WO2017054015A2

WO2017054015A2 - Methods or devices for intra-bronchial delivery of lung hyperinflation treatment

Info

Publication number: WO2017054015A2
Application number: PCT/US2016/059719
Authority: WO
Inventors: George Bourne; Benjamin David BELL; Jianmin Li
Original assignee: Soffio Medical Inc.
Priority date: 2015-09-25
Filing date: 2016-10-31
Publication date: 2017-03-30
Also published as: WO2017054015A3

Abstract

Methods and devices to improve lung function in a patient having restricted ventilation from chest hyperinflation and related pulmonary conditions. A bronchoscopically delivered implantable airway bypass device may relieve trapped air. The minimally invasive methods may include procedures that reduce the time required by the overall healing process.

Description

METHODS OR DEVICES FOR INTRA-BRONCHIAL DELIVERY OF LUNG

HYPERINFLATION TREATMENT

RELATED APPLICATIONS

[0001] This application relates to and has the benefit of U.S. provisional application 62/233, 122 filed September 25, 2015 and 62/249,036 filed October 30, 2015, the entirety of each of these applications are incorporated by reference.

TECHNICAL FIELD

[0002] This invention relates to implantable medical devices and methods for improving chest mechanics and pulmonary function.

BACKGROUND OF THE INVENTION

[0003] The present invention generally relates to implantable medical devices and methods for improving chest mechanics and pulmonary function. In preferred embodiments, the present invention relates to apparatuses and methods for minimally invasive delivery for providing alternate air passages for reducing lung volume by fluidly connecting isolated segments of lung tissue with functional portions of the bronchial system. Specifically, the delivery of the devices through the patient airway with the use of bronchoscopes is discussed in further detail herein.

[0004] Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease that causes difficult breathing as a result of obstructed airflow from the lungs. COPD is a chronic medical condition that progresses over time and affects over 30 million people, or roughly 10% of the U.S. population. Specific pulmonary diseases include asthmatic bronchitis, chronic bronchitis and emphysema. While numerous devices and methods have been proposed or are used to deliver wide- ranging therapies, none has proven to be entirely effective.

[0005] In particular, one obstructive lung disease, known as diffuse lung emphysema, is particularly difficult to treat and currently has few treatment options. Patients with emphysema are unable to exhale appropriately, which leads to lung hyperinflation, trapping air in at least a portion of the lungs. The debilitating effects of the hyperinflation are extreme respiratory effort, the inability to conduct gas exchanges in satisfactory proportions, severe limitations of exercise ability, feelings of dyspnea and associated anxiety. Although optimal pharmacological and/or other medical therapies may work well in the earlier stages of the disease, as it progresses, these therapies become increasingly less effective. For patients that have reached this stage in the disease progression, the standard of care is often surgical treatment involving invasive lung volume reduction surgery, lung transplantation or both.

[0006] It is generally accepted by clinicians that respiratory impairment in emphysema has an important 'mechanical' component. Destruction of pulmonary parenchyma causes compounding disadvantages of a decreased mass of functional lung tissue decreasing the amount of gas exchange, and a loss in elastic recoil resulting the inability to equally or substantially completely exhale the amount of air that was inhaled on the previous breath. This leads to hyper-expansion of the chest with a flattened diaphragm, widened intercostal spaces, and horizontal ribs, all resulting in increase in difficulty breathing. When the destruction and hyper- expansion occur in a non-uniform manner, the diseased lung tissue can expand to crowd the relatively less diseased or normal lung tissue, further reducing lung function by preventing optimal ventilation of the less diseased or normal lung. As such, lung volume reduction surgery (LVRS) involving the surgical removal of the most affected lung regions conceptually would allow the relatively spared part of the remaining lung to function in mechanically improved conditions.

[0007] As a result of the non-uniform nature of parenchymal destruction typically associated with the disease, addressing only the portion of the lung most effected by the disease, while letting the remaining lung to function normally (e.g., expand in a satisfactory manner, and improve the overall elastic recoil of the chest cavity) is not only considered relatively feasible, but may be favored as an alternative to drug therapies that affect both healthy and diseased lung parenchyma. However, many surgical solutions involving the use of implantable devices have shown difficulties with long term device performance. These difficulties may include device displacement, tissue ingrowth, occlusion by naturally occurring secretions such as mucus or other secretions resulting from the heightened pro-inflammatory state in COPD, excessive bleeding, or rejection of an implant by the body. Thus, improvements and alternative to currently known therapies have long been sought after.

BRIEF SUMMARY OF THE INVENTION

[0008] The present invention provides methods, systems, and devices for facilitating lung volume reduction in patients suffering from a hyper-inflated lung, resulting from a chronic obstructive pulmonary disease or other conditions. Because the systems and devices are delivered through the airways through the mouth or nose (endotracheally), they are generally dimensioned to be minimally invasive. The methods described can result in quicker recovery times and less discomfort than experienced with conventional surgery and procedures. The systems and devices provide means and methods for creating alternate air passages that fluidly connect isolated segments of lung tissue with the healthy bronchial system, thereby freeing the trapped air that causes lung hyper-inflation.

[0009] In one embodiment of the present invention, an airway bypass device delivery system is provided for delivering the device in a collapsed state to a target lung location or passageway. In preferred embodiments, the delivery system includes an endoscope, or visualization instrument (bronchoscope) specifically configured for endobronchial advancement into the lung, leading to the target lung passageway. In some embodiments, the endoscope is configured for visualization purposes and can be modified for use as described. It may be appreciated that any suitable device for endoscopy may be used, including conventional bronchoscopes, specifically configured for use in the lungs. A principal advantage of the present invention is that it allows a user to modify a conventional endoscope for bronchoscopic use in delivery of an airway bypass device delivery system in a convenient and economical manner.

