 3 in communication with the balloon 2; a means 4 for active cooling without interference with pressure; a temperature sensor 5 ; a pressure sensor 6; and insulating layers 7 on both ends of the balloon 2.

3. The thermal balloon catheter 12 of claim 1, including the biocarpet device 15, further comprising: a groove 8 to prevent disorientation during unfurling of the biocarpet device 15; and a device sheath 13 to prevent dislodgement of the biocarpet device 15 during the advancement to the location of the treatment.

4. The thermal balloon catheter 12 of claim 1, comprising the biocarpet device 15, wherein deployment of the biocarpet device 15 includes a thermoformed structure, positioned in the target vascular region, that conforms to geometry or anatomy of the vascular region.

5. The thermal balloon catheter 12 of claim 4, wherein the geometry or anatomy is selected from the group consisting of arteries and veins.

6. The thermal balloon catheter 12 of claim 1 , comprising the biocarpet device 15, wherein the biocarpct device 15 comprises a metal, metal alloy, polymer or blend thereof selected from the group consisting of collagen, gelatin, tropoelastin, polyesters, polyurethanes, polyurethane ureas and, blends and combinations thereof.

7. The thermal balloon catheter 12 of claim 1, wherein the balloon 2 comprises a variety of shapes selected from cylindrical, spherical and/or more complicated shapes, such as, an accordion/bellow shape.

8. A method of performing thermal balloon angioplasty in a target vascular region, comprising: forming a thermal balloon catheter, comprising: a catheter tube; and a balloon; advancing the thermal balloon catheter to a target vascular region; inflating the balloon into the target vascular region; heating the balloon; then cooling the balloon; and subsequently removing the catheter tube and deflating the balloon.

9. A method of deploying a biocarpet device in a target vascular region, comprising: forming a thermal balloon catheter, comprising: a catheter; and a balloon; forming the biocarpet device; wrapping or rolling the biocarpet device around the balloon in its deflated state; attaching a sheath to the balloon catheter; advancing the thermal balloon catheter to a target vascular region; and deploying the biocarpet device into the target vascular region, comprising: removing the sheath; inflating the balloon to unfurl the biocarpet device; thermoforming the biocarpet device; cooling the biocarpet device; deflating the balloon; forming a thermoformed structure in the target vascular region; and removing the catheter and deflated balloon.

10. The method of claim 8 or 9, wherein the heating step or thermoforming step comprises increasing the temperature by a heating technique selected from alternating or direct current resistive heating, light-base heating, radiofrequency heating, and hot fluid circulation.

11. The method of claim 10, wherein the heating technique is performed one or more times with or without a cooling cycle therebetween.

12. The method of claim 9, wherein the thermoformed structure is in a full or partial tube or cylinder shape.

13. The method of claim 9, wherein the thermoformed structure conforms to the geometry or anatomy of the target vascular region.

14. The method of claim 9, wherein the thermal balloon catheter treats vascular disease.

15. The method of claim 14, wherein the vascular disease is peripheral arterial disease.

16. A multi-stage thermal balloon catheter device 16, comprising: a catheter tube 1 ; at least two balloons 2 aligned in sequence, connected to the catheter tube 1 ; and a biocarpet device 15 connected to one of the at least two balloons 2, wherein the multi-stage thermal balloon catheter device 16 is effective for a first balloon 2 configured to conduct thermal balloon angioplasty and a second balloon 2 configured to subsequently deploy the biocarpet device 15, in a target vascular region 14.

17. The multi-stage thermal balloon catheter device 16 of claim 16, wherein the first and second balloons 2 inflate and deflate independently.