Dilator with Containment Features for Sheath Tip - Patent application

Abstract

Described herein are dilators and introducers that include an encapsulation feature configured to couple to an access sheath. For example, the dilator can include an elongate shaft configured to be received within the access sheath. The elongate shaft can be tapered toward a distal end of the elongate shaft. The dilator can also include an encapsulation feature disposed on a distal portion of the elongate shaft. The encapsulation feature can include a number of longitudinally extending tabs. The tabs can be configured to cover a distal end of the access sheath when the elongate shaft is disposed within the access sheath.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to U.S. Provisional Patent Application No. 63 / 314,961, filed February 28, 2022, and entitled "DILATOR WITH ENCAPSULATION FEATURE FOR SHEATH TIPS," the complete disclosure of which is incorporated herein by reference in its entirety. Description of Related Art

[0002] The present disclosure relates generally to the field of medical devices. [Background technology]

[0003] Catheters and other therapeutic devices are often used to deliver medical devices, such as prosthetic heart valves, shunts, stents, or other devices, to locations within the body that are not easily accessible by surgery or where access without invasive surgery is desirable. An access sheath can often be used to introduce the therapeutic device to a desired anatomical structure, such as the patient's vasculature. In some instances, the tip or another portion of the access sheath includes a relatively weak structure that can allow the sheath to expand to accommodate the therapeutic device. Summary of the Invention [Means for solving the problem]

[0004] In embodiments, the present disclosure relates to a dilator comprising an elongate shaft configured to be received within an access sheath and an encapsulation feature disposed on a distal portion of the elongate shaft. The elongate shaft is tapered toward a distal end of the elongate shaft. Additionally, the encapsulation feature includes a plurality of tabs extending toward a proximal end of the elongate shaft. The plurality of tabs are configured to cover the distal end of the access sheath when the elongate shaft is disposed within the access sheath.

[0005] In some cases, the elongate shaft includes a recess configured to receive the plurality of tabs in the collapsed state. The recess includes an outer diameter that is smaller than an outer diameter of a portion of the elongate shaft adjacent the distal portion.

[0006] In some cases, the multiple tabs are configured to be folded onto the elongate shaft to implement the folded state.

[0007] In some examples, the encapsulating feature includes a shape memory alloy. Further, in some examples, the encapsulating feature includes a coupling feature configured to couple the encapsulating feature to the elongate shaft. Further, in some examples, the encapsulating feature is integral with the elongate shaft.

[0008] In some cases, the elongate shaft includes a tapered portion between the distal end of the elongate shaft and the encapsulation feature, the tapered portion tapering toward the distal end of the elongate shaft.

[0009] In some cases, the dilator further comprises a hub coupled to the proximal end of the elongate shaft and configured to selectively engage the access sheath to hold the access sheath in place between the hub and the encapsulation feature.

[0010] In embodiments, the present disclosure relates to a medical system comprising an access sheath including a lumen, a distal end, and a proximal end, and a dilator configured to be received within the lumen. The dilator includes an elongate shaft and an encapsulation feature disposed on a distal portion of the elongate shaft. The encapsulation feature includes a plurality of longitudinally extending tabs. The dilator is configured to implement a encapsulated state in which the plurality of tabs are coupled to the distal end of the access sheath, and a folded state in which the plurality of tabs are radially folded on the elongate shaft.

[0011] In some cases, the elongate shaft includes a recess configured to receive the plurality of tabs in the collapsed state. The recess includes an outer diameter that is smaller than a portion of the elongate shaft adjacent the distal portion.

[0012] In some instances, the encapsulating feature comprises a shape memory alloy. Further, in some instances, the encapsulating feature is integral with the elongate shaft.

[0013] In some instances, the elongate shaft tapers between the encapsulation feature and the distal end of the elongate shaft.

[0014] In some cases, the medical system further comprises a hub coupled to the proximal end of the elongate shaft and configured to hold the access sheath in place between the hub and the encapsulation feature when the dilator is disposed within the access sheath.

[0015] In an embodiment, the present disclosure relates to a method of accessing an anatomical feature, the method including attaching a containment feature of a dilator to a distal end of an access sheath, the containment feature including a plurality of tabs configured to cover the distal end of the access sheath, the method further including advancing the access sheath into the anatomical structure with the dilator attached, translating the dilator distally to remove the containment feature from the access sheath, and translating the dilator proximally to remove the dilator from the access sheath.

[0016] In some cases, the method further includes attaching a hub of the dilator to the proximal end of the access sheath to retain the access sheath between the hub and the containment feature. Advancement of the access sheath occurs with the hub attached to the proximal end of the access sheath.

[0017] In some cases, the expander includes a recessed portion configured to receive the multiple tabs.

[0018] In some cases, distal translation of the dilator causes the tabs to collapse into the recesses.

[0019] In some cases, attaching the encapsulation feature of the dilator to the distal end of the access sheath includes translating the dilator distally through the access sheath, radially expanding the multiple tabs, translating the dilator proximally, and folding the multiple tabs over the distal end of the access sheath.

[0020] In some examples, the encapsulating feature includes a shape memory alloy.

[0021] For purposes of summarizing the disclosure, certain aspects, advantages, and novel features have been described herein. It should be understood that not all such advantages may necessarily be achieved in accordance with any particular embodiment. Thus, the disclosed embodiments may be implemented in a manner that achieves or optimizes one advantage or a group of advantages as taught herein, without necessarily achieving other advantages that may be taught or suggested herein.

[0022] Various embodiments are shown in the accompanying drawings for illustrative purposes and should not be construed as limiting the scope of the disclosed subject matter in any way. In addition, various features of different disclosed embodiments may be combined to form additional embodiments that are part of the present disclosure. Throughout the drawings, reference numbers may be reused to indicate correspondence between referenced elements. However, it should be understood that the use of similar reference numbers in relation to multiple drawings does not necessarily imply similarity between the respective examples associated therewith. Furthermore, it should be understood that features in each drawing are not necessarily drawn to scale and that illustrated sizes are presented for the purpose of illustrating aspects of the invention. In general, some of the illustrated features may be relatively smaller / larger than shown in some embodiments / configurations. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 illustrates an exemplary dilator / introducer that includes an encapsulation feature, according to one or more embodiments. [Diagram 2]FIG. 2 shows exemplary details of the dilator / introducer from FIG. 1, according to one or more embodiments. [Figure 3-1] FIG. 1 illustrates a perspective view of an exemplary encapsulation feature / component implemented with multiple tabs, according to one or more embodiments. [Figure 3-2] FIG. 3-2 shows a side view of the encapsulation feature of FIG. 3-1. [Figure 4] FIG. 4 shows an example of an access sheath that may be implemented with one or more of the introducers / dilators discussed herein, according to one or more embodiments. [Diagram 5] FIG. 5 shows an example configuration of the access sheath from FIG. 4 coupled to a dilator including a tab-based containment feature, according to one or more embodiments. [Figure 6] FIG. 6 shows an example configuration of the access sheath from FIG. 4 coupled to a dilator that includes a stretchable / non-tab based containment feature, according to one or more embodiments. [Figure 7-1] 1 shows an example containment feature having tabs configured in an open / expanded / loaded state according to one or more embodiments. [Figure 7-2] 1 illustrates an example containment feature having tabs configured in a closed / folded state over at least a portion of an access sheath, according to one or more embodiments. [Figure 7-3] 1 illustrates an exemplary containment feature having tabs configured in a closed / folded state on an elongate shaft of an expander, according to one or more embodiments. [Figure 8-1] 1 illustrates an example flow diagram of a process for advancing an access sheath into an anatomical structure using a dilator that includes an encapsulation feature, according to one or more embodiments. [Figure 8-2] 1 illustrates an example flow diagram of a process for advancing an access sheath into an anatomical structure using a dilator that includes an encapsulation feature, according to one or more embodiments. [Figure 8-3] 1 illustrates an example flow diagram of a process for advancing an access sheath into an anatomical structure using a dilator that includes an encapsulation feature, according to one or more embodiments. [Figure 9-1]8-1 depict several images of example anatomical structures and devices associated with the process of FIG. 8-1, illustrating aspects of the process according to one or more implementations thereof. [Figure 9-2] 8-2 depict several images of example anatomical structures and devices associated with the process of FIG. 8-2, illustrating aspects of the process according to one or more implementations thereof. [Figure 9-3] 8-3 depict several images of example anatomical structures and devices associated with the process of FIG. 8-3, illustrating aspects of the process according to one or more implementations thereof. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The headings provided herein are for convenience only and do not necessarily affect the scope or meaning of the claims.