[0010] The scope or instrument comprises a proximal end, a distal end, and working lumen extending therethrough, in addition to means for visualization near the distal end. The system includes the scope and a delivery catheter having a proximal end, a distal end and a receptacle formable within its distal end for loading the collapsed airway bypass device therein. The delivery catheter is dimensioned to be able to slide through the working lumen of the scope, such that its distal end of the catheter may be advanced beyond the distal end of the scope. In some cases, the delivery catheter comprises a delivery sheath located at the distal end. It is envisioned that the delivery sheath may facilitate the entry of the device into parenchymal tissue or prevent the premature deployment of the device.

[0011] The endoscope configured for device delivery may further comprise a housing, configured to remain external during device delivery. Additionally, the delivery catheter may further comprise a handle and be configured to be advanced or interlock with the endoscope to stabilize the system during delivery. The collapsible airway bypass device may be deployed manually by advancing the delivery catheter or by manipulation of the handle of the delivery catheter. In a further embodiment, it is envisioned that the device may be deployed automatically after receiving input from a user or practitioner.

[0012] When passage through lung parenchyma is needed, the delivery catheter may be configured with additional delivery mechanisms. These mechanisms may include a slidably extendable mechanism to safely facilitate penetration such as a trochar, coring element, guide wire, or other means for safely perforating the tissue at the distal end of the catheter. The distal end of the delivery catheter may be retractable to reveal the device within the target passageway. Sufficient retraction of the delivery catheter may also expose delivery sheath. Typically, the distal end of the delivery catheter has portions of variable flexibility to allow the catheter to be smoothly advanced through a working lumen with or without a guide wire, or any shape or curvature without applying forces sufficient to redirect or dislodge the endoscope in use.

[0013] In preferred embodiments, the delivery system further includes a self- centering clamp to grip and center the collapsed airway bypass device for delivery. Alternatively, it may be appreciated that the delivery, clamp and centering devices many have a variety of suitable shapes and forms.

[0014] In some embodiments, the collapsible airway bypass device has a self- expanding design and is contained in the delivery sheath. Once the delivery catheter is placed, the device is subsequently advanced beyond the delivery sheath. Because of the self-expanding design, exposure of the collapsible airway bypass device may be used to deploy the device once it is appropriately positioned in a passageway. In some embodiments, the collapsible airway bypass device may expand in free space to a fully deployed diameter of less than 5mm upon deployment. In a further embodiment, the fully deployed diameter may also range between approximately lmm-5mm, 5mm-30mm or 30-50mm. The structure of the collapsible airway bypass device comprises an air intake component surrounded by a scaffold structure configured to surround the component within the lung. Alternatively, in some embodiments, the scaffolding may also be known as the expandable structure and may comprise a scaffolding, a cage, a basket, a mesh, a weave, or a stent that can be delivered in a smaller, undeployed state and expanded to a larger deployed state having an increased diameter and volume.

[0015] The expandable structure may comprise of a single wire, wire network, polymer, or any other type of framework. In one preferred embodiment the expandable structure is comprised of a nickel and titanium metal alloy wire structure, nitinol. The wire structure is used to illustrate examples in the following descriptions, but it can be appreciated that the framework can be of a variety of types. The expansion of the device, including the structure and air intake pathway, may be deliberately retarded to reduce harm or trauma to lung tissue. Alternatively, the collapsible airway bypass device may also be expanded by alternative mechanisms after it has been released into the lung passageway.

[0016] It may also be appreciated that the delivery system and/or loading system may be used for a variety of applications. For example, components of the delivery system may be used to deliver fistula plugs, stents, or drugs and/or devices for the treatment of other bronchopulmonary conditions. Further, components of the system may be modified for delivery, removal, injection, tissue collection, inspection, or other treatments.

[0017] Other advantages of the present invention are described and will become apparent from the description to follow, in consideration with the accompanying drawings.

SUMMARY OF THE DRAWINGS

[0018] FIGURE 1 is an anatomical view of the human thorax with chest structures including a lung and a partial outline of the bronchial system.

[0019] FIGURE 2A is a close-up view of the bronchial system of Figure 1 with a detailed illustration of the airway.

[0020] FIGURE IB is a further close-up view of the bronchial system of Figure 1 with a detailed illustration and partial cross section of lung alveoli.

[0021] FIGURE 3, and the detailed views of 3A-C are external views of the human lung with detailed views of lung alveoli of deteriorating health.

[0022] FIGURE 4 A is the anatomical view of Figure 1 including a lung and a partial outline of the bronchial system, with a cut-out of the lung showing a dead space, or bulla within the lung.

[0023] FIGURE 4B is a close-up view of the bronchial system of Figure 4A showing the dead space, or bulla, exhibiting collateral ventilation, but not in fluid communication with the bronchial system. [0024] FIGURE 4C is a close-up view of the bronchial system of Figure 4B showing the dead space, or bulla, exhibiting collateral ventilation, now in in fluid communication with the bronchial system through an airway bypass device.

[0025] FIGURE 5 A is an illustration showing the similar mechanism by which an airway bypass device and healthy lung alveoli function to allow full exhalation.

[0026] FIGURE 5B is a close-up view of the bronchial system showing a deployed airway bypass device in detail. The device in Figure 5B further comprises an optional air intake component. It is appreciated that embodiments shown with an air intake component are also envisioned with the component replaced with a fluid passage.

[0027] FIGURE 6A is a side-by-side comparison showing the expandable structure of the airway bypass device. The device on the left is configured with air intake ports, while the device on the right is only the expandable structure with the port structure removed.

[0028] FIGURE 6B shows an alternative expandable structure of the airway bypass device with two cage structures connected by a relatively narrow-diameter stem.

[0029] FIGURE 7 is a schematic view of the expandable structure of the airway bypass device, shown formed by a single weave that begins and terminates with in membrane structure.

[0030] FIGURE 8A is a view of the bronchial system showing one potential delivery location for an airway bypass device in relation to a endoscopic delivery device.

