Steerable catheter device with keys

Abstract

Disclosed herein are devices, systems and methods relating to steerable catheters. The steerable catheter (100) includes a first working line, an inner catheter (120) and an outer catheter (110). The inner catheter has an outer surface defining a longitudinally extending keyway. The outer catheter has an inner surface defining a lumen and longitudinally extending splines that project radially inwardly into the outer catheter lumen. The outer catheter lumen is operable to receive the inner catheter, and the splines of the outer catheter are operable to engage the keyway of the inner catheter. The splines define a spline lumen operable to receive the first working line.

Description

Technical Field

[0001] This application claims the benefit of Provisional Application No. 63 / 214,592, filed Jun. 24, 2021, which is hereby incorporated by reference in its entirety for all purposes.

[0002] Field The present disclosure generally relates to medical devices, systems, and methods. More specifically, the present disclosure relates to devices, systems, and methods involving steerable catheters.

Background Art

[0003] Background A catheter is a tubular medical device that can be inserted into a blood vessel, body cavity, or duct of the body and manipulated using a portion that extends outside the body. Typically, a catheter is relatively thin and flexible, which facilitates advancement and retraction along a non-linear path. Catheters typically use a long, flexible tube made of a synthetic plastic material. Catheters can be used for a wide variety of purposes, including positioning diagnostic and / or therapeutic devices within the body. For example, a catheter can be used for positioning an internal imaging device, deploying an implantable device (e.g., a stent, stent graft, inferior vena cava filter), and / or delivering energy (e.g., an ablation catheter). Desirable properties of a catheter tube include the ability to transmit force from the proximal end of the catheter to the distal end. Also, it is desirable for the catheter to be flexible so that it can navigate a tortuous path within a body cavity without kinking. Also, it is desirable for the catheter to be robust so that it can withstand manipulation of the device within the body cavity while torque required for a particular procedure is being applied.

[0004] The steerable mechanism is widely available for catheter delivery and navigation in various minimally invasive surgical procedures. These can be used to deliver or push other devices such as catheters or pacemaker leads through tortuous anatomical structures or to identify the location of arterial or venous access points. A typical steering mechanism involves the use of a pull wire connected to the distal end of the catheter tip and operable at the proximal end of the catheter. With this configuration, the tip of the catheter can be bent proportionally in response to the tension applied to the pull wire. By applying tension to the pull wire, the catheter can take various complex curves depending on each lumen through which the pull wire passes. In many cases, these pull wires are disposed within dedicated lumens, increasing the complexity of manufacturing (e.g., maintaining lumen tolerances along the length of the catheter). This reason, along with the need for additional space (e.g., within the handle and across the diameter of the catheter) to accommodate at least the associated components of the steering mechanism, often results in high manufacturing costs. Similarly, the tip of a catheter using such a pull wire can only deflect in a single plane, thereby limiting the effectiveness of this type of catheter in reaching many desired treatment sites.

[0005] Minimally invasive procedures that benefit from the use of a steerable catheter include, among others, transcatheter mitral valve repair / replacement (TMVR) and transcatheter mitral chordal repair / replacement (TMCR). The mitral valve controls the blood flow between the heart chambers on the left side of the heart and pumps oxygenated blood into the body. The mitral valve can have two main problems: stenosis (narrowing of the valve orifice) or leakage (regurgitation). As a result, abnormal blood flow through the mitral valve can cause the heart to work harder and ultimately lead to heart failure. TMVR and TMCR provide minimally invasive options for treating mitral valve stenosis, regurgitation, or some combination of the two. These procedures typically involve multiple catheters that access the mitral valve through complex navigation that requires movement in multiple planes. For example, to access the mitral valve, an outer catheter can be advanced over an introducer from a puncture of the femoral vein and through the inferior vena cava to reach the right atrium. The outer catheter can be punctured through the fossa ovalis of the atrial septum and then advanced through the fossa and curved so that its distal end faces over the mitral valve. Positioning of the distal end over the mitral valve can be achieved by shaping the outer catheter so that it assumes a shaped position when the introducer is withdrawn and / or by manipulating the outer catheter to the desired position using in-plane and out-of-plane deflections. These deflections can be easily performed by restraining the nested catheter in the rotational direction using a key groove and a corresponding key, both of which should be rigid enough to maintain the rotational relationship between the nested catheters. This approach is presented merely as an example, and it can be understood that other approaches, such as access via the jugular vein, femoral artery, port access, or direct access, can also be used.

[0006] To enhance cost-effectiveness and facilitate manufacturing, steerable catheters often involve the use of polymer extrusions. As described above, steerable systems that include pull wires require a separate lumen for each pull wire and may use keyways for rotational restraint. Polymer extrusions can be mass-produced, but they have the drawback of manufacturing variations, particularly with respect to shapes that extend along measurable portions of the catheter, such as keyways or keys formed within the catheter. Variations in the polymer extrusions and the keyways or key extensions increase as the length of the polymer extrusion increases. This variation can potentially result in unnecessary compromises in catheter operation and overall reliability. Summary of the Invention

[0007] Abstract The present disclosure provides improved devices, systems, and methods involving catheters with multi-plane steering and keyed configurations. In particular, embodiments of the present disclosure include a nested catheter having an outer sheath with a keyed profile and a paired inner sheath. Such embodiments are useful for steerable sheaths and catheters as well as non-steerable sheaths and catheters and provide several advantages. For example, such embodiments employ a relatively simple structure that ensures more uniform structural features, such as structural features (e.g., splines, keyways, etc.) that extend along the measurable length of the catheter, compared to more conventional methods. Further, when used as a steerable catheter, the present disclosure uses components of the drive mechanism (e.g., nested actuating lines or pull wires disposed within a spline) to provide mechanical strength between desired locations, such as between splines that engage a keyway, without the need for additional components. If desired, this mechanical strength can be further enhanced by adding additional components nested within the spline, keyway, or both, without departing from the scope of the present disclosure. In another example, embodiments that employ a single continuous catheter liner can prevent air or fluid within the lumen of the catheter from undesirably escaping to other portions of the catheter having components with which such fluid or air is not intended to come into contact. In this way, degradation and reduced operation of these components (such as actuating lines) can be prevented.

[0008] According to one example (Example 1), an operable catheter includes a first actuation line, an inner catheter, and an outer catheter. The inner catheter has an inner catheter proximal end, an inner catheter distal end, an outer surface of the inner catheter that optionally defines a keyway extending longitudinally, and an inner surface of the inner catheter that defines an inner catheter lumen. The outer catheter has an outer catheter proximal end, an outer catheter distal end, an outer surface of the outer catheter, and an inner surface of the outer catheter that optionally defines an outer catheter lumen and a spline. The spline extends longitudinally and optionally projects radially inwardly into the outer catheter lumen. The outer catheter lumen is operable to receive the inner catheter, and the spline of the outer catheter is operable to engage the keyway of the inner catheter. The spline defines a spline lumen operable to receive the first actuation line.

