The field of the invention is lung volume reduction devices used to treat hyper-inflated lung, for example in patients diagnosed with chronic obstructive pulmonary disease (COPD), emphysema, asthma, bronchitis. The invention relates to lung volume reduction devices such as deployable valves configured to be delivered through the airway to the lung with minimally invasive techniques.
Hyper-inflated lung is a lung disease that makes it hard to breathe. COPD is a major cause of disability and is the third leading cause of death in the United States. The symptoms and effects of COPD often worsen over time, such as over years, and can limit the ability of a person suffering from COPD to do routine activities. Current medical techniques offer no solution for reversing the damage to the airways and lungs associated with COPD.
COPD often does not affect all air sacs or alveoli equally in a lung. A lung may have diseased regions in which the air sacs are damaged and unsuited for gas exchange. The same lung may have healthy regions (or at least relatively healthy regions) in which the air sacs continue to perform effective gas exchange. The diseased regions may be large, such as 20 to 30 percent or more of the lung volume.
The diseased regions of the lung occupy volume in the pulmonary cavity, which could otherwise be occupied by the healthy portion of the lung. If the healthy regions(s) of the lung were allowed to expand into the volume occupied by the diseased regions, the healthy regions could expand and fill with air to allow the air sacs in the healthy region to exchange oxygen for carbon dioxide.
In U.S. Patent Application Publication 2014/0058433 describes methods and devices are adapted for regulating fluid flow to and from a region of a patient's lung, such as to achieve a desired fluid flow dynamic to a lung region during respiration and/or to induce collapse in one or more lung regions. Pursuant to an exemplary procedure, an identified region of the lung is targeted for treatment. The targeted lung region is then bronchially isolated to regulate airflow into and/or out of the targeted lung region through one or more bronchial passageways that feed air to the targeted lung region.
U.S. Pat. No. 7,842,061 discloses an intra-bronchial device placed and anchored in an air passageway of a patient to collapse a lung portion associated with the air passageway. The device includes a support structure, an obstructing member carried by the support structure that reduces ventilation to the lung portion by preventing air from being inhaled into the lung portion, and at least one anchor carried by the support structure that anchors the obstruction device within the air passageway. The anchor may engage the air passageway wall by piercing or friction, include a stop dimensioned for limiting the piercing of the air passageway wall, and may be releasable from the air passageway for removal of the intra-bronchial device. The anchors may be carried by a peripheral portion of the support structure, or by a central portion of the support structure. The obstructing member may be a flow control valve.
International Publication Number WO 2004/010845 discloses a flow control device for a bronchial passageway. The device can include a valve member that regulates fluid flow through the flow control device, a frame coupled to the valve member, and a membrane attached to the frame. At least a portion of the flow control device forms a seal with the interior wall of the bronchial passageway when the flow control device is implanted in the bronchial passageway. The membrane forms a fluid pathway from the seal into the valve member to direct fluid flowing through the bronchial passageway into the valve member.
However, there remains a need for a lung volume reduction device and procedure that effectively treats patients suffering from a hyperinflated lung that is also affordable, quick to implant, easily assessable and removable, and safe.
This disclosure is related to methods, devices, and systems for reducing volume of a hyper-inflated lung, for example in a patient suffering from COPD.
One aspect of the disclosure is a device for reducing volume of a patient's diseased lung lobe comprising a proximal end, a distal end, a deployable structural frame, a sealing element, a valve, and a retention element. The device may be embodied as an endobronchial valve, such as a lobar flow control valve. These functions may be served by distinct structures or in some embodiments one or more structures may provide one or more of these functions.
The structural frame may further comprise a coupler on its proximal end. The coupler may be configured to mate with a delivery tool and transmit torque and translation applied to the delivery tool to the device.
The endobronchial valve, such as a lobar flow control valve, may have a sealing element that is a flexible membrane connected to the structural frame.
The endobronchial valve may include a flow control valve that permits air to flow in a direction from the distal end to the proximal end.
Also disclosed herein is a method of treating a patient with COPD comprising delivering a lobar valve through a working channel of a bronchoscope and deploying the lobar valve in a lobar bronchus that feeds a diseased lobe of the patient's lungs so that the lobar valve permits air to be released from the diseased lobe and air is not permitted to pass into the diseased lobe. The method may further comprise affixing a retention element of the lobar valve to an airway carina distal to the lobar bronchus. The retention element may be an airway carina screw or an airway carina clip. The valve may be positioned in the lobar bronchus such that the axis of the valve is not parallel with the axis of the lobar bronchus.
One or more further aspects of the disclosure are provided below.
A first aspect relates to a flow control device for a bronchial passageway comprising: a flow control valve; a braided wire structural frame, wherein the structural frame is expandable from a collapsed configuration to an expanded configuration, and in the collapsed configuration the frame is an extended tube and in the collapsed configuration the frame includes a wall contact section, a middle support section within the wall contact section, and a fold between and connecting the wall contact section and the middle support section; and a sealing membrane mounted to at least a distal portion of the structural frame, wherein the sealing membrane forms an enclosed wall defining at least a portion of an airflow passage through the flow control device, and the flow control valve is included in the airflow passage and extending inward from the enclosed wall and at least partially within the wall contact section.
A 2nd aspect relates to the flow control device of the first aspect, wherein the flow control valve is integrated in the sealing membrane.
A 3rd aspect relates to the flow control device of the 1st or 2nd aspect, wherein the flow control device further comprises a coupler and spokes extending radially outward from the coupler to a proximal end of the braided wire structural frame.
A 4th aspect relates to the flow control device of the 1st to 3rd aspects, wherein the wall contact section is longer than the middle support section.
A 5th aspect relates to the flow control device of the 1st to 3rd aspects, wherein the braded wire structural frame includes an inner support section connected to the middle support section by a second fold.
A 6th aspect relates to the flow control device of the 5th aspect, wherein the middle support section is longer than the inner support section.
A 7th aspect relates to the flow control device of the 5th to 6th aspects, wherein the inner support section is directly connected to spokes extending radially inward of the inner support section to a coupler.
An 8th aspect relates to the flow control device of the 1st to 7th aspects, wherein a width of the braided wire structural frame, in the expanded configuration is in a range of 7 mm to 12 mm or in a range of 5 mm to 15 mm or in a range of 11 mm to 14 mm or in a range of 10 mm to 18 mm.
A 9th aspect relates to the flow control device of the 1st to 8th aspects, wherein a length of the flow control device in the expanded configuration is in a range of 8 mm to 18 mm.
A 10th aspect relates to the flow control device of the 1st to 9th aspects, wherein the structural frame, while in the expanded configuration, includes a cylindrical airway wall contact section.
An 11th aspect relates to the flow control device of the 10th aspect, wherein at least a part of the sealing membrane is bonded to the cylindrical airway contact section.
A 12th aspect relates to the flow control device of the 10th aspect, wherein the sealing member covers the cylindrical airway wall contact section and spokes included in the structural frame.
A 13th aspect relates to the flow control device of the 1st to 12th aspects, wherein the structural frame, in the collapsed configuration has a diameter no greater than 2.6 mm.
A 14th aspect relates to the flow control device of the 1st to 13th aspects, wherein the structural frame, in the collapsed configuration has a diameter in a range of 2 mm to 2.6 mm.
A 15th aspect relates to the flow control device of the 1st to 14th aspects, wherein a ratio of a length to a width of the structural frame in the expanded configuration is in a range of 0.28:1 to 0.54:1, such as about 0.417:1.
A 16th aspect relates to the flow control device of the 1st to 14th aspects, wherein a ratio of a width of the structural frame in the expanded configuration to the width in the collapsed configuration is in a range of 4:1 to 7:1, such as about 5.45:1.
A 17th aspect relates to the flow control device of the 1st to 16th aspects, wherein the flow control device includes a coupler at a proximal end of the device.
An 18th aspect relates to the flow control device of the 1st to 17th aspects, wherein the flow control device includes a coupler at a proximal end of the device, and the coupler is configured to connected to a corresponding coupler of a shaft of a delivery device.
An 19th aspect relates to the flow control device of the 18th aspect, wherein the coupler is formed from a laser cut tube.
A 20th aspect relates to the flow control device of the 19th aspect, wherein the laser cut tube has a wall thickness in a range of 0.11 mm to 0.17 mm.