[0025] Although certain preferred examples are disclosed below, the subject matter of the invention extends beyond the specifically disclosed examples to other alternative examples and / or applications, as well as modifications and equivalents thereof. Thus, the scope of claims that may arise from this specification is not limited by any of the specific examples described below. For example, in any method or process disclosed herein, the acts or operations of the method or process may be performed in any suitable order and are not necessarily limited to any particular disclosed order. Although various operations may be described sequentially as multiple separate operations in a manner that may be useful for understanding a particular example, the order of description should not be construed as implying that these operations are order dependent. In addition, the structures, systems, and / or devices described herein may be embodied as integrated components or as separate components. For purposes of comparing various examples, certain aspects and advantages of these examples are described. Not all such aspects or advantages are necessarily achieved by any particular example. Thus, for example, the various examples may be implemented in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other aspects or advantages that may also be taught or suggested herein.

[0026] Certain standard anatomical terms of location are used herein to refer to animal, i.e., human, anatomical structures for the preferred example. While certain spatially relative terms such as "outer", "inner", "superior", "lower", "down", "upper", "vertical", "horizontal", "top", "bottom" and similar terms are used herein to describe the spatial relationship of one device / element or anatomical structure to another device / element or anatomical structure, it is understood that these terms are used herein for ease of description to describe the positional relationships between the elements / structures illustrated in the drawings. The spatially relative terms are intended to encompass different orientations of the elements / structures during use or operation in addition to the orientation depicted in the drawings. For example, an element / structure described as "above" another element / structure may represent a position that is below or to the side of such other element / structure with respect to the subject patient or alternative orientations of the element / structure, and vice versa.

[0027] The term "associated with" is used herein in accordance with its broad and ordinary meaning. For example, when a first feature, element, component, device, or member is described as "associated with" a second feature, element, component, device, or member, such description should be understood as indicating that the first feature, element, component, device, or member is physically coupled, attached, connected, integrated with, at least partially embedded within, or otherwise physically associated with the second feature, element, component, device, or member, whether directly or indirectly.

[0028] An access sheath can be used to introduce a medical instrument / instrument into a patient's anatomy. For example, the access sheath can be positioned within a desired anatomy and a medical instrument can be advanced through the sheath to access a target location within the patient. In some cases, at least a portion of the access sheath can be designed to expand from an initial state having a first diameter to an expanded state having a second, larger diameter. This allows the sheath to be introduced into the patient at a smaller diameter and expand to a larger diameter once positioned, thereby minimizing damage to the patient's anatomy and / or the access sheath.

[0029] In some cases, the medical device may not be able to withstand excessive pushing force (e.g., due to the relatively weak configuration of the device). Pushing force may refer to the amount of work or force exerted axially on the medical device to allow the medical device to move axially through the access sheath (which may cause radial expansion of the access sheath). Furthermore, excessive pushing force on the medical device may cause the medical device to be ejected from the access sheath. To minimize the pushing force required to advance the medical device, the distal end (and / or other portions) of the access sheath may be formed of a relatively weak / delicate structure / material. However, this may cause damage to the distal end (or other portions) of the access sheath as it is advanced into the patient.

[0030] The present disclosure describes devices, systems, and methods relating to a dilator / introducer that includes an encapsulation feature configured to protect an access sheath, such as a distal end, or other portion of the access sheath. For example, the dilator can be coupled to the access sheath to introduce the access sheath into a desired anatomy in a manner that protects and / or provides additional support to the distal end and / or other portion of the access sheath. The dilator can include an elongate shaft configured to be received within the access sheath and an encapsulation feature disposed on a distal portion of the elongate shaft. The encapsulation feature can be configured to cover the distal end of the access sheath when the dilator is positioned within the access sheath and the access sheath is advanced into the desired anatomy. Once positioned within the anatomy, the encapsulation feature can be separated from the distal end of the access sheath, such as by advancing the dilator distally. The dilator can then be removed from the access sheath. Thus, the expander can provide additional structure / support to the access sheath while it is being advanced into the patient, thereby minimizing damage to the access sheath and / or the patient's anatomy, which can be useful in a variety of situations, such as when the access sheath is implemented as an expandable sheath that includes a relatively weak / fragile feature and / or in other situations.

[0031] FIG. 1 illustrates an exemplary dilator / introducer 102 including an encapsulating feature 104, according to one or more embodiments. The dilator 102 (also referred to as an "encapsulating dilator 102") may include an elongate shaft / member 106 and an encapsulating / covering / protecting / encapsulating feature 104 disposed on the elongate shaft 106 and configured to couple to an access sheath (not shown in FIG. 1). The dilator 102 may be configured to be disposed within a lumen within an access sheath such that a distal end portion of the dilator 102 extends beyond the distal end of the access sheath, as discussed in further detail below, which may allow the encapsulating feature 104 to couple to the access sheath. When coupled to the access sheath, the encapsulating feature 104 may at least partially cover / support / hold the distal end of the access sheath to protect the access sheath from damage when advanced into a desired anatomical structure, such as via a percutaneous access pathway.

[0032] The encapsulating feature 104 may include one or more flexible / movable members configured to selectively expand / open to allow an access sheath to be at least partially positioned underneath the encapsulating feature 104. In an embodiment, the one or more flexible members may be configured to apply a radially inward force such that the one or more flexible members collapse towards the elongate shaft 106 of the dilator 102. For example, the one or more flexible members may be configured to collapse / close around the elongate shaft 106 (in the absence of an access sheath or another device underneath the encapsulating feature 104) as shown in FIG. 1. In this example, the encapsulating feature 104 includes multiple tabs / fingers / protrusions that extend longitudinally towards the proximal end of the dilator 102. However, other types of features / components may be implemented as discussed in more detail below.

