JP7125517B2 - Dilator - Google Patents

Description

TECHNICAL FIELD The present disclosure relates to medical devices for percutaneous endovascular surgery and, more particularly, to methods for transradial catheterization using radial artery access.

More interventional procedures can be performed percutaneously by using one or more catheters to access treatment sites within the patient's vasculature or other regions. Although many procedures are commonly accessed through the femoral artery, some access-related complications are associated with this point of entry. Examples of negative outcomes include severe hemorrhagic complications, retroperitoneal bleeding, increased transfusion requirements, pseudoaneurysms, difficulty in hemostasis after surgery, and the need for prolonged immobilization. , both of which may be relevant for the transfemoral approach. Also, the larger the entry hole in the femoral artery, the more likely the above complications will occur. Correspondingly, it may be desirable to catheterize other vessels to reduce or avoid such complications, or to catheterize the femoral artery with a smaller diameter entry hole.

One preferred method for catheter insertion is through the radial artery located in the patient's wrist. Transradial artery catheterization offers many advantages over the femoral approach, including reduced bleeding complications and faster ambulation. However, there are several problems with catheterization of vessels of this small size. For example, cramping, pain and/or discomfort may occur. Radial artery catheterization can also lead to iatrogenic radial artery occlusion. Radial artery catheterization also limits the overall diameter of the guide catheter that can be used. Generally, procedures are limited to 6 French sizes in most patients, impeding the ability to perform some of the more complex coronary artery surgery, peripheral endovascular surgery and cardiac structural interventional procedures. Important predictors of radial artery spasm during transradial artery catheterization include a small body mass index, a small radial artery, and a large "sheath diameter/radial artery diameter ratio." As will be appreciated, spasm can lead to pain, irritation and inflammation, reducing the success rate of transradial artery catheterization. Similarly, the most important predictors of radial artery occlusion after transradial catheterization include patient gender (because females generally have smaller vessel diameters) and 6 French (or larger) sheath size. includes the use of All of these problems are therefore associated with the relatively small diameter of the radial artery and the corresponding
This is due to the increased potential for stretching, dilation or irritation by inserting a device with an outer diameter greater than the inner diameter of the radial artery.

These problems are exacerbated when sheaths are used in catheterization. Since the guide catheter is delivered through the sheath, the sheath must necessarily have a large outer diameter. The outer diameter of the sheath is on average 0.60 millimeters larger than a correspondingly sized catheter. To handle this situation, it is desirable to use a sheathless system. Conventional approaches may still require a radial sheath and are not true sheathless systems. Currently available sheathless systems are expensive and cost is increased by requiring the use of a new system for each guide catheter exchange. Currently available sheathless systems also require a specific configuration of the guide catheter to be used with the system, limiting the choice of catheter size and shape accordingly and allowing the operator to choose the preferred guide catheter shape or design. Potentially prevent use.

One component of the sheathless system is a dilator, which is inserted through a puncture used to access the vessel to be treated and then advanced through the vasculature along a guidewire. be done. The dilator has a tapered distal tip and is generally used to gradually stretch and widen the vessel to smooth the transition between the diameter of the guidewire and the outer diameter of the guide catheter used for the procedure. can be used. For this reason, the dilator should have sufficient length to access distal locations within the vasculature, as well as sufficient pushability and flexibility to navigate through tortuous anatomy. must have gender.

To facilitate manipulations associated with advancing the dilator through the vasculature, it may be desirable to provide a rapid exchange port on the distal region of the dilator. The rapid exchange port communicates with a guidewire that extends to the distal end of the dilator, allowing dilator exchange without the need to use an extended length of guidewire. Dilator designs that use tubular structures generally require that the rapid exchange ports be formed by milling or an equivalent manufacturing process. These methods are time consuming, labor intensive and therefore costly. again,
The milling of the quick exchange ports creates burrs around the openings that must be carefully removed and creates a large amount of particulate waste that is difficult to completely remove.

