Patent Application
20200121894
The mitral valve controls blood flow from the left atrium to the left ventricle of the heart, preventing blood from flowing backwards from the left ventricle into the left atrium so that it is instead forced through the aorta for distribution throughout the body. A properly functioning mitral valve opens and closes to enable blood flow in one direction. However, in some circumstances the mitral valve is unable to close properly, allowing blood to regurgitate back into the atrium. Such regurgitation can result in shortness of breath, fatigue, heart arrhythmias, and even heart failure.
Mitral valve regurgitation has several causes. Functional mitral valve regurgitation (FMR) is characterized by structurally normal mitral valve leaflets that are nevertheless unable to properly coapt with one another to close properly due to other structural deformations of surrounding heart structures. Other causes of mitral valve regurgitation are related to defects of the mitral valve leaflets, mitral valve annulus, or other mitral valve tissues. In some circumstances, mitral valve regurgitation is a result of infective endocarditis, blunt chest trauma, rheumatic fever, Marfan syndrome, carcinoid syndrome, or congenital defects to the structure of the heart. Other cardiac valves, in particular the tricuspid valve, can similarly fail to properly close, resulting in undesirable regurgitation.
Heart valve regurgitation is often treated by replacing the faulty valve with a replacement valve implant or by repairing the valve through an interventional procedure. However, issues can arise related to deployment and effectiveness of various treatment options. For instance, delivering accessing the targeted treatment site can be challenging. Intravascular delivery of interventional devices can be less invasive relative to open-heart surgery. However, properly routing the necessary equipment through a patient's vasculature, and then properly orienting the interventional components to be able to successfully carry out the procedure, introduces a variety of challenges.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.
The present disclosure describes intravascular delivery systems configured for delivering an interventional device to a targeted anatomical site. In one embodiment, an interventional delivery system includes a handle with one or more controls (e.g., knobs, buttons, dials, etc.), and a delivery catheter coupled to the handle. The delivery catheter has a proximal end and a distal end. The proximal end of the delivery catheter is coupled to the handle. The delivery catheter also includes a distal section which is configured to selectively form a compound curve to enable positioning of the distal end relative to a targeted intravascular treatment site. The compound curve includes a first curve formable at a proximal portion of the distal section and a second curve formable at a distal portion of the distal section. One or more control lines are also operatively coupled to a control of the handle and each control line extends from its respective control to toward the distal end of the delivery catheter. The delivery catheter includes a distal coupler at or near its distal end. The one or more control lines engage with the distal coupler such that tensioning of the one or more control lines changes position of the distal coupler to form or adjust the compound curve.
In some embodiments, the device is configured such that the first curve and the second curve of the compound curve lie in different planes. For example, the respective planes in which the first and second curves lie may be substantially orthogonal to one another. In some embodiments, the first curve is bendable to an angle of about 70 to 120 degrees. In some embodiments, the second curve is bendable to an angle of about 10 to 50 degrees. In some embodiments, the distal section has a length of about 2 to 6 inches, with the first curve being formed in the proximal most 1 to 3 inches, and the second curve being formed in the distal most 1 to 3 inches. In some embodiments, the first curve is pre-curved to an angle of about 30 to about 80 degrees. In some embodiments, the second curve is pre-curved to an angle of about 5 to about 30 degrees.
In some embodiments, the delivery catheter includes an outer jacket of a braided material. The outer jacket at the proximal section may include two layers while the outer jacket at the distal section has a single layer. In some embodiments, the proximal section has a greater hardness rating than the distal section. For example, a catheter wall of the proximal section may have a durometer of about 60D to about 90D, while a catheter wall of the distal section may have a durometer of about 35D to about 55D.
In some embodiments, at least the distal section of the delivery catheter includes a region of preferential bending, where one side of the distal section is formed from a relatively less stiff material and the opposite side of the distal section is formed from a relatively stiffer material.
Some embodiments further include an intermediate coupler disposed at the distal section at a location proximal of the distal coupler. Such embodiments may further include one or more intermediate control lines each operatively coupled to a control of the handle and extending to engage with the intermediate coupler. These intermediate control lines enable manipulation of the intermediate coupler. In such an embodiment, manipulation of the intermediate coupler provides control of the first curve and manipulation of the distal coupler provides control of the second curve.
Additional features and advantages will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of the embodiments disclosed herein. The objects and advantages of the embodiments disclosed herein will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing brief summary and the following detailed description are exemplary and explanatory only and are not restrictive of the embodiments disclosed herein or as claimed.
In order to describe various features and concepts of the present disclosure, a more particular description of certain subject matter will be rendered by reference to specific embodiments which are illustrated in the appended drawings. Understanding that these figures depict just some example embodiments and are not to be considered to be limiting in scope, various embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
The present disclosure relates to intravascular delivery systems having centralized steering. The centralized steering features described herein provide effective routing of the delivery system to a targeted treatment site within a patient's vasculature. In contrast to conventional intravascular delivery systems, embodiments described herein provide effective steering with minimized complexity and a simplified control scheme. For example, many conventional delivery systems require multiple radially nested catheters that must be independently controlled and positioned to provide the steering capabilities necessitated by a particular procedure. Embodiments described herein centralize steering functionality into an integrated elongated member and therefore minimize the number of required system parts, the number of separate delivery steps, and the concomitant risks of mechanical failure and/or human error.
The centralized steering features described herein may also reduce operator error associated with assembly of the intravascular delivery system. For example, an operator may be required to pre-assemble a conventional delivery system by positioning one or more internal guide catheters within an outer guide catheter. If the multiple guide catheters are not properly keyed (axially and rotationally) when they are nested together, the delivery system will be unlikely to function properly during the procedure. In contrast, delivery system embodiments described herein reduce or eliminate the need for such pre-assembly, and therefore minimize the potential for such errors and their associated patient risks.