[0009] In addition to Example 1, according to another example (Example 2), the operable catheter further includes an outer catheter actuation ring coupled to the outer catheter distal end. The first actuation line is coupled to the outer catheter actuation ring.

[0010] In addition to Example 1 or Example 2, according to another example (Example 3), the operable catheter further includes a second actuation line, where the inner catheter defines an inner catheter actuation line lumen from the inner catheter proximal end to the inner catheter distal end and is operable to receive the second actuation line therethrough. The second actuation line extends from the inner catheter proximal end to the inner catheter distal end and is coupled thereto.

[0011] In addition to Example 3, according to another example (Example 4), the operable device further includes an inner catheter actuation ring coupled to the inner catheter distal end. The second actuation line is coupled to the inner catheter actuation ring.

[0012] In addition to any one of Examples 1 to 4, according to another example ("Example 5"), each of the spline and the key groove is parallel to the central axis of the steerable catheter.

[0013] In addition to any one of Examples 1 to 5, according to another example ("Example 6"), the inner catheter includes at least one locking collar that defines the key groove of the inner catheter.

[0014] In addition to any one of Examples 1 to 6, according to another example ("Example 7"), the inner catheter includes a first elongate tubular member that defines the outer surface of the inner catheter, and the key groove is defined by the first elongate tubular member.

[0015] In addition to any one of Examples 1 to 7, according to another example ("Example 8"), the inner surface of the outer catheter further defines a plurality of splines, and the outer surface of the inner catheter further defines a plurality of respective key grooves.

[0016] In addition to Examples 1 to 8, according to another example ("Example 9"), the inner surface of the outer catheter defines two splines that are located approximately 180 degrees apart around the outer catheter, and the outer surface of the inner catheter defines two respective key grooves that are located 180 degrees apart around the inner catheter.

[0017] In addition to any one of Examples 1 to 8, according to another example ("Example 10"), the inner surface of the outer catheter defines three splines that are located approximately 90 degrees apart around the outer catheter, and the outer surface of the inner catheter defines three respective key grooves that are located approximately 90 degrees apart around the inner catheter.

[0018] In addition to any one of Examples 1 to 8, according to another example ("Example 11"), the inner surface of the outer catheter defines three splines that are located approximately 120 degrees apart around the outer catheter, and the outer surface of the inner catheter defines three respective key grooves that are located approximately 120 degrees apart around the inner catheter.

[0019] In addition to any one of Examples 1 to 11, according to another example (Example 12), the steerable catheter includes a deflectable region at or around the distal end of the outer catheter, the keyway extends along the length of the inner catheter toward the distal end of the inner catheter, and terminates near the deflectable region of the outer catheter.

[0020] In addition to any one of Examples 1 to 12, according to another example (Example 13), the inner catheter is slidably received within the outer catheter along the length of the keyway.

[0021] In addition to any one of Examples 1 to 13, according to another example (Example 14), the steerable catheter includes a hemostatic seal between the inner surface of the outer catheter and the outer surface of the inner catheter.

[0022] According to another example (Example 15), a steerable catheter includes a first actuation line, an inner catheter, an outer catheter, and optionally a keyed locking collar. The first actuation line has a proximal portion and a distal portion. The inner catheter defines a first elongate tubular member having an inner catheter proximal end and an inner catheter distal end, and an inner catheter inner surface defining an inner catheter outer surface and an inner catheter lumen. The keyed locking collar optionally includes a keyway and is coupled to the inner catheter. The outer catheter defines a second elongate tubular member having an outer catheter proximal end and an outer catheter distal end, and an outer catheter inner surface defining an outer catheter outer surface and an outer catheter lumen, the outer catheter inner surface defining splines. The splines optionally extend longitudinally and optionally project radially inwardly into the outer catheter lumen. The outer catheter lumen is operable to receive the inner catheter therethrough, and the splines engage the keyway. The splines define a spline lumen for slidably receiving the first actuation line. The first actuation line optionally extends along the outer catheter, and the distal portion of the first actuation line is optionally coupled near the distal end of the outer catheter.

[0023] In addition to Example 15, according to another example (Example 16), the keyed locking collar is integrally formed with the first elongate tubular member of the inner catheter.

[0024] In addition to Example 15 or 16, according to another example (Example 17), the keyed locking collar extends radially beyond the outer diameter of the inner catheter.

[0025] In addition to any one of Examples 15 - 17, according to another example (Example 18), the length of the keyed locking collar is shorter than the length of the inner catheter.

[0026] In addition to any one of Examples 15 - 18, according to another example (Example 19), the inner surface of the outer catheter defines two splines located approximately 180 degrees apart around the outer catheter, and the outer surface of the inner catheter defines two respective keyways located approximately 180 degrees apart around the inner catheter.

[0027] In addition to any one of Examples 15 - 19, according to another example (Example 20), the inner surface of the outer catheter defines three splines located approximately 90 degrees apart around the outer catheter, and the outer surface of the inner catheter defines three respective keyways located approximately 90 degrees apart around the inner catheter.

[0028] According to another example (Example 21), a method of treating a patient. The method optionally includes obtaining an operable catheter similar to those disclosed elsewhere herein, including an operable catheter associated with any one of Examples 1 - 20. The method includes advancing the outer catheter into a body cavity. The method includes advancing the inner catheter into the outer catheter, thereby engaging the splines with the keyways. The method optionally includes actuating a first actuation line, thereby causing movement at the distal end of the outer catheter.

[0029] In addition to Example 21, according to another example ( "Example 22"), the steerable catheter further includes a handle at the proximal end of the outer catheter. The handle is operably coupled to a first actuation line such that actuation of the handle actuates the first actuation line. Actuating the first actuation line may, in some cases, include performing at least one actuation of the handle.

[0030] The foregoing examples are merely examples and should not be construed as limiting or narrowing the scope of the concepts of the invention provided separately by the present disclosure. Although multiple examples are disclosed, other embodiments will be apparent to those skilled in the art from the following detailed description which illustrates and describes the exemplary examples. Accordingly, the drawings and the detailed description are not inherently limiting and should be considered to be essentially exemplary.

Brief Description of the Drawings

[0031] Brief Description of the Drawings The accompanying drawings are included to provide a further understanding of the present disclosure, are incorporated herein and constitute a part hereof, illustrate embodiments, and together with the description serve to explain the principles of the present disclosure.