Accordingly, the inventors have recognized that there is a need in the art for a dilator that allows for the use of increased diameter guide catheters by eliminating the need to place the guide catheter through a sheath. The inventors have also recognized that it would be desirable to facilitate the formation of rapid exchange ports. Further, the inventor has recognized that it would be desirable to provide a dilator that has good pushability while maintaining sufficient flexibility to navigate through a patient's vasculature. The present disclosure meets these and other needs, as set forth in the following material.

SUMMARY OF THE DISCLOSURE The present disclosure is a dilator for accessing a blood vessel of a patient, comprising a tubular distal member having a maximum outer diameter extending from a distal end to a proximal end having a shaved portion and a distal member having a shaved portion. a proximal member extending from the distal end to the proximal end and a rapid exchange port at the transition region formed by the overlap of the shaved portion of the distal end of the proximal member and the shaved portion of the proximal end of the distal member; and a lumen extending between a rapid exchange port and a distal end of a distal member.

In one aspect, the rapid exchange port can be an opening formed by opposing angles of a shaved portion of the distal member and a shaved portion of the proximal member.

In one aspect, the proximal member can be a hypotube.

In one aspect, the proximal member can have a reduced diameter with respect to the maximum outer diameter of the distal member, wherein the shaved portion of the proximal member extends from the distal member within the projected peripheral surface of the distal member. can overlap coaxially with the shaved off portion of the The shaved portion of the proximal member can extend distally past the shaved portion of the distal member within the lumen.

In one aspect, the dilator can have a transition tube, wherein at least the shaved portion of the proximal member is coaxially disposed within the transition tube, the transition tube overlapping at least the shaved portion of the distal member and the distal member. Coaxially arranged in the projected peripheral plane. If desired, the transition tube can extend distally within the lumen past the shaved portion of the distal member.

In one aspect, the transition tube can be heat welded to at least the shaved portion of the proximal member and at least the shaved portion of the distal member.

In one aspect, the transition tube can be complete from the proximal end to the distal end. Alternatively, the distal end of the transition tube can be shaved to correspond to the shaved portion of the proximal member.

In one aspect, the distal member can be more flexible than the proximal member.

The present disclosure also provides a method of accessing a blood vessel of a patient, comprising: a tubular distal member having a maximum outer diameter extending from a distal end to a proximal end having a shaved portion; and a distal end having a shaved portion. a rapid exchange port at the transition region formed by the overlap of the proximal member extending from the proximal end to the proximal end of the proximal member; providing a dilator having a lumen extending between the exchange port and the distal end of the distal member; positioning a guidewire within the patient's vessel; and allowing the guidewire to exit the rapid exchange port. and advancing a dilator over a guidewire and into the vessel without inserting the dilator through the sheath.

In one aspect, a guide catheter can be advanced over the dilator and the dilator can be removed.

In one aspect, the blood vessel can be the radial artery.

Further features and advantages will become apparent from the following more detailed description of the preferred embodiments of the disclosure illustrated in the accompanying drawings. In the accompanying drawings, like reference numerals generally refer to the same parts or elements.
FIG. 10 is a front view of a dilator having a rapid exchange port for sheathless access of blood vessels according to one embodiment. 2 is a side view of a quick-exchange port of the dilator of FIG. 1 according to one embodiment; FIG. 2 is a top view of a quick-exchange port of the dilator of FIG. 1 according to one embodiment; FIG.

First, it is to be understood that this disclosure is not limited to the materials, structures, routines, methods or compositions specifically illustrated, as such may vary. Accordingly, although many such alternatives similar or equivalent to those described herein can be used in the practice or embodiment of the present disclosure, preferred materials and methods are described herein.

The terminology used herein is intended to describe certain embodiments of the present disclosure,
It should also be understood that no limitation is intended.