[0031] FIGURE 8B is a view of the bronchial system showing a deployed airway bypass device in relation to a proximal delivery device.

[0032] FIGURE 9 is a simplified schematic view showing a catheter with handle or housing providing endotracheal access to the pulmonary system of a patient.

[0033] FIGURE 10 is a simplified schematic view showing the distal end of a catheter configured with a visualization element and a lumen through which a delivery catheter with the airway bypass device is passed to perform a delivery to the pulmonary system of a patient. [0034] FIGURE 11A is an illustration of the delivery device with handle. The expandable structure is shown below the delivery device.

[0035] FIGURE 11B is an illustration of the delivery catheter device with the handle, slideably advanced and in operation.

[0036] FIGURE 11C is an illustration of the distal tip of the delivery catheter showing a sheath covering the collapsed airway bypass device, which has been loaded into the delivery catheter.

[0037] FIGURE 12A-E are simplified schematic views showing the distal end of delivery catheter during device delivery. Figs. 12A-C show the device partially and reversibly deployed, not having reached a fully expanded form. Figure 12D and 12E show the device substantially and reversibly deployed and forming the fully deployed shape. Figure 12E also shows the delivery catheter being withdrawn away from the device after deployment.

DETAILED DESCRIPTION OF THE DRAWINGS

[0038] Systems, methods and devices are described herein for improving the mechanics of a diseased lung of a patient by implanting an airway bypass device 150 that relieves pressure within the lung. The method and device may comprise an implantable device, that may be delivered intra-bronchially via a minimally invasive bronchoscope procedure, and may be configured to minimize tissue regrowth that interferes with device performance, to minimize device rejection, to create a cavity in lung parenchyma, to transport fluid (e.g. air) trapped in a first position within the cavity to a second position within the bronchial system, and to allow air to be expelled upon exhalation.

[0039] Figure 1 is a schematic illustration of the thoracic cavity, which contains structures of the respiratory system including a diaphragm 104, trachea 109, bronchi 110 and lungs 100. An inhalation is typically accomplished when the muscular diaphragm 104, at the floor of the thoracic cavity, contracts and flattens, while contraction of intercostal muscles 102 lift the rib cage up and out. These actions produce an increase in volume, and a resulting partial vacuum, or negative pressure, in the thoracic cavity, resulting in atmospheric pressure pushing air into the lungs, inflating them. In a healthy person, an exhalation results when the diaphragm 104 and intercostal muscles 102 relax, and elastic recoil of the rib cage and lungs 100 expels the air. In a patient having a disease such as COPD, emphysema, or chronic bronchitis, a restriction in air pathways may cause resistance to air flow and impede the ability of air to be expelled, in at least a portion of the lungs, upon muscle relaxation and elastic recoil of the rib cage. The inability to expel air from the restricted portion of the lung may result in a need for increased physical exertion to expel the air, increased residual volume, barrel chest syndrome, or feelings of dyspnea and anxiety. Lung parenchyma 106 is the tissue of the lung 100 involved in gas transfer from air to blood and includes alveoli, alveolar ducts and respiratory bronchioles.

[0040] In a close-up of the lung 100, showing the distal bronchioles 212, alveolar ducts 214 and alveoli 216, Figure 2A and 2B provide illustrations of the microscopic structure of the lung 100. It is at these smaller airway 110 structures that the effects of pulmonary emphysema are the most apparent. Figure 3 compares alveoli 216 of progressively (See Figures 3A-C) worsening condition. Healthy alveoli 216 are distinctly spherical and elastic, while diseased structures can become swollen, fused or entirely blocked off. COPD is characterized by slow or inefficient flow of gas (e.g., air) and fluid communication 220 that is required for the exiting and emptying alveoli 216. Pulmonary emphysema, is defined as "an abnormal permanent enlargement of the air space distal to the terminal bronchioles, accompanied by destruction of the alveolar walls, and without obvious fibrosis." In pulmonary emphysema, air becomes trapped in a lung 100 and the lung may become characterized by the fusion of alveolar walls or loss of elasticity in lung tissue 106. The phenomenon of air trapping begins when a breath is initiated before the exhalation of substantially all of the air inhaled on the previous breath is completed. Over time, an abnormally high amount of air is withheld in the lungs 100, for example in the alveoli 216 and alveolar ducts 214 and bronchioles 212. Diseased parenchyma is unable to communicate the trapped air to the bronchial system. As emphysema progresses, the alveoli and alveoli ducts collapse or fuse together and the air filled cavities of the lung 100 become "dead space" 222 that further exacerbates poor airflow and decreased expiration. Figure 4A provides a representation of that dead space 222 in a cut-away, formed in parts of the lung parenchyma 106. Establishment and maintenance of fluid communication 220 enables the device 150 to empty the entire lobe or entire lung 110 through one or more artificial channels.

[0041] One envisioned method of creating fluid communication 220 may comprise creating a small space in a lung 110 that capable of affecting a much larger volume of the lung through a natural phenomenon called collateral ventilation, wherein air in the larger volume can flow to the created space. The exact mechanism of collateral ventilation is somewhat unclear and often debated, but the collateral ventilation pathways 218 connects dead space 222 to allow gas to pass freely from space 222 to space within the parenchyma. While gas may be moved through the lung, the diseased airways may still prevent its escape to the atmosphere during exhalation.

[0042] Specifically, Figure 4B illustrates that trapped air may be able move through the dead space 222, or bulla, but are unable to exit the lung 100 through exhalation. Candidate air pathways for collateral ventilation include the interalveolar pores of Kohn, the bronchial-alveolar communications of Lambert, and the interbronchiolar pathways of Martin. Deployment and use of an airway bypass device 150 may allow air to escape from the relatively small space created in the lung and thus relieve air trapped in the larger volume of lung that is connected to the space by collateral ventilation. Figure 4C is an illustration that shows the use of collateral ventilation pathways 218 functioning to drain the whole lobe of a lung 100 through the fluid connection formed by the device 150. As such, devices and methods are disclosed for relieving hyperinflation of the lung having restricted airflow, for example due to COPD, emphysema or chronic bronchitis, and relieving symptoms of dyspnea and anxiety and improving quality of life.