[0033] The dilator 102 may include a distal taper / expanding portion / section 108 configured to dilate / expand the anatomical structure into which the dilator 102 is inserted. The tapered portion 108 may taper toward the distal end 110 of the dilator 102 (e.g., the outer diameter of the dilator 102 may decrease toward the distal end 110 of the dilator 102). The tapered portion 108 may provide an atraumatic point for advancing an associated access sheath into the desired anatomical structure. The tapered portion 108 may be positioned between the distal end 110 of the dilator 102 and at least a portion of the encapsulation feature 104 (e.g., the proximal end of the encapsulation feature 104). Although many examples show the tapered portion 108 having a particular shape / size, any type of expanding shape / size may be implemented.

[0034] The dilator 102 may also include a recess / shaft / portion / section 112 (also referred to as a "recess 112") configured to receive one or more flexible members of the encapsulation feature 104 when the one or more flexible members are collapsed / closed. The recess 112 may include a smaller outer diameter / dimension than the outer diameter of another portion of the dilator 102 adjacent to the recess 112, such as the body / inner body / shaft / portion / section 114. The body 114 may have a relatively uniform outer diameter / dimension, or another configuration. The recess 112 may function as a space / void to allow the proximal end of the encapsulation feature 104 to collapse to a smaller outer diameter / dimension than the body 114, thereby providing a smooth transition for the encapsulation feature 104 to be removed from (e.g., translated proximally through) the access sheath. The recess 112 may be referred to as a "neck" that separates the distal tapered portion 108 from the remainder of the dilator 102 (e.g., from the body / shaft 114 of the dilator 102). Although the recess 112 is shown in many embodiments, the recess 112 may be eliminated in some implementations.

[0035] The dilator 102 may be implemented with separate components coupled together or with a single component. In one view, the body 114, the recess 112, and / or the tapered portion 108 are implemented as separate components coupled / attached to one another. In another view, the dilator 102 is implemented with a single shaft having different sections having the properties / characteristics of the body 114, the recess 112, and / or the tapered portion 108. For ease of discussion, one or more of the body 114, the recess 112, and / or the tapered portion 108 may be referred to as the elongated shaft 106. For example, a description of the encapsulation feature 104 attached to the elongated shaft 106 may refer to the encapsulation feature 104 attached to the body 114, the recess 112, and / or the tapered portion 108.

[0036] The elongate shaft 106 may include or be coupled to a hub 116 disposed at a proximal end 118 of the dilator 102. The hub 116 may be configured to hold the access sheath (not shown) in place while the access sheath and the dilator 102 are advanced into the patient. For example, the hub 116 may be coupled to the proximal end of the access sheath to maintain the access sheath in a relatively fixed position between the hub 116 and the encapsulation feature 104. This may prevent the access sheath from sliding over the dilator 102 as it is introduced into the patient. Additionally, the hub 116 may be configured to provide irrigation / aspiration or other functionality, such as through a lumen within the dilator 102. In some embodiments, the dilator 102 may include a lumen extending from the proximal end 118 to the distal end 110, which may provide a path for another device / liquid / gas to travel. Exemplary configurations of a dilator coupled to an access sheath are shown in FIGS. 5 and 6.

[0037] Although various components of the expander 102 are discussed in the context of separate or integral components, the components of the expander 102 may be implemented as integral or separate components. For example, one or more of the hub 116, the elongate shaft 106, and / or the encapsulation features 104 may be implemented as a single / integral component or as separate components.

[0038] Figure 2 shows example details of the extender 102 from Figure 1, in accordance with one or more embodiments. Various example features of the extender 102 are shown in Figure 2 (and elsewhere in the drawings) for illustrative purposes, although the features may be implemented in other manners. Additionally, the extender 102 may include other features.

[0039] As shown, the tapered portion 108 of the dilator 102 may be implemented in a variety of shapes / sizes / forms. For example, the tapered portion 108 may be implemented in any of the forms / shapes / sizes 108(A)-108(C). The tapered portion 108 may include a form / shape / size designed for a particular situation, such as the anatomy into which the dilator 102 is inserted, the medical procedure in which the dilator 102 is implemented, the type of access sheath in which the dilator 102 is implemented, etc. To illustrate, the tapered portion 108 may include a taper ratio designed for implementation at a particular access point / medical procedure. Although various examples show the encapsulation feature 104 as being coupled to the tapered portion 108, the encapsulation feature 104 may be coupled to other portions of the dilator 102, such as portions that may or may not be tapered.

[0040] The recess 112 may include a form / shape / size that allows the encapsulation feature 104 to be folded around the shaft of the dilator 102. For example, the recess 112 may taper downward toward the proximal end 118 of the dilator 102 such that the encapsulation feature 104 may be folded around the shaft of the recess 112, as shown in FIG. 2. The recess 112 may be shaped / sized / formed to fill the shape / size / form of the encapsulation feature 104, such as the inner diameter / shape of the encapsulation feature 104. In this example, the recess 112 creates a step that connects with the elongate shaft 106 (e.g., the inner portion 114 of the elongate shaft 106).

[0041] The encapsulation feature 104 may be implemented in a variety of forms / styles. In one embodiment illustrated at 104(A), the encapsulation feature 104 includes a plurality of tabs / fingers / protrusions extending longitudinally toward the proximal end 118 of the elongate shaft 106. Here, the encapsulation feature 104(A) is implemented as a separate component from the elongate shaft 106 and attached to the shaft 106 using adhesive / fasteners. However, the encapsulation feature 104(A) may be integral with the shaft 106. The tabs in this implementation are at least somewhat tapered toward the proximal end of the tab, as shown in more detail in Figures 3-1 and 3-2. The encapsulation feature 104(A) may include openings / holes 202 that aid in adhering / attaching the encapsulation feature 104(A) to the shaft 106, such as to allow adhesive to flow through the openings / holes 202. In some cases, the encapsulation feature 104(A) may be pressed onto the elongate shaft 108, with at least a portion of the elongate shaft 106 extruding into the opening / hole 202, which may help hold the encapsulation feature 104(A) in place on the elongate shaft 108. In another embodiment, shown at 104(B), the encapsulation feature 104 includes a plurality of tabs / fingers / protrusions and an overmold / overlay material 204 that assists in coupling the encapsulation feature 104(B) to the elongate shaft 106. The overmold 204 can cover the encapsulation feature 104 and / or at least a portion of the tapered portion 108. The overmold 204 can be disposed within the opening / hole 202 and attached to the elongate shaft 106.

[0042] In a further embodiment, as shown at 104(C), the encapsulation feature 104 includes multiple tabs / fingers / protrusions that are integral with the elongate shaft 106. The tabs may be formed in a variety of ways such that at least the proximal ends of the tabs are independently movable relative to the elongate shaft 108. Although implementations 104(A)-(C) include tabs having substantially the same shape / size (e.g., tapered toward the proximal ends of the tabs), the tabs may be implemented in other shapes / sizes, such as those shown in 104(D), or alternative configurations / shapes / sizes. Additionally, the tabs may have different shapes / sizes / configurations relative to one another.

