Methods and systems for treating ischemia

• US 6,481,439 B1
• Filed: 08/20/1999
• Issued: 11/19/2002
• Est. Priority Date: 02/03/1998
• Status: Expired due to Fees

• Current Assignee: Salient Interventional Systems Incorporated
• Original Assignee: Salient Interventional Systems Incorporated
• Inventors: Bolduc, Lee R., Lewis, Brian Douglas
• Primary Examiner(s): Isabella, David J.
• Assistant Examiner(s): Chattopadhyay, Urmi
• Application Number:
  US09/377,788
• Time in Patent Office: 1,187 Days
• Field of Search: 128/898, 604/4, 604/7, 604/8, 604/48, 604/500, 604/50, 604/51, 604/52, 604/53, 604/96, 604/102
• US Class Current: 128/898
• CPC Class Codes: A61B 17/22 Implements for squeezing-off ulcers or the like on the inside of inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; Calculus removers; Calculus smashing apparatus; Apparatus for removing obstructions in blood vessels, not otherwise provided for dilators A61M29/00
• CPC Class Codes: A61B 2017/00022 Sensing or detecting at the treatment site
• CPC Class Codes: A61B 2017/22038 with a guide wire
• CPC Class Codes: A61B 2017/22051 with an inflatable part, e.g. balloon, for positioning, blocking, or immobilisation A61B2017/22048, A61B2017/3486 take precedence
• CPC Class Codes: A61B 2017/22077 with a part piercing the tissue A61B2017/22044 takes precedence
• CPC Class Codes: A61B 2017/22082 after introduction of a substance
• CPC Class Codes: A61B 2017/22084 stone- or thrombus-dissolving
• CPC Class Codes: A61M 2025/0002 with a pressure sensor at the distal end
• CPC Class Codes: A61M 2025/0004 having two or more concentrically arranged tubes for forming a concentric catheter system
• CPC Class Codes: A61M 2025/0035 characterized by a variable lumen cross-section by means of a resilient flexible septum or outer wall
• CPC Class Codes: A61M 2025/0037 characterized by lumina being arranged side-by-side
• CPC Class Codes: A61M 2025/0039 characterized by lumina being arranged coaxially
• CPC Class Codes: A61M 2025/0079 Separate user-activated means, e.g. guidewires, guide tubes, balloon catheters or sheaths, for sealing off an orifice, e.g. a lumen or side holes, of a catheter
• CPC Class Codes: A61M 2025/1004 Balloons with folds, e.g. folded or multifolded
• CPC Class Codes: A61M 2025/1079 having radio-opaque markers in the region of the balloon
• CPC Class Codes: A61M 2025/1095 with perfusion means for enabling blood circulation while the balloon is in an inflated state or in a deflated state, e.g. permanent by-pass within catheter shaft
• CPC Class Codes: A61M 2202/0208 Oxygen
• CPC Class Codes: A61M 2210/0693 Brain, cerebrum
• CPC Class Codes: A61M 25/0023 by the form of the lumen, e.g. cross-section, variable diameter
• CPC Class Codes: A61M 25/0029 characterized by features relating to least one lumen located at the middle part of the catheter, e.g. slots, flaps, valves, cuffs, apertures, notches, grooves or rapid exchange ports catheter shaft surface irregularities A61M2025/006
• CPC Class Codes: A61M 25/003 : characterized by features relating to least one lumen located at the distal part of the catheter, e.g. filters, plugs or valves catheter tips A61M25/0067
• CPC Class Codes: A61M 25/0032 : characterized by at least one unconventionally shaped lumen, e.g. polygons, ellipsoids, wedges or shapes comprising concave and convex parts
• CPC Class Codes: A61M 25/0068 : Static characteristics of the catheter tip, e.g. shape, atraumatic tip, curved tip or tip structure
• CPC Class Codes: A61M 25/007 : Side holes, e.g. their profiles or arrangements; Provisions to keep side holes unblocked
• CPC Class Codes: A61M 25/0108 : using radio-opaque or ultrasound markers
• CPC Class Codes: A61M 25/104 : used for angioplasty

Abstract

Methods for treating total and partial occlusions employ a perfusion conduit which is penetrated through the occlusive material. Oxygenated blood or other medium is then perfused through the conduit in a controlled manner, preferably at a controlled pressure below the arterial pressure, to maintain oxygenation and relieve ischemia in tissue distal to the occlusion. In another aspect, interventional devices, such as stents or balloon catheters, are passed through the perfusion catheter to remove obstructions. Optionally, the occlusion may be treated while perfusion is maintained, typically by introducing a thrombolytic or other agent into the occlusive material using the perfusion conduit or by employing mechanical means to remove the obstruction. Such methods are particularly suitable for treating acute stroke to prevent damage to the cerebral tissue.