[0043] A device and method of treatment, such as the one shown in Figure 5 A and 5B, have been conceived that allow auxiliary ventilation of a lung (e.g. enhanced, more complete or faster exhalation, pressure relief, reduction of residual volume) from small air-filled spaces where air is trapped. Figure 5B shows a device (size exaggerated) performing functions equivalent to healthy alveoli 216. A device and method may allow air to pass from a first position within the lung to a second position. The first position may be an area of the lung that has higher pressure relative to atmosphere at the end of a natural expiration period of the breath. The second position may be within the bronchial or airway 110 system to allow for exhalation into the atmosphere. Alternatively, the second position may be within the natural airways 110 of the patient's pulmonary system that has an air pathway to atmosphere that is less restricted, for example a location within the lung 100 or bronchus.

[0044] The device may further comprise an air intake component 165 and may be placed by anatomical position. Additionally, access and delivery via bronchoscopy provides a minimally invasive means for deployment that is envisioned in at least some embodiments. For example, the device 150 may be placed in an upper (e.g. superior anatomical position) portion of a patient's lung, such as an upper lobe of a lung 100. Location may be chosen for placement of the device 150 (including the distal portion of the device) based on factors such as low tissue density, low blood flow, trapped air, presence of a "dead-space" bulla 222, or depth. The proximal portion 163 of the device comprises an air escape section and may be placed exterior to the lung parenchyma 106 and when positioned may be inferior to the distal portion 162 of the device. The proximal portion 163 of the device may be positioned within a patient's internal airway 110 such as in a bronchus. Furthermore, the device, with optional air intake component 165, may be placed, at any depth within the airway system 110 to fluidly connect to an area of hyper-inflation. It is alternatively envisioned that the device 150 could be used to deliver drugs such as bronchodilators that would locate the delivery of drugs in diseased and distal regions of the lungs 100 where drug is most needed.

[0045] The expandable structure 164 may comprise an exterior structure that define the voided space 170 within. The structure be for example a cage, a basket, a mesh, a wire structure, a weave, or a stent that can be delivered in a thin, undeployed state and expanded to a deployed state having an increased volume. As shown in Figure 6A, the expandable structure 164 comprises filaments, wire or struts deployed into an expanded state. In some embodiments, the structure expands to form a substantially spherical distal end with a relatively narrow proximal end. In some embodiments, the device 150 has length approximately equal to the largest diameter of the expandable structure 164 and the neck of the proximal end 163. The neck of the device 150 may also flare slightly at the proximal end 163 of the device 150. This flaring may serve an anti-migration function as the enlarged distal and proximal ends form a locking mechanism to fix the expandable structure in place. In an alternative embodiment, it is also envisioned that the proximal end of the device may comprise a second basket 160 structure, similar to the one located at the distal end. This envisioned embodiment is at least shown in an exemplary form in Figure 6B. Such configurations provide an advantage over conventional devices that may be displaced by natural movements including activity, breathing, sneezing, coughing, etc. In addition, as the device 150 is fully implanted, the second basket 160 structure may prevent occlusion from either opening of the device 150.

[0046] The airway bypass device 150 may be made from a biocompatible, flexible material such as Nitinol, stainless steel, silicon, Pebax, PEEK, polypropylene, a composite of multiple materials or other biocompatible materials, such as biocompatible polymers. In specific embodiments, it may be advantageous to infuse or coat the expandable structure 164, as well as other parts of the device 150, to accommodate drug or chemical delivery. Figure 6A provides contrasting views of two embodiments, with and without an air intake component. In some embodiments, the air intake component may not be required. Embodiments depicted with air intake component are also envisioned alternatively with the intake component replaced by a fluid passageway.

[0047] It is understood that an air intake component 165 may be placed within the expandable structure 164, if needed, as determined by a user or practitioner. The air intake component 165 may increase the surface area for gas exchange, which may help to prevent device failure from occlusion or other complications. In an alternative embodiment, it may be advantageous to configure the expandable structure to act as an electrode for energy, including RF, delivery. Application of RF energy may be used to ablate tissue in proximity to the device to assist in cleaning and/or device removal. Alternately, it may be advantageous for the basket structure to be made with a bioabsorbable material that remains long enough to define the pocket or void in parenchyma.

[0048] Alternatively, the expandable structure 164 may be made of a biocompatible polymeric knitted mesh made from a material such as polypropylene or polyester. Alternatively, the cage may be made from biodegradable or biodis solvable material such as polylactic-co-glycolic acid (PLGA) or alginate, which may dissolve after a period of time leaving a cavity in the lung parenchyma allowing air to continue venting through the device 150 or allowing the device 150 to be removed. Alternatively, the expandable structure 164 or at least the basket 160 may be made of Nitinol wires, or Nitinol wires coated with a polymer, such as polypropylene or polyester, or a biodegradable polymer. In a further embodiment, the components of the expandable structure 164 may be impregnated with one or more drugs that is released over time. The release may coincide with the degradation of the structure. Multiple biodegradable drugs impregnated components of the expandable structure 164 may have distinct degradation profiles to release a drug at a desired rate based on each specific profiles. The members of the expandable structure 164 and specifically the basket 160 (e.g., cage) may also be configured to move or deform (e.g., expand, contract) within the lung tissue 106 as the lung tissue moves due to inhalation, exhalation, or other potential causes of displacement.