[0043] In yet another embodiment, shown at 104(D), the containment feature 104 includes multiple tabs / fingers / protrusions that are flared toward the proximal end of the tab. For ease of illustration, the tabs are shown in an expanded / open state, however, the tabs may be configured to fold onto the elongate shaft 106 in a manner similar to the tabs described above for other implementations.

[0044] In another embodiment shown at 104(E), the encapsulating feature 104 is implemented with a flexible / stretchable / moldable substance / material (sometimes referred to as a "non-tab based encapsulating feature" or a "stretchable encapsulating feature"). For example, the encapsulating feature 104(E) may be implemented with a polymer or another flexible material that can be stretched / bent / moved to cover the distal end of the access sheath. In an embodiment, the encapsulating feature 104(E) may include silicone, NEUSoft®, or another material with specific elasticity, tear, or other characteristics.

[0045] In an embodiment, the encapsulation feature 104 of implementations 104(A)-104(D) may be implemented with a metal, such as a shape memory alloy. For example, the encapsulation feature 104 may include Nitinol or another shape memory alloy configured to maintain a particular configuration / shape (e.g., default / initial / manufactured configuration). This structure / material may be useful to help the encapsulation feature 104 fold toward the elongate shaft 106, such as to hold the access sheath during insertion of the access sheath or to fold around the elongate shaft 106 during retraction of the dilator 102 from the access sheath. In many cases, the shape memory alloy may allow the encapsulation feature 104 to automatically fold / close inward toward the elongate shaft 106. Alternatively or additionally, the encapsulation feature 104 may be implemented with other substances / materials, such as polymers, ceramics, etc.

[0046] Although various features are shown with respect to a particular implementation of the encapsulation feature 104, any of these features may be used / substituted. Additionally, other features may be implemented with the encapsulation feature 104. For example, the encapsulation feature 104 may be implemented with actuation components / systems, such as pull wires, fluid / gas, etc., configured to control the state of the encapsulation feature 104. To illustrate, the expander 102 may be implemented with a pull wire that extends from the proximal end 118 through the elongate shaft 106, travels up through the distal end of the encapsulation feature 104, travels back toward the proximal end of the encapsulation feature 104, and arrives at the proximal end of the encapsulation feature 104. The pull wire may be actuated to expand or collapse a tab or other element of the encapsulation feature 104. In another embodiment, the expander 102 may be implemented with a balloon disposed under at least a portion of the encapsulation feature 104 and configured to expand / contract to control the state of the tab. The balloon may be inflated / deflated via a fluid / gas passageway that runs through the elongate shaft 106 .

[0047] The expander 102 can comprise a variety of materials / substances, such as polymers, metals, ceramics, etc. In some embodiments, the encapsulating feature 104 comprises a different type of material than the remainder of the expander 102. In other embodiments, the encapsulating feature 104 is implemented with the same type of material.

[0048] As mentioned above, the hub / locking mechanism 116 can be configured to maintain / lock the access sheath (not shown) in a fixed position on the dilator 102. For example, the hub 116 can be coupled to the proximal end 118 of the elongate shaft 106 and configured to selectively engage the access sheath to hold the access sheath in a fixed position between the hub 116 and the encapsulation feature 104. The hub 116 can implement a locked / coupled state / configuration to maintain the access sheath between the hub 116 and the encapsulation feature 104 and can implement an unlocked / uncoupled state / configuration to allow the dilator 102 to be removed from the access sheath.

[0049] In one embodiment, shown at 116(A), the hub 116 includes a threaded component / shaft configured to be threaded onto the proximal end 118 of the elongate shaft 106. Here, the hub 116(A) may include other larger diameter components or other features (relative to the diameter of the elongate shaft 106) configured to prevent the access sheath from sliding off the proximal end 118 of the elongate shaft 106 when the access sheath is placed over the elongate shaft 106.

[0050] In another embodiment, as shown at 116(B), the hub 116 is implemented with a clamping / clip feature, such as a C-clamp or C-clip, configured to clamp / clip onto the proximal end 118 of the elongate shaft 106. In this embodiment, the hub 116(B) may include a plate / coupling mechanism 204 configured to clamp onto the proximal end 118 of the elongate shaft 106. The plate 204 may be coupled to a threaded shaft or another element configured to be screwed downward / upward to move the plate 204.

[0051] In yet another embodiment, as shown at 116(C), the hub 116 is implemented with a turn lever / knob 206 rotatably coupled to the elongate shaft 106 and configured to rotate relative to the elongate shaft 106. For example, in a locked state, the lever 206 can be positioned at 90 degrees relative to the longitudinal axis of the elongate shaft 106, as shown in FIG. 2, which can prevent the access sheath (not shown) from sliding off the proximal end 118 of the elongate shaft 106. In an unlocked state, the lever 206 can be positioned in line with the longitudinal axis of the elongate shaft 106, allowing the access sheath to be removed from the elongate shaft 106 (e.g., over the lever 206).

[0052] In some cases, the hub 116 may include a port 208 configured to couple / connect to a system that provides irrigation / suction through the lumen of the dilator 102. Additionally or alternatively, the port 208 may provide an access path for a guidewire to slide through the lumen of the dilator 102. The lumen may extend longitudinally through the introducer 102 from the proximal end 118 to the distal end 110.

[0053] Although various examples are illustrated / discussed herein in the context of cylindrical dilators, the dilators may be implemented in other forms.

[0054] 3-1 and 3-2 show an exemplary encapsulation feature / component 104 implemented with multiple tabs 302(A)-302(C) tapering toward the proximal end, according to one or more embodiments. FIG. 3-1 provides a perspective view of the encapsulation feature 104, and FIG. 3-2 provides a side view of the encapsulation feature 104. Here, the encapsulation feature 104 is implemented as a separate component from the elongate shaft 106. This example may be similar or identical to any of the tab implementations discussed herein having tapered tabs, where the encapsulation feature 104 is separate from the elongate shaft 106 (e.g., implementations 104(A)-104(B) of FIG. 2).

[0055] As shown, the tabs 302 taper toward the proximal end 304 of the encapsulation feature 104. This allows the tabs 302 to avoid contacting each other at the proximal end 304 when in a folded state. For example, the tabs 302 may be folded around a narrower shaft while avoiding contacting each other at the proximal end 304. The amount of taper and / or the length of the taper may be adjusted / configured for a particular situation. Additionally, the tabs 302 may be circumferentially spaced apart from each other to help provide enough space for the tabs 302 to fold inwardly. This may create space between the tabs 302. Here, the encapsulation feature 104 is implemented with three tabs, but any number of tabs may be implemented.

[0056] One or more characteristics of the tabs 302 may be designed to exhibit particular characteristics. For example, the shape / length / thickness of the tabs 302, the number of tabs 302, etc. may be designed to (i) provide a particular amount of inward radial / compressive force when coupled to the access sheath to retain the tip of the access sheath (which in some cases may exert a radially outward force) and / or (ii) allow the encapsulation feature 104 to be separated / detached from the tip of the access sheath without damaging the tip of the access sheath. Although the tabs 302 are shown in particular configurations / shapes / sizes, the tabs 302 may include other configurations / shapes / sizes.