A 21st aspect relates to the flow control device of the 19th aspect, wherein the laser cut tube also forms spokes connected to the braided wire structural frame.
A 22nd aspect relates to the flow control device of the 1st to 21st aspects, wherein the sealing membrane has a micropattern molded at least on the exterior surface of the airway wall contact section, the micropattern configured to be hydrophilic.
A 23rd aspect relates to the flow control device of the 1st to 22nd aspects, wherein sealing membrane has a micropattern molded on at least one of the interior surface of the airway contact section and the flow control valve, the micropattern configured to increase hydrophobic nature of the sealing membrane.
A 24th aspect relates to the flow control device of the 1st to 23rd aspects, wherein the ratio of the diameter of the flow control device in the collapsed configuration to the diameter of the flow control device in the expanded configuration is in a range of 1:10 to 2:10
A 25th aspect relates to the flow control device of the 1st to 24th aspects, wherein the delivery length is in a range of 30 to 40 mm and the deployed length is in a range of 8 to 18 mm.
A 26th aspect relates to the flow control device of the 1st to 25th aspects, further comprising at least one anti-inversion feature within the flow control valve.
A 27th aspect relates to the flow control device of the 26th aspect, wherein the anti-inversion feature is a at least one joint, such as a weld, between opposite lips of the flow control valve.
A 28th aspect relates to the flow control device of the 26th or 27th aspects, wherein the at least one anti-inversion feature occupies only portion of a width between opposite side edges of the lips of the flow control device.
A 29th aspect relates to the flow control device of the 26th to 28th aspects, wherein the at least one anti-inversion feature cumulatively occupies a width in a range of 5% to 25% of a width between opposite side edges of the lips of the flow control device.
A 30th aspect relates to the flow control device of the 26th to 29th aspects, wherein each of the at least one anti-inversion feature has a width in a range of 0.3 to 1.5 mm and the flow control valve has a width in a range of 7 mm to 10 mm.
A 31st aspect relates to the flow control device of the 26th to 30th aspects, wherein the at least one anti-inversion feature joins opposite lips of the flow control valve at the distal ends of the lips.
A 32nd aspect relates to the flow control device of the 26th to 31st aspects, wherein the at least one anti-inversion feature is in a range of 0.5 to 3 mm from a plane of an inlet to the flow control valve.
A 33rd aspect relates to the flow control device of the 26th to 32nd aspects, wherein the flow control device includes opposing lips, and an inside surface of at least one of the lips is dimpled in a region proximate to the at least one anti-inversion feature.
A 34th aspect relates to the flow control device of the 1st to 34th aspects, wherein the wall contact section, in the expanded configuration, is oval in cross-section, and the flow control valve is elongated in cross-section.
A 35th aspect relates to the flow control device of the 34th aspect, wherein major axes of the cross-section of the wall contact section and of the flow control valve are parallel.
A 36th aspect relates to the flow control device of the 34th to 35th aspects, wherein semi-major axes of the cross-section of the wall contact section and of the flow control valve are parallel.
A 37th aspect relates to the flow control device of the 34th to 36th aspects, wherein opposite lips of the flow control valve are aligned with the major axis.
A 38th aspect relates to the flow control device of the 34th to 37th aspects, wherein the flow control device parts along a line parallel to the major axis.
A 39th aspect relates to the flow control device of the 34th to 38th aspects, wherein a surface area of a portion of the sealing membrane spanning a distal end of the braided wire structural frame is in a range of 5% to 15% greater than an area circumscribed by the distal end of the braided wire structural frame in the expanded configuration.
A 40th aspect relates to the flow control device of the 1st to 39th aspects, wherein a ring surrounds the flow control valve and the ring is integral with the sealing membrane.
A 41st aspect relates to the flow control device of the 40th aspect, wherein the ring has a stiffness greater than a stiffness of the sealing membrane radially outward of the ring.
A 42nd aspect relates to the flow control device of the 40th to 41st aspects, wherein the ring has a thickness greater than a thickness of the sealing membrane radially outward of the ring.
A 43rd aspect relates to an assembly of an air flow control device and an insertion tool for a bronchial passageway comprising: air flow control device, wherein each of the air flow control devices includes: a flow control valve; a braided wire structural frame, wherein the structural frame is expandable from a collapsed configuration to an expanded configuration and the braided wire structural frame in the collapsed configuration is an elongated tube and in the expanded configuration includes a wall contact section, a middle support section residing radially within the wall contact section, and a first fold between the wall contact section and the middle support section; a sealing membrane mounted to at least a distal portion of the structural frame, wherein the sealing membrane forms an enclosed wall defining at least a portion of an airflow passage through the flow control device, and the flow control valve is included in the airflow passage, and a first coupler at a proximal end of the airflow control device; a delivery sheath configured to be positioned in a bronchial passageway, wherein the delivery sheath includes a distal end, wherein the air flow control device, while in the collapsed configuration, is within the delivery sheath; a delivery shaft within the delivery sheath and extends through the delivery sheath towards the distal end; and a second coupler at the distal end of the delivery shaft, wherein the second coupler is configured to securely engage the first coupler, wherein the delivery shaft is configured to advance through the delivery sheath to push the air flow control device from the distal end of the delivery sheath and into the bronchial passageway, wherein the air flow control device is configured to expand from the collapsed configuration into the expanded configuration after the air flow control device is pushed out of the delivery sheath, and wherein the air flow control device is configured to automatically release from the second coupler when an actuator on a handle of the assembly is actuated.
A 44th aspect relates to the assembly of aspect 43, further comprising a visual marker on a distal region of the delivery sheath, wherein the visual marker indicates an angular position of a semi-minor or semi-major axis of the braided wire structural frame.
A 45th aspect relates to an implantable airflow control device for a lobar bronchus comprising a distal end and a proximal end, a braided Nitinol frame, and a membrane affixed to a distal end of the frame, and wherein the airflow control device expands from a collapsed state to an expanded state, and the frame in the collapsed configuration is an elongated tube and in the expanded configuration includes a wall contact section, a middle support section residing radially within the wall contact section, and a first fold between the wall contact section and the middle support section.
A 46th aspect relates to the device of aspect 45, wherein the braided frame, comprises a wall contact section, a first fold, a middle support section residing radially within the wall contact section, and a second fold.
A 47th aspect relates to the device of aspect 46, wherein the middle support section resides radially within the wall contact section when the device is in its expanded state and adjacent to the wall-contact section when the device is in its collapsed state.
A 48th aspect relates to the device of the 46th or 47th aspects, wherein the middle support section is shorter than the wall contact section.
A 49th aspect relates to the device of the 46th or 47th aspects, further comprising an inner support section.
A 50th aspect relates to the device of the 49th aspects, wherein the inner support section resides radially within the middle support section when the device is in its expanded state and adjacent to the middle support section when the device is in its collapsed state.
A 51st aspect relates to the device of the 49th or 50th aspects, wherein the inner support section is shorter than the middle support section.
A 52nd aspect relates to the device of the 46th to 51st aspects, wherein the braided Nitinol frame comprises a first braid angle in at least the wall-contact section and a second braid angle in at least the first fold.
A 53rd aspect relates to the device of the 52nd aspect, wherein the first braid angle is less than the second braid angle.
A 54th aspect relates to the device of the 46th to 53rd aspects, wherein the wall-contact section has a length in a range of 8 mm to 18 mm when the device is in its expanded state.
A 55th aspect relates to the device of the 46th to 54th aspects, wherein the device has a diameter in a range of 7 mm to 12 mm or in a range of 5 mm to 15 mm or in a range of 11 mm to 14 mm or in a range of 10 mm to 18 mm when the device is in its expanded state.
A 56th aspect relates to the device of the 46th to 55th aspects, wherein the device has a diameter in a range of 2 to 2.6 mm in its collapsed state.
A 57th aspect relates to the device of the 46th to 56th aspects, wherein the device has a length to diameter ratio in a range of 0.28:1 to 0.54 to 1 in its expanded state.
A 58th aspect relates to the device of the 46th to 57th aspects, wherein the device has a diameter in the expanded state to a diameter in the collapsed state ration in a range of 4:1 to 7:1, such as about 5.45:1.
A 59th aspect relates to the device of the 46th to 58th aspects, wherein the braided Nitinol frame comprises closed loop ends at its distal end.