[0049] In some embodiments, it may be advantageous to deploy devices 150 with a maximally sized expandable structures 164 that is able to pass through the working channel of a bronchoscope 130. A larger expandable structure may help to prevent tissue occlusion and provide a greater surface area for gas exchange. In at least one embodiments, the maximum width of the device may vary, but is envisioned to be less than 10mm in width. In other embodiments, the device width may be between 3 to 5 mm in diameter. In larger embodiments, that may be advantageous is larger bronchial vessels, the device is envisioned to have a width between 5mm and 10mm, 10mm and 20mm, or 10mm and 50mm. In certain implementations, the device is envisioned to be customized based on patient size with volume ranges including:

- from 40 to 1500 mm³, - from 40 to 1800 mm³,

- from 40 to 1000 mm³, - from 100 to 200 mm³,

- from 200 to 500 mm³,

- from 500 to 1000 mm³,

- from 1000 and 1800 mm³,

- from 1900 to 3000 mm³,

- from 2900 to 4000 mm³, or

- from 3900 to 5000 mm³.

[0050] Devices of various sizes may comprise a stem or neck, basket, and flare with dimensions scaled to maintain a consistent ratio. The device may be configured to have a slightly larger width at the narrow proximal tip. The diameter of this proximal tip may vary from patient to patient. The device is envisioned to have a sufficient quantity and sufficiently sized pores, such that the expandable structure 164 of the device stimulate fibrosis and tissue response and integrate into the tissue. For example, pore size of the basket 160 along with other areas of the device 150 may be between about .5 to 5 mm in width, or have a cross-sectional area between about 1 to 20 mm². Smaller envisioned embodiments may have pores of correspondingly reduced sizes. Alternatively, a temporary structure may be used to support the air space and control a healing process and then the temporary structure may be removed or be biodegradable. Alternative embodiments comprise other deployed shapes such as funnel, torus, ovoid, cylindrical, or irregular shapes. The expandable structure may be compliant (e.g., applying very little to no pressure or force on the tissue) except when it is being deployed.

[0051] As shown in the schematic of Figure 7, it may be advantageous in some cases for the expandable structure 164 and basket 160 to be produced using methods that neither form nor require kinks, junctions, welds or combinations thereof. Wire free from these forms is uniform and less brittle, which helps to reduce the risk of breakage and trauma from sharp or inconsistent edges. In one envisioned embodiment, the expandable structure 164 or basket 160 may be woven from a single wire that begins and terminates on the proximal end of the expandable structure 164 (i.e. nearer the neck) with some weave material overlapping the terminuses. To smooth these areas further, it is envisioned in at least one exemplary embodiment that the shaded area of Figure 7 may be covered with a membrane 172 or other material to reduce contact with tissue and to slow or prevent tissue ingrowth. The size and shape of the membrane 172 may vary, as needed. At least one further envisioned advantage of such an embodiment is the positioning of terminuses on the proximal end of the expandable structure 164. Any non-uniform structure may increase the risk of tissue irritation or inflammation that could lead to undesired tissue regrowth. Another envisioned advantage of such an embodiment is that a continuously formed or extruded wire is free from joints, junctions, or welds, which may result in fewer structural inconsistencies and imperfections. In some cases, the wire could be formed on a mandrel. In an alternative embodiment, the expandable structure 164 could be photo etched, joined or welded on a single end, in some cases with all welds or junctions located at the proximal end of the device and wrapped in a membrane 172 that causes minimal tissue trauma.

[0052] As an alternative, a space 170 can be created in the parenchyma of the lung 106 by deploying an expandable device such as a balloon or an injected bolus of biodegradable polymer. The expandable device can be then withdrawn and the support basket, or cage deployed to control healing processes and prevent closure of the space. Such alternatives are also envisioned to be deliverable with the use of modified endoscopes (e.g. bronchoscopes 130) in a minimally invasive manner.

[0053] The expandable structure 164 may be deployed gradually to control the healing process and minimize inflammation, bleeding and granulation. For example volume of the space created may be increased gradually over several hours, days or weeks by expanding in small increments until the fully deployed state is reached (e.g., 0.25 to 1.0 mL once every few days up to a fully deployed volume between about 3 to 20 mL (e.g., about 14 mL). The expandable structure 164 may be deployed with a balloon (e.g., compliant balloon) inside the expandable structure.

[0054] In an alternative embodiment, an expandable structure 164 may be configured to deploy by applying tension to a pull wire connected to a distal end of the expandable structure 164 to reduce the axial length of the expandable structure. The expandable structure 164 may be configured to respond to decreased axial length by increasing in diameter. For example, the structures forming the expandable structure or basket 160 may be made from an elastic material such as Nitinol, or an expandable structure 164 may be a wire weave or knitted or mesh structure or elastic stent-like structure. The pull wire passes through a pull wire hole in an air intake component and pass through a lumen in a conduit to a proximal region of the device external to the patient where a proximal portion of the pull wire is terminated in an end piece. In some embodiments, a depth stopper such as a collet may be used to adjust the tension on the pull wire and thus the diameter of the expandable structure 164 and the volume of the space 170 created by the expandable structure 164. The position of the depth stopper on the proximal portion of the balloon catheter may indicate the degree of deployment of the expandable structure.

[0055] In at least one aspect, the expandable structure 164 may be configured to be at a deflected pitch in its undeployed state. In this envisioned embodiment, the deployed expandable structure would be positioned normal (i.e. perpendicular) to the chest wall when fully deployed, while perpendicular depth within the lung would be significantly reduced in its undeployed state. The expandable structure 164 may be dimensioned to reduce the depth needed to accommodate the device in its undeployed state by further envisioned routes. In one envisioned embodiment, the expandable structure 164, a single-strand weave or basket may be dimensioned with a relative pitch (i.e. pitch relative to other strands) to reduce the overall length of the undeployed device 150, even if the resulting structure may have non-spherical or reduced volume when fully deployed.

