NEUROMODULATION CRYOTHERAPEUTIC DEVICES AND ASSOCIATED SYSTEMS AND METHODS

1 . A cryotherapeutic device, comprising:

a shaft including a proximal portion and a distal portion, wherein the distal portion includes a recess inward relative to the proximal portion;

an exhaust lumen along at least a portion of the shaft;

a supply lumen along at least a portion of the shaft; and

a cooling assembly including an expandable member attached proximate the recess of the distal portion and an expansion chamber in fluid communication with the supply lumen and the exhaust lumen, the expansion chamber being defined by at least a portion of the expandable member and having a delivery state and a deployed state, wherein at least a portion of the expandable member is in the recess of the distal portion of the shaft when the expansion chamber is in the delivery state.

2 . The cryotherapeutic device of claim 1 wherein the expandable member further includes a connector configured to attach the expandable member proximate the recess.

3 . The cryotherapeutic device of claim 2 wherein the expandable member is a balloon, and wherein the connector is defined by a proximal portion of the balloon.

4 . The cryotherapeutic device of claim 2 wherein:

the distal portion of the shaft includes a first zone, a second zone distal to the first zone, and a step that defines the inward recess and demarcates the first zone from the second zone; and

the connector is at least partially over the step and the first zone, the connector having a substantially similar outer diameter in the deployed state as in the delivery state.

5 . The cryotherapeutic device of claim 2 wherein:

the distal portion of the shaft includes a first zone, a second zone distal to the first zone, and a step that defines the inward recess and demarcates the first zone from the second zone; and

at least a portion of the connector is in the recess proximate the step.

6 . The cryotherapeutic device of claim 1 wherein:

the expandable member includes a distal end portion; and

the cryotherapeutic device further comprises an atraumatic tip extending from the distal end portion of the expandable member.

7 . A cryotherapeutic device, comprising:

a shaft including a distal portion configured to be located in a renal vessel, the distal portion of the shaft including a first zone having a first outer dimension and a second zone having a second outer dimension less than the first outer dimension, wherein the second zone is distal to the first zone;

an exhaust lumen along at least a portion of the shaft; and

a cooling assembly at the distal portion of the shaft, wherein the cooling assembly includes an expandable member over the second zone of the distal portion, the expandable member having an expansion chamber configured to receive expanded refrigerant and in fluid communication with the exhaust lumen.

8 . The cryotherapeutic device of claim 7 wherein:

the distal portion of the shaft includes a step demarcating the first zone from the second zone; and

the expandable member includes a connector over the second zone adjacent the step, the expandable member extending distally from the connector.

9 . The cryotherapeutic device of claim 7 wherein:

the distal portion of the shaft includes a step demarcating the first zone from the second zone; and

the expandable member includes a connector over at least a portion of the first zone, the expandable member extending distally from the connector.

10 . The cryotherapeutic device of claim 7 wherein:

the first zone of the distal portion has a first outer surface;

the distal portion further comprises a step demarcating the first zone from the second zone;

the expandable member includes a connector over the second zone of the distal portion;

the expansion chamber has a delivery state having a first volume and an deployed state having a second volume larger than the first volume; and

the connector of the expandable member is at least proximate the step and substantially flush with the first outer surface of the first zone when the expansion chamber is in the delivery state.

11 . The cryotherapeutic device of claim 7 wherein:

the distal portion of the shaft further comprises a step demarcating the first zone from the second zone;

the expansion chamber has a delivery state having a first volume and an deployed state having a second volume larger than the first volume; and

the expandable member includes a connector having a substantially constant outer diameter in the deployed state and the delivery state.

12 . The cryotherapeutic device of claim 11 wherein the connector is over the step.

13 . The cryotherapeutic device of claim 7 wherein:

the exhaust lumen at the first zone has a first inner diameter; and

the exhaust lumen at the second zone has a second inner diameter less than the first diameter.

14 . The cryotherapeutic device of claim 7 wherein:

at least a portion of the expansion chamber has a therapeutic temperature; and

the exhaust lumen at the second zone of the distal portion has a volume configured to at least substantially maintain the therapeutic temperature of the expansion chamber when the refrigerant exhausts through the exhaust lumen at the second zone.

15 . The cryotherapeutic device of claim 14 wherein the second zone of the distal portion of the shaft has a length of no more than approximately 4 cm.

16 . The cryotherapeutic device of claim 7 wherein the expansion chamber comprises a balloon having a connector, and wherein the connector is attached over the second zone of the distal portion.

17 . The cyotherapeutic device of claim 7 wherein:

the expandable member comprises a connector over the second zone, the connector having a thickness;

the first zone of the distal portion has a first outer diameter; and

the second zone of the distal portion of the shaft has a second outer diameter equal to not more than the first diameter less twice the thickness of the connection portion.