A 60th aspect relates to the device of the 59th aspects, wherein the closed loop ends are bent inward toward a central axis of the device in its expanded state.
A 61st aspect relates to the device of the 58th to 60th aspects, in combination with aspect 46, wherein the closed loop ends have an angle that is less than a braid angle of the wall-contact section.
A 62nd aspect relates to the device of the 58th to 61st aspects in combination with aspect 46, wherein at least a portion of the closed loop ends alternate in length.
A 63rd aspect relates to the device of the 47th to 62nd aspects, wherein the first fold has a bend radius in a range of 0.75 mm+/−0.5 mm.
A 64th aspect relates to the device of the 46th to 63rd aspects, wherein at least a portion of wires forming the braided Nitinol frame are connected to a coupler.
A 65th aspect relates to the device of the 64th aspect, wherein at least a portion of the wires connected to the coupler are bound together to form spokes.
A 66th aspect relates to the device of the 65th aspect, wherein the device comprises 3 to 15 spokes.
A 67th aspect relates to the device of the 64th to 66th aspects, wherein each pair of adjacent spokes define a space.
A 68th aspect relates to the device of the 67th aspect, wherein each space has an area in a range of 5 mm2 to 40 mm2.
A 69th aspect relates to the device of the 65th to 68th aspects, wherein the spokes have lengths in a range of 5 to 15 mm.
A 70th aspect relates to the device of the 65th to 69th aspects, wherein the spokes have lengths in a range between a radius of the targeted bronchus to 3 mm more than the maximum diameter of the targeted bronchus.
A 71st aspect relates to the device of the 65th to 70th aspects, wherein all of the spokes have equal lengths.
A 72nd aspect relates to the device of the 65th to 71st aspects, wherein the spokes have a shape set S-curve.
A 73rd aspect relates to the device of the 65th to 72nd aspects, wherein the braided Nitinol frame comprises at least one Nitinol wire.
A 74th aspect relates to the device of the 73rd aspect, wherein the Nitinol wire has a diameter in a range of 0.003″ to 0.007″.
A 75th aspect relates to the device of the 73rd to 74th aspects, wherein the Nitinol wire has a transition temperature less than 32° C.
A 76th aspect relates to the device of the 46th to 75th aspects, further comprising barbs.
A 77th aspect relates to the device of the 46th to 76th aspects, further comprising barbs protruding radially outward from the braided Nitinol frame while in the expanded state and not protruding radially outward from the structural frame while in the collapsed state.
A 78th aspect relates to the device of the 77th aspect, wherein the barbs extend at an angle acute to a longitudinal axis of the device.
A 79th aspect relates to the device of the 77th to 78th aspects, wherein some of the barbs are angled towards a distal end of the flow control device and others of the barbs are angled towards a proximal end of the flow control device.
An 80th aspect relates to the device of the 77th to 79th aspects, in combination with aspect 47, wherein at least some of the barbs extend from spokes of the structural frame.
An 81st aspect relates to the device of the 77th to 80th aspects, in combination with aspect 46, wherein at least some of the barbs extend from the wall-contact section of the frame.
An 82nd aspect relates to the device of the 65th to 81st aspects, wherein the coupler is positioned at the proximal end of the device, and the coupler is configured to connected to a corresponding coupler of a shaft of a delivery device.
An 83rd aspect relates to the device of the 82nd aspect, wherein the coupler comprises a threaded lumen.
An 84th aspect relates to the device of the 46th to 83rd aspects, further comprising a flow control valve.
An 85th aspect relates to the device of the 46th to 84th aspects, wherein the membrane comprises a wall-contact section and a flow control valve.
An 86th aspect relates to the device of the 84th to 85th aspects, wherein the flow control valve is positioned at the distal end of the device.
An 87th aspect relates to the device of the 46th to 86th aspects, wherein the membrane further comprises a lumen occluding section between the wall-contact section and the flow control valve.
An 88th aspect relates to the device of the 46th to 87th aspects, wherein the membrane comprises a hydrophilic micropattern surface at least on the external surface of the wall-contact section.
An 89th aspect relates to the device of the 46th to 88th aspects, wherein the membrane comprises a hydrophobic micropattern on the internal surface of the wall-contact section or on the flow control valve.
A 90th aspect relates to the device of the 46th to 89th aspects, wherein the membrane is bonded to the braided Nitinol frame with a bonding substrate.
A 91st aspect relates to the device of the 90th aspect, wherein the bonding substrate has a thickness in a range of 5 to 10 microns.
A 92nd aspect relates to the device of the 46th to 91st aspects, wherein the membrane has a thickness in a range of 30 to 50 microns.
A 93rd aspect relates to the device of the 85th to 92nd aspects, wherein the wall contact section of the membrane is bonded to the exterior surface of the wall-contact section of the braided Nitinol frame.
A 94th aspect relates to the device of the 46th to 93rd aspects, wherein the membrane is bonded to the braided Nitinol frame on selected regions of the wall-contact section of the braided Nitinol frame, wherein the selected regions comprise less than 100% of the wall contact section.
A 95th aspect relates to the device of the 94th aspect, wherein the selected regions comprise at least one band around the circumference of the braided Nitinol frame.
A 96th aspect relates to the device of the 94th aspect, wherein the selected regions comprise at least one longitudinal strip on the wall-contact section of the frame.
A 97th aspect relates to the device of the 94th aspect, wherein the selected regions comprise of spots.
A 98th aspect relates to the device of the 46th to 97th aspects, wherein the membrane is made from an elastomer.
A 99th aspect relates to the device of the 46th to 98th aspects, wherein the membrane has a modulus of elasticity in a range of 10 to 20 MPa.
A 100th aspect relates to the device of the 84th to 99th aspects, wherein the flow control valve is a duckbill or Heimlich valve.
A 101st aspect relates to the device of the 84th to 100th aspects, wherein the flow control valve has two lips.
A 102nd aspect relates to the device of the 84th to 101st aspects, wherein the flow control valve opens when air pressure is greater on the distal end than on the proximal end of the device.
A 103rd aspect relates to the device of the 84th to 102nd aspects, wherein the flow control valve controls air to flow predominantly out through the lobar bronchus.
A 104th aspect relates to the device of the 84th to 103rd aspects, wherein the flow control valve has a diameter less than the diameter of the braided Nitinol frame in its expanded state.
A 105th aspect relates to the device of the 84th to 104th aspects, wherein the flow control valve has a diameter in a range of 2.5 to 4.5 mm.
A 106th aspect relates to the device of the 84th to 105th aspects, wherein the flow control valve has a diameter that is 15% to 30% of the diameter of the braided Nitinol frame in its expanded state.
A 107th aspect relates to the device of the 84th to 106th aspects, wherein the flow control valve has a length in a range of 3 mm to 7 mm.
A 108th aspect relates to the device of the 84th to 107th aspects, wherein the flow control valve and the membrane are fabricated together as one component.
A 109th aspect relates to the device of the 45th to 108th aspects, further comprising an airflow resistance adjustment element.
A 110th aspect relates to the device of the 109th aspect, wherein the airflow resistance adjustment element is a tube or rod.
A 111th aspect relates to the device of the 109th or 110th aspects, wherein the airflow resistance adjustment element is biodegradable.
A 112th aspect relates to the device of the 46th to 111th aspects, wherein the wall-contact section has a length in a range of 8 mm to 18 mm.
A 113th aspect relates to an implantable airflow control device for a bronchial passageway comprising: an airflow control valve; a braided wire structural frame expandable from a collapsed configuration to an expanded configuration; and a sealing membrane mounted to at least a distal portion of the structural frame, wherein the sealing membrane forms an enclosed wall defining at least a portion of an airflow passage through the flow control device, and the flow control valve is included in the airflow passage.
A 114th aspect relates to the implantable airflow control device of aspect 113, wherein the airflow control valve is within the braided wire structural frame.
A 115th aspect relates to the implantable airflow control device of aspect 113 or 114, wherein the braided wire structural frame comprises a wall contact section, a first fold, a middle support section radially within the wall contact section and connected to the wall contact section by the first fold, and a second fold connected to the middle support section.
A 116th aspect relates to the implantable airflow control device of aspect 115 wherein the middle support section resides radially within the wall contact section when the airflow control device is in the expanded state and adjacent to the wall contact section when the airflow control device is in the collapsed state.
A 117th aspect relates to the implantable airflow control device of aspects 115 or 116, wherein the middle support section is shorter than the wall contact section.
