Catheter

IS 2 140 495 T3

DESCRIPTION

Catheter.

The present invention relates to preformed tubular catheters for transradial percutaneous catheterization applications, which comprise a distal bridge-shaped portion that presents a distal arch that defines a first curve, an upper part that defines a second curve, and a proximal arch that defines a third curve, in which said proximal arch was connected to a distal end of a straight and rigid shaft.

Preformed catheters are commonly used for medical procedures such as diagnostic or coronary angioplasty or intracoronary spring implantation in which they serve to guide other catheters such as catheters for pressure measurement or with balloons or with a surgical spring loaded balloon. In these procedures, a femoral application is normally used in which the preformed catheter is introduced into the aorta through the femoral artery, and the catheter is then manipulated at its proximal end with pushing or pulling and / or twisting movements. , to drive its distal end into the lumen of the selected vessel. To aid the advancement of the catheter through the cardiovascular system, a relatively rigid guidewire is inserted into the catheter to straighten it and bring the tip of the catheter in the direction of the origin of the selected artery prior to actual cannulation. After the catheter is inserted into the artery, the guide wire is removed, and the catheter can be used for a diagnostic procedure or to guide another catheter such as a balloon catheter or a surgical spring loaded balloon catheter.

In order to fulfill its function as a guide, the preformed catheter should have a reserve element or an effective stability in the area where it is placed in order to resist the forces and movements of the pulsating environment as well as the stresses and deformations caused. by the passage of the balloon catheter or other catheter or equipment that is guiding. It should also provide good coaxiality for proper alignment with the artery orifice to avoid loss of thrust force on the guided catheter or risk of trauma caused by a surgical spring loaded balloon catheter misaligned into the tube. Cup. Likewise, the preformed guide catheter should have some adaptability of automatic configuration to easily find its way through the vascular system with a lot of manipulations to reduce, whenever possible, the load of the positioning path on the patient. It should also have an appreciable ability to deal with a variety of elevations or angular positions that the left coronary artery, right coronary artery, or venous bypass implants may have relative to the arch of the aorta. And, when in the selected position, the catheter should lock in place and be able to be pulled out with longitudinal tension by the operator.

Therefore, preformed guide catheters should have a configuration of lones, curves and / or angles that precisely match the context of the environment in which they are to be used and therefore it is practically impossible to simply foresee the effects of changes made. in the form of the catheter.

A large number of preformed catheters have been designed over the years for transfemoral catheterization.

For example, the most commonly used catheter for the left coronary arteries, especially the catheter called the "Left Judkins" which comprises an elongated straight shaft portion followed by a distal end portion consisting of a straight portion extending from the shaft portion and followed by an approximately 180 ° curved portion followed by a straight portion that forms a small angle with the straight portion extending from the shaft portion, ending this last straight portion in a pointed portion substantially perpendicular to it. This catheter was often made of a plastic material and most catheters of this type have a flexibility that is not modulated throughout. They are also supplied in oblique configurations to accommodate deflection requirements. This type of catheter cannot be applied to the right coronary arteries and, therefore, another catheter has been designed for the right coronary arteries, especially the catheter called the “Right Judkins”, also made of plastic material, comprising a portion elongated shaft having the elongated S-shape ending in a pointed portion substantially perpendicular to the distal end of the S-shaped shaft portion. Most catheters of this type also have a flexibility that is not modulated throughout them.

Other preformed catheters made of plastic material have been devised, most of which have a flexibility that is not modulated throughout them, for example the catheters described in WO 92/12754, the object of which is to improve "Judkins" catheters. ”. According to a first embodiment, intended for left coronary arteries, the catheter comprises a first portion with a straight axis followed by a distal end portion that comprises a second straight portion that extends at an angle with the first straight portion, followed by a curved portion. of about 180^° followed by a third straight portion substantially parallel to the second straight portion, and a pointed portion extending from the third straight portion and forming an angle to the east, this pointed portion extending behind the first straight-axis portion; This catheter is suitable for use with a relatively stiff wire inserted into the bone. A second embodiment, also intended for the left coronary arteries and for use with a rigid wire inserted therein, comprises a first portion with an elongated straight axis followed by a distal end portion consisting of a second straight portion that forms angle with the first portion of right angle, a curved portion extending from the se2