[0057] The encapsulation feature 104 includes a coupling / attachment feature / section 306 configured to couple the tab 302 to an elongate shaft, such as the elongate shaft 106 (not shown in FIGS. 3-1 and 3-2). The coupling feature 306 may be referred to as a "waist feature 306." The waist feature 306 may include a hole / opening 202 to allow adhesive to fill the opening / hole 202 to aid in adhering / attaching the encapsulation feature 104 to a component. As mentioned above, in some cases, an overmold may be provided within the opening 202 to aid in attaching the encapsulation feature 104 to a component. The inner diameter of the waist feature 306 may be the same (or within a threshold amount) as the outer diameter of the elongate shaft to which the encapsulation feature 104 is installed / attached.

[0058] The encapsulating feature 104 may be formed from a variety of materials, such as metals (e.g., shape memory alloys such as Nitinol), polymers / plastics (e.g., polyethylene terephthalate (PET), etc.), ceramics, etc. In some instances, the encapsulating feature 104 may be implemented as a shape-set feature that attempts to maintain a particular shape / form. Additionally, in some examples, the encapsulating feature 104 may be laser cut.

[0059] FIG. 4 illustrates an example of an access sheath 402 that may be implemented with one or more introducers / dilators and / or other components discussed herein, according to one or more embodiments. This example illustrates an expandable access sheath, where one or more portions of the access sheath are expandable from an initial diameter to a larger diameter. The access sheath 402 may be elastically / temporarily deformable / expandable or permanently deformable / expandable. In an example, an elastically / temporarily deformable / expandable sheath may refer to a sheath that attempts to maintain / return to an initial diameter / dimension when an external force is removed. On the other hand, a permanently deformable / expandable sheath may refer to a sheath that attempts to maintain an expanded diameter / dimension. In some cases, the access sheath 402 includes one or more permanently expandable portions and one or more temporary / elastically expandable portions. In an example, the expandable access sheath is implemented with a mesh / braid / stent structure / shaft that is attached / bonded to a material. For example, the expandable access sheath can include a stent frame formed of a shape memory alloy (e.g., Nitinol) with material disposed within and / or on the stent frame. A sheath expander, medical instrument, or other device can be advanced through the access sheath to expand the expandable access sheath from an initial inner diameter to a larger inner diameter.

[0060] In some instances, the distal end 404 of the access sheath 402 includes different properties / structures / materials than one or more adjacent / other portions / sections of the access sheath 402. For example, the distal end 404 may lack a portion of the stent / mesh structure of an adjacent inner portion / section of the access sheath 402, as shown in FIG. 4, where the distal end 404 is weaker / more fragile than the adjacent portions of the access sheath 402. In embodiments, having a weaker / more fragile structure at the distal end 404 can reduce the amount of pushing force required to advance an instrument distally out of the distal end 404 of the access sheath 402, which can prevent damage to the instrument and / or the access sheath 402. This can further minimize damage to the patient's anatomy by avoiding the instrument being quickly expelled from the distal end 404 of the access sheath 402. However, the distal end 404 may be implemented with properties / structures / materials that are stronger / less fragile (or the same) than other portions of the access sheath 402. In an embodiment, the distal end 404 of the access sheath 402 is configured to flare outward (e.g., expand radially depending on the structure / material of the distal end 404), where a dilator having encapsulation features (as discussed herein) may be coupled to the distal end 404 to temporarily hold the distal end of 404 in place and prevent it from flaring outward while the access sheath 402 is advanced into the patient.

[0061] Although various embodiments are illustrated / discussed herein in the context of a cylindrical sheath, the sheath may be implemented in other forms.

[0062] 5 illustrates an exemplary configuration of the access sheath 402 from FIG. 4 coupled to a dilator 102 (also collectively referred to as a "medical system"), the dilator 102 being implemented with a tab-based containment feature 104, according to one or more embodiments. As shown, the access sheath 402 is disposed over the introducer 102, between the hub 116 and the containment feature 104. The distal end 404 of the access sheath 402 can slide under the containment feature 104, such as to the point where the distal end 404 is in contact with the dilator 102 (e.g., under the containment feature 104). Here, the distal portion of the dilator 102 extends beyond the access sheath 402. The hub 116 can then be fastened against and / or disposed over the proximal end of the access sheath 402. 5, the access sheath 402 and dilator 102 may be introduced into the patient's anatomy (e.g., percutaneously through various tissue layers) in a manner that provides additional support to the access sheath 402. For example, the encapsulating feature 104 of the dilator 102 may protect the distal end 404 of the access sheath 402 and / or the inner portion 114 of the dilator 102 (not shown in FIG. 5) may provide support to the access sheath 402.

[0063] In embodiments, the dilator 102 and the access sheath 402 can be sized such that the devices form a relatively tight fit with one another. For example, the inner diameter of the access sheath 402 and the outer diameter of the dilator 102 (e.g., inner portion 114) can be sized to be relatively close / same size (e.g., within a threshold amount of each other). The relatively tight fit of the dilator 102 and the access sheath 104 can help provide additional structure / support to the access sheath 402 as it is advanced into the desired anatomy.

[0064] 6 illustrates an exemplary configuration of the access sheath 402 from FIG. 4 coupled to a dilator 102 that includes a flexible / stretchable / moldable encapsulating feature 104 (e.g., a non-tab structure), according to one or more embodiments. As also described above, the access sheath 402 is disposed over the introducer 102 between the hub 116 and the encapsulating feature 104, where the encapsulating feature 104 at least partially covers the distal end of the access sheath 402. Because the encapsulating feature 104 is formed of a flexible / stretchable / moldable material, the encapsulating feature 104 can conform to the shape of the distal end of the access sheath 402 to form a relatively tight fit with the distal end of the access sheath 402.

[0065] 7-1-7-3 show various example states / configurations of the containment feature 104 of the expander 102, according to one or more embodiments. In these figures, the containment feature 104 is implemented with multiple tabs configured / arranged for opening / expanding and closing / folding.

[0066] FIG. 7-1 illustrates the tab 104 in a fully opened / expanded / loaded state, with the dilator 102 configured to receive the access sheath 402. The tab 104 can be opened / expanded to the shown arrangement using a variety of techniques, such as manually by a user, by a loading device configured to open / expand the tab 104, by an actuation component (e.g., a pull wire, balloon, etc.). Once the tab 104 is opened / expanded, the access sheath 402 can be advanced over the dilator 102 and positioned such that at least a portion of the distal end of the access sheath 402 is below the tab 104, as shown. In an embodiment, since the access sheath 402 is loaded onto the dilator 102, this configuration may be referred to as the loaded state.

[0067] FIG. 7-2 illustrates the tab 104 in a closed / folded state over at least a portion of the access sheath 402. The tab 104 can be coupled (e.g., radially folded) to the access sheath 402. In some cases, when the force used to open the tab 104 (such as the configuration of FIG. 7-1) is removed, the tab 104 can automatically fold / close onto the distal end of the access sheath 402. In the state of FIG. 7-2, the access sheath 402 and dilator 102 can be introduced into the desired anatomy (e.g., the encapsulation feature 104 forms an encapsulation around the distal end of the access sheath 402 to protect the access sheath 402). In an embodiment, because the tab 104 is coupled / covered to the access sheath 402, this configuration may be referred to as a delivery / coupled / partially folded / encapsulated state.