[0056] Alternatively, once delivered, the expandable structure 164 may create a space 170 by expanding into a deployed shape that is dictated by physical features of the tissue surrounding the expandable structure. For example, a compliant expandable structure may expand by compressing tissue that is preferentially compressible or more flexible or softer and deform around tissue that is less compressible or less flexible or harder. This characteristic may further improve the ability to create a space in lung tissue with minimal irritation and inflammation that could lead to tissue regrowth that could clog the air pathway through the natural airway bypass device 150. The proper pore size is selected to prevent or suppress tissue to close the bridge or close the pore opening. It is desired that the pores remain open after tissue healing.

[0057] Other embodiments of devices or methods may be envisioned that create a space around an air intake component while creating an unfavorable environment in the space for tissue proliferation so air can pass unobstructed by tissue regrowth into the air intake component and out of the lung. The above examples gradually increase volume of a space created by inserting an expandable structure then altering its shape. Alternatively, volume may be gradually increased by gradually introducing a greater portion of a space creating device.

[0058] A distal region of a natural airway bypass device 150 may optionally comprise an energy delivery element to deliver energy such as electric, thermal, mechanical, or acoustic to facilitate control of healing processes or manipulate tissue characteristics such as the ability to recoil or expand and contract during breathing. In addition, such an element may be used to dislodge the device 150 from ingrowth tissue to assist in an extraction procedure, as needed.

[0059] An expandable structure may help to maintain a space around the air intake component by reinforcing a perimeter of the space. Tissue surrounding the space may contain channels 171 or air pathways that connect the space to parts of the lung containing trapped air as shown in Figure 4C. Healing processes may cause tissue to adhere or grow on to the expandable structure. However, a certain amount of tissue growth over the perimeter of the space is permissible without impeding airflow in to the air intake component.

[0060] As described, the expandable structure 164 may be covered by a material or membrane 172. In addition to covering only the neck and proximal portions 163 of the cage, the membrane may partially, selectively or fully cover the device 150. Such a material or membrane could be permanent, removable, bio-degradable or absorbable and may prevent or impede tissue growth. In a further embodiment, the membrane 172 may comprise one or more layers or materials infused with drugs. Drug elution from a membrane 172 may be possible with or without the degradation of the membrane. The material or membrane can provide added structural support to the device 150. In one envisioned embodiment, the material or membrane coverage encapsulates roughly one or more spherical caps or domes of the expandable structure 164. In a further embodiment, a dome over the proximal portion of the expandable structure prevents or deters tissue growth on the air tissue component 165. In particular, this embodiment may be advantageous given the potential contact the component makes with lung tissue 106 in addition to potential contact with lung tissue or the chest wall.

[0061] The air intake component 165 is a passageway for air to flow from the space 170 created in lung tissue by an expandable structure 164 to a lumen in the conduit 161. A natural airway bypass device 150 may be configured to allow air to pass in one direction only. For example, a valve 174 positioned in the device such as at a proximal region 163 of lumen 169 or in an air intake component may allow air to flow out of the body only. Alternatively, a device 150 may be configured to allow fluids (e.g. air, agents, saline) to pass from the distal region to the proximal region or from the proximal region to the distal region. For example, a device 150 may be absent a valve or a valve may be removable or be bypassed or opened when desired. It may be advantageous for the valve to be a one-way valve, or check valve. It may be desired to inject fluid from the proximal region of the device 150 to the distal region of the device 150 or space in the lung tissue. For example, it may be desired to inject a sterile fluid (e.g. air, mist, drug) to ensure tissue is not growing around air intake ports 168, to clean the space around the air intake component, or to deliver an agent to help maintain patency of the air passage ways, control healing processes, dilute air passageways, or treat infection or inflammation. Fluid injected to the distal region may pass through the air intake component 165 or alternatively through other ports 173.

[0062] The air intake component 165 may comprise one or more ports 168 to at least one lumen in the conduit. For example, the combined area of the port(s) may be greater than the cross sectional area of the lumen in the conduit 161. The air intake port may be held in the space 170 created by the expandable structure 164 and away from the lung tissue surrounding the space to reduce the chance of tissue growing into the ports 168 or of the air intake component irritating the tissue. An air intake component may further comprise ports 173 connected to other lumens in the conduit 161 that may be used for example to deliver an agent to the space 170 for example to protect against infection or maintain patency of the space or airway connections to the lung. An air intake component may be made from a biocompatible polymer such as silicon, polyurethane or Pebax of soft durometer and may be an extruded tube. Regarding polymer selection, as it generally relates to the invention, in particular embodiments, it may be advantageous to select a material that may be coated or infused with an antimicrobial. In at least one embodiment, the air intake component 173 may be a Pebax tube with ports 168 machined or melted into the tube and edges may be rounded, for example during the forming process or after creation of the holes.

[0063] In an advantageous embodiment, the airway bypass device 150 may be guided and positioned within the pulmonary system. A user or practitioner may use medical imaging techniques to determine the nearest accessible dead space or bulla 222. The device 150 may be positioned in the bronchiole by various delivery devices or systems. In some embodiment, the delivery system may use introducer sheaths, guide wires, cannulas or catheters, to deliver the device in a minimally invasive manner. Figure 8 shows two devices deployed in the distal region of the pulmonary system. It is further envisioned, as shown in figures 9 and 10 that a modified endoscope, catheter visualization device, or bronchoscope may be use in both the guidance and the placement of the device 150. In this scope-delivery method, it is envisioned that the delivery mechanism may be further modified to include one or more conventional introducer or guidance components.

[0064] While any endoscopic device may be modified for delivery, in the embodiment, the use of a specialized lung visualization catheter, or bronchoscope is envisioned. The bronchoscope-delivery method first comprises determining the approximate size of the delivery catheter that will hold the device. The size of the delivery catheter determines the size of the lumen required, which can be selected from standard bronchoscope sizes. The bronchoscope is then inserted into a sedated patient and advanced endotracheally into the bronchial network. The user or practitioner may steer the scope by manipulating the housing or handle shown in Fig 9 that is configured to remain external to the patient. The bronchoscope can provide internal visualization of the network or may be visualized using conventional radio imagining techniques. Visualization ensures that the manipulations performed by the user or practitioner to the distal end of the bronchoscope guide the scope to the appropriate location within the lung.

