All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.
Endovascular catheters are effective for treating many types of vascular disease, including by performing percutaneously transluminal angioplasty, or “PTA,” on a lesion obstructing blood flow in a vessel. Such a catheter may be introduced into a patient's vasculature and navigated via a guidewire to a treatment site. However, in some cases, the guidewire may encounter a stenosis completely blocking the vessel, which is known as a chronic total occlusion, or “CTO.”
In such a situation, the success of the procedure often depends on the ability to insert the guidewire through the chronic total occlusion. This may involve the use of a secondary device, such as a so-called “crossing” catheter, to establish guidewire access, such as by tunneling through the lesion using a cutter. Once such access is established, a different catheter is then used to perform a technique to treat the lesion, such as for example via PTA. The use of separate devices to cross the CTO and then treat the lesion complicates the procedure by requiring accessing the vasculature multiple times, and also increases the associated time and expense.
Accordingly, a need is identified for a single catheter than can perform the dual functions of both crossing a lesion, such as a CTO, and then performing percutaneous transluminal angioplasty or atherectomy on it. The device will be robust enough so that once it is used for such procedures, it may continue to be used on any other lesions that may need treatment.
According to one aspect of the disclosure, there is provided an apparatus for crossing a lesion in a vessel and performing percutaneous transluminal angioplasty on the lesion. The apparatus comprises a shaft including a guidewire lumen, an inflation lumen, and a tapered tip adapted for being pushed into the lesion. An inflatable balloon is mounted on the shaft and in communication with the inflation lumen, the inflatable balloon having a proximal portion, a barrel portion having a working surface for compacting the lesion, and a distal tapered portion. Together with the tapered tip, the distal tapered portion of the balloon provides a distal end portion of the shaft with a substantially continuous transition.
In one embodiment, at least a portion of the shaft proximal of the inflatable balloon is braided. A taper of the distal tapered portion of the inflatable balloon and the tapered tip create a continuous sloping transition from a proximal end of the distal tapered portion to a distal end of the tapered tip. This may be achieved by providing both the distal tapered portion and the tapered tip with a taper angle of less than about 20 degrees, such as for example 8-12 degrees, or about 10 degrees. The tapered tip may be elongated and extend to an end having a circular cross-section adapted for receiving and surrounding a guidewire. One or more scoring wires may optionally extend alongside the inflatable balloon. The shaft may include one or more radiopaque markers for identifying a working surface of the inflatable balloon when inflated. The inflatable balloon may be non-compliant, such as by including a layer of inelastic fibers, but may also be formed of elastic fibers, or as a composite balloon without fibers to provide a desired degree of compliance.
A further aspect of the disclosure relates to an apparatus for crossing a lesion in a vessel and performing percutaneous transluminal angioplasty on the lesion. The apparatus includes a shaft with a guidewire lumen, an inflation lumen, and a tapered tip having an end for being advanced into the lesion. An inflatable balloon is mounted on the shaft. More specifically, the inflatable balloon is attached to and forms a continuous sloping transition to the end of the tapered tip.
In one embodiment, the shaft is braided proximally of the inflatable balloon. The inflatable balloon may include a proximal tapered portion and a distal tapered portion. A taper of the distal tapered portion and the tapered tip together form the continuous sloping transition. The distal tapered portion and the tapered tip both have a taper angle of less than about 20 degrees. The inflatable balloon may be non-compliant.
In accordance with a further aspect of the disclosure, a balloon catheter for crossing a lesion in a vessel and performing percutaneous transluminal angioplasty on the lesion is provided. The balloon catheter comprises a shaft including at least a braided portion. The shaft includes a guidewire lumen, an inflation lumen, and a tapered tip adapted for being pushed into the lesion, the tip having a taper from a proximal end portion to a distal end thereof. An inflatable balloon is supported by the shaft and includes a distal tapered portion connected adjacent to the proximal end portion of the tip.
In one embodiment, the distal tapered portion has a first taper corresponding to a second taper of the tapered tip so as to provide the catheter with a substantially uniform taper along a distal end portion thereof. The tapered tip may be elongated, and may comprise a unitary part of the shaft. The inflatable balloon may be non-compliant, and the braided portion of the shaft may be proximal of the inflatable balloon.
This disclosure also relates to a method of crossing a lesion in a vessel and performing percutaneous transluminal angioplasty on the lesion. The method includes the steps of advancing a catheter including a tip having a continuous taper with a distal end portion of a balloon supported by a shaft of the catheter into the lesion, and compacting the lesion using the balloon. The advancing step may comprise advancing a guidewire passing through the shaft of the catheter into the lesion. The advancing step may further comprise successively inflating and deflating the inflated balloon.
The above and further advantages of the disclosure may be better understood by referring to the following description in conjunction with the accompanying drawings in which:
The dimensions of some of the elements may be exaggerated relative to other elements for clarity or several physical components may be included in one functional block or element. Further, sometimes reference numerals may be repeated among the drawings to indicate corresponding or analogous elements. Moreover, some of the items depicted in the drawings may be combined into a single function.
The present disclosure provides a single catheter than may be used to both cross a lesion, such as a CTO, and also perform percutaneous transluminal angioplasty. The device will be sufficiently robust so that once it is used for such procedures, it may continue to be used on any other lesions that may need treatment in a single intervention.
In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the present disclosure. The disclosed embodiments may be practiced without these specific details. In other instances, well-known methods, procedures, components, or structures may not have been described in detail so as not to obscure the aspects of the present disclosure.