[0068] FIG. 7-3 illustrates the tab 104 in a closed / folded state on the elongate shaft 106, such as within the recess 112. In this configuration, the dilator 102 can be retracted from the access sheath 402. The tab 104 can now be folded radially onto the elongate shaft 106. As shown, the outer diameter of the recess 112 can have a smaller outer diameter than the outer diameter of the adjacent portion of the elongate shaft 106. This can provide space for the tab 104 to be folded onto the shaft 106 to provide a relatively low profile configuration. In an embodiment, the proximal end of the tab 104 in the folded state can have an outer diameter that is the same as or smaller than the outer diameter of the adjacent portion of the elongate shaft 106 (e.g., body 114), as shown in FIG. 7-3. Further, in embodiments, the maximum outer diameter of the containment feature 104 in the collapsed state may be less than (or in some cases greater than) the outer diameter of the elongate shaft 106 (e.g., body 114) and / or the inner diameter of the access sheath 402. The configuration of FIG. 7-3 may be referred to as a fully collapsed / closed / removed state because the tabs 104 are folded onto the elongate shaft 106.

[0069] 8-1-8-3 show an example flow diagram of a process 800 for advancing an access sheath into an anatomical feature using a dilator including an encapsulating feature, according to one or more embodiments of the present disclosure. FIGs. 9-1-9-3 show images of example anatomical structures and equipment associated with the process 800 of FIGs. 8-1-8-3, illustrating aspects of the process 800, according to one or more implementations thereof. The process 800 is shown as a series of blocks. The blocks can be arranged in any order and are not necessarily limited to the particular order shown. The operations / acts of the blocks can be performed by a physician / user and / or a device / component / system.

[0070] In FIG. 8-1, at block 802, the process 800 includes attaching the encapsulation feature and / or the hub of the dilator / introducer to the access sheath. For example, as shown in image 902, the encapsulation feature 104 (which may be disposed on a distal portion / section of the dilator 102) may be positioned over at least a portion of the distal end of the access sheath 402. The hub 116 (not shown in FIG. 9-1) may also be coupled / attached to the proximal end of the access sheath 402 to hold / maintain the access sheath 402 between the hub 116 and the encapsulation feature 104. In some cases, the dilator 102 may be attached / attached to the access sheath 402 during preparation for the procedure. However, the dilator 102 and the access sheath 402 may be coupled / attached at other times.

[0071] In some embodiments where the encapsulation feature 104 is implemented with a tab (as shown in FIG. 9-1 ), the tab 104 can be opened / expanded to allow the access sheath 402 to be properly positioned for attachment to the access sheath 402. Once open, the access sheath 402 can be advanced distally under the tab 104, and the tab 104 can be folded and collapsed / closed over the distal end of the access sheath 402. To illustrate, the dilator 102 can be translated distally through the access sheath 402, the tab 104 can expand radially, the dilator 102 can be translated proximally a certain amount, and the tab 104 can be folded over the distal end of the access sheath 402.

[0072] Additionally, in some embodiments where the encapsulation feature 104 is implemented with a stretchable / non-tab encapsulation feature 104 (as shown in FIG. 6 ), the encapsulation feature 104 may be coupled to the access sheath 402 by rolling / bending or otherwise moving the encapsulation feature 104 toward the distal end of the dilator 102. Once the encapsulation feature 104 is moved out of the way, the access sheath 402 may be advanced distally to be adjacent the rolled encapsulation feature 104. The encapsulation feature 104 may then be rolled back / repositioned onto the distal end of the access sheath 402.

[0073] In some cases, a loading / coupling device is used to couple the encapsulation feature 104 to the access sheath 402. For example, the loading device may have a funnel-like / tapered shaft that tapers toward the distal end of the loading device. The loading device may also have a lumen with an inner diameter larger than the outer diameter of the dilator 102. The inner diameter of the loading device may also be larger than the outer diameter of the access sheath 402. To couple the encapsulation feature 104 to the access sheath 402, the loading device may be advanced over the dilator 102 such that the distal end of the loading device is positioned below the encapsulation feature 104, thereby opening / expanding the encapsulation feature 104 radially outward. The loading device may act in a wedge-like fashion that is positioned below the encapsulation feature 104. When the encapsulating feature 104 is in an open / expanded state on the loading device, the access sheath 402 can be advanced distally over the expander 102 through a lumen in the loading device (e.g., between the loading device and the expander 102). The access sheath 402 can be positioned below the encapsulating feature 104. The loading device can then be retracted proximally away from the encapsulating feature 104 to fold / close / position the encapsulating feature 104 over the distal end of the access sheath 402.

[0074] At block 804, the process 800 includes advancing the dilator / introducer and access sheath into the anatomical structure. For example, as shown in image 904, the access sheath 402 with the dilator 102 attached (e.g., combined / joined dilator and access sheath) may be inserted through the skin and / or other tissue into the blood vessel / other anatomical structure 905. The dilator 102 may progressively dilate / expand the anatomical structure while providing an atraumatic edge / point for inserting the access sheath 402 into the blood vessel 905. The dilator 102 may help minimize damage to the access sheath 402 and / or the patient's anatomy. The dilator 102 may be advanced into the patient such that at least a distal end of the access sheath 402 is located within the blood vessel 905. This can create a port / access point to the blood vessel 905 (e.g., for a therapy / delivery device to access the blood vessel 905), as discussed in more detail below. In some cases, a needle / guidewire is first inserted into the patient to create a passage / pathway for the dilator 102. In cases where a guidewire is implemented, the dilator 102 can be advanced over the guidewire (e.g., through the lumen of the dilator 102) to navigate the dilator 102 within the patient's anatomy. In some cases, the encapsulation feature 104 is implemented to protect or hold the distal end of the access sheath 402, such as when the distal end of the access sheath 402 has a relatively weak / fragile configuration and / or has a tendency to open when no force is applied to the distal end.

[0075] In FIG. 8-2, at block 806, the process 800 includes translating the dilator / introducer distally to remove the encapsulation feature from the access sheath. For example, as shown in image 906, the dilator 102 may be further inserted into the access sheath 402 (e.g., the access sheath 402 may remain relatively stationary while the dilator 102 advances distally). The distal translation of the dilator 102 may cause the encapsulation feature 104 to be removed from the access sheath 402. Once the encapsulation feature 104 is removed from the access sheath 402, the encapsulation feature 104 may be folded / closed onto the elongate shaft of the dilator 102, such as into a recess on the elongate shaft, as shown in image 908. In an embodiment, the hub 116 (not shown in FIG. 9-2) of the dilator 102 is unlocked / disconnected from the access sheath 402 before the dilator 102 can be translated distally.

[0076] 8-3, in block 808, the process 800 includes removing the dilator / introducer from the access sheath. For example, as shown in image 910, the dilator 102 may be retracted / translated proximally to remove the dilator 102 from the access sheath 402. The access sheath 402 may be held in place or may otherwise remain relatively stationary while the dilator 102 is retracted.