[0065] Once the bronchoscope 130 has been placed, the delivery sheath 120 or catheter, as shown in Figure 11A, may be loaded with the airway bypass device 150 at its distal end. The airway bypass device 150 is loaded in collapsed form into the working channel 131 of the scope 130 and maintains its compact shape until it is appropriately positioned. The delivery catheter may be further configured with a sheath 120 to provide an additional means for holding the airway bypass device 150 in collapsed form until it has reached its delivery location. The delivery catheter is then advanced through the bronchoscope 130. In some embodiments, the proximal end of the delivery catheter may be configured to lock with the handle 132 or housing of the bronchoscope 130. It is envisioned that this or another mechanism may be used to place a limit on the advancement of the delivery catheter or to stabilize the locked unit to ease the delivery process.

[0066] Once the delivery catheter has reached a desired location, as determined by a user or practitioner, the airway bypass device 150 may be deployed, in a manner similar to the one shown. The airway bypass device 150 will exit the sheath 120 at the distal tip, optionally following a previously deployed guide wire. These and other delivery mechanisms are not shown. Figure 1 IB shows the handle 132 of the scope 130 also including a handle 132 with a user interface 134. The interface 134 may separately control a scope advancement and the release of a pull wire, in addition to actuating any other delivery mechanisms. A pull wire, or strands that may be used to remove the delivery sheath 120 may also be found, as shown at the distal tip of Figure 11C. As the sheath is removed upon delivery of the device, the pull wires or strands shown are not present in the delivered device.

[0067] Figures 12A-12E show the step-wise deployment of the device as the expandable structure 164 regains shape once it is sufficiently released from the delivery catheter and the distal 120 sheath. For visualization purposes, an air intake component 165 is shown, but may be absent, replaced by a fluid passage, in some embodiments. If additional airway bypass devices 150 are to be deployed, the bronchoscope 130 placement, working channel 131 loading and delivery via delivery catheter and sheath may be repeated, as needed. Once the device 150 or devices are fully deployed, as seen in Figure 12E, the delivery catheter and bronchoscope may be carefully removed and post-operative procedures completed.

[0068] While the device is designed to remain within the patient for an extended period of time, it may, in some instances, be necessary or desirable to remove an airway bypass device for the vessel in which it has been deployed. In these cases, the airway bypass devices 150 configured to collapse when a sheath 120 is applied to the proximal side of the expandable structure 164. This method of treatment through implantation of an airway bypass device 150, is further envisioned to benefit from techniques that will minimize or avoid tissue regrowth that interferes with device performance, minimize or avoid device rejection, and minimize or avoid irritation of tissue interacting with the device. It may also be important to note that, while the order or arrangement of the components might be interchangeable, there may be an arrangement or multiple arrangements that are advantaged, as described.

[0069] In this disclosure, the terms "comprise" or "comprising" do not exclude other elements or steps, the terms "a" or "one" do not exclude a plural number, and the term "or" means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.

[0070] While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s).

Claims

CLAIMS WE CLAIM:

1. A device for airway bypass of a diseased lung dimensioned to be deployed through the working channel of a bronchoscope comprising: a distal region (162) configured for placement within lung parenchyma (106), and a proximal region (163) configured for placement in an airway (110), wherein the distal region (162) comprises an expandable structure (164), a conduit (161) connecting the distal region (162) to the proximal region

(163), wherein a lumen (169) in the conduit (161) fluidly communicates between the distal region (162) and the proximal region (163).

2. A device for airway bypass of a diseased lung dimensioned to be deployed through the working channel of a bronchoscope comprising: a distal region (162) comprising expandable structure (164) with a basket (160), and a proximal region (163) comprising a neck (155), wherein the neck extends from the basket (160) and is connectable to a conduit (161) extending through the wall of an airway (110), wherein a lumen (169) in the conduit (161) fluidly communicates between the distal region (162) and the proximal region (163), and wherein the device is formed of at least one wire (190) which forms the neck (155), and the basket.

3. A device according to claim 1 or 2, wherein the expandable structure

(164) surrounding an air intake component (165).

4. A device according to any one of the preceding claims, wherein the expandable structure (164) is configured for creating a space (170) within the lung parenchyma and separate the lung parenchyma from the air intake component

(165) .

5. A device according to according to claim 3 or 4, wherein the air intake component (165) comprises one or more ports (168) to said lumen (169) in the conduit (161).

6. A device according to claim 5, wherein the expandable structure (164) is configured for creating a surface area around the perimeter of said space (170) that is substantially greater than the area of the ports (168) in the air intake component (165).

7. A device according to any one of the preceding claims, wherein the expandable structure (164) is configured to temporarily contract.

8. A device according to any one of the preceding claims, wherein the expandable structure (164) comprises an outer structure (167) formed of one or more wires or filaments, defining the space (170) within, wherein the outer structure (167) may comprise at least one single wire that may include at least one section, which extends through the proximal end (163) without passing into the neck (155) and at least one other section, which extends through the proximal end (163) and into the neck (155).

9. A device according to any one of claims from 2 to 8, wherein the expandable structure is expandable from a sufficiently reduced undeployed state for advancement through the working channel of the bronchoscope, to an expanded, deployed state, having an increased volume.

10. A device according to any one of claims from 2 to 9, wherein expandable structure (164) is one of: a cage, a mesh, a basket, a weave, or a stent, and are made from a biocompatible material, or composite of multiple biocompatible materials, optionally wherein the struts are made from one or more of:

- Nitinol,

- stainless steel,

- silicon,

- Pebax,

- PEEK,

- other biocompatible polymer.