The present disclosure is directed to systems and methods for treatment of a vessel. The principles and operation of systems and methods of the disclosure may be better understood with reference to the drawings and accompanying descriptions.
The invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings.
The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
Certain features of the invention that are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.
Referring now to
The balloon 14 may be formed so as to be non-compliant, meaning it does not substantially increase in diameter once fully inflated as a result of increased fluid pressure being applied thereto. To achieve this condition, the balloon 14 may include inelastic fibers 14a, as shown in
The distal end of the catheter 10 includes a tip 22, which may be positioned distal of the distal tapered portion 18 of the balloon 14. The tip 22 may be elongated (e.g., having a length of greater than about 1 centimeter and a considerably smaller transverse dimension). As perhaps best understood from
From
As can be further appreciated, this continuously sloping transition feature provides the catheter 10 with a gradual, but substantially continuously increasing diameter from the point P at the distal end of the tip 22 to at least the distal end of the barrel portion 20, when viewed in the proximal direction. This tapering is generally smooth and substantially uninterrupted, except possibly where a neck 18a at the distal tapered portion 18 of the balloon 14 overlaps with and is attached to shaft 12 or tapered tip 22 (as shown in
The taper angle of the distal tapered portion 18 of the balloon 14 and the tip 22 relative to the longitudinal axis X may be shallow, such as less than about 20 degrees. For example, the taper angle may be about 1-20 degrees or less, such as for example anywhere between about 10 to about 20 degrees (the value of the taper angle in the illustrated embodiment is, for example, about 8-12 degrees, or about 10 degrees). In any case, the taper angle of the distal tapered portion 18 may be less than the taper angle of the proximal tapered portion 16 of the balloon 14, which is typically 20-30 degrees or more.
As can be appreciated, this means that the distal tapered portion 18 is elongated (that is, longer than it is wide), and thus extends along a greater portion of the shaft 12 than the proximal tapered portion 16 (such as 2-3 times more). While the angles of the tapered tip 22 and the distal tapered portion 18 of the balloon 14 substantially match, this provides the distal tapered portion 18 of the catheter 10 with a substantially uniform taper. As can be understood from
With reference to
The shaft 12 may have one of a variety of cross-sectional configurations. For example, as shown in
Alternatively, as shown in
Optionally, the catheter 10 may include one or more external scoring wires 33 extending alongside the balloon 14 for use in scoring or cutting the lesion on expansion. In such case, the shaft 12 may include additional lumen(s) 38 in the shaft 12 for receiving the proximal portions of these scoring wires, as shown in
Turning to
In a typical CTO situation, the guidewire 30 alone may be unable to fully penetrate the lesion L to gain access to a distal end thereof. In such case, the tapered tip 22 of the catheter 10 may be advanced along the guidewire 30 and into the lesion L to help create a path for advance, as shown in
The advance may continue, as shown in
Ultimately, the barrel portion 20 of the balloon 14 may become positioned fully within the lesion L. When expanded to the maximum diameter, if not already done, the balloon 14 compacts the lesion L, thus recanalizing and clearing the vessel V of the obstruction (and may also serve to slice or score the lesion when one or more cutters, such as scoring wire(s) 33, are optionally provided). The balloon 14 may also optionally carry a treatment agent, such as a drug, for application to the compacted lesion L.
Once the PTA procedure is completed, the balloon 14 may then be deflated, and optionally refolded. With aid of guidewire 30, the catheter 10 may then be guided to another location in the vessel V or vasculature for crossing a lesion or performing PTA, with the balloon 14 design again being sufficiently robust to again withstand reinflation and lesion compaction. Additionally, or alternatively, the catheter 10 may simply be withdrawn from the vessel V once the crossing and compaction of a single lesion is completed.
The catheter 10 may of course be provided in a variety of diameters depending on the use to which it may be put in the vasculature. To facilitate use in the vasculature below-the-knee (BTK), the catheter 10 may be made so as to have a small size. For example, the catheter 10 may be 5 French (approximately 5.24 mm in circumference, or 1.667 mm in outer diameter). Other sizes may be used depending on the application.
Summarizing, this disclosure may be considered to relate to the following items:
As used herein, the following terms have the following meanings:
“A”, “an”, and “the” as used herein refers to both singular and plural referents unless the context clearly dictates otherwise. By way of example, “a compartment” refers to one or more than one compartment.
“About,” “substantially,” or “approximately,” as used herein referring to a measurable value, such as a parameter, an amount, a temporal duration, and the like, is meant to encompass variations of +/−20% or less, preferably +/−10% or less, more preferably +/−5% or less, even more preferably +/−1% or less, and still more preferably +/−0.1% or less of and from the specified value, in so far such variations are appropriate to perform in the disclosed invention. However, it is to be understood that the value to which the modifier “about” refers is itself also specifically disclosed.
“Comprise”, “comprising”, and “comprises” and “comprised of” as used herein are synonymous with “include”, “including”, “includes” or “contain”, “containing”, “contains”, and are inclusive or open-ended terms that specifies the presence of what follows e.g. component and do not exclude or preclude the presence of additional, non-recited components, features, element, members, steps, known in the art or disclosed therein.
Although the invention has been described in conjunction with specific embodiments, many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it embraces all such alternatives, modifications, and variations that fall within the appended claims' spirit and scope. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present disclosure.
Filing Document | Filing Date | Country | Kind |
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PCT/US2020/048699 | 8/31/2020 | WO |