Methods, systems and devices for reducing the luminal surface area of the gastrointestinal tract

1. A system for treating gastrointestinal tissue in the duodenum of a patient, the system comprising:

an elongate shaft with a distal portion; and

a tissue treatment element positioned on the distal portion of the elongate shaft, wherein the tissue treatment element is constructed and arranged to deliver energy to ablate mucosal tissue of one or more axial segments of the duodenum;

wherein the tissue treatment element comprises one or more fluid delivery elements constructed and arranged to deliver at least 1 ml of fluid to submucosal tissue of each of the one or more axial segments to reduce the inner diameter of each axial segment;

wherein the tissue treatment element comprises an expandable balloon constructed and arranged to expand to a diameter between 19 mm and 27.5 mm and to subsequently ablate the mucosal tissue of each axial segment that has received the at least 1 ml of fluid.

2. The system according to claim 1 , wherein the tissue treatment element is configured to deliver energy to between 2 and 50 axial segments of mucosal tissue.

3. The system according to claim 1 , wherein the system is constructed and arranged to treat a cumulative length of mucosal tissue of the duodenum that is less than 15 cm.

4. The system according to claim 1 , wherein the tissue treatment element is constructed and arranged to cause a reduction in a duodenal tissue characteristic selected from the group consisting of: average height of mucosal folds; surface area of mucosal folds; number of mucosal folds; and combinations thereof.

5. The system according to claim 1 , wherein the tissue treatment element is constructed and arranged to reduce the surface area of the ablated axial segment of mucosal tissue by at least 5%.

6. The system according to claim 1 , wherein the system is configured to reduce at least one of absorption or secretion of the ablated axial segment of mucosal tissue.

7. The system according to claim 1 , wherein the system is constructed and arranged to treat diabetes.

8. The system according to claim 1 , wherein the expandable balloon is constructed and arranged to receive a hot fluid from an energy delivery unit at a temperature selected to ablate the mucosal tissue of each axial segment.

9. The system according to claim 8 , further comprising the energy delivery unit, wherein the energy delivery unit is constructed and arranged to deliver the hot fluid at a temperature at or above 60° C.

10. The system according to claim 1 , wherein the expandable balloon is constructed and arranged to receive a recirculating fluid.

11. The system according to claim 1 , further comprising a controller constructed and arranged to control or monitor a system parameter.

12. The system according to claim 11 , wherein the controlled or monitored system parameter comprises the diameter of the expandable balloon.

13. A system for treating gastrointestinal tissue in the duodenum of a patient, the system comprising:

an elongate shaft with a distal portion;

a tissue treatment element positioned on the distal portion of the elongate shaft, wherein the tissue treatment element comprises an expandable balloon constructed and arranged to receive an ablative fluid that delivers energy to ablate an axial segment of mucosal tissue of the duodenum; and

a console configured to recirculate the ablative fluid in the expandable balloon at a flow rate of at least 50 ml/min;

wherein the console is further constructed and arranged to expand the expandable balloon to a diameter between 19 mm and 27.5 mm prior to recirculating the ablative fluid.

14. The system according to claim 13 , wherein the balloon is constructed and arranged to ablate multiple axial segments of mucosal tissue.

15. The system according to claim 14 , wherein the multiple axial segments comprise between 2 and 50 axial segments of mucosal tissue.

16. The system according to claim 14 , wherein the cumulative length of multiple axial segments of mucosal tissue ablated comprises a length of less than 15 cm.

17. The system according to claim 13 , wherein the tissue treatment element is constructed and arranged to cause a reduction in a duodenal tissue characteristic selected from the group consisting of average height of mucosal folds; surface area of mucosal folds; number of mucosal folds; and combinations thereof.

18. The system according to claim 13 , wherein the tissue treatment element is constructed and arranged to reduce the surface area of the ablated axial segment of mucosal tissue by at least 5%.

19. The system according to claim 13 , wherein the system is configured to reduce at least one of absorption or secretion of the ablated axial segment of mucosal tissue.

20. The system according to claim 13 , wherein the system is constructed and arranged to treat diabetes.

21. The system according to claim 13 , wherein the ablative fluid comprises fluid at an elevated temperature.

22. The system according to claim 21 , wherein the elevated temperature comprises a temperature at or above 60° C.

23. The system according to claim 13 , further comprising a controller constructed and arranged to at least one of control or monitor a system parameter.

24. The system according to claim 23 , wherein the controlled or monitored system parameter comprises the ablative fluid flow rate.

25. A system for treating gastrointestinal tissue in the duodenum of a patient, the system comprising:

an elongate shaft with a distal portion; and

a tissue treatment element positioned on the distal portion of the elongate shaft, wherein the tissue treatment element comprises an expandable balloon constructed and arranged to deliver energy to ablate an axial segment of mucosal tissue of the duodenum;

wherein the expandable balloon is constructed and arranged to expand to a diameter between 19-mm and 27.5 mm; and

wherein the expandable balloon comprises a length of less than or equal to 30 mm.

26. The system according to claim 25 , wherein the balloon is constructed and arranged to deliver energy to multiple axial segments of mucosal tissue.

27. The system according to claim 26 , wherein the multiple axial segments comprise between 2 and 50 axial segments of mucosal tissue.

28. The system according to claim 26 , wherein the cumulative length of multiple axial segments of mucosal tissue receiving energy comprises a length of less than 15 cm.

29. The system according to claim 25 , wherein the tissue treatment element is constructed and arranged to cause a reduction in a duodenal tissue characteristic selected from the group consisting of average height of mucosal folds; surface area of mucosal folds; number of mucosal folds; and combinations thereof.

30. The system according to claim 25 , wherein the tissue treatment element is constructed and arranged to reduce the surface area of the ablated axial segment of mucosal tissue by at least 5%.

31. The system according to claim 25 , wherein the system is configured to reduce at least one of absorption or secretion of the ablated axial segment of mucosal tissue.

32. The system according to claim 25 , wherein the system is constructed and arranged to treat diabetes.

33. The system according to claim 25 , wherein the expandable balloon is constructed and arranged to receive a hot fluid from an energy delivery unit at a temperature selected to ablate the mucosal tissue.

34. The system according to claim 33 , further comprising the energy delivery unit, wherein the energy delivery unit is constructed and arranged to deliver the hot fluid at a temperature at or above 60° C.

35. The system according to claim 25 , wherein the expandable balloon is constructed and arranged to receive a recirculating fluid that delivers energy to the mucosal tissue.

36. The system according to claim 25 , wherein the expandable balloon comprises a length of at least 10 mm.