IE20120301A1 - A perfusion dilation balloon catheter - Google Patents

Abstract

A perfusion dilation balloon catheter for insertion into a canal of a body in a medical procedure, comprises an elongate flexible tubular member (11) having a proximal end (not shown) and a distal end (13), and an inflatable balloon (14) attached to the distal end (13). The inflatable balloon (14) has an outer wall (15) and an inner wall (16) with a fillable void (17) defined therebetween. The inflatable balloon (14) is movable between a deflated state and an inflated state by the introduction of fluid into the fillable void (17) and vice versa, with the inflatable balloon (14). The fluid is introduced through a lumen (not shown) in the elongate member (11). The walls (15, 16) of the inflatable balloon (14) define a first opening (18) and a second opposed opening (19) therethrough, such that, in the inflated state, a longitudinal passageway (20) is created through the inflatable balloon (14) between the first and second openings (18, 19) to enable passage of a bodily fluid therethrough. The outer wall (15) and the inner wall (16) are bonded together at a plurality of discrete locations (21) such that, in the inflated state, the inner wall (16) is held to the outer wall (15) and is thus prevented from moving towards the centreline of the passageway (20) and thereby occluding it.

Description

A perfusion dilation balloon catheter This invention relates to a perfusion dilation balloon catheter and, in particular, to a catheter for insertion into a canal of a body in a medical procedure.

Dilation balloon catheters are used in cardiological, pulmonary and urological procedures, where a particular canal is blocked by a stenosis, fhe catheter is inserted into the canal and the balloon is manoeuvred into position adjacent the stenosis. Once in position the balloon is inflated in an effort to clear the stenosis.

A dilation balloon catheter can also be used to fix a stent in position, deliver a drug to a particular site within a canal, or locate a sensor at a particular site within a canal.

In typical procedures involving catheters, when the balloon of a catheter device is inflated in a canal all flow ceases in that canal for the period of time the balloon is inflated.

If the balloon is inflated in a canal for a prolonged period of time there is the possibility of complications due to the lack of fluid flow through the canal, which fluid flow would take place under normal bodily functions.

Various solutions have been proposed in order to solve this problem.

«J 2 ΰ 3 ο τ Thus, for example, U.S. Patent No. 5,613,948 describes a catheter suitable for percutaneous transluminal coronary angioplasty procedures and the like. The catheter includes an annular balloon having an exterior wall, an interior wall and an inner longitudinal passageway defined by the interior wall. An elongated flexible tube extends into an interior compartment formed between the exterior and interior walls to pass fluid therebetween and inflate and deflate the balloon between a collapsed condition and an expanded condition. When in its expanded condition, the balloon engages a body vessel wail for dilating the body vessel, while simultaneously pemiitting perfusion of blood thro ugh the longitudinal passageway without need for an additional mechanism for pumping or channelling the blood.

A problem with this design of balloon catheter is that, when the balloon is inflated, the rise in pressure within the interior compartment serves to expand the exterior wall of the balloon with the result that the body vessel is dilated. However, the increased pressure within the interior compartment causes the interior wall to expand into Ute longitudinal passageway resulting in partial occlusion thereof. This partial occlusion will necessarily result in a reduction of fluid flow through the longitudinal passageway, which may result in complications in the vessel downstream of the balloon.

It is an object of the present invention to provide a perfusion dilation balloon catheter which overcomes the disadvantages of the aforementioned systems. ,£ 1 2 Ο 3 0 1 Thus, the invention provides a perfusion dilation balloon catheter for insertion into a canal of a body in a medical procedure, comprising an elongate flexible tubular member having a proximal end and a distal end, an inflatable balloon attached to the distal end, the inflatable balloon having an outer wall and an inner wall with a filiable void defined therebetween, the inflatable balloon being movable between a deflated state and an inflated stale by the introduction of fluid into the fill able void and vice versa, the walls of the inflatable balloon defining a first opening and a second opposed opening therethrough, such that, in the inflated state, a longitudinal passageway is created through the balloon between the first and second openings to enable passage of a bodily fluid therethrough, in use, characterised in that the inflated balloon has a cross-sectional diameter of at least 6mm p and in that the outer wall and the inner wall are bonded together at a plurality of discrete locations such that, in the inflated state, the inner wall is held to the outer wall and is thus prevented from moving towards the centreline of the passageway and thereby occluding it.