[0077] At block 810, the process 800 includes advancing a medical instrument through the access sheath. For example, as shown in image 912, once the dilator 102 is removed from the access sheath 402, a medical instrument 913 may be advanced through the access sheath 402. The medical instrument 913 may include a delivery catheter and / or any other type of delivery / treatment device may be used in the medical procedure. In an embodiment, the medical instrument 913 is navigated through a blood vessel 905 and / or other anatomical structure along a guidewire or other target location / anatomical feature.

[0078] In some non-limiting illustrations, the process 800 is performed to deliver a prosthetic device to a target location and perform a therapy at the target location. For example, an access sheath 402 can be inserted into an artery / vein to provide an access point for a delivery catheter, or other therapy device, to enter the artery or vein. The access sheath 402 can be introduced into the artery / vein with a dilator 102 to prevent damage to the patient and / or the access sheath 402. The dilator 102 can then be removed and a medical instrument can be inserted through the access sheath 402 and the artery / vein to reach the target location, deploy the medical device, perform a therapy at the target location, etc.

[0079] Any of the various systems, devices, equipment, etc. in this disclosure may be sterilized (e.g., using heat, radiation, ethylene oxide, hydrogen peroxide, etc.) to ensure that they are safe for use on patients, and the methods described herein may include sterilization of the associated systems, devices, equipment, etc. (e.g., using heat, radiation, ethylene oxide, hydrogen peroxide, etc.).

[0080] Further description of the embodiment Example 1. An expander comprising: an elongate shaft configured to be received within an access sheath, the elongate shaft tapering toward a distal end of the elongate shaft; and an encapsulation feature disposed on a distal portion of the elongate shaft, the encapsulation feature including a plurality of tabs extending toward a proximal end of the elongate shaft, the plurality of tabs configured to cover the distal end of the access sheath when the elongate shaft is disposed within the access sheath.

[0081] Example 2: Any of the examples described herein, particularly the expander of Example 1, wherein the elongate shaft includes a recess configured to receive the plurality of tabs in a collapsed state, the recess including an outer diameter smaller than an outer diameter of a portion of the elongate shaft adjacent the distal portion.

[0082] Example 3: The expander according to any of the embodiments described herein, particularly any of Examples 1 or 2, wherein the plurality of tabs are configured to be folded onto the elongate shaft to implement a folded state.

[0083] Example 4: The expander of any of the examples described herein, particularly examples 1-3, wherein the encapsulating feature comprises a shape memory alloy.

[0084] Example 5: The expander of any of the embodiments described herein, particularly embodiments 1-4, wherein the encapsulating feature includes a coupling feature configured to couple the encapsulating feature to the elongate shaft.

[0085] Example 6: The dilator of any of the embodiments described herein, particularly embodiments 1-5, wherein the encapsulation feature is integral with the elongate shaft.

[0086] Example 7: The expander of any of the embodiments described herein, particularly embodiments 1-6, wherein the elongate shaft includes a tapered portion between the distal end of the elongate shaft and the encapsulation feature, the tapered portion tapering toward the distal end of the elongate shaft.

[0087] Example 8: The expander of any of the embodiments described herein, particularly embodiments 1-7, further comprising a hub coupled to the proximal end of the elongate shaft and configured to selectively engage the access sheath to hold the access sheath in place between the hub and the encapsulation feature.

[0088] Example 9: The dilator of any of the examples described herein, particularly examples 1-8, wherein the dilator is sterile.

[0089] Example 10: A medical system comprising: an access sheath including an inner lumen, a distal end, and a proximal end; and a dilator configured to be received within the inner lumen, the dilator including an elongate shaft and an encapsulation feature disposed on a distal portion of the elongate shaft, the encapsulation feature including a plurality of longitudinally extending tabs, the dilator configured to implement an encapsulated state in which the plurality of tabs are coupled to the distal end of the access sheath, and a folded state in which the plurality of tabs are radially folded on the elongate shaft.

[0090] Example 11: Any of the examples described herein, particularly example 10, wherein the elongate shaft includes a recess configured to receive the plurality of tabs in the folded state, the recess including an outer diameter smaller than a portion of the elongate shaft adjacent the distal portion.

[0091] Example 12: The medical system of any of the examples described herein, particularly examples 10 or 11, wherein the encapsulating feature comprises a shape memory alloy.

[0092] Example 13: The medical system of any of the embodiments described herein, particularly embodiments 10-12, wherein the encapsulation feature is integral with the elongate shaft.

[0093] Example 14: Any of the examples described herein, particularly examples 10-13, wherein the elongate shaft tapers between the encapsulation feature and the distal end of the elongate shaft.

[0094] Example 15: Any of the embodiments described herein, particularly embodiments 10-14, further comprising a hub coupled to the proximal end of the elongate shaft and configured to hold the access sheath in a fixed position between the hub and the encapsulation feature when the expander is disposed within the access sheath.

[0095] Example 16: The medical system of any of the examples described herein, particularly examples 10-15, wherein at least one of the access sheath or the expander is sterilized.

[0096] Example 17: A method of accessing an anatomical feature, the method comprising: attaching a containment feature of a dilator to a distal end of an access sheath, the containment feature comprising a plurality of tabs configured to cover the distal end of the access sheath; advancing the access sheath into an anatomical structure with the dilator attached; translating the dilator distally to remove the containment feature from the access sheath; and translating the dilator proximally to remove the dilator from the access sheath.

[0097] Example 18: The method of any of the examples described herein, particularly example 17, further comprising attaching a hub of the expander to a proximal end of the access sheath to hold the access sheath between the hub and the encapsulation feature, wherein the advancing of the access sheath occurs with the hub attached to the proximal end of the access sheath.

[0098] Example 19: The method of any of the examples described herein, particularly example 17 or 18, wherein the expander includes recesses configured to receive the tabs.

[0099] Example 20: The method of any of the examples described herein, particularly example 19, wherein the distal translation of the expander causes the tabs to collapse into the recess.

[0100] Example 21: The method of any of the embodiments described herein, particularly embodiments 17-20, wherein attaching the encapsulating feature of the expander to the distal end of the access sheath includes translating the expander distally through the access sheath, radially expanding the plurality of tabs, translating the expander proximally, and folding the plurality of tabs onto the distal end of the access sheath.

[0101] Example 22: The method of any of the examples described herein, especially examples 17-21, wherein the encapsulating feature comprises a shape memory alloy.

[0102] Example 23: The method of any of the embodiments described herein, particularly embodiments 17-22, wherein at least one of the dilator or the access sheath is sterilized.

[0103] Additional Examples Depending on the embodiment, certain acts, events, or functions of any of the processes or algorithms described herein may be performed in a different order, added, combined, or omitted entirely, and thus, in a particular embodiment, not all described acts or events are required to practice a process.