[0032]

Figure 1

[0033]

Figure 2A

[0034]

Figure 2B

[0035]

Figure 2C

[0036]

Figure 2D

[0037]

Figure 2E

[0038]

Figure 3

[0039]

Figure 4

Mode for Carrying Out the Invention

[0040] Detailed Description Definitions and Terms This disclosure is not intended to be read restrictively. For example, the terms used in this application should be read broadly in the sense relationships that a person skilled in the art would ascribe to such terms.

[0041] With respect to the term of inaccuracy, the terms "about" and "approximately" can be used interchangeably to refer to a measured value that includes the recited measured value and a measured value that also includes any measured value reasonably close to the recited measured value. A measured value reasonably close to the recited measured value deviates from the recited measured value by a reasonably small amount, as would be understood and readily ascertainable by a person of ordinary skill in the relevant art. Such deviations can be due to measurement errors, differences in calibration of measurement and / or manufacturing equipment, human error in reading and / or setting of measured values, fine adjustments made to optimize performance and / or structural parameters taking into account differences in measured values related to other components, specific implementation scenarios, inaccurate adjustment and / or operation of an object by a person or machine, etc. If it is determined that a person of ordinary skill in the relevant art cannot readily ascertain the value of such a reasonably small difference, the terms "about" and "approximately" can be understood to mean plus or minus 10% of the recited value.

[0042] "Manipulable" is defined as the ability to orient the portion of the catheter on the distal side of the manipulable segment at an angle with respect to the portion of the catheter on the proximal side of the manipulable segment. "Manipulation" can include any known method of manipulation that can be utilized to orient the portion of the catheter on the distal side of the manipulable segment at an angle with respect to the portion of the catheter on the proximal side of the manipulable segment, including methods that utilize multiple manipulable segments. Such methods can include, but are not limited to, remote application of force (e.g., electrical (e.g., wired or wireless), mechanical, hydraulic, pneumatic, magnetic, etc.) involving transmission of force by various means including, but not limited to, pull wires and / or push wires, hydraulic lines, air lines, magnetic coupling, or electrical conductors, and can include, but are not limited to, transmission by operation of push wires and / or pull wires, filaments, tubes, and / or cables. Further, the catheter body can be constructed to have segments with different flexibility or compression characteristics than other segments of the catheter body. In embodiments having an inner tubular body and an outer tubular body, the outer tubular body can have one or more manipulable segments with push / pull wires that are fixed at the distal end of the manipulable segment and extend through one or more lumens of the outer tubular wall to the attachment to the steering control of the handle. Manipulation of the outer tubular body can similarly manipulate the inner tubular body. In a variant, the inner tubular body can be manipulable, and manipulation of the inner tubular body can similarly manipulate the outer tubular body.

[0043] Description of Various Embodiments One of ordinary skill in the art will readily understand that the various aspects of the present disclosure can be implemented by any number of methods and apparatuses configured to perform the intended functions. It should also be noted that the accompanying drawings referred to herein are not necessarily drawn to scale and may be exaggerated in order to illustrate the various aspects of the present disclosure, and in that regard, the drawings should not be construed as limiting.

[0044] FIG. 1 shows a catheter system 100 according to an embodiment of the present disclosure. Referring to this figure, an embodiment of the catheter system 100 includes a plurality of catheters. The catheter system 100 includes an outer catheter 110 having a proximal end 114 of the outer catheter, a distal end 116 of the outer catheter, and an outer catheter lumen 118 therethrough, and an inner catheter 120 having a proximal end 124 of the inner catheter, a distal end 126 of the inner catheter, and an inner catheter lumen 128 therethrough. As shown in the figure, the inner catheter 120 is coaxially disposed within the outer catheter lumen 118. The distal end 116 of the outer catheter, the distal end 126 of the inner catheter, or both are typically sized to be able to pass through a body cavity, such as a blood vessel lumen, through the body cavity. The outer catheter lumen 118 is sized to allow the inner catheter 120 to pass through. The inner catheter lumen 128 is sized to allow various devices to pass through.

[0045] The outer catheter 110, the inner catheter 120, or both have a steering mechanism for positioning the distal end 116 of the outer catheter, the distal end 126 of the inner catheter, or both in a desired direction, and embodiments thereof will be described in detail later. The outer catheter 110 and the inner catheter 120 can be independently steerable (e.g., such that the outer catheter 110 can be steered in a first direction and the inner catheter 120 can be steered in a second direction different from the first direction). The outer catheter 110 and the inner catheter 120 can together form a compound curvature in a single direction. Next, a tool can be advanced through the outer catheter 110 and the inner catheter 120, through the compound curve, in a desired direction towards its target. Steering of the outer catheter 110 and the inner catheter 120 can be achieved by actuation of one or more steering mechanisms. Actuation of the steering mechanism is typically achieved using an actuator disposed on a handle 150 connected to each of the outer catheter 110 and the inner catheter 120.

[0046] In an embodiment, in addition to being steerable, the catheter can be shape-set. Shape-setting includes setting a specific curvature in the catheter before use (e.g., by heat or a shape memory alloy). Since the catheter is generally flexible, when the catheter is loaded onto a guide wire or other introducer, as the introducer advances through the shaping region, the shape-set catheter straightens out. After being placed at a desired location within the patient's body, the introducer is removed and the catheter can return to the set shape. As described above, curvature can be formed in the outer catheter 110 and the inner catheter 120, for example, by shape-setting or steering. To provide more advanced control and a variety of possible curvatures, a steering mechanism can be used to create the curvature and position the catheter. In some embodiments, the steering mechanism includes an actuation line (e.g., a cable or pull wire) within the wall of the catheter.

[0047] As will be described in further detail below, the outer catheter 110 can include an actuation line (e.g., a cable or pull wire, not shown) that is slidably received within a lumen that extends longitudinally within the wall of the outer catheter 110. In an embodiment, the entrance to the lumen within the wall of the catheter may coincide with the outer surface 111 of the outer catheter. By applying tension in a generally proximal direction, the actuation line causes the distal end 116 of the outer catheter to curve in the direction of a first actuation line (not shown), as indicated by arrow 142. Providing a second actuation line (not shown) on the opposite side of the catheter similarly causes the distal end 116 of the outer catheter to curve in the opposite direction, as indicated by arrow 144, when tension is applied to that actuation line. This arrangement allows the distal end to be steered in opposite directions and enables the curvature to be corrected or adjusted during operation. For example, the curvature can be reduced by a combination of reducing the tension on a corresponding actuation line when tension is applied to one actuation line to create a curve and applying tension to the opposite actuation line. There is a combination of actuation lines (e.g., four pull wires arranged equidistantly around the outer catheter 110) that allow the distal end to curve in at least four directions indicated by arrows 142, 144, 146, 148. It can be understood that these arrows also relate to the inner catheter 120. For example, the actuation line within the inner catheter 120 can create a second curve of the inner catheter 120 and the actuation line.