11. A device according to any one of the preceding, wherein the space (170) maintained by the expandable structure (164) in fully deployed state has a volume which is one of:

- from 40 to 1500 mm³, - from 40 to 1800 mm³, - from 40 to 1000 mm³, - from 100 to 200 mm³,

- from 200 to 500 mm³,

- from 500 to 1000 mm³,

- from 1000 and 1800 mm³,

- from 1900 to 3000 mm³,

- from 2900 to 4000 mm³, - from 3900 to 5000 mm³.

12. A device according to any one of the preceding claims, wherein the expandable structure (164) is configured to deliver a biologically active compound.

13. A device according to any one of the preceding claims, wherein the expandable structure (164) is configured to be gradually expanded in increments.

14. A device according to any one of the preceding claims, wherein the air intake component (165) defines a passageway for air to flow to a lumen in the conduit (161).

15. A device according to any one of the preceding claims wherein the airway bypass device is configured to allow air to pass in one direction only, optionally wherein a valve positioned in the device such as at a proximal region (163) of lumen (169) or in an air intake component allows air to flow out.

16. A device according to any one of claims 3 to 15, wherein the air intake component (165) comprises further ports (173) connected to other lumens in the conduit (161).

17. A device according to any one of claims 3 to 16 wherein the air intake component (165) is on a distal portion of an elongate tube that is inserted, optionally in a removable manner, through the lumen (169) of the conduit (161) and into the space of the expandable structure (164).

18. A device according to claim 17, wherein the elongate tube comprises a lumen (161) for passage of air from the air intake component (165) to the proximal region (163) of the device.

19. A device according to any one of the preceding claims comprising a strain relief member connecting the conduit (161) to the air intake component (165).

20. A device according to any one of the preceding claims, wherein the conduit (161) comprises a replaceable inner sleeve configured to be inserted into the lumen (169) of the conduit (161).

21. A device according to any one of the preceding claims comprising an energy delivery element connected to the device and configured to deliver energy to the device such as electric, thermal, mechanical, or acoustic, and a computerized controller configured to apply energy to the device for example in the form of electrical energy, thermal energy, vibration, or acoustic energy.

22. A device according to any one of the preceding claims comprising a manual user interface (134) or automated controller connected to the device and configured to control gradual expansion of the expandable structure (164).

23. A device according to any one of the preceding claims, wherein the expandable structure in fully deployed state is a spheroid with diameter in a range of 0.5-7cm.

24. A device according to any one of the preceding claims, wherein the expandable structure (164) has pores sized so that basket (160) of the structure may further stimulate fibrosis and tissue response and integrate into the tissue.

25. A device according to any one of the preceding claims wherein the expandable structure further comprises a membrane layer (172), the membrane layer (172) comprising one or more orifices configured to allow air to pass from the lung parenchyma (106) to the space (170) and out of the lung parenchyma (106) through the lumen (169).

26. A method for venting trapped air of a diseased lung comprising: inserting an implantable artificial air passage configured to be temporarily collapsed and inserted through the airway (110) wall through the working channel (131) of a bronchoscope (130) and into a lung (100) of a patient; displacing lung parenchyma (106) in the lung (100) by expanding an expandable structure (164) of the artificial passageway, wherein the expandable structure (164) is permeable to the passage of air from the lung parenchyma (106); positioning a conduit (161) with a lumen (169) within the expandable structure wherein the conduit (161) is positioned within a volume formed in the lung parenchyma (106) by the expanding expandable structure (164) and fluidly connected to a position in the airway (110) of the patient.

27. The method of claim 26 wherein the expandable structure (164) includes a basket (160), optionally formed of wire, and the displacement of the lung parenchyma (106) includes expanding the basket (160) from a compressed configuration in which the basket (160) is adjacent a shaft including the air intake device (165) to an expanded configuration which displaces the wire mesh radially outward from the shaft.

28. The method of claim 26 further comprising identifying a lung region of lung parenchyma (106) having one or more characteristics including: low density lung parenchyma, collateral ventilation channels (218) and a lack of major blood vessels, and the displacement of the lung parenchyma (106) is in the identified lung region.

29. The method of claim 26 wherein the expandable structure (164) is permeable and allows permeation of air from the lung parenchyma (106) to the air device over a period of time of at least six (6) months.

30. A system for venting trapped air of a lung through an airway wall comprising: a bronchoscope (130) with working channel (131) to be advanced down the airway (110) of a patient, and an implantable artificial air passage device configured to be temporarily collapsed and inserted through the airway (110) wall through the working channel (131) of the bronchoscope (130), the system including an expandable structure configured to displace lung parenchyma (106) and form a space within the expandable structure (164) and an air intake device (165) positioned within the space (170), and a conduit (161) extending from the air intake device (165) or lumen (161) through to the airway (110) of the patient.

31. The system according to claim 30 further comprising a handle (132) attached to a proximal end of the bronchoscope (130), wherein the handle (132) may include a user interface (134) or a user activation device or trigger (136) configured to actuate the deployment the artificial passageway

32. The system of claim 31 wherein a delivery sheath (120) may be positioned around the air passage device to temporarily collapse the device.

33. The system of claim 30 further comprising a membrane (172) over the surface of the expandable structure (164), and wherein the membrane (172) includes pores having on average a cross-sectional area between 1 to 100 mm².

34. The system of claim 32 wherein the membrane (172) is on at least one of an outer surface or inner surface of the expandable structure (164).

35. The system of claim 34 further comprising a porous membrane layer (172) adjacent the expandable structure (164).

36. The system of claim 35 wherein the membrane layer (172) may be elastic and provide flexure to dampen forceful movements.

37. The system of claim 35 wherein the membrane layer (172) comprises a biodegradable layer and a non-biodegradable layer, the nonbiodegradable layer comprising orifices and the biodegradable layer covering at least a portion of the orifices.