ES 2 140 495 T3 second straight portion approximately 180 °, a third straight portion extending from the curved portion at an angle to the second straight portion, and a pointed portion extending at an angle with the third portion straight and parallel to the second straight portion, the pointed portion extending behind the first straight portion. A third mode of implementation, also intended for the left coronary arteries and for use with a rigid guide wire, and more particularly for left coronary arteries that are angularly displaced posteriorly from their normal distance (a situation called posterior deviation), It comprises a first straight portion extending from the proximal end of the catheter and a distal end portion consisting of a second straight portion extending at an angle to the first straight portion and followed by a curved portion extending approximately 180^°, the portion being curved followed by a third portion ending in a pointed portion; In this catheter, the first and third straight portions are bent outward from the plane formed by the second straight portion and the curved portion. A fourth embodiment that is intended for use with a rigid guidewire in a right coronary artery that is angularly displaced from its normal position and has an anterior disassembly, comprises a first straight portion and a distal end portion formed by a second straight portion. extending from the first straight portion forming an angle in the foreground that is between 50^° y70^° and forming an angle in a second plane that is perpendicular to the first plane that is between 20^° y40^°; a third straight-pointed portion that extends from the second straight portion forming an angle that is between 20^° y30^° in the foreground and an angle that is between 40^° y50^° with the second portion straight. A fifth embodiment, intended for use with a rigid guidewire in a venous bypass that connects the aorta with the distal segment of the right coronary artery, comprises a first portion with a straight axis and a distal end portion consisting of a first curved portion that prolongs the first straight portion, a second curved portion that extends the first curved portion in front of it and followed by a straight-tip portion parallel to the first straight portion.

Other preformed catheters are also available on the market such as, for example, the catheter called the "Left Amplatz" or the "Right Amplatz" which is built in variants of a basic shape having a straight elongated shaft followed by a first curve in a first direction followed by a second curve in the opposite direction, or the catheter called the "multipurpose" which is based on a shape having a substantially straight axis portion followed by a curve, most of which has a flexibility that is not modulated throughout.

A percutaneous transradial application of catheterization is currently being investigated due to the favorable anatomical relationships of the radial artery with its surrounding structures and the dual blood supply available. The potential advantages of this application are safe transarterial coronary interventions that combine rapid post-operative patient mobilization with the resulting reduced hospitalization, and easy, safe, and effective hemostasis leading to a reduced incidence of major complications related to the procedure. access to the actuation site.

To date, however, no specific catheters are available for this technique. Typically, catheters such as those mentioned above have been used that are specific to the percutaneous transfemoral catheterization application, however with relative lack of success in relation to the reserve element and the alignment coaxiality with the artery. In addition, they usually require a straightening wire to bring the tip of the catheter in the direction of the orifice of the artery. And a plurality of catheters are needed to accommodate various stripping configurations; and even so, some tricks must be used properly.

US patent N^° 5203776 shows a catheter that can be used for femoral or brachial catheterization. This catheter comprises a shaft, a solidary shaped portion and a solidary pointed portion. The profiled portion extends from the distal end of the shaft to the proximal end of the pointed portion and comprises a first curve, a first substantially straight branch, a second curve, a second substantially straight branch, and a third curve. This construction is made of materials that are selected to provide a catheter that is rigid.

Therefore, it is an object of the present invention to improve the percutaneous transradial application of catheterization by proposing a specific catheter for transradial catheterization. It is a further object of the invention to provide a catheter for transradial application which avoids the drawbacks of catheters for femoral application used for transradial application. A further object of the invention is to provide a catheter for transradial application that is simple to manufacture with available techniques, and that avoids unnecessary expenses as well as complex storage or ordering procedures.

In order to fulfill these and other objects, the invention conforms to the definitions given in the claims.

Therefore, the combination of a flexible first curve with rigid structures provides modulated flexibility and allows selective cannulation of the right coronary arteries, left coronary arteries, and venous bypass implants. It also allows treating a variety of right coronary artery implant diversion, left coronary artery and venous bypass conditions. As this also makes it possible to bring the tip of the catheter in the direction of the origin of the coronary artery, before any cannulation, there is an improved coaxiality of the catheter. Deep intubation through the steep bends of

ES 2 140 495 T3 coronary irregularities. Rigid structures facilitate support in the contralateral sinus of the aorta and additional support against the wall of the aorta; optimize resistance to twisting and kinking during catheter manipulations; they also optimize the support for easier manipulations and changes of angles of the first curve; and once the catheter is positioned they facilitate the total reserve element of the catheter.

As a result, a guidewire is not required to guide the catheter tip in the direction of the coronary origin prior to cannulation. There is smooth passage of the surgical springs due to the reduced friction at the location of the catheter curves. The success of the delivery of the surgical spring is therefore greatly improved and the implantation of the surgical spring can be a common procedure, not only for selective cases, and without the need to change guide catheters.

Another advantage is that the catheter has a multipurpose ability to treat right coronary arteries, left coronary arteries, and venous bypass implants, without the need to change catheters during a multi-vessel procedure, thus avoiding artery spasm and discomfort, potential loss of distal access in extreme tortuosity, a long process and fluoridation time as well as unnecessary costs and heavy storage procedures.

And, of course, the catheter is compatible with percutaneous transluminal coronary angioplasty, perfusion, intracoronary spring delivery, and diagnosis.

The objects, particularities and advantages cited and others of the invention will be deduced from the following detailed description with reference to the accompanying drawings which show, schematically and by way of example only, a preferred but only illustrative embodiment of the invention.