DETAILED DESCRIPTION The detailed description set forth below in conjunction with the accompanying drawings is intended as a description of exemplary embodiments of the disclosure and is intended to represent only exemplary embodiments in which the disclosure may be practiced. not intended. The term "exemplary" used throughout this description means "for example,
serves as an example or illustration, and should not necessarily be construed as preferred or advantageous over other exemplary embodiments. The detailed description includes specific details to provide a thorough understanding of the exemplary embodiments herein. It will be apparent to those skilled in the art that the exemplary embodiments herein may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the novelty of the exemplary embodiments presented herein.

For convenience and clarity only, directional terms such as up, down, left, right, up, down, up, up, down, down, back, back, front, etc. may be used with respect to the accompanying drawings. These terms and similar directional terms should not be construed to limit the scope of the disclosure in any way.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

Finally, as used herein and in the appended claims, the singular "a"
"An" and "the" include plural referents unless the content clearly dictates otherwise.

As noted above, transradial artery catheterization offers greater benefits than the femoral approach due to the potential for reduced complications. By using the techniques of the present disclosure, the use of a sheath can be avoided when inserting a guide catheter into a patient's vessel, such as the radial artery. Since no sheath is required, a correspondingly larger diameter guide catheter can be used. The majority of coronary interventions require a 6 French guide catheter. The median diameter of the radial artery ranges from 1.9 mm to 2.5 mm in various ethnic groups.
mm range, but the use of a conventional 2.5 mm access (6 French sheath) is likely to cause the above problems.

Sheaths were originally designed for femoral artery access, but differences in the anatomy and physiology of arteries such as the radial and leg arteries can eliminate the need to use an access sheath. Thus, sheathless access to arteries can be used to perform a given catheterization task, minimizing the required penetration wound, such as up to 2 French sizes. For example, penetration using a guide catheter instead of a sheath can be performed with a smaller overall diameter for each French size (eg, 0.5 mm or less). As a result, this may reduce the amount the artery is stretched and dilated, which in turn may reduce the potential for irritation, inflammation, pain and/or iatrogenic arterial occlusion. As such, these techniques are used to reduce the size of the invasion in any catheterization procedure, including those for transradial, transbrachial, transfemoral and transpedal access and other accesses. be able to.

The technology of the present disclosure, for example, allows transradial artery access while completely eliminating the need to use a sheath, and thus is a true sheath that can be used for diagnostics and all types of coronary interventional and peripheral procedures. It is wireless access. In particular, these techniques work well with smaller sized punctures (holes) for each catheter size required for all patients. Most diagnostic procedures and many interventional procedures can be performed with a 1.67 mm (5 French) guide catheter thanks to sheathless access, and the same access can be performed with a 2.00 mm (6 French) or 2.32 mm (7 French)
can be expanded to larger sizes such as guide catheters. Such increased size also reduces the size of the radial artery access in any procedure, thereby reducing bone artery access limitations such as spasm, pain, injury, radial artery occlusion and the inability to perform complex interventions. To reduce or eliminate the use of a correspondingly larger sheath is avoided. Embodiments of the present disclosure can solve all of the above problems associated with transradial artery catheterization.

To help explain aspects of the present disclosure, an exemplary embodiment of a radial artery access dilator is shown schematically in FIG. 1 in front view. As shown, dilator 10 is an elongated member having a longitudinal axis along line LL and having a tapered distal end 12 that increases to a maximum outer diameter on tubular distal member 14 . The maximum outer diameter can be selected to closely match the inner diameter of the guide catheter used in a given procedure, and can be substantially constant throughout distal member 14 .

Distal member 14 is coupled to proximal member 16 at transition region 18, which also forms quick-exchange port 20, as described in greater detail below. The distal member 14 has a lumen 22 extending from the distal end 12 to the rapid exchange port 20 and has a diameter of, for example, 0.021 inch (0.021 inch).
58 mm) guide wire or a 0.035 inch (0.88 mm) guide wire, although other diameters are used depending on the intended use. can also

Proximal member 16 extends from transition region 18 to the proximal end of dilator 10 and can have an outer diameter that is generally constant and less than the maximum outer diameter of distal member 14 . tapered distal end 1
2 can be approximately 4 cm in length to provide a smooth transition with the outer diameter of the guidewire used to facilitate dilation of the skin, subcutaneous tissue and arterial wall. Optionally, some or all of dilator 10 is hydrophilic to facilitate insertion and advancement through the patient's vasculature and to reduce friction as the guide catheter is advanced along the dilator. can have a coating. In one aspect, tapered distal end 12 and proximal member 14
can have a hydrophilic coating.