[0048] Such actuation lines and associated lumens may be arranged in any configuration (e.g., single or pair, symmetric or asymmetric, etc.) and any number of actuation lines (e.g., 1, 2, 3, 4, etc.) may be used. Such a configuration allows for curvature in all directions and around various axes and planes. The actuation lines can be fixed at any position along the length of the catheter by suitable methods such as adhesion, bundling, soldering, potting, etc. When tension is applied to the actuation line, a curvature is formed in the proximal direction from the attachment point of the actuation line. Thus, depending on the position of the attachment point of the actuation line, curvature can be formed throughout the length of the catheter. In the configuration, the actuation line is attached near the distal end of the catheter and, optionally, to an actuation ring embedded in the outer catheter 110, as further described below. In some such embodiments, a second set of actuation lines may be coupled to another actuation ring embedded at a different position in the catheter. Further, depending on the application, the lumen housing the actuation line may be straight or curved.

[0049] The illustrated arrows correspond to the articulation positions of the catheter system 100 that can be useful in accessing a patient's mitral valve. For example, in a method of using the catheter system 100 to access the mitral valve, to access the mitral valve, the outer catheter 110 can be tracked from the puncture site in the patient's vasculature to the patient's heart (e.g., entering the femoral vein and passing through the inferior vena cava to the right atrium) over an introducer (e.g., dilator or guide wire). The outer catheter 110 can then be punctured through the fossa of the atrial septum and then advanced through the fossa and curved by a first curve such that the distal end faces over the mitral valve. Positioning of the outer catheter distal end 116 over the mitral valve can be achieved by shaping the outer catheter 110, which assumes this position when the dilator and guide wire are retracted and / or by maneuvering the outer catheter 110 to the desired position. This approach is merely illustrative, and it is understood that other approaches can be used, such as accessing via the jugular vein, femoral artery, port access, or direct access.

[0050] In an embodiment, the steerable catheter can include a deflectable member 105 at or around the distal end 126 of the inner catheter, and the keyway can extend along the length of the inner catheter 120 toward the distal end 126 of the inner catheter and can terminate near the deflectable member 105 of the outer catheter 110. FIG. 1 shows an embodiment of a catheter system 100 that includes such a deflectable member 105. As described above, the catheter is flexible and can bend along the contour of the blood vessel in the body into which it is inserted. The deflectable member 105 can be disposed at the distal end 126 of the inner catheter of the catheter system 100. The catheter system 100 includes a handle 150 that can be disposed at the proximal end 114 of the outer catheter, the proximal end 124 of the inner catheter, or both. During a procedure in which the deflectable member 105 is inserted into a patient's body, the handle 150 and a portion of the catheter system 100 remain outside the body. A user (e.g., a physician, technician, interventionalist) of the catheter system 100 can control the position and various functions of the catheter system 100. For example, the user can hold the handle 150 and operate a portion thereof to control the deflection of the deflectable member 105. In this regard, the deflectable member 105 can be selectively deflectable. The handle 150 and its operable portion can be configured such that the operable portion of the handle 150 with respect to the handle 150 is maintained, thereby enabling the selected deflection of the deflectable member 105 to be maintained. Such maintenance of position can be achieved at least in part by, for example, friction (e.g., friction between a sliding portion and a stationary portion of the handle 150), a detent, and / or any other suitable means. The catheter system 100 can be removed from the body by pulling (e.g., by pulling the handle 150). Further, the user can insert an interventional device (e.g., a diagnostic device and / or a therapeutic device) through the interventional device inlet. Next, the user can feed the interventional device through the catheter system 100 and move the interventional device to the distal end 126 of the inner catheter of the catheter system 100.For example, the electrical interconnection between the image processor and the deflectable member can be wired via an electronic port and through the catheter system 100.

[0051] Figures 2A - 2E show various views of the outer catheter 110 and the inner catheter 120 of the catheter system 100 according to a first embodiment of the present disclosure. Figure 2A shows a side view of the outer catheter 110 of the catheter system 100. Figure 2B shows a side view of the keyed mandrel 200 for forming the catheter system 100. Figure 2C shows a side view of section C - C of Figure 2A. Figure 2D shows a side view of section A - A of Figure 2A. Figure 2E shows a side view of the inner catheter 120 of the catheter system 100. As a theme throughout the present disclosure, in embodiments, one or more features discussed with respect to one catheter (e.g., the outer catheter) can be included in another catheter (e.g., the inner catheter).

[0052] The systems shown in Figures 2A - 2E are provided as examples of various features of the system, and while combinations of these illustrated features are clearly within the scope of the invention, the examples and the figures are not intended to suggest that the inventive concepts provided herein are limited to fewer features, additional features, or alternative features to one or more of those features shown in Figures 2A - 2E. For example, in various embodiments, the components and / or characteristics of the systems shown in Figures 2A - 2E can include other components and / or characteristics described with reference to Figure 1 or Figure 3. It should be understood that the reverse is also true. One or more of the components shown in Figures 2A - 2E can be used in addition to, or in place of, the components shown in Figure 1 or Figure 3. For example, the components and / or characteristics of the systems shown in Figures 2A - 2E can be used in relation to the components and / or characteristics of other devices shown in Figure 3.

[0053] In a first embodiment of the present disclosure, the steerable catheter can include a first actuation line 201, an inner catheter 120, and an outer catheter 110. The steerable catheter can be similar to the catheter systems disclosed elsewhere herein, including the catheter system 100 as shown herein. The first actuation line 201 can be, for example, a cable or a pull wire. The inner catheter 120 can have an inner catheter proximal end 124, an inner catheter distal end 126, an inner catheter outer surface 121 defining a longitudinally extending keyway 222, and an inner catheter inner surface 223 defining an inner catheter lumen 128. The outer catheter 110 can have an outer catheter proximal end 114, an outer catheter distal end 116, an outer catheter outer surface 111, and an outer catheter inner surface 213 defining an outer catheter lumen 118 and a spline 212. The spline 212 can extend longitudinally and project radially inwardly within the outer catheter lumen 118. The outer catheter lumen 118 can be operable to receive the inner catheter 120, and the spline 212 of the outer catheter 110 can be operable to engage the keyway 222 of the inner catheter 120.

