Method for inhibiting restenosis

Details Method for inhibiting restenosis Method for inhibiting restenosis

1998-11-30

2001-06-05

Kennedy, Sharon (Department: 3763)

Surgery

Means for introducing or removing material from body for...

Treating material introduced into or removed from body...

Reexamination Certificate

active

06241718

ABSTRACT:

CROSS REFERENCE TO RELATED APPLICATIONS
Not Applicable.
STATEMENT REGARDING FEDERALLY FUNDED RESEARCH
Not Applicable.
FIELD OF THE INVENTION
The present invention relates generally to inhibiting restenosis, and more particularly to treating tissue with cryogenic energy to inhibit restenosis.
BACKGROUND OF THE INVENTION
It is well known to perform an angioplasty procedure to open an arterial vessel that is occluded due to arteriosclerosis, for example. Typically, a balloon catheter is inserted into the patient's arterial network and manipulated to the occluded region of the vessel which is generally proximate the heart. The balloon portion of the catheter is inflated so as to compress the arterial plaque against the vessel walls. The luminal area of the vessel is thereby increased which allows more blood to flow through the vessel.
While the angioplasty procedure may initially be successful, a significant percentage of patients experience restenosis of the treated area. That is, the opened region of the vessel gradually recloses in a relatively short amount of time, such as about six months. Although the exact mechanism is not understood, restenosis is generally believed to involve platelet aggregation, thrombus formation, and smooth cell migration and proliferation, either singly or in combination. However it occurs, restenosis ultimately negates the benefits achieved by the angioplasty procedure.
In order to prevent mechanical recoil of the vessel wall where the balloon is inflated, as well as to mitigate the effects of restenosis, a stent may be implanted in the opened region of the vessel after the angioplasty procedure. As known to one of ordinary skill in the art, a typical stent has a generally cylindrical shape to conform to the vessel and can be formed from a wire mesh. However, stents may irritate the vessel wall. Further, in some patients stents are believed to be the cause of rapid tissue growth, or intimal hyperplasia, through openings in the stent walls.
It would, therefore, be desirable to provide a technique to inhibit restenosis of a vessel region treated with a balloon catheter.
SUMMARY OF THE INVENTION
The present invention provides a technique to minimize restenosis of a dilated region of a blood vessel. In one embodiment, a method of inhibiting restenosis in accordance with the present invention includes applying cryogenic energy to a dilated region of a blood vessel for a predetermined amount of time. A variety of cryogenic systems can be used to cool the target tissue. Exemplary systems include cryogenic catheters having a thermally transmissive distal tip with an elongate and/or rounded geometry. The distal tip can be selectively deformable from a linear shape to an arcuate configuration for achieving contact with the desired tissue.
In an exemplary procedure, the cryogenic catheter is inserted into the patient's arterial network and manipulated to a dilated region of the vessel. Alternatively, the cryogenic catheter forms a portion of a percutaneous transluminal coronary angioplasty (PTCA) assembly which includes the use of a balloon catheter. After the balloon is inflated to open the occluded region of the vessel, the cryogenic catheter is energized to cool the treated site to a selected temperature. If a stent is to be placed in the vessel, it is understood that cryotreatment of the dilated vessel region can be done before, during, and/or after implantation of the stent. An exemplary treatment temperature ranges from about zero degrees Celsius to about one hundred and twenty degrees Celsius for a duration in the range from about ten seconds to about sixty minutes. In one embodiment, the catheter cools the tissue to about minus fifty degrees Celsius for about two minutes.


REFERENCES:
patent: 4685458 (1987-08-01), Leckrone
patent: 4709698 (1987-12-01), Johnston et al.
patent: 4748982 (1988-06-01), Horzewski et al.
patent: 4754752 (1988-07-01), Ginsburg et al.
patent: 4771777 (1988-09-01), Horzewski et al.
patent: 4860744 (1989-08-01), Johnson et al.
patent: 4924863 (1990-05-01), Sterzer
patent: 4998933 (1991-03-01), Eggers et al.
patent: 5078713 (1992-01-01), Varney
patent: 5108390 (1992-04-01), Potocky et al.
patent: 5114423 (1992-05-01), Kasprzyk et al.
patent: 5139496 (1992-08-01), Hed
patent: 5147355 (1992-09-01), Friedman et al.
patent: 5275595 (1994-01-01), Dobak, III
patent: 5281215 (1994-01-01), Milder
patent: 5370608 (1994-12-01), Sahota et al.
patent: 5403309 (1995-04-01), Coleman et al.
patent: 5417653 (1995-05-01), Sahota et al.
patent: 5417689 (1995-05-01), Fine
patent: 5419760 (1995-05-01), Narciso, Jr.
patent: 5452582 (1995-09-01), Longsworth
patent: 5531742 (1996-07-01), Barken
patent: 5667505 (1997-09-01), Straus
patent: 5716353 (1998-02-01), Matsuura et al.
patent: 5775338 (1998-07-01), Hastings
patent: 5800486 (1998-09-01), Thome et al.
patent: 5800487 (1998-09-01), Mikus et al.
patent: 5800488 (1998-09-01), Crockett
patent: 5807391 (1998-09-01), Wijkamp
patent: 5833685 (1998-11-01), Tortal et al.
patent: 5860970 (1999-01-01), Goddard et al.
patent: 5868735 (1999-02-01), Lafontaine
patent: 5971979 (1999-10-01), Joye et al.

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