A 118th aspect relates to the implantable airflow control device of any aspects 113 to 117, further comprising an inner support section connected to the second fold and radially within the middle support section when the device is in the expanded state and adjacent to the middle support section when the device is in the collapsed state.
A 119th aspect relates to the implantable airflow control device of aspect 118, wherein the inner support section is shorter than the middle support section.
A 120th aspect relates to the implantable airflow control device of any aspects 115 to 119, wherein the braided wire structural frame comprises a first braid angle in at least the wall-contact section and a second braid angle in at least the first fold.
A 121st aspect relates to the implantable airflow control device of aspect 120, wherein the first braid angle is less than the second braid angle.
A 122nd aspect relates to the implantable airflow control device of any aspects 115 to 121, wherein the wall-contact section has a length in a range of 8 mm to 18 mm when the device is in the expanded state.
A 123rd aspect relates to the implantable airflow control device of any aspects 113 to 122, wherein the braided wire structural frame has a diameter in a range of 7 mm to 12 mm or in a range of 5 mm to 15 mm or in a range of 11 mm to 14 mm or in a range of 10 mm to 18 mm while the airflow control device is in the expanded state.
A 124th aspect relates to the implantable airflow control device of any aspects 113 to 123, wherein the braided wire structural frame has a length to diameter ratio in a range of 0.28:1 to 0.54 to 1 while in the expanded state.
A 125th aspect relates to the implantable airflow control device of any aspects 113 to 124, wherein the braided wire structural frame has a diameter in the expanded state to a diameter in the collapsed state ration in a range of 4:1 to 7:1, such as about 5.45:1.
A 126th aspect relates to the implantable airflow control device of any aspects 113 to 125, wherein a braided wire forms closed loops at an end of the braided wire structural frame.
A 127th aspect relates to the implantable airflow control device of aspect 126, wherein a plurality of the closed loop ends bend inward toward a central axis of the braided wire structural frame.
A 128th aspect relates to the implantable airflow control device of any aspects 126 or 127, wherein a plurality of the closed loop ends have an angle less than a braid angle of the wall-contact section.
A 129th aspect relates to the implantable airflow control device of any aspects 115 to 128, wherein the first fold has a bend radius in a range of 0.75 mm+/−0.5 mm.
A 130th aspect relates to the implantable airflow control device of any aspects 113 to 129, wherein wires forming the braided wire structural frame form a wall contact section and spokes extending from the wall contact section to a coupler which is releasably attached to the airflow control device.
A 131st aspect relates to the implantable airflow control device of aspect 130 wherein a space is defined between a pair of adjacent ones of the spokes, and the space has an area in a range of 5 mm2 to 40 mm2.
A 132nd aspect relates to the implantable airflow control device of aspect 130, wherein the spokes each have lengths in a range of 5 to 15 mm.
A 133rd aspect relates to the implantable airflow control device of any aspects 113 to 132, wherein the braided wire structural frame includes a wall contact section and the sealing-membrane covers an outer surface of the wall contact section.
A 134th aspect relates to the implantable airflow control device of aspect 133, wherein the wall-contact section has a length in a range of 8 mm to 18 mm.
A 135th aspect relates to the implantable airflow control device of any aspects 133 to 134, wherein the sealing membrane further comprises a lumen occluding section between the wall-contact section and the airflow control valve.
A 136th aspect relates to the implantable airflow control device of any aspects 122 to 135, wherein the membrane comprises a hydrophilic micropattern surface at least on the wall-contact section or the airflow control valve.
A 137th aspect relates to a flow control device for a bronchial passageway comprising: a flow control valve; a structural frame, wherein the structural frame is expandable from a collapsed configuration to an expanded configuration; a sealing membrane mounted to the structural frame, wherein the sealing membrane forms an enclosed wall defining at least a portion of an airflow passage through the flow control device, and at least one anti-inversion feature within the flow control valve.
A 138th aspect relates to the flow control device of aspect 137, wherein the anti-inversion feature is a at least one joint, such as a weld, between opposite lips of the flow control valve.
A 139th aspect relates to the flow control device of any aspects 137 or 138, wherein the at least one anti-inversion feature occupies only portion of a width between opposite side edges of the lips of the flow control device.
A 140th aspect relates to the flow control device of any aspects 137 to 139, wherein the at least one anti-inversion feature cumulatively occupies a width in a range of 5% to 25% of a width between opposite side edges of the lips of the flow control device.
A 141st aspect relates to the flow control device of any aspects 137 to 140, wherein each of the at least one anti-inversion feature has a width in a range of 0.3 to 1.5 mm and the flow control valve has a width in a range of 7 mm to 10 mm.
A 142nd aspect relates to the flow control device of any aspects 137 to 141, wherein the at least one anti-inversion feature joins opposite lips of the flow control valve at the distal ends of the lips.
A 143rd aspect relates to the flow control device of any aspects 137 to 142, wherein the at least one anti-inversion is in a range of 0.5 to 3 mm from a plane of an inlet to the flow control valve.
A 144th aspect relates to the flow control device of any aspects 137 to 143, wherein the flow control device includes opposing lips, and an inside surface of at least one of the lips is dimpled in a region proximate to the at least one anti-inversion feature.
A 145th aspect relates to the flow control device of any aspects 137 to 144, wherein the wall contact section, in the expanded configuration, is oval in cross-section, and the flow control valve is elongated in cross-section.
A 146th aspect relates to the flow control device of aspect 145, wherein major axes are parallel of the cross-section of the wall contact section and of the flow control valve.
A 147th aspect relates to the flow control device of any aspects 145 or 146, wherein semi-major axes are parallel of the cross-section of the wall contact section and of the flow control valve.
A 148th aspect relates to the flow control device of any aspects 145 to 147, wherein opposite lips of the flow control valve are aligned with the major axis.
A 149th aspect relates to the flow control device of any aspects 145 to 148, wherein the flow control device parts along a line parallel to the major axis.
A 150th aspect relates to the flow control device of any aspects 145 to 149, wherein a surface area of a portion of the sealing membrane spanning a distal end of the braided wire structural frame is in a range of 5% to 15% greater than an area circumscribed by the distal end of the braided wire structural frame in the expanded configuration.
A 151st aspect relates to the flow control device of any aspects 137 to 150, wherein a ring surrounds the flow control valve and the ring is integral with the sealing membrane.
A 152nd aspect relates to the flow control device of aspects 151, wherein the ring has a stiffness greater than a stiffness of the sealing membrane radially outward of the ring.
A 153rd aspect relates to the flow control device of aspects 151 or 152, wherein the ring has a thickness greater than a thickness of the sealing membrane radially outward of the ring
The disclosure herein is related to systems, devices, and methods for modifying air flow to and from a targeted portion of a patient's lung, which may be substantially diseased, with an implantable device in order to reduce the volume of trapped air in the targeted portion of lung, thereby increasing the elastic recoil of the remaining lung volume.
The authors/inventors conceived of and disclose herein, implantable lung volume reducing devices and medical techniques for implanting lung volume reduction devices through the trachea and bronchi, using minimally-invasive deployment, bronchoscopic and surgical techniques. The device may be embodied as an endobronchial valve. In some embodiments the endobronchial valve may be intended for implant in a lobar bronchus and is referred to as a lobar valve or lobar flow control valve.
Also disclosed is a novel treatment for patients suffering from hyper-inflated lung (e.g., emphysema, COPD, bronchitis, asthma) comprising the application of a minimally invasive bronchoscopy technique to implant a lung volume reduction device into a lung airway of a patient. The implantable lung volume reduction devices, which may be generally referred to as “lobar valves” disclosed herein are intended to be placed in an airway trunk of a lobe such that a single valve regulates air flow to or from the complete lobe, which may have benefits over previously attempted valves that were intended for multiple valve placement in higher generation airways. Benefits of a lobar valve may include lower cost, faster procedure, easier implantation, easier removal, less risk of pneumothorax due to slower lobe volume reduction, and stronger retention. However, some features of devices disclosed herein may be novel and useful for use in higher generation airways and are not limited to devices configured for placement in a trunk of a lobe.