As noted above, dilator 10 is desirably characterized by a combination of flexibility, pushability, and sufficient column strength to advance the dilator through the patient's vasculature. Thus, distal member 14 can be formed from a polymeric material with increased flexibility, while proximal member 16 can be formed from a relatively stiff material, such as a polymer or metal. can be. In an exemplary embodiment, distal member 14 is made of nylon (polyamide), urethane, polypropylene, as well as polyether block amide (PE), for example.
The proximal member 1 may be formed from a polyamide copolymer such as BAX®).
6 is stainless steel, shape memory alloys (e.g. Nitinol or other nickel titanium alloys)
Or it can be a hypotube of a relatively stiff polymer such as polyetheretherketone (PEEK). Proximal member 16 can also be a solid rod or wire in some embodiments. In particular, the material (eg, metallic material) used for the proximal member 16 assumes a memorized shape to the proximal member 16 that impedes advancement of the dilator 10 through the patient's vasculature.
It allows the dilator 10 to be stored in a coiled configuration without having to apply pressure.

The relative dimensions of dilator 10 can be selected based on the distance between the access point and the location where treatment is to be performed. As merely a representative example, distal member 14 is approximately 20-30 cm.
, the transition region 18 can be in the range of about 10-15 cm, and the proximal member 16 can be in the range of about 90-120 cm. Therefore, the proximal member 1
The reduced profile of 6 occupies a substantial portion of the length of the dilator 10, has less friction with the inner diameter of the guide catheter, and facilitates advancement of the guide catheter along the dilator 10. The overall length of dilator 10 and the respective length of each member can be adjusted to reach the desired location within the patient's vasculature. Generally, the dilator 10 can extend approximately 10-20 cm from the proximal end of the guide catheter when preloaded for insertion into a blood vessel. In this configuration, the proximal ends of both the guide catheter and dilator can be manipulated during insertion and advancement. As mentioned, the maximum outer diameter of distal member 14 can correspond closely to the inner diameter of the guide catheter used for the procedure. For example, for a 6 French guide catheter,
Including adjustments for other sizes, the maximum outer diameter can be about 1.80 mm.

The transition region 18 extends between the distal member 14 and the proximal member 16, as shown schematically in the side view of FIG. 2 and the top view of FIG. 3, with the longitudinal axis indicated by line LL. A quick exchange port 20 is formed as a result of the partial overlap. These figures are not to scale and are intended to show the overall relationship between the respective members. As shown, material or a layer of such material is removed from tubular distal member 14 at its proximal end, hereinafter referred to as "scraped portion" 24.
, and may form an exposed inner chevron surface 24 having a partial circumference rather than a full canal distal to the trimmed portion 24 . Similarly, material may be removed from the proximal member 16 to form a chevron skived portion 26 . In embodiments where proximal member 16 is tubular, skive portion 26 also has a partial circumference rather than a full tube proximal to skive portion 26 . The angle of the skived portions 24 and 26 is greater than the distal member 14
can be opposed to form a rapid exchange port 20 communicating with a lumen 22 of the.
In one aspect, the reduced diameter of proximal member 16 relative to distal member 14 causes skive portion 26 to coaxially overlap skive portion 24 within the projected circumference of full distal member 14 . Due to the amount of material removed when forming the shaved portions 24 and 26, the opening of the rapid exchange port 20 occupies a substantial portion of the projected circumference of the tubular distal member 14 and is less than or equal to the length of the guidewire. Allows for easy exit. In comparison, a conventional port formed by milling an opening through the surface of the tube takes up less peripheral surface and requires the user to bend or flex the tube to exit the guidewire. Sometimes you have to operate in other ways.

