Surgery – Means for introducing or removing material from body for... – Treating material introduced into or removed from body...
Reexamination Certificate
1997-10-29
2001-01-09
Weiss, John G. (Department: 3763)
Surgery
Means for introducing or removing material from body for...
Treating material introduced into or removed from body...
C604S103090, C606S192000, C600S433000
Reexamination Certificate
active
06171279
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a dilatation catheter of the type known as “over the wire” for introduction into a body canal such as for example a blood vessel.
The invention is principally applicable to the treatment of disorders of the coronary arteries but it can also be used for treating disorders of other body canals, for example the oesophagus or the urethra.
BACKGROUND OF THE INVENTION
Such disorders are generally provoked by the presence, on the inner walls of the canal, of deposits causing strictures or stenoses in said canal.
The treatment of such disorders generally calls for the use of a dilatation catheter for restoring the normal flowing section of the canal at the level of the stenosis by compression with the aid of a balloon.
A guide, normally produced in the form of a wire is used for helping the catheter to reach the stenosis.
The guide-wire is generally longer than the catheter, typically by about 20 to 50 cm, in order to urge the catheter forward into the body canal, by sliding it along the wire.
For correctly positioning the balloon at the level of the stenosis, it is necessary to bring the distal end of the catheter to beyond said stenosis.
Understandably, for the catheter to pass through the stenosis, it is generally necessary to apply a thrusting pressure on the latter.
Said thrusting pressure is exerted by the practitioner at the level of the proximal end of the catheter.
Transmission of said thrusting pressure to the distal end of the catheter raises a problem which, heretofore, has not been solved satisfactorily.
SUMMARY OF THE INVENTION
In the circumstances, it is the object of the present invention to solve the technical problem consisting in providing a new design of dilatation catheter called “over the wire” which can be readily produced on an industrial scale, which is easy to use, and which enables an efficient transmission to the distal part comprising the balloon, of the thrusting pressure exerted at the level of the proximal part.
The solution provided by the present invention for solving said technical problem consists in an over-the-wire dilatation catheter of the type comprising:
a flexible tubular body comprising a distal part, an intermediate part and a proximal part, and having:
a radially deformable portion forming a balloon, disposed at the level of its distal part;
a first inner duct fluidly connected at one end to the interior of the balloon, in liquidtight manner, and connected at the other end to a fluid supply source in order to enable inflating and deflating of the balloon;
a second inner duct, which does not communicate with said first inner duct and traverses longitudinally the body, said duct being defined by a substantially tubular wall and adapted to allow the passage of a guide-wire, characterized in that said catheter further comprises a core having a high modulus of elasticity and being permanently joined to the body by its proximal end and of which the distal end is embedded in the wall defining said second inner duct at the level of its intermediate part.
The novelty of the present invention therefore resides in the use of an element intended for rigidifying the body of the catheter, and for ensuring a reliable and safe transmission of the thrusting pressure exerted at the level of the proximal part of the catheter up to the level of its distal part.
According to an advantageous characteristic, the body comprises in its proximal part a two-channel tube constituted of the eccentric proximal portion of the second inner duct and of a substantially semi-spherical channel forming the proximal part of the first inner duct inside which the free proximal section of said core is contained.
According to another characteristic, the body comprises, in the transitional zone between its proximal part and its intermediate part, a three-channel tube, constituted of a first upper channel, extending, from on the one hand, the semi-cylindrical channel of the proximal part, and on the other hand, connecting to the intermediate portion of the first inner duct, of a second lower channel communicating on each side of the transitional zone with, respectively, the proximal and intermediate portions of the second inner duct, and of a third channel inside which the corresponding section of the metallic core is confined.
According to yet another characteristic, the body comprises, in its intermediate part, an outer tube that extends from the radially deformable balloon-forming portion of the distal part and that surrounds coaxially the intermediate part of the second inner duct while providing an annular space which forms the intermediate part of the first inner duct.
Preferably, the outer tube is fixed at its proximal end to the three-channel tube and to the two-channel tube.
As the core is embedded in the wall of said second inner duct, there is no noticeable reduction of the flowing section of the fluid used for inflating the balloon. Such configuration therefore does not in any way reduce the balloon inflating and deflating time.
According to a particular characteristic, said core has a cross-section which is decreasing from its proximal end towards its distal end.
The gradual decrease of the cross-section of the core therefore confers to the catheter assembly a progressive flexibility under bending and prevents all risks of breaking or kinking thereof.
The resulting catheter shows relatively high rigidity in its proximal part, and a certain amount of flexibility in its distal part, the passage from the rigid part to the more flexible part being done without any breaking.
In other words, the catheter according to the present invention comprises a sufficiently rigid body to allow a good transmission towards the distal part, of the thrusting pressure exerted on the proximal part while ensuring sufficient flexibility at the level of said distal part to enable easy maneuverability of the catheter particularly in the bent portions of the body canal.
The terms “with high modulus of elasticity” as used within the present description and claims, are meant to cover any materials having a modulus of elasticity of at least 10000 MPa.
Advantageously, said core is produced in a metallic material, preferably steel.
According to another characteristic of the invention, said core extends in the intermediate part up to a point situated upstream and in the immediate vicinity of the balloon-forming portion.
Such particular configuration prevents all risks of the balloon being perforated by said core while making sure that the thrusting pressure is transmitted up to the stenosis.
REFERENCES:
patent: 5176637 (1993-01-01), Sagae
patent: 5320605 (1994-06-01), Sahota
patent: 5425711 (1995-06-01), Ressemann et al.
patent: 5490837 (1996-02-01), Blaeser et al.
patent: 5520647 (1996-05-01), Solar
patent: 5531690 (1996-07-01), Solar
patent: 5542926 (1996-08-01), Crocker
patent: 5545134 (1996-08-01), Hilaire et al.
patent: 5545138 (1996-08-01), Fugoso et al.
patent: 5549552 (1996-08-01), Peters et al.
patent: 5607394 (1997-03-01), Andersen et al.
Hilaire Pierre
Salbert Philippe
CathNet-Science S.A.
Leary James J.
Thanh Loan H.
Titus Carol D.
Weiss John G.
LandOfFree
Over-the-wire dilatation catheter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Over-the-wire dilatation catheter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Over-the-wire dilatation catheter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2458653