18 . The cryotherapeutic device of claim 7 wherein the distal portion of the shaft includes a rabbet demarcating the first zone from the second zone.

19 . A method of treating a patient, the method comprising:

intravascularly positioning a cooling assembly at least proximate a peripheral vessel, wherein the cooling assembly includes an expandable member having a connector over a distal portion of a shaft and an expansion chamber defined by at least a portion of the expandable member, wherein the distal portion of the shaft has a first cross-sectional outer dimension at a first zone and a second cross-sectional outer dimension less than the first cross-sectional dimension at a second zone, and wherein the connector of the expandable member is proximate a boundary between the first and second zones of the distal portion;

expanding a refrigerant in the expansion chamber; and

cryomodulating at least a portion of neural fibers of the peripheral vessel proximate the cooling assembly.

20 . The method of claim 19 wherein the peripheral vessel is a first peripheral vessel, wherein the expansion chamber has a delivery state and a deployed state, and wherein the method further comprises:

terminating cryomodulation of the neural fibers in the first peripheral vessel and collapsing the expansion chamber to the delivery state, the expandable member having a connector over the second zone, wherein the connector is substantially flush with the first cross-sectional outer dimension of the first zone when the expansion chamber is in the delivery state;

removing the cooling assembly from the first peripheral vessel;

delivering a contrast material from the proximal portion of the shaft around the distal portion of the shaft and the expandable member;

fluoroscopically locating a second peripheral vessel;

intravascularly positioning the cooling assembly at least proximate the second peripheral vessel;

expanding the refrigerant in the expansion chamber; and

cryomodulating at least a portion of neural fibers of the second peripheral vessel proximate the cooling assembly.

21 . A method of treating a patient, the method comprising:

locating a cooling assembly at least proximate a renal artery or a renal ostium, wherein the cooling assembly includes an expandable member having a connector proximate an inward step at a distal portion of a shaft, wherein the distal portion has a first zone proximal to the inward step and a second zone distal to the inward step;

expanding a refrigerant in at least a portion of the expandable member;

passing the refrigerant through an exhaust inlet at the second zone of the distal portion; and

applying therapeutic cooling with the cooling assembly to renal nerves that innervate a kidney.

22 . The method of claim 21 wherein locating the cooling assembly comprises deploying the expandable member from a sheath.

23 . The method of claim 22 , wherein after applying therapeutic cooling, the method further comprises:

retracting the cooling assembly into the sheath;

re-locating the cooling assembly at least proximate a renal artery or a renal ostium of another kidney while flowing a contrast agent along the shaft; and

repeating the expanding, passing and applying procedures.

24 . A cryotherapeutic device, comprising:

a shaft including a distal portion, wherein the shaft is configured to fit within a 6 Fr guide sheath; and

a cooling assembly at the distal portion of the shaft, the cooling assembly having a length between approximately 8 cm and approximately 15 cm and an expandable member having a delivery state and an expanded state, wherein the expandable member has an outer diameter between approximately 3 mm and approximately 10 mm in the expanded state.

25 . The cryotherapeutic device of claim 24 wherein the distal portion of the shaft includes a first zone having a first outer diameter and a second zone having a second outer diameter less than the first outer diameter.

26 . The cryotherapeutic device of claim 25 , further comprising a step demarcating the first zone from the second zone.

27 . The cryotherapeutic device of claim 26 wherein the expandable member includes a connector proximate the step between the first and second zones.

28 . The cryotherapeutic device of claim 24 wherein:

at least a portion of the expandable member has a therapeutic temperature; and

the cryotherapeutic device further comprises an exhaust lumen along at least a portion of the shaft, the exhaust lumen having a first inner diameter at the first zone and a second inner diameter less than the first inner diameter at the second zone, wherein the exhaust lumen is configured to at least substantially maintain the therapeutic temperature of the expandable member when a refrigerant exhausts through the exhaust lumen at the second zone.

29 . The cryotherapeutic device of claim 24 wherein the shaft has a 4 Fr shaft size.

30 . The cryotherapeutic device of claim 24 wherein expandable member includes at least one balloon, and wherein the balloon has a length of at most 10 cm and an outer diameter of at most 8 mm in an expanded state.

31 . A method using a cryo-device, the method comprising:

deploying a cooling assembly from a 6 Fr sheath, wherein the cooling assembly includes an expandable member having a connector proximate an inward step at a distal portion of a shaft, wherein the distal portion has a first zone proximal to the inward step and a second zone distal to the inward step;

expanding a refrigerant in at least a portion of the expandable member; and

passing the refrigerant through an exhaust inlet at the second zone of the distal portion.

32 . The method of claim 31 , further comprising:

terminating expanding the refrigerant in the expandable member;

retracting the cooling assembly into the 6 Fr sheath;

flowing a contrast material along the sheath; and

repeating the deploying, expanding and passing procedures.