Methods and systems for treating ischemia

• US 6,436,087 B1
• Filed: 08/20/1999
• Issued: 08/20/2002
• 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): Kennedy, Sharon
• Assistant Examiner(s): RODRIGUEZ, CRIS LOIREN
• Application Number:
  US09/378,089
• Time in Patent Office: 1,096 Days
• Field of Search: 604/523, 604/28, 604/500, 604/507, 604/508, 604/264, 604/7, 604/8, 604/4.01, 604/6.14, 604/48, 128/898
• US Class Current: 604/508
• 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 for perfusing an oxygenated medium at a vascular site, comprising the steps of:

providing a catheter having a shaft and a lumen, the shaft having a proximal end, a distal end, a proximal portion and a distal portion, the distal portion extending for a length of at least 5 cm from the distal end and the proximal portion extending for a length of at least 75 cm , the lumen extending through the shaft and having a cross-sectional area of 0.45 to 2.3 mm² along the distal portion and a cross-sectional area of 2.0-7.6 mm ² along the proximal portion;

advancing the catheter through the patient to a vascular site, the advancing step being carried out with the catheter advanced into the cerebral vasculature;

perfusing an oxygenated medium through the catheter after the advancing step.

2. The method of claim 1, wherein:

the advancing step is carried out with the catheter passing through an obstruction at the vascular site.

3. The method of claim 2, further comprising the step of:

monitoring pressure at a location proximal to the obstruction.

4. The method of claim 2, further comprising the step of:

delivering a therapeutic agent to the obstruction through the catheter.

6. The method of claim 1, wherein the oxygenated medium is blood obtained from the patient.

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

controlling the rate or pressure of the oxygenated medium being perfused to maintain pressure of the oxygenated medium at a control point.

8. The method of claims 7, wherein the control point is in the range from 50 mmHg to 300 mmHg.

10. The method of claim 1, wherein:

the providing step is carried out with the catheter having no more than two lumens.

11. The method of claim 1, wherein:

the providing step is carried out with the catheter having only one fluid lumen.

12. The method of claim 1, wherein:

the providing step is carried out with the catheter having only one lumen.

13. The method of claim 1 wherein:

the providing step is carried out with the catheter having no balloons.

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

cooling the oxygenated medium prior to the perfusing step.

9. The method of claim 9, wherein the control point is increased over time.