[0054] The spline 212 can define a spline lumen 119 operable to receive (e.g., slidably receive) the first actuation line 201. By disposing the first actuation line 201 within the spline 212, additional mechanical support can be provided to withstand wear and torque. An additional relatively high durometer material monofilament or mandrel can be disposed within this spline 212 and disposed around the first actuation line 201 to make the spline 212 more robust (e.g., increase its mechanical strength). Further, for additional mechanical support, a braided or coiled-reinforced liner can be used for the spline 212 (e.g., to form the spline lumen 119). In addition to the first actuation line 201, the spline lumen 119 can provide various other functions as a working lumen in any combination without departing from the scope of the present disclosure, such as the ability to transfer fluid (e.g., contrast media or diluent), the ability to receive electrical wires or leads (e.g., for tool operation, pressure measurement, etc.). Similarly, the present disclosure can include one or more such working lumens separate from the spline lumen 119 that receives the first actuation line 201 or any other actuation line without departing from the scope of the present disclosure.

[0055] The relative movement between the inner catheter 120 and the outer catheter 110 can be such that both are freely slidable longitudinally but are constrained in the rotational direction (e.g., by a combination of splines 212 and keyways 222). The splines 212 can contribute to these constraints. For example, at or around a point along the length of the outer catheter 110, the inner surface 213 of the outer catheter can transition from a contoured inner diameter (e.g., having splines 212) to a smooth diameter. Such an embodiment includes splines 212 that extend from near the proximal end 114 of the outer catheter or around it towards the distal end 116 of the outer catheter and terminate near the distal end 116 of the outer catheter. This transition can occur at any length along the outer catheter 110. In an embodiment, this transition occurs at the transition to the deflectable member 105 of the catheter (further described above). The transition of the inner surface 213 of the outer catheter can advantageously provide a mechanical hard stop to the inner catheter 120 since the keyway 222 is no longer guided by the spline 212. Additionally or alternatively, the transition of the inner surface 213 of the outer catheter can advantageously provide a geometry at the distal surface that can be angled (e.g., via conventional catheter tipping techniques).

[0056] In an embodiment, the inner catheter 120 can be slidably received within the outer catheter 110 along the length of the keyway 222. In an embodiment, each of the spline 212 and the keyway 222 can be parallel to the central axis of the steerable catheter. In an embodiment, the inner catheter 120 can include a first elongate tubular member 227 that defines an outer surface 121 of the inner catheter. In such an embodiment, the keyway 222 can be defined by the first elongate tubular member 227. For example, the length of the keyway 222 can extend from the proximal end 124 of the inner catheter toward the distal end 126 of the inner catheter. In other examples, the length of the keyway 222 can extend from the proximal end 124 of the inner catheter toward the distal end 126 of the inner catheter and terminate near the distal end 126 of the inner catheter (e.g., in front of the coiled or braided portion of the inner catheter 120). Alternatively, the keyway 222 can extend from the distal end 126 of the inner catheter toward the proximal end 124 of the inner catheter and terminate near the proximal end of the inner catheter. In some embodiments, the keyway 222 can extend intermediate along the length of the inner catheter 120 so as to terminate near both the proximal end 124 and the distal end 126 of the inner catheter. In any case, the length (and other dimensions such as depth) of the keyway 222 can vary among these examples as long as the inner catheter 120 is maintained in a state of being slidably received within the outer catheter 110 along the length of the keyway 222 (e.g., by the spline 212).

[0057] By spacing a plurality of splines 212 around the inner surface 213 of the outer catheter, a balanced fit is provided and the orientation of the inner catheter 120 within the outer catheter 110 can be ensured. In that regard, the inner surface 213 of the outer catheter can define a plurality of splines 212, and the outer surface 121 of the inner catheter can define a plurality of respective keyways 222. Any number (e.g., 1, 2, 3, 4, etc.) of splines 212 or keyways 222 can be used. In an embodiment, the inner surface 213 of the outer catheter can define two splines 212 that are located approximately 180 degrees apart around the outer catheter, and the outer surface 121 of the inner catheter can define two respective keyways 222 that are located 180 degrees apart around the inner catheter. With just such two splines 212, while providing a balanced fit, it can be possible for the inner catheter 120 to fit within the outer catheter 110 in two orientations (e.g., a first orientation rotated 0 degrees about the central axis and a second orientation rotated 180 degrees about the central axis). Thus, in some embodiments, more than three splines 212 can be used just to allow for one such orientation. For example, in an embodiment, the inner surface 213 of the outer catheter can define three splines 212 that are located approximately 90 degrees apart around the outer catheter, and the outer surface 121 of the inner catheter can define three respective keyways 222 that are located approximately 90 degrees apart around the inner catheter. In an embodiment, the inner surface 213 of the outer catheter can define three splines 212 that are located approximately 120 degrees apart around the outer catheter, and the outer surface 121 of the inner catheter can define three respective keyways 222 that are located approximately 120 degrees apart around the inner catheter. Although described in terms of having a respective number of splines 212 and keyways 222, it should be noted that the number of splines 212 and keyways 222 may vary in embodiments without departing from the scope of the present disclosure.

[0058] In an embodiment, the steerable catheter can include an outer catheter actuation ring 250 coupled to the distal end 116 of the outer catheter. A first actuation line 201 can be coupled to the outer catheter actuation ring 250. In an embodiment, the steerable catheter can include a second actuation line 202. For example, the inner catheter 120 can be operative to define an actuation line lumen of the inner catheter 120 from the proximal end 124 of the inner catheter to the distal end 126 of the inner catheter and receive the second actuation line 202 therethrough. The second actuation line 202 can extend from the proximal end 124 of the inner catheter to the distal end 126 of the inner catheter and can be coupled thereto. In an embodiment, the steerable catheter can include an inner catheter 120 actuation ring coupled to the distal end 126 of the inner catheter. Also, the second actuation line 202 can be coupled to the inner catheter 120 actuation ring. Each actuation ring may be embedded in a corresponding catheter (e.g., outer catheter 110 or inner catheter 120).

[0059] As described below, in an embodiment, the catheter liner 215 can be a single continuous catheter liner 215 extending from the proximal end 114 of the outer catheter to the distal end 116 of the outer catheter. The catheter liner 215 can define the inner surface 213 of the outer catheter. Such a catheter liner 215 can advantageously be free of seams or joints required to connect separate portions of a discontinuous liner. These seams or joints often create points of failure in the catheter assembly because air or fluid can leak therethrough and enter other parts of the catheter assembly. This event can adversely affect components of the catheter assembly, such as the first actuation line 201, that are intended to be shielded from air or fluid leaking from the catheter liner 215, potentially causing corrosion or degradation of their operation.

[0060] FIG. 3 shows a side view of the inner catheter 120 with a keyed locking collar 260 for a catheter system according to a second embodiment of the present disclosure.