[0104] In particular, conditional language used herein, such as "can," "could," "might," "may," "eg," and the like, unless specifically stated otherwise or understood otherwise within the context in which it is used, is intended to have its ordinary meaning and is generally intended to convey that a particular embodiment includes certain features, elements, and / or steps, but not other embodiments. Thus, such conditional language is generally not intended to imply that features, elements, and / or steps are in any manner required for one or more embodiments, or that one or more embodiments necessarily include logic for determining, with or without authorial input or prompting, whether those features, elements, and / or steps are included in or should be performed in any particular embodiment. Terms such as "comprising," "including," "having," and the like, are synonymous and used in their ordinary sense and are used in an inclusive, non-limiting manner and do not exclude additional elements, features, acts, operations, and the like. Also, the term "or" is used in its inclusive sense (and not its exclusive sense), for example, when used to connect a list of elements, such that the term "or" means one, some, or all of the elements in the list. Conjunctive language such as the phrase "at least one of X, Y, and Z" is understood with the context as being used generally to convey that an item, term, element, etc., can be either X, Y, or Z, unless specifically stated otherwise. Thus, such conjunctive language is not generally intended to imply that a particular embodiment requires that at least one of X, at least one of Y, and at least one of Z, respectively, be present.

[0105] In the above description of the embodiments, it should be understood that various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. However, this method of disclosure should not be interpreted as reflecting an intention that any claim requires more features than are expressly recited in that claim. Moreover, any component, feature, or step illustrated and / or described in a particular example herein can be applied to or used with any other embodiment. Moreover, no component, feature, step, or group of components, features, or steps is necessarily required or essential to each embodiment. Thus, the scope of the subject matter disclosed and / or claimed below should not be limited by the specific embodiments described above.

[0106] It should be understood that certain sequential terms (e.g., "first" or "second") may be provided for ease of reference and do not necessarily imply physical characteristics or order. Thus, as used herein, sequential terms (e.g., "first," "second," "third," etc.) used to modify elements such as structures, components, operations, etc., do not necessarily indicate a priority or order of the element relative to any other elements, but rather may generally distinguish an element from other elements having a similar or identical name (except for the use of sequential terms). In addition, as used herein, the indefinite articles ("a" and "an") may indicate "one or more" rather than "one." Furthermore, an operation performed "based on" a condition or event may also be performed based on one or more other conditions or events not expressly recited.

[0107] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art to which the examples belong. Furthermore, terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and are not to be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0108] Spatially relative terms such as "outer", "inner", "upper", "lower", "bottom", "up", "vertical", "horizontal", and similar terms may be used herein for ease of description to describe the relationship between one element or component and another element or component as depicted in the drawings. It is understood that the spatially relative terms are intended to encompass different orientations of the device during use or operation in addition to the orientation depicted in the drawings. For example, if the device depicted in the drawings is turned over, a device that is positioned "under" or "directly below" another device may be positioned "above" another device. Thus, the exemplary term "under" may include both a lower position and an upper position. The device may also be oriented in other directions, and thus the spatially relative terms may have different interpretations depending on the orientation.

[0109] Unless expressly stated otherwise, comparison and / or quantitative terms such as "less," "more," "greater than," and the like are intended to encompass the notion of equivalence. For example, "less" can mean "less than" as well as "less than" in the strictest mathematical sense.

Claims

1. 1. An expander comprising: an elongate shaft configured to be received within an access sheath, the elongate shaft tapering toward a distal end of the elongate shaft; an encapsulation feature disposed on a distal portion of the elongate shaft, the encapsulation feature including a plurality of tabs extending toward a proximal end of the elongate shaft, the plurality of tabs configured to cover a distal end of the access sheath when the elongate shaft is disposed within the access sheath.

2. 2. The expander of claim 1, wherein the elongate shaft includes a recess configured to receive the plurality of tabs in a collapsed state, the recess including an outer diameter smaller than an outer diameter of a portion of the elongate shaft adjacent the distal portion.

3. The dilator of claim 1 or 2, wherein the plurality of tabs are configured to fold onto the elongate shaft to implement a folded state.

4. The expander of any one of claims 1 to 3, wherein the encapsulating feature comprises a shape memory alloy.

5. The dilator of any of claims 1 to 4, wherein the encapsulating feature includes a coupling feature configured to couple the encapsulating feature to the elongate shaft.

6. The dilator of any one of claims 1 to 5, wherein the encapsulating feature is integral with the elongate shaft.

7. The expander of any one of claims 1 to 6, wherein the elongate shaft includes a tapered portion between the distal end of the elongate shaft and the encapsulation feature, the tapered portion gradually decreasing toward the distal end of the elongate shaft.

8. The expander of any one of claims 1 to 7, further comprising a hub coupled to the proximal end of the elongate shaft, the hub configured to selectively engage the access sheath to hold the access sheath in place between the hub and the encapsulation feature.

9. 1. A health care system comprising: an access sheath including an inner lumen, a distal end, and a proximal end; 11. A medical system comprising: a dilator configured to be received within the internal lumen, the dilator comprising an elongate shaft and an encapsulation feature disposed on a distal portion of the elongate shaft, the encapsulation feature comprising a plurality of longitudinally extending tabs, the dilator configured to implement a encapsulated state in which the plurality of tabs are coupled to the distal end of the access sheath, and a folded state in which the plurality of tabs are radially folded on the elongate shaft.

10. 10. The medical system of claim 9, wherein the elongate shaft includes a recess configured to receive the plurality of tabs in the collapsed state, the recess including a smaller outer diameter than a portion of the elongate shaft adjacent the distal portion.

11. The medical system of claim 9 or 10, wherein the encapsulating feature comprises a shape memory alloy.

12. The medical system of any of claims 9 to 11, wherein the encapsulating feature is integral with the elongate shaft.

13. The medical system of any of claims 9 to 12, wherein the elongate shaft is tapered between the encapsulation feature and the distal end of the elongate shaft.

14. 13. The medical system of any of claims 9-12, further comprising a hub coupled to a proximal end of the elongate shaft, the hub configured to hold the access sheath in a fixed position between the hub and the encapsulation feature when the expander is disposed within the access sheath.

15. 1. A method for accessing anatomical features, the method comprising: Attaching a containment feature of a dilator to a distal end of an access sheath, the containment feature including a plurality of tabs configured to cover the distal end of the access sheath; advancing the access sheath with the dilator attached into the anatomy; translating the dilator distally to remove the encapsulation feature from the access sheath; and and proximally translating the dilator to remove the dilator from the access sheath.

16. 16. The method of claim 15, further comprising attaching a hub of the dilator to a proximal end of the access sheath to retain the access sheath between the hub and the containment feature, and wherein the advancing of the access sheath occurs with the hub attached to the proximal end of the access sheath.

17. 17. The method of claim 15 or claim 16, wherein the dilator includes recesses configured to receive the tabs.

18. The method of claim 17 , wherein the distal translation of the dilator causes the plurality of tabs to collapse into the recesses.

19. 19. The method of any of claims 15-18, wherein attaching the encapsulation feature of the dilator to the distal end of the access sheath comprises translating the dilator distally through the access sheath, radially expanding the plurality of tabs, translating the dilator proximally, and folding the plurality of tabs onto the distal end of the access sheath.

20. The method of any of claims 15 to 19, wherein the encapsulating feature comprises a shape memory alloy.

Images