An advantage of the catheter in accordance with the invention is that the inflated balloon may remain in the canal for a prolonged period without resulting in complications due to lack of fluid flow in the canal, downstream of the balloon.

Due to the manner in which the outer and inner walls of the balloon are joined together, they will remain in close proximity on inflation of the balloon. Thus, the longitudinal passageway will not be occluded by the inner wall.

IE 1 2 Ο 3 β f The perfusion dilation balloon catheter in accordance with the invention is suitable for inflated balloon cross-sectional diameters from 6 mm upwards. Below 6mm the balloons are not efficient due to the geometrical limitations of the design.

Preferably, the outer and inner walls are bonded together at the plurality of discrete locations by welding, adhesive bonding or other bonding processes.

The bonding process chosen for a particular application will depend on the materials chosen for the balloon walls. l ΰ Further, preferably, the outer and inner walls are bonded together at the plurality of discrete locations by spot welding.

The advantage of this arrangement is that the plurality of discrete locations can be arranged so that outer and inner walls are uniformly separated In the inflated state. This means that the balloon will move from the deflated state to the inflated state witit ease.

In a further embodiment of the invention, the outer and inner walls are bonded together at the plurality of discrete locations by radial, longitudinal, or angular seams, without partitioning the Tillable void.

The advantage of this embodiment is that balloons may be 20 constructed to suit various applications.

IE 1 2 Ο 3 0 1 In a further embodiment of the invention, the bonding of the outer and inner wails at each discrete location results in a plurality of bonded locations, at which a drug or a sensor may be located.

An advantage of this arrangement is that a drug or sensor may be 5 placed at a specific location within the canal and may be embedded into the outer surface of tire balloon. Thus, the inflated balloon will remain in close contact with the canal walis. As the flow of fluid through the canal is not impeded by the inflated balloon it may be left in place for extended periods, allowing the drug to be released in a controlled fashion In a further embodiment of the invention, the outer wall is coated with a drug eluting coating.

An advantage of this feature is that the entire area of the canal wall, which is contacted by the inflated balloon, will be acted on by the drug.

In a further embodiment of the perfusion dilation balloon catheter in accordance with the invention a pull cord is located within the fillable void and extends through the elongate flexible member to emerge at the proximal end thereof, such that, in use, when the pull cord is activated at the proximal end, with the balloon in the deflated state, the profile ofthe balloon is reduced.

An advantage of the pull cord is that the profile of the deflated balloon can be kept to a minimum, which aids in the insertion of the IE1 2 0 3 ο 1 catheter into the canal and its withdrawal therefrom, following the procedure.

Preferably, the material used to construct the balloon inner and outer walls is selected from the group consisting of polyurethane, nylon, polyethylene terephthalate (PET), polyamide and other suitable thermoplastic polymers.

The choice of material will depend on a particular application.

Further, preferably, the inner and outer walls are formed as multilayer membranes, with the outer layer to one side being constructed from a material with good bonding capability, and the outer layer to the other side being constructed from a material having good resistance to pressure burst.

Suitably, the bonding material with good bonding capability is polyurethane and the material having good resistance to pressure burst Is nylon.

The invention will be further illustrated by the following description of an embodiment thereof, given by way of example only with reference to the accompanying drawings in which; Fig. 1 is a perspective view of a perfusion dilation balloon catheter 20 according to the invention; and Fig. 2 is an enlarged view of the area marked “A” in Fig 1. Ί ΙΕ ί 4 ο 3 Ο 1 Referring to Fig. 1, there is illustrated, generally at 10, a perfusion dilation balloon catheter for insertion into a canal of a body in a medical procedure, comprising an elongate flexible tubular member 11 having a proximal end 12 and a distal end 13, and an inflatable balloon 14 attached to the distal end 13. The inflatable balloon 14 has an outer wall 15 and an inner wall 16 with a tillable void 17 (see Fig. 2) defined therebetween.