[0061] The devices shown in FIG. 3 are provided as examples of various features of the devices, and while combinations of these illustrated features are clearly within the scope of the present invention, the examples and the figures thereof are not intended to suggest that the inventive concepts provided herein are limited to fewer features, additional features, or alternative features to one or more of those features shown in FIG. 3. For example, in various embodiments, the components and / or characteristics of the devices shown in FIG. 3 can include other components and / or characteristics described with reference to FIGS. 1 or 2A-2E. It should also be understood that the reverse is also true. One or more of the components shown in FIG. 3 can be used in addition to, or alternatively to, the components shown in FIGS. 1 or 2A-2E. For example, the components and / or characteristics of the devices shown in FIG. 3 can be used in combination with other components and / or characteristics of other devices shown in FIGS. 2A-2E.

[0062] In a second example of the present disclosure, the inner catheter 120 of the steerable catheter can include at least one keyed locking collar 260 that defines a keyway 222 of the inner catheter 120. In all other respects, the steerable catheter is the same as those described elsewhere herein, including those of the first embodiment. For example, the steerable catheter can include a first actuation line 201, an inner catheter 120, a keyed locking collar 260, and an outer catheter 110. The first actuation line 201 can have a proximal portion and a distal portion. The inner catheter 120 can define a first elongate tubular member 227 having an inner catheter proximal end 124 and an inner catheter distal end 126, and an inner catheter inner surface that defines an inner catheter outer surface 121 and an inner catheter lumen 128. The keyed locking collar 260 can include a keyway 222 (similar to other keyways described elsewhere herein) and can be coupled to the inner catheter 120. The outer catheter 110 can define a second elongate tubular member 217 having an outer catheter proximal end and an outer catheter distal end, and an outer catheter inner surface that defines an outer catheter outer surface 111 and an outer catheter lumen. The outer catheter inner surface can define splines. The splines can extend longitudinally and project radially inwardly into the outer catheter lumen. The outer catheter lumen can be operable to receive the inner catheter 120, and the splines can engage the keyway 222. The splines can define a spline lumen 119 that slidably receives the first actuation line 201. The first actuation line 201 can extend along the outer catheter 110, and the distal portion of the first actuation line 201 can be coupled near the distal end of the outer catheter 110.

[0063] The keyed locking collar 260 can be coupled to the inner catheter 120 as a separate component or as a feature of its shape. In an embodiment, the keyed locking collar 260 can be a separate component that is fixedly or removably coupled to the inner catheter 120. When the keyed locking collar 260 is removably coupled, its position relative to the inner catheter 120 can be adjustable. In an embodiment, the keyed locking collar 260 can be integrally formed with a first elongate tubular member of the inner catheter 120 such that the keyed locking collar 260 becomes a feature of the shape of the inner catheter 120. In this example, integrally formed means manufactured in an integrated fashion. For example, the keyed locking collar 260 can be integrally formed by overmolding, insert molding, skiving, split die, or other similar manufacturing processes. Regardless of whether the keyed locking collar 260 is a separate component or a feature of the shape of the inner catheter 120, the keyed locking collar 260 can radially extend beyond the outer diameter of the inner catheter 120.

[0064] Similar to the key groove 222 described above, in embodiments, the length of the key groove 222, and thus the length of the keyed locking collar 260, can vary from embodiment to embodiment. For example, as described above, the length of the key groove 222 can extend from the proximal end 124 of the inner catheter to the distal end 126 of the inner catheter. In other examples, the length of the key groove 222 can extend toward the distal end 126 of the inner catheter from the proximal end 124 of the inner catheter and terminate near the distal end 126 of the inner catheter. Alternatively, the key groove 222 can extend from the distal end 126 of the inner catheter toward the proximal end 124 of the inner catheter and terminate near the proximal end 124 of the inner catheter. In some embodiments, the key groove 222 can extend intermediate along the length of the inner catheter 120 such that the key groove 222 terminates near both the proximal end 124 and the distal end 126 of the inner catheter. In any case, the length (and other dimensions such as depth) of the key groove 222 can vary among these examples as long as the inner catheter 120 is maintained in a state where it is slidably received (e.g., by splines) within the outer catheter 110 along the length of the key groove 222. Similarly, the length of the keyed locking collar 260 can vary proportionally with the key groove 222, the inner catheter 120, or both. For example, in embodiments, the length of the keyed locking collar 260 can be less than or equal to the length of the inner catheter 120, the length of the key groove 222 can be less than or equal to the length of the keyed locking collar 260, or both can be the case.

[0065] Similar to the case of the first embodiment, by spacing a plurality of splines around the inner surface of the outer catheter, a balanced fit is provided and the orientation of the inner catheter 120 within the outer catheter can be ensured. In an embodiment, the inner surface of the outer catheter can define two splines located approximately 180 degrees apart around the outer catheter, and the outer surface 121 of the inner catheter can define two respective keyways 222 located approximately 180 degrees apart around the inner catheter. In an embodiment, the inner surface of the outer catheter can define three splines located approximately 90 degrees apart around the outer catheter, and the outer surface 121 of the inner catheter can define three respective keyways 222 located approximately 90 degrees apart around the inner catheter. In an embodiment, the inner surface of the outer catheter can define three splines located approximately 120 degrees apart around the outer catheter, and the outer surface 121 of the inner catheter can define three respective keyways 222 located approximately 120 degrees apart around the inner catheter. As described above, the number of splines and keyways 222 has been described from the perspective of having a respective number, but it should be noted that the number of splines and keyways 222 may vary in embodiments without departing from the scope of the present disclosure.

[0066] In an embodiment, the steerable catheter can include a hemostatic seal between the inner surface of the outer catheter and the outer surface 121 of the inner catheter. The hemostatic seal can include an outer silicone tube and an inner film tube and can be created by applying pressure. Such a seal can, for example, minimize blood loss and can easily conform to the profile of a device inserted into the outer catheter while accommodating multiple wires and catheters simultaneously.

[0067] The present disclosure also includes a method 400 for treating a patient, as shown in FIG. 4. In step 410, method 400 can include obtaining a steerable catheter similar to those disclosed elsewhere herein, including catheter system 100. In step 415, it can be determined whether it is desirable to steer the catheter. If so, method 400 can proceed by actuating a first actuation line at step 417 before proceeding to step 420, but if not, method 400 can continue from step 415 to step 420. In step 420, method 400 can include advancing the outer catheter into a body cavity. In step 425, it can be determined whether it is desirable to steer the catheter. If so, method 400 can proceed by actuating a first actuation line at step 427 before proceeding to step 430, but if not, method 400 can continue from step 425 to step 430. In step 430, method 400 includes advancing the inner catheter into the outer catheter, thereby engaging the spline with the keyway. In step 435, it can be determined whether it is desirable to steer the catheter. If so, method 400 can continue by actuating a first actuation line at step 437 before ending, but if not, method 400 can end after step 435.