Anatomy and Design Inputs and Challenges:
Lobar valves may be implanted in a secondary bronchus, also known as a lobar bronchus. Humans have one lobar bronchus providing air passage to each lobe of the lung, including three in the right lung and two in the left lung. The right-side lobar bronchi include the right upper lobar bronchus 44, right middle lobar bronchus (not shown for simplicity), and right lower lobar bronchus 46. The left side lobar bronchi include the left upper lobar bronchus 50 and left lower lobar bronchus 52, both of which divide into tertiary bronchi 54. Overlapping cartilage plates of the lobar bronchi provide structural strength to maintain patency of these bronchi. Typically, a lobar bronchus has a protruding cartilage ring 63 near the proximal end of the lobar bronchus. Humans may typically have lobar bronchi having an average diameter in a range of 6 mm to 18 mm. The average length is about 19 mm (e.g., in a range of about 8 to 40 mm).
Lobar valves disclosed herein are transitionable from a contracted delivery state to an expanded deployed state. In the contracted delivery state the lobar valve is compressed and constrained in a delivery sheath that can be advanced through a bronchoscope working channel. When advanced out of the delivery sheath the lobar valve transitions toward its expanded state, for example via elastic properties of a structural frame, until constrained by the brochus in which it is implanted. The circumference of the lobar valve in its unconstrained, expanded state may be larger than the circumference of the targeted airway where it is implanted, so that a radial force is applied by the lobar valve to the airway wall.
A lobar valve 100 may assume its contracted delivery state when delivered through a working channel of a bronchoscope, optionally contained in a delivery sheath and manipulated with a delivery tool. The lobar valve and optional delivery sheath and delivery tool may be sized to pass freely through a working channel of a bronchoscope. For example, a lobar valve adapted to be delivered with a delivery tool through a working channel with a 2.8 mm lumen may have a maximum diameter of 2.6 mm (e.g., a maximum diameter of 2.5, 2.4, 2.3, 2.2. 2.1 mm). In some embodiments lobar valves may comprise a structural frame having a delivery state and deployed state, wherein the delivery state has a maximum diameter in a range of 2 (0.0787″) to 2.5 mm (0.0984″), preferably 2.11 mm (0.083″).
Ease of use and procedural expediency is a desired requirement. The lobar valve may be designed to be consistently delivered to a correct location with average physician skill. Compared to valves that are implanted at higher generation airways implanting a lobar valve may be a faster procedure because only one valve needs to be implanted to affect an entire lobe, the lobar bronchi are larger, more proximal and hence easier to access and find than distal higher generation bronchi. Also, assessing the function of a single implanted lobar valve is faster and easier compared to assessing multiple distally implanted valves.
A lobar valve and procedure for implanting one may cost less compared to implanting multiple higher generation valves in particular since there is only one device to implant and the procedure is faster.
Design considerations may also consider particular challenges for placement in a lobar bronchus. For example, the length of a lobar bronchi is relatively short, the length to diameter ratio is considerably smaller, the cross section of a lobar bronchus is radially asymmetrical (e.g., ovular or irregular), and the diameter of the lumen is inconsistent along the length of the lobar bronchus (e.g., flared at the proximal, distal or both ends). Potentially, a single lobar valve placed in a lobar bronchus may experience a greater air pressure difference between its proximal and distal sides compared to a plurality of valves positioned in several higher generation bronchi of a lobe.
Furthermore, each particular lobar bronchus in a patient has unique characteristics such as the angle of approach and geometry.
Structural Frames:
The structural frame provides a framework to hold the membrane and valve in a desired orientation and position in a target bronchus. The structural frame applies an outward radial force to press the membrane against the airway wall and hold the flow control valve in the airway so air is directed through the flow control valve.
The structural frame 101 may be made by braiding wires into at least a generally cylindrical shape. The generally cylindrical shape of the structural frame can constitute an airway wall contact region 110 that is intended to expand to contact the airway wall and to flexibly conform to the surface of the airway wall. The wires may be elastically or super-elastically flexible with shape memory ability, for example the wires may be made from Nitinol that is superelastic above a temperature of body temperature (about 37° C.) or lower. As the braided wire structural frame transitions from the delivery state to deployed state the device diameter (excluding optional radially extending barbs) increases from a first device diameter 111′ (
The wires used to form the structural frame braid may be for example superelastic Nitinol wires having wire diameter in a range of 0.003″ to 0.008″ (preferably in a range of 0.005″ to 0.006″). The structural frame 101 may have a braid angle 117 in a range of 35° to 55° (see
In some embodiments the wires are braided with a closed loop 113 at the distal end 115 of the device as shown in
Optionally, in the unconstrained state the closed loop ends 113 may be bent inward toward the central axis to relieve forces and friction applied by the ends to the airway wall to reduce the risk of irritating the tissue which may cause granulation tissue or injury.
To accommodate lobar bronchi having an average circumference in a range of 22 mm to 44 mm multiple lobar valves may be provided. For example, a large size lobar valve may have a frame with an airway contact section having a diameter in a range of about 15 to 20 mm, preferably about 16 mm (a circumference of 50.24 mm), which may be intended to be placed in lobar bronchi having a circumference in a range of 31 mm to 44 mm; and a smaller sized lobar valve may have a frame with an airway contact section having a diameter in a range of about 11 mm to 13 mm, preferably about 12 mm (a circumference of 37.7 mm), which may be intended to be placed in lobar bronchi having a circumference in a range of 22 mm to 33 mm. Note that the lobar valves may generally have a maximum unconstrained circumference that is larger than the circumference of the intended lobar bronchus (e.g., about 2 to 2.5 mm larger, about 10 to 20% larger) so that when constrained by the lobar bronchus the airway contact section of the frame firmly contacts the airway wall and applies an outward radial force against the airway wall via the elastic properties of the structural frame and optionally other features described herein that contribute to radial contact force. The target airway may be measured using CT or other medical imaging or with a sizing device delivered through a bronchoscope.
The ratio of the maximum outer diameter of the airway contact section in an unconstrained state to the maximum diameter of the constrained delivery state may be in a range of 3.8:1 to 7.8:1. Due to the relatively larger diameter and short length of lobar bronchi compared to higher generation airways, lobar valves may have a smaller length to diameter ratio in an expanded unconstrained state than current devices intended for more distal positioning. For example, a lobar valve may have a length in a range of 4 mm to 6 mm in its unconstrained state and a length to diameter ratio in a range of 0.545 to 0.286.
The structural frame along with the connected sealing membrane(s) in the delivery state may have a maximum diameter less than 2.7 mm (e.g., less than 2.6, 2.5, 2.4, 2.3, 2.2, 2.1 mm), preferably a maximum diameter of about 2.3 mm. Alternative embodiments of lobar valves may have different dimensions to allow them to be delivered through bronchoscope working channels having different diameters. Optionally, lobar valves in an unconstrained state may have a noncircular cross-section (e.g., ovoid, oval, irregular), which may have an improved fit in a bronchus having a noncircular cross-section. Alternatively, a lobar valve may be adapted to conform to a noncircular airway cross-section or irregular airway wall surface.
In situ, the structural frame may expand and contract with movement of the bronchus (e.g., during elastic recoil). The shape of the structural frame or use of its retention element may be resistant to tilting or may function properly when positioned in a range of angles with respect to the axis of the bronchus. Also, the structural frame may be compressed after it has been fully deployed allowing for repositioning. For example, a structural frame may be compressed by grasping or coupling a delivery tool to the frame's coupler and at least partially withdrawing it into a delivery sheath.
In its contracted delivery state, for example as shown in
Optionally or alternatively, a structural frame may be made from a bioresorbable material such as a polymer matrix (e.g., PLA, PLAGA, PDLLA).
Optionally or alternatively, a structural frame may be balloon expandable or made from a plastically deformable material such as plastic, cobalt chrome alloy, martensitic Nitinol, stainless steel, silicone or urethane.
Optionally or alternatively, a structural frame may be impregnated with an agent such as an antifungal, antibacterial, antimitotic, or anti-inflammatory agent that may improve patient response to implanting the device.
In these embodiments, the wall contact region 101 may be adapted to comply to lobar bronchi that have oval or irregular lumen cross sections; the device may comply to irregular airway surfaces creating a seal on surfaces having bumps, ridges, grooves or other non-smooth surface; the device may have an overall length that is suited for fitting in lobar bronchi.