The inflatable balloon 14 is movable between a deflated state and an inflated state by the introduction of fluid into the fi liable void 17 and vice versa, with the inflatable balloon 14 being illustrated in the inflated state in the figure. The fluid is introduced through the lumen (not shown) in the elongate member 11. The walls 15, 16 of the inflatable balloon 14 define a first opening 18 and a second opposed opening 19 therethrough, such that, in the inflated state, a longitudinal passageway is created through tlie inflatable balloon 14 between the first and second openings 18, 19 to enable passage of a bodily fluid therethrough.

Referring to Fig. 2, the inflatable balloon 14 is illustrated in a partially cutaway state. The inflated balloon 14 has a cross-sectional diameter of at ieast 6 mm.

The outer wall 15 and the inner wall 16 are bonded together at a plurality of discrete locations 21 such that, in the inflated state, the inner wall 16 is held to the outer wall 15 and is thus prevented from moving towards the centreline of the passageway 20 and thereby occluding it. The outer wall 15 and the inner wall 16 are bonded together by spot welding. fff ?6 3ϋ 1 A pull cord 22 is located within the fillable void 17 and extends through the elongate flexible member 11 to emerge at the proximal end 12 thereof (see Fig. 1). When the pull cord 22 is activated at the proximal end 12 (see Fig. 1) with the balloon 14 in the deflated state (not shown), the profile of the balloon 14 is reduced. Thus, the profile of the deflated balloon can be kept lo a minimum, which aids in the insertion of the catheter into the canal and its withdrawal therefrom, following the medical procedure.

Claims (10)

1. A perfusion dilation balloon catheter for insertion into a canal of a body in a medical procedure, comprising an elongate flexible tubular member having a proximal end and a distal end, an inflatable 5 balloon attached to the distal end, the inflatable balloon having an outer wall and an inner wall with a fiJlable void defined therebetween, the inflatable balloon being movable between a deflated state and an inflated state by the introduction of fluid into the Tillable void and vice versa, the walls of the inflatable balloon defining a first opening and a second 10 opposed opening therethrough, sueh that, in the inflated state, a longitudinal passageway is created through the balloon between the first and second openings to enable passage of a bodily fluid therethrough, in use, characterised in that the inflated balloon has a cross-sectional diameter of at least 6mm, and in that the outer wall and the inner wall are 15 bonded together at a plurality of discrete locations such that, in the inflated state, the inner wall is held to the outer wall and is thus prevented from moving towards the centreline of the passageway and thereby occluding it.

2. A perfusion dilation balloon catheter according to Claim 1, 20 wherein the outer and inner walls are bonded together at the plurality of discrete locations by welding, adhesive bonding or other bonding processes.

3. A perfusion dilation balloon catheter according to Claim 1, wherein the outer and inner walls are bonded together at the plurality of 25 discrete locations by spot welding. IEl 2 ο 3 Ο 1 ίο

4. A perfusion dilation balloon catheter according to Claim 1, wherein the outer and inner walls are bonded together al the plurality of discrete locations by radial, longitudinal, or angular seams, without partitioning the fill able void.

5. 5. A perfusion dilation balloon catheter according to any preceding claim, wherein the bonding ofthe outer and inner wails at each discrete location results in a plurality of bonded locations, at which a drug or a sensor may be located.

6. A perfusion dilation balloon catheter according to any 10 preceding claim, wherein the outer wall is coated with a drug eluting coating.

7. A perfusion dilation balloon catheter according to any preceding claim, wherein a pull cord is located within the fi liable void and extends through the elongate flexible member lo emerge at the 15 proximal end thereof, such that, in use, when the pull cord is activated at the proximal end, with the balloon in the deflated stale, the profile of the balloon is reduced.

8. A perfusion dilation balloon catheter according to any preceding claim, wherein the material used to construct the balloon inner 20 and outer walls is selected from the group consisting of polyurethane, nylon, polyethylene terephthalate (PET), polyamide and other suitable thermoplastic polymers. ΙΕΐ 2{?3 {J 1

9. A perfusion dilation balloon catheter according to any preceding claim, wherein the inner and outer walls are formed as multilayer membranes, with the outer layer to one side being constructed from a material with good bonding capability, and the outer layer to the other 5 side being constructed from a material having good resistance to pressure burst.

10. A perfusion dilation balloon catheter according to Claim 9, wherein the bonding material with good bonding capability Is polyurethane and the material having good resistance to pressure burst is 10 nylon.