Compact delivery pulmonary treatment systems and methods for improving pulmonary function
A pulmonary treatment system includes a compact configuration for delivery to a first airway of a patient. An energy delivery system of the pulmonary treatment system delivers energy to target tissue in or along an airway wall of the first airway to reduce airway resistance in a second airway distal to the first airway. The pulmonary treatment system protects tissue in the airway wall of the first airway located between the target tissue and the energy delivery system by at least one of thermodynamically cooling, circulating a liquid coolant through the pulmonary treatment system, and shielding a portion of the energy delivery system.
1 . A pulmonary treatment system, comprising:
a nerve modification assembly configured to assume a reduced profile for passage through a lumen of an elongate device and positioning in an airway of a patient, the lumen having a diameter less than about 6.0 millimeters, and configured to assume a treatment configuration for treatment of the airway, the nerve modification assembly including:
an energy delivery portion configured to generate heat energy in an airway wall of the airway to ablate nerve tissue along the airway, and
a cooling portion configured to remove heat energy from the airway wall while heat energy is generated in the airway wall by the energy delivery portion, wherein the cooling portion includes an inflatable member and a fluid delivery conduit that extends at least partially around a circumference of the inflatable member when the nerve modification assembly is in the treatment configuration,
wherein the energy delivery member includes an elongate electrode coupled to a portion of the fluid delivery conduit, the electrode being arcuate and flexible, the electrode including:
a tissue facing side, the tissue facing side being convex and electrically conductive,
an inflatable member facing side joined to the tissue facing side, and
an electrically insulating mask adhered to, partially covering, and confined to the tissue facing side, the electrically insulating mask being convex and flexible, the electrically insulating mask thereby defining at least one electrically conductive tissue contact region along the tissue facing side, and at least one electrically insulating tissue contact region bound within the tissue facing side of the energy delivery member.
2 . The pulmonary treatment system of claim 1 , wherein the electrode is configured to deliver radio frequency energy to the airway wall.
3 . The pulmonary treatment system of claim 1 , wherein the cooling portion includes a thermodynamic cooling mechanism.
4 . The pulmonary treatment system of claim 1 , wherein the inflatable member and the fluid delivery conduit are in fluid communication with a source of chilled fluid.
5 . The pulmonary treatment system of claim 1 , wherein the energy delivery portion is configured to generate heat energy at a power density ranging from 0.3 to 1.0 W/mm 2 in an airway wall of the airway.
6 . The pulmonary treatment system of claim 5 , wherein the electrode comprises a collapsible and expandable electrode coupled to a portion of the fluid delivery conduit.
7 . The pulmonary treatment system of claim 1 , the cooling portion is configured to remove heat energy at a power density ranging from about 0.025 to about 1.0 W/mm 2 from the airway wall while heat energy is generated in the airway wall by the energy delivery portion.
8 . The pulmonary treatment system of claim 1 , wherein the energy delivery portion is configured to heat nerve tissue at a depth of at least 2 mm in the airway wall to a temperature of at least 50° C.
9 . The pulmonary treatment system of claim 1 , wherein the cooling portion is configured to cool airway wall tissue disposed between the energy delivery portion and the nerve tissue to a temperature of less than 50° C.
10 . The pulmonary treatment system of claim 1 , wherein
the electrically insulating mask is a first electrically insulating mask,
a second electrically insulating mask is also adhered to, partially covering, and confined to the tissue facing side, and
the at least one electrically conductive tissue contact region extends along the longitudinal axis of the conduit and is bounded between the first electrically insulating mask and the second electrically insulating mask.
11 . The pulmonary treatment system of claim 1 , further comprising:
an elongated shaft having proximal and distal ends and a fluid delivery lumen,
wherein the cooling portion is coupled to the elongate shaft near the distal end and is fluidly coupled to the fluid delivery lumen such that a coolant may be circulated through the cooling portion so as to remove heat energy from the airway wall while heat energy is generated in the airway wall by the energy delivery portion.
12 . The pulmonary treatment system of claim 1 , wherein the fluid delivery conduit is formed of a non-deformable, collapsible material that does not plastically deform at a first pressure.
13 . The pulmonary treatment system of claim 12 , wherein the inflatable member is formed of a compliant material that plastically deforms at a second pressure that is lower than the first pressure.