The skived portion 26 of the proximal member 16 overlaps the skived portion 24 of the distal member 14, and they can be secured together in any suitable manner. By way of example, distal member 14 is, in the illustrated embodiment, connected to the proximal member by transition tube 28 such that the distal end of proximal member 16 including skived portion 26 is coaxially disposed within transition tube 28 . 16 is fixed.
The transition tube, on the other hand, extends coaxially within the proximal end of distal member 14 . As shown, the transition tube 28 may overlap a sufficient amount of the distal member 14 such that the transition tube 28 extends distally past the trimmed portion 24 and into the fully formed lumen 22 . can. However, in other embodiments
Transition tube 28 may not extend into the lumen and may only overlap skive portion 24 . Similarly, the distal end of trimming portion 26 can extend past trimming portion 24 as shown, or can terminate before the lumen is complete. transition pipe 28
can be heat welded to secure the distal member 14 and the proximal member 16 to each other where they overlap. In other embodiments, adhesives or mechanical bonding as well as other known techniques can be used as desired. The transition tube 28 can remain intact over the distal end of the proximal member 16 and conform to the skive portion 26 as a result of the heat welding process, or can be skived as well. can. If left intact, the transition tube 28
can facilitate guidewire exit from the rapid exchange port 20 by blocking the entrance to the lumen of the proximal member 16 when using a tubular member. The transition tube 28 can be formed from similar materials (but without metal portions) as described above for the distal and proximal ends. For example, using nylon (polyamide), urethane, polypropylene, and polyamide copolymers such as polyether block amide (PEBAX®), or relatively stiff polymers such as polyetheretherketone (PEEK) and the actual material depends on the intended parameters of the device. Because the transition tube has a larger surface area than the overlapping skive portions 24 and 26, a reliable and secure bond can be formed. The transition tube 28 also provides a gradual change in flexibility between the relatively stiff proximal member 16 and the flexible distal member 14, while reducing the tendency to kink at the junction. do. In comparison, a conventional port formed by milling an opening through the surface of the tube causes a discontinuous transition in flexibility and column strength, reducing the potential for kinking at the port. may increase. again,
Because the transition tube 28 and the shaved portion 26 of the proximal member 16 are coaxially located within the contour of the maximum outer diameter of the distal member 14, the connection is a protrusion that impedes advancement of the dilator 10 through the patient's vasculature. or cause no harm. Note that the material used for proximal member 16 should be less flexible than the material for distal member 14 . One way to ensure that this relationship is maintained during the material selection process is to measure the deflection of the proximal member 16 with a goniometer at a given load, and measure the deflection of the distal member 16 with the goniometer using the same load. is to compare with the deflection of

Any suitable method can be used for use of the dilator 10 for transradial artery catheterization, as well as the use of other sizes of guide catheters and guidewires for access to other vessels of the patient. can be extended to include By way of example, transradial artery access is obtained by palpation or ultrasound guidance as desired. The radial artery can be punctured using a 21 gauge needle or similar device. A pre-puncture or post-puncture can be performed using either a bare needle or a venous access needle within the catheter, respectively. Once pulsatile blood flow is observed, a guidewire is inserted into the radial artery, then the needle is removed while the guidewire is anchored in the radial artery lumen to achieve hemostasis. The dilator 10 may be preloaded with an appropriate guide catheter, which may be selected in view of the procedure to be performed, and both may be advanced over the guidewire into the radial artery. After advancing a corresponding distance, the guidewire exits the rapid exchange port 20 . The relatively smooth, atraumatic transition between the largest outer diameter section 14 and the outer diameter of the guide catheter, due to the close fit between the outer diameter of the dilator and the inner diameter of the guide catheter, helps guide along the dilator. Facilitate advancement of the catheter. Once the guide catheter has been properly advanced so that its distal end is adjacent the junction between the tapered distal end 12 and the maximum outer diameter distal member 14, the dilator can be removed.