Figures 1 and 2 are side and front views, respectively, of a portion of the catheter according to the invention.

Figures 3, 4 and 5 are, respectively, cross-sectional views of a portion of a cardiovascular system with the catheter inserted into the left coronary artery.

Figure 6 is a cross-sectional view of a portion of a cardiovascular system with the catheter inserted into the right coronary artery.

The catheter represented in Figures 1 and 2 is tubular and comprises a distal bridge-shaped portion 1 that has a distal arch 2 that defines a first curve 3, an upper part 4 that defines a second curve 5 and a proximal arch 6 that defines a third curve 7. The proximal arch 6 is connected to a distal end 8 of a straight shaft 9 whose proximal end is fitted to the usual handling connector (not shown). The shaft 9 is stiff and the bridge-shaped portion 1 has a flexibility that extends at least up to the first bend 3 that it includes, and a stiffness that extends up to at least the third bend 7 that it includes.

Meas specifically, the bridge-shaped portion 1 comprises a first straight distal portion 10, a first curve 3 extending from said first straight portion 10, said first curve having a concavity oriented towards the proximal end 11 of the shaped portion. bridge 1. A second straight portion 12 extends from the first curve 3 and slopes towards the proximal end 11 of the bridge-shaped portion 1. A second curve 5 extending from the second straight portion 12 and said second curve has an oriented concavity between the first distal straight portion 10 and the proximal end 11 of the bridge-shaped portion 1. A third straight portion 13 extends from the second curve 5, that said straight portion 13 is inclined towards the proximal end 11 of the bridge-shaped portion 1. A third curve 7 extends from the third straight portion 13 and said third curve has a concavity facing towards the first distal straight portion 10; a proximal end 14 of said third bend is connected to the distal end 8 of shaft 9.

The shaft 9 is stiff and the flexibility of the bridge-shaped portion 1 extends over the first straight distal portion 10, the first curve 3 and a distal portion 15 of a second straight portion 12 while the proximal portion of the second portion straight 12, second portion 5, third portion straight 13 and third portion 7 are rigid. Rigidity can be obtained, for example, with a coating of braided material 16 embedded in the plastic material that forms the catheter or otherwise, for example, by the quality of the material in the appropriate areas.

Preferably, the second curve extends over about 90 ° and the third curve extends over about 45 °. However, this data can be selected in another way.

In a preferred embodiment, the second straight portion 12 and the third straight portion 13 have essentially the same length. However, it is possible to choose another mode, for example the second and third straight portions may have different lengths.

The first distal straight portion 10 may be, as shown, substantially parallel to the straight axis 9. However, this first distal straight portion 10 may be selected with an angle that opens in the direction of the straight axis 9.

Rather than extending to the distal portion 15 of the second straight portion 12, the flexibility of the bridging portion 1 may extend more near the first curve 3 or proximally beyond the distal portion 15 of the second portion. straight 12.

A soft tip can be attached to the distal end of the first distal straight portion 10 to be totally trauma free.

Figure 3 represents a cardiovascular system 17 in which the left coronary artery 18 has a horizontal deviation. As can be seen, the third curve 7 rests on the wall of the aorta; after pulling the catheter, the second bend

ES 2 140 495 T3 will deflect the first curve so that the first straight portion 10 inserts coaxially into the orifice of the artery.

Figure 4 shows a cardiovascular system 19 in which the left coronary artery 20 has a downward deviation. In this situation, when the catheter was pulled, the support conditions of the second and third curves 5 and 7 were modified to redirect the first curve 3 and the first straight portion 10 in the direction of the artery orifice.

Figure 5 shows a cardiovascular system 21 in which the left coronary artery has a vertical deviation. Under these conditions, the catheter would need to be pushed so that the third curve 7 rests more deeply in the root while the second curve 5 deflects the first curve 3 so that it is in a more vertical position to ensure the coaxiality of the first. straight portion 10 with the passage or orifice of the artery.

Figure 6 shows a cardiovascular system 23 in which the right coronary artery is represented in horizontal deviation 24, and respectively in upward deviation 24 ', and respectively in downward deviation 24 “. As can be seen, the third curve 7 and the second curve 5 facilitate correct targeting of the first curve 3 and the first straight portion 10 in coaxial alignment with the artery. To achieve insertion in the upward deviation 24 ', a push on the axis 9 of the catheter provided an upward deviation of the first curve 3 and the corresponding upward directional movement of the first straight portion 10 to insert coaxially into the artery. The insertion in the descending outlet 24 ”required that the shaft 9 of the catheter be pulled so that the first curve 3 adopts a more descending deviation that would redirect the first straight portion 10 downwards to be properly inserted in the hole or passageway. coaxial.

As can be seen, in all these conditions, the catheter has a strong reserve element due to the support condition of the third curve and / or the second curve, and / or the third straight portion.