The wall contact area 110 may have flexibility and elasticity to conform to non-cylindrical (e.g., irregular, oval, tapered, flared) or non-smooth (e.g., bumpy, ridged, contoured) airways or alternatively apply a greater contact force that causes the airway wall to deform or a combination of both in order to provide a continuous circumferential sealing band to prevent air leakage in to a targeted portion of the lung under pressure differentials normally experienced in the lung. When implanted in a target airway, a structural frame may be adapted to impart an outward contact force that may expand the airway wall no more than 20% which is expected to provide strong contact and a good air seal while avoiding trauma to the tissue that otherwise could cause excess formation of granulation tissue.
Optionally, a wall contact area 110 in its unconstrained state may be barrel shaped (e.g., have a wider middle than proximal and distal ends) or be flared (e.g., have a larger diameter distally than proximally), which may facilitate creating a good contact region and seal with the airway wall.
The wall contact region 110 of the structural frame 101 provides a scaffold for the membrane 102, which is affixed to the frame, for example by dip coating, adhesive, solvent bonding or other form of bonding. The structural frame may be collapsible to its contracted delivery state in an orderly fashion that does not damage the membrane.
Spokes
Optionally, a lobar valve may have radial spokes 116 that connect to the airway contact region 110 of the structural frame and extend inward toward the axis 118 where they may be connected to a hub or a coupler 109. In its compressed delivery state (
Coupler
The proximal end of the structural frame may comprise a coupler that mates with a delivery device that allows the coupler to transmit rotational and translational force from the delivery tool to the structural frame. The coupler may be used as a graspable protrusion to grasp with a bronchoscopic tool to manipulate the device during implantation, repositioning, or removal.
For example, a lobar valve 100 may optionally have a coupler 109, positioned at the proximal end 114 of the device, that functions to mate with a coupler of a delivery shaft 108 and release from the coupler of the delivery shaft upon actuation by a user. For example, the coupler may have a geometry (e.g., male or female threading) that mates with a coupler of the delivery shaft 108. An actuator (e.g., rotary dial, trigger, slider, button) controllable by a user for example on a handle connected to the delivery sheath and delivery shaft may control the delivery shaft and sheath to control release of the couplers (e.g., retract the sheath 105 and rotate the delivery shaft 108 to unscrew the mating coupler). When attached the coupler transmits motion of the delivery shaft to the implantable valve 100 including longitudinal translation distally, proximally and rotation around longitudinal axis 118.
In embodiments having spokes 116 a coupler 109 may also function to contain the terminals of the spokes.
Optionally, a coupler may be laser cut from a Nitinol hypotube, which may also form spokes and radially protruding retention barbs.
A coupler may have a length in a range of 1 to 4 mm (e.g., about 3 mm)
Covering/seal/membrane
Lobar valves disclosed herein may further have at least one membrane (102 in
The membrane connected to the structural frame may be made from a thin, flexible, durable, foldable, optionally elastic material such as urethane, polyurethane, ePTFE, silicone, Parylene, Elast-eon™ or a blend of multiple materials. Durometer of the membrane material may be in a range of 70 A to 85 A. The membrane may be made by insert molding, dip coating or spray coating a mold or other manufacturing methods know in the art of medical balloon or membrane manufacture. It may be bonded to the frame for example by coating the frame, laminating over the frame, dip coating, spray coating, heat staking, bonding with adhesive, solvent bonding, or sewing. For example, the membrane may have a thickness in a range of 30 to 50 microns thick and may be bonded to the structural frame with an adhesive substrate that has a thickness in a range of 5 to 10 microns, which may provide sufficient bonding strength while allowing sufficient flexibility of the flow control device so it can easily transition between its contracted and expanded states. Referring to
The sealing membrane may be positioned and bonded outside the structural frame. Alternatively, a sealing membrane may have an inner membrane layer bonded to the inner surface of the structural frame as well as an outer membrane layer bonded to an outer surface of the structural frame wherein the inner and outer layers may be bonded to one another between braid wires or spokes 116 thus encapsulating at least a portion of the structural frame.
Airflow 120 as shown in
Portions of the sealing membrane 102 framed by wires of the structural frame in the airway contact region 110 may be flexible and have slack that functions to facilitate air sealing by billowing out and applying contact pressure with the airway wall over a surface area defined by the sealing membrane portions when air is passing through the device or a pressure difference is higher within the device.
The sealing membrane 102 and structural frame 101, in particular the wall contact region 110, form a contact surface area that is continuous around a circumference of a targeted airway.
In an alternative embodiment of a sealing membrane the membrane may have channels that intentionally allow air to pass the seal in either direction initially after the device is implanted and gradually close to block air passage except for through a valve. For example, the channels may be positioned on the seal surface next to the airway wall and over time (e.g., a few weeks) become plugged with mucus that naturally exists in the airway. Gradual or delayed sealing could delay the evacuation of trapped air and subsequent lobar volume reduction so that shifting of the lobes of the treated lung occurs more gradually, which may be less likely to have adverse events such as pneumothorax or injury to healthy lung tissue.
Optionally, a membrane may deliver a chemical agent released slowly over time. For example, the membrane may deliver an antiseptic, antimicrobial or other agent, which may reduce the risk of infection, pneumonia, rejection or other complication. For example, a membrane may be impregnated with an agent such as an antifungal, antibacterial, antimitotic, or anti-inflammatory agent that may improve patient response to implanting the device.
Optionally, a membrane 102 may have a micropatterned surface that provides a non-stick or hydrophobic feature on the interior side (i.e., facing inward toward the axis 118) of the airway contact region 110, on the luminal covering section 119, on the valve, or a combination. The non-stick micropatterned surface may have a lubricious texture pattern which may reduce friction and repel or allow fluids such as mucous to slide off the membrane. As shown in
Optionally, a hydrophobic coating may be added to the interior side of the airway contact region 110, on the luminal covering section 119, on the valve, or a combination.
Optionally, a membrane 102 may have a micropatterned surface (e.g., hydrophilic) that provides increased friction on the exterior side of the airway contact region 110.
Flow control Valve
The lobar valve 100 is adapted to provide a seal that does not allow air to flow, or at least substantially increases resistance to airflow through the targeted airway except for through the flow control valve 103. The sealing function is achieved by the membrane 102 connected to the structural frame and the sealing membrane 102 may also form the flow control valve 103. Alternatively, a valve may be a separate structure bonded to the sealing membrane or structural frame. Generally, a valve is adapted to allow air to flow at least predominantly in one direction, from the affected lobe and not into it.
Optionally, a valve material may be impregnated with an agent such as an antifungal, antibacterial, antimitotic, or anti-inflammatory agent that may improve patient response to implanting the device.
As an example, a flow control valve 103 may be made from a flexible, non-stick material such as an elastomeric material, urethane, polyurethane, ePTFE, silicone, Parylene or a blend of multiple materials. The flow control valve 103 may be a duckbill or Heimlich valve having a somewhat funnel shape that transitions from a distal flared, or funnel-shaped end to a proximal closing end. The distal flared end may be tubular having an outer diameter that connects with the luminal covering region 119 of the sealing membrane 102. The distal flared end may have a height 121 in a range of 1 mm to 4 mm (e.g., 2 mm to 3 mm), and a width in a range of 8 to 10 mm. The length 122 of the flow control valve 103 may be in a range of 3 to 8 mm (e.g., 5 mm). The Heimlich valve 103 includes a pair of opposed, inclined walls having ends that meet at lips at the proximal closed end. The lips meet at two opposed corners and may be pinched flat. The walls can move with respect to one another so as to separate at the lips and form an opening through which fluid can travel. When exposed to fluid flow in a direction represented by the arrow 120 in
Optionally, a flow control valve 103 may be adapted to provide a desired exiting air flow resistance. It may be desired to release air from the target lobe slowly to reduce a risk of pneumothorax that can be caused by rapid deflation of the lobe. Exiting air flow resistance may be inversely proportional to the valve's lumen diameter proportional to its length and may be a function of material stiffness.