As can be appreciated from the above description, access to the radial artery using dilator 10 requires at least 0.5 mm smaller hole and less penetration into the radial artery as compared to conventional entry using a sheath. can be achieved. For example, a 6 French sheath has 2.61 in the radial artery.
mm puncture, while the radial artery access dilator 10 can be used to reduce the maximum diameter of the radial artery puncture and the device inserted into the artery to approximately 2.00 mm.
Thus, most or all patients can tolerate the use of a 6 French guide catheter with significantly less trauma. Also, a 7 French guide catheter (2.3 mm outer diameter) can be used in more patients so that more complex coronary and peripheral procedures can be performed. In other procedures, a 5 French guide catheter can be used. Compared to sheath access, regardless of guide catheter size,
The need for a smaller hole and avoidance/reduction of dilation and/or irritation of the radial artery may reduce spasm, pain,
It reduces or eliminates inflammation and obstruction, allowing successful transradial artery catheterization. By using a relatively stiff proximal member 16, the dilator 10 exhibits improved control and pushability as it is advanced within the patient's vasculature. The relatively flexible distal member 14 also improves navigation through tortuous anatomy and reduces trauma. Securing distal member 14 to proximal member 16 at transition region 18 as described facilitates formation of rapid-exchange port 20 while maintaining column strength and providing kink resistance.

The foregoing description is presented with reference to the presently disclosed embodiments of the invention. Those skilled in the art and technology to which the present invention pertains will appreciate that changes and modifications to the structures described may be practiced without departing from the principle, spirit and scope of the present invention. As will be appreciated by those skilled in the art, the drawings are not necessarily to scale. Therefore, the foregoing description should not be read as relating only to the precise structures described and illustrated in the accompanying drawings, but rather should be construed as following claims having their fullest and fairest scope. and should be read in support of the following claims.

Claims (11)

A dilator for accessing a patient's blood vessel, comprising:
a tubular distal member extending along a longitudinal axis, the distal member having a maximum outer diameter from a distal end to a proximal end and a shaved portion;
a proximal member longitudinally extending from a distal end to a proximal end having a shaved portion;
a transition tube connected to the proximal member such that the proximal member is coaxially disposed within the transition tube, the transition tube connecting to the distal member at an overlapping portion extending coaxially within the proximal end of the distal member; a connected transition pipe;
a quick-exchange port at a transition region formed by an overlap of a shaved portion of the proximal member distal end and a shaved portion of the distal member proximal end;
a lumen extending longitudinally continuously through the rapid exchange port between the proximal end of the distal member and the distal end of the proximal member. The dilator of claim 1, wherein the quick-exchange port includes an opening formed by opposing angles of a shaved portion of the distal member and a shaved portion of the proximal member. The dilator of Claim 1, wherein the proximal member comprises a hypotube. The proximal member has a reduced diameter with respect to the maximum outer diameter of the distal member, and the shaved portion of the proximal member is the distal diameter within the projected peripheral surface of the distal member. 2. The dilator of claim 1, coaxially overlying the shaved portion of the member. 5. The dilator of claim 4, wherein the shaved portion of the proximal member extends distally within the lumen past the shaved portion of the distal member. At least the skive portion of the proximal member is coaxially disposed within the transition tube, the transition tube overlapping at least the skive portion of the distal member and coaxial within the projected peripheral surface of the distal member. 5. The dilator of claim 4, positioned in the . 7. The dilator of claim 6, wherein the transition tube extends distally within the lumen past a shaved portion of the distal member. 7. The dilator of claim 6, wherein the transition tube is heat welded to at least a shave portion of the proximal member and at least a shave portion of the distal member. 7. The dilator of claim 6, wherein the transition tube is integral from proximal end to distal end. 7. The dilator of Claim 6, wherein the distal end of the transition tube is shaved to correspond to the shaved portion of the proximal member. The dilator of Claim 1, wherein the distal member is more flexible than the proximal member.

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