[0068] As suggested above, it is clear that method 400 can include, optionally at any point during method 400, actuating a first actuation line (e.g., steps 417, 427, and 437). Such actuation can involve manipulation of a portion of the catheter assembly. For example, in an embodiment, method 400 can include actuating the first actuation line, thereby causing movement at the distal end of the outer catheter and navigating the catheter through the patient's body cavity. As described above, these actuations can involve simple or complex movements (e.g., movements around various axes and in multiple planes). In an embodiment, the steerable catheter further includes a handle at the proximal end of the outer catheter. The handle can be operably coupled to the first actuation line such that actuation of the handle causes actuation of the first actuation line. In some such embodiments, actuating the first actuation line includes performing at least one actuation of the handle.

[0069] The present disclosure also includes a method of manufacturing a catheter. The method can include disposing a catheter liner (see, e.g., catheter liner 215 of FIG. 2C) around a keyed mandrel (see, e.g., keyed mandrel 200 of FIG. 2C). In an embodiment, the catheter liner can be a single continuous catheter liner extending from the proximal end of the catheter to the distal end of the catheter. The method can include disposing an actuation line assembly including an actuation line liner and an actuation line therein on at least one keyway of the catheter liner and the keyed mandrel. The method can include securing the actuation line assembly in at least one keyway by braiding a braid (see, e.g., braid 291 of FIG. 2C) over the catheter liner and the actuation line. The method can include disposing a jacket (see, e.g., jacket 293 of FIG. 2C) over the catheter liner, the actuation line assembly, and the braid. And the method can include reflowing the jacket over the catheter liner, the actuation line assembly, and the braid. In an embodiment, the method can include disposing a reinforcement member in at least one keyway of the keyed mandrel. (Aspect) (Aspect 1) A steerable catheter comprising: a first actuation line; an inner catheter having a proximal end of the inner catheter, a distal end of the inner catheter, an outer surface of the inner catheter defining a keyway extending longitudinally, and an inner surface of the inner catheter defining an inner catheter lumen; an outer catheter having a proximal end of the outer catheter, a distal end of the outer catheter, an outer surface of the outer catheter, and an inner surface of the outer catheter defining an outer catheter lumen and a spline projecting radially inwardly into the outer catheter lumen and extending longitudinally; wherein the outer catheter lumen is operable to receive the inner catheter, the spline of the outer catheter is operable to engage the keyway of the inner catheter, and the spline defines a spline lumen operable to receive the first actuation line, the steerable catheter. (Aspect 2) The steerable catheter according to aspect 1, further comprising an outer catheter actuation ring coupled to the distal end of the outer catheter, wherein the first actuation line is coupled to the outer catheter actuation ring. (Aspect 3) The steerable catheter according to aspect 1 or 2, further comprising a second actuation line, wherein the inner catheter defines an inner catheter actuation line lumen from the proximal end of the inner catheter to the distal end of the inner catheter and is operable to receive the second actuation line therethrough, and the second actuation line extends from the proximal end of the inner catheter to the distal end of the inner catheter and is coupled thereto. (Aspect 4) The steerable catheter according to aspect 3, further comprising an inner catheter actuation ring coupled to the distal end of the inner catheter, wherein the second actuation line is coupled to the inner catheter actuation ring. (Aspect 5) The steerable catheter according to any one of aspects 1 to 4, wherein each of the spline and the keyway is parallel to the central axis of the steerable catheter. (Aspect 6) The steerable catheter according to any one of aspects 1 to 5, wherein the inner catheter includes at least one locking collar defining the keyway of the inner catheter. (Aspect 7) The inner catheter includes a first elongate tubular member that defines an outer surface of the inner catheter, and the keyway is defined by the first elongate tubular member, the steerable catheter according to any one of aspects 1-6. (Aspect 8) The inner surface of the outer catheter further defines a plurality of splines, and the outer surface of the inner catheter further defines a plurality of respective keyways, the steerable catheter according to any one of aspects 1-7. (Aspect 9) The inner surface of the outer catheter defines two splines that are located approximately 180 degrees apart around the outer catheter, and the outer surface of the inner catheter further defines two respective keyways that are located 180 degrees apart around the inner catheter, the steerable catheter according to any one of aspects 1-8. (Aspect 10) The inner surface of the outer catheter defines three splines that are located approximately 90 degrees apart around the outer catheter, and the outer surface of the inner catheter further defines three respective keyways that are located approximately 90 degrees apart around the inner catheter, the steerable catheter according to any one of aspects 1-8. (Aspect 11) The inner surface of the outer catheter defines three splines that are located approximately 120 degrees apart around the outer catheter, and the outer surface of the inner catheter further defines three respective keyways that are located approximately 120 degrees apart around the inner catheter, the steerable catheter according to any one of aspects 1-8. (Aspect 12) The steerable catheter includes a deflectable region at or around the distal end of the outer catheter, and the keyway extends along the length of the inner catheter toward the distal end of the inner catheter and terminates near the deflectable region of the outer catheter, the steerable catheter according to any one of aspects 1-11. (Aspect 13) The inner catheter is slidably received within the outer catheter along the length of the keyway, the steerable catheter according to any one of aspects 1-12. (Aspect 14) The steerable catheter further includes a hemostatic seal between the inner surface of the outer catheter and the outer surface of the inner catheter, the steerable catheter according to any one of aspects 1-13. (Aspect 15) A steerable catheter, a first actuation line having a proximal portion and a distal portion, A first elongate tubular member having a proximal end of the inner catheter, a distal end of the inner catheter, and an inner surface of the inner catheter that defines an outer surface of the inner catheter and a lumen of the inner catheter, the inner catheter; A keyed locking collar including a keyway and coupled to the inner catheter; An outer catheter having a proximal end of the outer catheter, a distal end of the outer catheter, an outer surface of the outer catheter, and an inner surface of the outer catheter that defines a lumen of the outer catheter and a spline that extends longitudinally and projects radially inwardly into the lumen of the outer catheter; comprising; The lumen of the outer catheter is operable to receive the inner catheter, the spline of the outer catheter is operable to engage the keyway of the inner catheter, the spline defines a spline lumen operable to receive the first actuation line, the first actuation line extends along the outer catheter, and a distal portion of the first actuation line is coupled near the distal end of the outer catheter, a steerable catheter. (Aspect 16) The steerable catheter according to aspect 15, wherein the keyed locking collar is integrally formed with the first elongate tubular member of the inner catheter. (Aspect 17) The steerable catheter according to aspect 15 or 16, wherein the keyed locking collar extends radially beyond the outer diameter of the inner catheter. (Aspect 18) The steerable catheter according to any one of aspects 15 to 17, wherein the length of the keyed locking collar is shorter than the length of the inner catheter. (Aspect 19) The inner surface of the outer catheter defines two splines located approximately 180 degrees apart around the outer catheter, and the outer surface of the inner catheter further defines two respective keyways located approximately 180 degrees apart around the inner catheter. The steerable catheter according to any one of aspects 15 to 18. (Aspect 20) The inner surface of the outer catheter defines three splines located approximately 90 degrees apart around the outer catheter, and the outer surface of the inner catheter further defines three respective keyways located approximately 90 degrees apart around the inner catheter. The steerable catheter according to aspect 19. (Aspect 21) A method of treating a patient, comprising: obtaining a steerable catheter according to any one of aspects 1 to 20; Advancing the outer catheter into the body cavity, advancing the inner catheter into the outer catheter, thereby engaging the spline with the keyway, and actuating a first actuation line, thereby causing movement at the distal end of the outer catheter, A method comprising: (Aspect 22) The method according to aspect 21, wherein the steerable catheter further comprises a handle at the proximal end of the outer catheter, the handle being operably coupled to the first actuation line such that actuation of the handle causes actuation of the first actuation line, and actuating the first actuation line comprises performing at least one actuation of the handle.