Any of the lobar valve embodiments disclosed herein may optionally have an airflow resistance modulation feature that initially and temporary allows some air to flow from the proximal end 114 to the distal end. This feature may function to slow down the volume reduction of the targeted lobe to reduce a risk of pneumothorax associated with rapid deflation. For example, the feature may be a biodegradable or dissolvable component that holds the flow control valve 103 partially open or provides a gap between the airway contact region of a device 100 and the targeted airway wall. The component may shrink or dissolve over an initial duration of time (e.g., in a range of 3 days to 3 weeks). Alternatively, a physician may implant the flow control device with an airflow resistance modulation feature in place and perform follow up procedure, for example within 3 days to 3 weeks following the initial implant procedure to block, remove or reposition the airflow resistance modulation feature, which may increase the resistance to inhalation. The physician may assess the rate of lobar volume decrease or integrity of the pleura following the initial implantation to determine if the airflow resistance should be increased. Furthermore, a physician may elect to decrease inhalation resistance even more if the targeted lobe is found to collapse too aggressively following an initial implant. This may be done in a follow up procedure that adds a different airflow resistance modulation feature that reduces resistance further. An airflow resistance modulation feature may be in a form of a tube positioned in the valve path that restricts how much the valve closes during inhalation either by holding the valve open or by providing a lumen in the tube through which air may flow. Alternatively, instead of a tube a soft rod (e.g., a rod made from a polymeric material such as silicone beading) may be used to prevent the valve from closing completely. Another alternative embodiment of an airflow resistance modulation feature is a hole in the membrane (e.g., positioned in the part of the membrane that covers the lumen of the airway) that may be filled when desired for example by applying an adhesive to fill the hole. Another alternative embodiment of an airflow resistance modulation feature involves a biodegradable suture that partially holds the valve open and allows the valve to fully close when the suture dissolves.
A flow control valve, for example a Heimlich or duckbill valve, optionally may have a feature that prevents the valve from inverting inside out, which otherwise could be caused by a higher pressure on the proximal side of the valve. For example, as shown in
Preferably, the remaining open portion of the flow control valve where air may flow has a width in a range of 7 to 10 mm to permit sufficient flow of exhaled air. An anti-inversion feature 336, 341, particularly those positioned in the center of the valve 307 may be positioned at a distance 340 from the distal flared end in a range of 0.5 to 3 mm (e.g., 0.6 to 1 mm).
In the exemplary embodiment shown in
The anti-inversion features 336, 337, 339, 341 may be formed by heat welding the two layers of membrane that form the flow control valve together. Optionally, this may involve a mandrel for holding the membrane or masking regions where welding is to be avoided. Alternatively, the anti-inversion features may be formed by applying adhesive between the membrane layers in the desired position.
Optionally, the lobar valves disclosed herein may have features that improve function when they are placed in lobar bronchi having oval or irregular transverse cross sections. For example, as shown in
Optionally, a lobar valve may have a structural fame that has an oval transverse cross-sectional shape with a semi-major axis and a semi-minor axis in its unconstrained deployed configuration and may also have a membrane with greater slack in a first direction in the luminal covering region, wherein the semi-major axis is aligned with the first direction. Furthermore, the flow control valve 307 having a lips that part along a parting line/plane 355 between the lips may be aligned so that the parting line is parallel to the major axis 350. This configuration may improve the function of the valve in an oval shaped bronchus. In a scenario where the patient coughs for example an oval-shaped bronchus may be compressed momentarily, typically causing a large reduction in the semi-minor axis of the bronchus. If a flow control valve is aligned so that the parting line 355 is oriented parallel to the semi-major axis of the bronchus as shown in
Retention Mechanism
A lobar valve may have a retention mechanism such as radial contact force, radially extending barbs, a micropatterned surface on the membrane, placement distal to cartilaginous rings, radial interference, or a combination of these. The retention mechanism functions to keep the device situated and oriented in the targeted position of the patient's airway. The device may be removed by applying force (e.g., pulling, torqueing) to the coupling element or structural frame to overcome the retention force. Alternatively, the retention mechanism may be released from the airway by collapsing the lobar valve.
Radial contact force applied by the airway contact region 110 to the airway wall can help to retain the device 100 in the desired implant location in a lobar bronchus by contributing to friction. Furthermore, radial contact force may distend the airway wall creating a niche for the device to sit in. Radial contact force may be created by the elastic properties of the structural frame 101 returning to its shape set configuration, which may be larger (e.g., 5 to 20% larger) than the airway. Additional radial contact force may be created by optional spokes 116.
A micropatterned surface on the polymeric membrane 102 at least in the airway contact region 110 may help to retain the device in place by resisting sliding on wet surfaces such as airway walls but not on dry surfaces such as through a delivery sheath. For example, a micropattern may be molded to the membrane using techniques known in the art (e.g., U.S. Pat. No. 8,720,047 assigned to Hoowaki, LLC). The micropatterned surface may increase water tension when contacting a wet surface which can greatly increase retention ability. The micropattern may have a plurality of pillars having height and width dimensions less than 1000 nanometers.
Placement of the device just distal to a cartilage ring in an airway may contribute to retention of the device. Cartilage rings exist in lobar bronchi in particular at the proximal end of lobar bronchi and may protrude from the airway surface where cartilage rings are absent. Since the structural frame is shape set to a larger size than the airway it elastically expands against the airway wall. To overcome the cartilage ring, the structural frame would have to reduce in size which goes against its elastically expanding nature.
As shown in
Alternatively, barbs 104 may be made from a laser cut hypotube. For example, a coupler, spokes and barbs may be made from a laser cut hypotube, wherein the spokes are connected to a braided structural frame forming an airway contact region.
Regardless of the retention mechanism embodied, a lobar valve 100 may be implanted and before removing the delivery tool and bronchoscope, a pull force test may be applied to the device to ensure it has been sufficiently anchored in place. With the delivery tool connected to a grasping mechanism of an implanted lobar valve, the pull force may be conducted by applying a gentle pull force on the delivery tool. A force gauge may indicate the amount of force applied to the lobar valve. If the valve becomes dislodged below a predetermined force, the retention mechanism of the stent may not suit the current implantation, a different sized device may be required, or the device may need to be repositioned.
A first embodiment of a lobar valve as shown in
The wires of the braided structural frame 101 have closed loop ends 113 on the distal side 115 and on the proximal side 114 the wires are gathered and shape-set to form the spokes 116. The terminals of the wires are held (e.g., crimped, welded) in the coupler 109.
Barbs 104 radially protrude from the proximal end of the airway contact region 110.
The spokes 116 may be angled proximally 114 as shown in
Optionally spokes 116 may be “S” shaped spokes 155 as shown in
Alternatively, as shown in
Alternatively, spokes and optionally a coupler or radial barbs may be made from a laser cut hypotube (e.g., Nitinol).
The optional barbs 104 may be formed from a variety of options disclosed herein such as separate wires from the braided structural frame connected to the spokes or airway contact region, wires forming the braided structural frame cut and shape set to protrude forming the barbs, or portions of the braided structural frame shape set to protrude outward.
An alternative embodiment 180 of a lobar valve is shown in
Another alternative embodiment of a lobar valve 205 is shown in
Optionally, as shown in
Another alternative embodiment of a lobar valve shown in
A sealing membrane 241 may be connected to the braided structural frame at least partially over the airway contact region 232 and a portion of the proximal luminal covering region 234 leaving an uncovered part 242 of the luminal covering region 234. A separate membrane flap 243 connected to the coupler 109 or structural frame temporarily covers the gap 242 and overlaps a portion of the membrane 241 when air pressure is higher on the proximal end 114 than the distal end 115. The flap 243 opens when pressure is higher on the distal end 115 than the proximal end 114. Thus, the flap 243 and membrane 241 act as a flow control valve.
Alternatively, the membrane 241 may partially cover the distal luminal covering region 238 and a flow control valve may be formed with a flap at the distal end also adapted to preferentially allow air flow from the distal to proximal ends (not shown).
Optionally, the membrane 241 at least on the exterior portion of the airway contact region 232 may have a molded micropattern 244 to increase retention in the airway.
Optionally, radially protruding barbs 245 may be connected to the braided structural frame 241. The barbs 245 may be one or more of the various embodiments of radially protruding barbs disclosed herein.
The braided structural frame forming both proximal 234 and distal 238 luminal covering regions may have increased strength or radial contact force with the airway wall in situ.
Another alternative embodiment of a lobar valve 260 is shown in
A sealing membrane 268 may be connected to the braided structural frame 261 on at least a portion of the airway contact region 267, where the membrane may optionally have a micropatterned surface on the exterior of the membrane to enhance retention in an airway. The membrane may also cover the luminal covering region 264 and form a flow control valve 269 (e.g., Heimlich or duckbill valve) in a lumen defined by the inner tube 266.