Claims

1. A method of delivering an oxygenated medium to an ischemic vascular region, comprising the steps of:

providing a catheter having a lumen;

coupling the lumen of the catheter to a source of an oxygenated medium;

advancing the catheter through a patient'"'"'s vasculature to a narrowed region of a blood vessel, wherein an ischemic bed is located downstream from the narrowed region;

passing a distal end of the catheter through the narrowed region of the blood vessel; and

infusing the oxygenated medium into the ischemic bed through the lumen of the catheter, the oxygenated medium being infused at a pressure below arterial pressure at a location upstream of the narrowed region, the infusing step being carried out for a period of time.

2. The method of claim 1, wherein:

the infusing step is carried out by increasing pressure over the period of time.

3. The method of claim 2, wherein:

the infusing step is carried out with by increasing the pressure linearly.

4. The method of claim 2, wherein:

the infusing step is carried out by increasing the pressure non-linearly.

5. The method of claim 1, wherein:

the infusing step is carried out for at least 2 hours.

6. The method of claim 1, wherein:

the infusing step is carried out for at least 4 hours.

7. The method of claim 1, wherein:

the infusing step is carried out for at least 48 hours.

8. The method of claim 1, wherein:

the infusing step is carried out for at least 30 minutes.

9. The method of claim 1, wherein:

the infusing step is carried out for 2-3 days.

10. The method of claim 1, wherein:

the infusing step is initially carried out at a start pressure of below 200 mmHg.

11. The method of claim 1, wherein:

the infusing step is initially carried out at a start pressure of below 150 mmHg.

12. The method of claim 1, wherein:

the infusing step is initially carried out at a start pressure of below 100 mmHg.

13. The method of claim 1, wherein:

the infusing steps is initially carried out at a start pressure of 10 mmHg to 70 mmHg.

14. The method of claim 1, wherein:

the infusing step is carried out by selecting a flow rate which is less than 30 cc/min.

15. The method of claim 1, wherein:

the infusing step is carried out by selecting a flow rate which is less than 10 cc/min.

16. The method of claim 1, further comprising the step of:

measuring pressure with the lumen in the catheter; and

changing the flow rate during the infusing step as a result of the pressure measured during the measuring step.

17. The method of claim 1, wherein:

the providing step is carried out with the lumen having cross-sectional size of 0.77 to 7.1 mm squared along a distal portion of the lumen, the distal portion having a length of at least 5 cm, the proximal portion of the lumen having a larger cross-sectional size than the distal portion of the lumen.

18. The method of claim 1, wherein:

the providing step is carried out with the lumen having cross-sectional size of 1.7 to 2.9 mm squared along the distal portion.

19. The method of claim 18, wherein:

the providing step is carried out with the distal portion having a length of at least 10 cm.

20. The method of claim 18, wherein:

the providing step is carried out with the distal portion having a length of at least 15 cm.

21. A method of delivering an oxygenated medium to an ischemic vascular region, comprising the steps of:

providing a catheter having a lumen;

coupling the lumen of the catheter to a source of an oxygenated medium;

advancing the catheter through a patient'"'"'s vasculature to a narrowed region of a blood vessel, wherein an ischemic bed is located downstream from the narrowed region;

passing a distal end of the catheter through the narrowed region of the blood vessel; and

infusing the oxygenated medium into the ischemic bed through the lumen of the catheter, the oxygenated medium being increasing to a target pressure over a period of time.

22. The method of claim 21, wherein:

the infusing step is carried out with the period of time being one minute.

23. The method of claim 21, wherein:

the infusing step is carried out with the period of time being 30 minutes to 9 hours.

24. The method of claim 21, wherein:

the infusing step is initially carried out at a start pressure of below 200 mmHg.

25. The method of claim 21, wherein:

the infusing step is initially carried out at a start pressure of below 150 mmHg.

26. The method of claim 21, wherein:

the infusing step is initially carried out at a start pressure of below 100 mmHg.

27. The method of claim 21, wherein:

the infusing steps is initially carried out at a start pressure of 10 mmHg to 70 mmHg.

28. The method of claim 21, wherein:

the infusing step is carried out by selecting a flow rate which is less than 30 cc/min.

29. The method of claim 21, wherein:

the infusing step is carried out by selecting a flow rate which is less than 10 cc/min.

30. The method of claim 21, further comprising the step of:

measuring pressure with the lumen in the catheter; and

changing the flow rate during the infusing step as a result of the pressure measured during the measuring step.

31. The method of claim 21, wherein:

the providing step is carried out with the lumen having cross-sectional size of 0.77 to 7.1 mm squared along a distal portion of the lumen, the distal portion having a length of at least 5 cm, the proximal portion of the lumen having a larger cross-sectional size than the distal portion of the lumen.

32. The method of claim 31, wherein:

the providing step is carried out with the lumen having cross-sectional size of 1.7 to 2.9 mm squared along the distal portion.

33. The method of claim 31, wherein:

the providing step is carried out with the distal portion having a length of at least 10 cm.

34. The method of claim 31, wherein:

the providing step is carried out with the distal portion having a length of at least 15 cm.