Claims

1. A delivery system, comprising: a first actuation line; an inner catheter having a proximal end of the inner catheter, a distal end of the inner catheter, an outer surface of the inner catheter, and an inner surface of the inner catheter defining an inner catheter lumen; a keyed locking collar defining a keyway and coupled to the outer surface of the inner catheter; an outer catheter having a proximal end of the outer catheter, a distal end of the outer catheter, an outer surface of the outer catheter, and an inner surface of the outer catheter defining an outer catheter lumen and a spline extending longitudinally and projecting radially inwardly into the outer catheter lumen; and the outer catheter lumen is operable to receive the inner catheter, the spline of the outer catheter is operable to engage the keyway of the inner catheter, and the spline defines a spline lumen operable to receive the first actuation line, the delivery system.

2. further comprising an outer catheter actuation ring coupled to the distal end of the outer catheter, the first actuation line being coupled to the outer catheter actuation ring, the delivery system according to claim 1.

3. further comprising a second actuation line, the inner catheter defining an inner catheter actuation line lumen from the proximal end of the inner catheter to the distal end of the inner catheter and being operable to receive the second actuation line therethrough, the second actuation line extending from the proximal end of the inner catheter to the distal end of the inner catheter and being coupled thereto, the delivery system according to claim 1 or 2.

4. further comprising an inner catheter actuation ring coupled to the distal end of the inner catheter, the second actuation line being coupled to the inner catheter actuation ring, the delivery system according to claim 3.

5. The delivery system according to any one of claims 1 to 2, wherein each of the spline and the key groove is parallel to the central axis of the manipulable catheter.

6. The inner catheter includes a first elongate tubular member that defines an outer surface of the inner catheter, and the key groove is defined by the first elongate tubular member. The delivery system according to any one of claims 1 to 2.

7. The inner surface of the outer catheter further defines a plurality of splines, and the outer surface of the inner catheter further defines a plurality of respective key grooves. The delivery system according to any one of claims 1 to 2.

8. The inner surface of the outer catheter defines two splines that are located approximately 180 degrees apart around the outer catheter, and the outer surface of the inner catheter further defines two respective key grooves that are located 180 degrees apart around the inner catheter. The delivery system according to any one of claims 1 to 2.

9. The inner surface of the outer catheter defines three splines that are located approximately 90 degrees apart around the outer catheter, and the outer surface of the inner catheter further defines three respective key grooves that are located approximately 90 degrees apart around the inner catheter. The delivery system according to any one of claims 1 to 2.

10. The inner surface of the outer catheter defines three splines that are located approximately 120 degrees apart around the outer catheter, and the outer surface of the inner catheter further defines three respective key grooves that are located approximately 120 degrees apart around the inner catheter. The delivery system according to any one of claims 1 to 2.

11. The manipulable catheter includes a deflectable member at or around the distal end of the outer catheter, and the key groove extends along the length of the inner catheter towards the distal end of the inner catheter and terminates near the deflectable member of the outer catheter. The delivery system according to any one of claims 1 to 2.

12. The delivery system according to any one of claims 1 to 2, wherein the inner catheter is slidably received within the outer catheter along the length of the key groove.

13. The delivery system according to any one of claims 1 to 2, further comprising a hemostatic seal between the inner surface of the outer catheter and the outer surface of the inner catheter.

14. A delivery system, comprising: a first actuation line having a proximal portion and a distal portion; an inner catheter defining a first elongate tubular member having a proximal end of the inner catheter, a distal end of the inner catheter, an outer surface of the inner catheter, and an inner surface of the inner catheter defining an inner lumen of the inner catheter; a keyed locking collar coupled to the inner catheter and including a key groove; an outer catheter having a proximal end of the outer catheter, a distal end of the outer catheter, an outer surface of the outer catheter, and an inner surface of the outer catheter defining an outer lumen of the outer catheter and a spline projecting radially inwardly into the outer lumen of the outer catheter; and the outer lumen of the outer catheter is operable to receive the inner catheter, the spline of the outer catheter is operable to engage the key groove of the inner catheter, the spline defines a spline lumen operable to receive the first actuation line, the first actuation line extends along the outer catheter, and a distal portion of the first actuation line is coupled near the distal end of the outer catheter.

15. The delivery system according to claim 14, wherein the keyed locking collar extends radially beyond an outer diameter of the inner catheter.

16. The delivery system according to claim 14, wherein a length of the keyed locking collar is shorter than a length of the inner catheter.

17. The inner surface of the outer catheter defines two splines that are located approximately 180 degrees apart around the outer catheter, and the outer surface of the inner catheter further defines two respective key grooves that are located approximately 180 degrees apart around the inner catheter. The delivery system according to claim 14.

18. The inner surface of the outer catheter defines three splines that are located approximately 90 degrees apart around the outer catheter, and the outer surface of the inner catheter further defines three respective key grooves that are located approximately 90 degrees apart around the inner catheter. The delivery system according to claim 17.

19. The position of the keyed locking collar is adjustable along the length of the outer surface of the inner catheter. The delivery system according to claim 1.

20. The keyed locking collar is removably coupled to the inner catheter. The delivery system according to claim 1.

Images