The embodiment shown in
Optionally, a thread or suture may be woven into the proximal end of the frame. The thread may be used to contract the structural frame, for example the thread may be grasped with bronchoscopic forceps and pulled to contract the proximal end of the support frame to pull the device into a delivery sheath for initial loading or re-positioning. Optionally, the thread may be connected to a ball (e.g., threaded through a hold in the ball) that functions as a grasping element. The ball may be relatively small, e.g., between about 1 mm and 3 mm.
An exemplary embodiment of a lobar valve 300 is shown in a cross-sectional illustration in
The braided frame 303 is generally tubular or cylindrical in shape and has a wall contact section 310, a first fold 311 on the proximal side of the wall-contact section, a middle support section 312 that fits inside the wall contact section, a second fold 313, and an optional inner support section 314 that fits inside the middle support section. The wall-contact section 310, first fold 311, middle support section 312, second fold 313 and, optional inner support section 314 may be fabricated by braiding at least one Nitinol wire that is superelastic at body temperature. The folds may be fabricated by shape-setting the Nitinol wire or Nitinol braid.
Optionally the folds 311 or 313 may have a braid angle that is different than the braid angle in the wall contact section 310, middle support section 312 or inner support section 314.
The wall-contact section 310 has a length 316 in a range of 8 mm to 18 mm. The middle support section 312 may have a length 317 that is shorter than the wall-contact section length 316. For example, in the expanded configuration shown in
The distal end of the wall-contact section may comprise closed end loops 319 formed by the Nitinol wire. Optionally, the closed end loops 319 may have features of closed end loops disclosed elsewhere such as 125 shown in
Embodiments having the inner support section 314, may have spokes 315 connecting the proximal end of the inner support section 314 to the coupler 304. The spokes may be fabricated from the same wires that are braided to form the inner support section and rest of the braided frame. For example, the wires continuing from the braided the inner support section may be bundled into groups (e.g., groups of 3, of 4, of 5, of 6) to form the spokes. There may be a total of 3 to 15 spokes for example. The bundled groups of wires have adequate strength and stiffness so force applied at the coupler by a delivery tool can push the device out of a delivery sheath, pull the device back into a sheath, or manipulate the placement of the device. Also, bundling the wires at this location provides large spaces 321 between the spokes 315 at the proximal end of the device where the membrane is not located, which can allow fluid such a mucus to escape from the space in the device. The spokes 315 may have a length when straightened (see
A similar embodiment 324 of a lobar valve but without an inner support section is shown in
Optionally, barbs may be connected to the braided Nitinol support structure 303 or fabricated from some of the wires forming the support structure 303. The retention elements may have features of barbs 104 disclosed herein.
The coupler 304 may be connected to the spokes 315, for example by crimping the bounded wires forming the spokes into the coupler. The coupler is adapted to be releasably connected to a delivery tool, for example via mating threads or mating geometry. The coupler 304 may have other features disclosed herein for couplers 109.
The membrane 305 is connected to the outward face of the wall contact section 310 of the braided Nitinol frame 303 and extends at the distal end 302 of the device inward toward the central axis 306 to block the lumen in the airway and hold a flow control valve 307 in the airway lumen. Airflow through the airway lumen is directed by the membrane 305 through the flow control valve 307. The valve and membrane may be the same material and component. The configuration shown in
The valve 307 (
A method of implanting the flow control device 300 may comprise advancing a delivery sheath 105 through the patient's airway to a target lobar bronchus; advancing the flow control device 300 partly from the delivery sheath to deploy the wall contact section 310 and optionally the first fold 311; placing the wall contact section in the target lobar bronchus and allowing the wall contact section to contact a wall of the lobar bronchus (adjustments in position may be made by advancing or retracting the delivery sheath 105 while keeping the delivery tool 108 and portion of the lobar valve 300 stationary with respect to the delivery sheath); then advancing the flow control device further from the delivery sheath to deploy the first fold, the middle support section, and the second fold. If the flow control device 300 further comprises an inner support section 314, the inner support section may also be advanced from the sheath following the step of allowing the wall contact section to contact the wall of the lobar bronchus. If the targeted lobar bronchus has a cartilage ring at its proximal end, the step of placing the wall contact section in the target lobar bronchus may comprise placing the wall contact section distal to the cartilage ring and optionally placing the first fold 311 distal and adjacent to the cartilage ring. The flow control device may be advanced from the sheath by pushing the flow control device with a delivery tool or holding the delivery tool stationary with respect to the patient's lung and retracting the delivery sheath. The delivery tool may be coupled to the flow control device, for example with screw threads, and may be decoupled from the flow control device, for example by rotating the delivery tool to unscrew it from the coupler, while the flow control device is held in place by the targeted airway.
As shown in
Optionally, the braid angle at the first fold 311 or locking ring 330 may be larger than the braid angle in the flat sections (e.g., wall-contact section 310, middle support section 312, or inner support section 314) of the frame 303. The larger braid angles at the folds may provide the following: greater radial forces that may provide a better retention feature; and lower bend radii at the folds that may make it easier to collapse the device and load it into a delivery sheath.
Optionally, the first fold 311 or second fold 312 may be made during a shape set process by bending the wires around mandrels.
Another characteristic of the device shown in
Delivery Tool
As shown in
An alternative embodiment of a delivery shaft, may have a central lumen, which may be used for delivery over a guidewire or to pass over or deliver other instruments such as an endoscope. Optionally a delivery shaft may have a mandrel extending distally, which may be used to hold a valve to the delivery shaft, to add coupling force, to target a coupler of a lobar valve when retrieving it or to adjust its position.
Optionally, the delivery tool may have a delivery sheath 282 used in conjunction with the delivery shaft 280. The sheath may constrain the valve in a delivery state during delivery through a working channel as shown in
Optionally, the delivery tool may have a handle 283 at a proximal region that has an actuator (e.g., thumb lever) that controls a sliding translational movement of the shaft 280 with respect to the sheath 282 facilitating one-handed control for advancing a valve out of a sheath or retracting it into the sheath. For example, a sheath 282 may be connected to the handle body and a shaft 280 may be slidably engaged in the sheath and connected to a gear that is movable (e.g., rotation or translation) within the handle and moved by a mating gear connected to an actuator such as a thumb lever, slider, or rotary dial. The handle may have one or more actuators that move the delivery shaft and control the position of the lobar valve from a fully contained position as shown in
Kit
Optionally a lobar valve may be provided preloaded in a delivery sheath, optionally disposable, in its constrained delivery state and coupled with a delivery shaft as shown in
Delivery
A method of use may involve the following delivery steps:
From a CT scan, measurements are taken to confirm intended valve placement location, target airway diameter and length;
An appropriately sized lobar valve is chosen to match the measured airway size.
The lobar valve is visually inspected prior to loading into a delivery sheath;
A bronchoscope is advanced through the patient's endotracheal tube to the targeted lobar airway;
The lobar valve in the delivery sheath is advanced distally through a working channel of the bronchoscope;
The distal end of the delivery system is advanced distally out of the working channel to a desired valve position in the target airway;
Optionally, aligning a radial visual marker on the delivery sheath with an orientation of an oval bronchus.
While holding the bronchoscope in position relative to the airway the delivery sheath is retracted proximally relative to the shaft and lobar valve to deploy the lobar valve to its expanded but coupled position;
The position, fit, alignment, and seal may be visually inspected through the lens of the bronchoscope. The delivery system may be pulled gently to confirm mechanical anchoring or engagement of the valve against the airway wall;
If position, fit, alignment, seal and anchoring are not satisfactory optionally push or pull the delivery system to adjust;
If position, fit, alignment, seal and anchoring are still not satisfactory retract the lobar valve at least partially back into the delivery sheath;
The delivery sheath and lobar valve may be repositioned and redeployed;
If the position, fit, alignment, seal and anchoring are satisfactory the lobar valve may be disengaged from the coupler of the delivery system;
The delivery system may be removed from the patient;
The lobar valve may be visually inspected through the lens of the bronchoscope;
The bronchoscope may be removed from the patient.
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). In addition, 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.
This application claims priority to U.S. Provisional application 62/964,370 filed Jan. 22, 2020, the entirety of which is incorporated by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2021/014581 | 1/22/2021 | WO |
Number | Date | Country | |
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62964370 | Jan 2020 | US |