The targeted treatment site to which a delivery system is delivered may include, for example, a regurgitant/malfunctioning cardiac valve. Delivery systems described herein may be routed to the targeted treatment site to enable delivery of one or more interventional devices through the delivery system and to the treatment site. Such interventional devices may include, for example, a cardiac valve repair device (e.g., such as the MitraClip® available from Abbott Vascular), a replacement valve, a chordae replacement, an annuloplasty device, an occluder, or other interventional tool which may be utilized in an intravascular treatment procedure.
Throughout this disclosure, many examples are described in the context of guiding a delivery system to a mitral valve. One of skill in the art will understand, however, that the described components, features, and principles may also be utilized in other applications. For example, at least some of the embodiments described herein may be utilized for guiding a delivery system to a pulmonary, aortic, or tricuspid valve.
In other implementations, such as for procedures associated with a tricuspid valve, the catheter 104 may be passed through the inferior vena cava 12 into the right atrium 14, where it may then be positioned and used to perform the procedure related to the tricuspid valve. As described above, although many of the examples described herein are directed to the mitral valve, one or more embodiments may be utilized in other cardiac procedures, including those involving the tricuspid valve.
To perform an intravascular maneuver such as that shown in
Although
As shown, a handle 202 is coupled to a delivery catheter 204. The delivery catheter 204 includes a proximal section 208 and a distal section 209. The proximal section 208 and distal section 209 may be attached by a joint 220. The joint 220 may be formed as an adhesive weld, a fitting (external and/or internal), or other suitable fastening structure. In alternative embodiments, the proximal section 208 and distal section 209 may be co-extruded as an integrally joined piece of material. The delivery system 200 may also include a valve 222 for managing fluid flows to and/or from the targeted treatment site. The delivery catheter 204 may also include one or more radiopaque markers 213 for imaging/tracking purposes.
The illustrated handle 202 includes an inlet 224 for providing access to the interior of the delivery catheter 204. The inlet 224 allows an interventional tool to be coupled to the delivery system 200 to be passed, for example, through the delivery catheter 204 to a targeted treatment site. The handle 202 also includes controls 212 and 214 which are operatively coupled to the delivery catheter 204. The controls 212 and 214 are configured to enable an operator to control steering of the delivery catheter 204 through manipulation of the controls 212 and 214. The controls 212 and 214 are shown here as turn knobs. However, it will be understood that other suitable controls, such as buttons, sliders, switches, and the like, may additionally or alternatively be utilized. Additional embodiments of handles and other delivery system components which may be utilized with the delivery catheter embodiments described herein are described in U.S. Patent Application Publication No. 2017/0100250, which is incorporated herein by this reference in its entirety.
The distal section 209 is curvable to enable steering and proper orientation of the distal end 215 relative to a treatment site. The distal section 209 is configured to form a plurality of separate curves such that a resulting compound curve can provide desired positioning and orientation of the distal end 215. As shown, the distal section 209 may be configured to form a first curve 216 at a proximal portion of the distal section 209, and a second curve 218 at a more distal portion of the distal section 209.
The first curve 216 and the second curve 218 preferably lie in different planes, though in some embodiments, they may lie in the same plane. In the illustrated example, the second curve 218 lies on a plane that is substantially orthogonal to the plane on which the first curve 216 lies. For example, the first curve 216 may be configured such that, when the distal section 209 is positioned within a patient's heart (e.g., in the manner illustrated in
In alternative embodiments, the first and/or second curves 216 and 218 may be configured with a different orientation. For example, the first curve 216 may be configured to substantially lie within the sagittal plane while the second curve 218 is configured to substantially lie within the coronal plane when deployed within a patient. In other embodiments, one or more of the first curve 216 or second curve 218 may lie within a plane disposed between the patient's coronal plane and sagittal plane. The relative positions of the first and second curves 216 and 218 may be configured according to particular patient anatomy and/or application needs.
The compound curve formable in the distal section 209 beneficially provides access to targeted intravascular treatment sites, such as the mitral valve. In preferred embodiments, the first curve 216 is configured so as to be bendable to an angle of about 70 to 120 degrees, or about 95 degrees. The second curve 218 may be configured to be bendable to an angle of about 10 to 50 degrees, or about 30 degrees. Compound curves formed using first and second curves within the foregoing angular ranges are particularly useful for accessing a mitral valve treatment site (e.g., through an approach as illustrated in
Exemplary control mechanisms for controlling the curvature of the first curve 216 and second curve 218 are described in more detail below. To facilitate curvature along desired planes and/or in desired directions, the first curve 216 and/or second curve 218 may be pre-curved. As used herein “pre-curved” means that the relevant section of the delivery catheter 204 has a default or natural position, when not subjected to an overriding bending force, which is curved. Such pre-curved sections are not necessarily always curved. For example, while routing the delivery catheter 204 through a patient's vasculature, a pre-curved section may be substantially straightened or otherwise lessened in curvature.
In some embodiments, the first curve 216 is pre-curved to an angle of about 30 to 80 degrees, or about 45 to 65 degrees, or about 55 degrees. In some embodiments, the second curve 218 is pre-curved to an angle of about 5 to 30 degrees, or about 10 to 20 degrees. A distal section 209 having one or more pre-curved sections within the foregoing ranges is particularly useful for providing access to a mitral valve treatment site. For example, where the first curve 216 and/or 218 second curve are pre-curved to a level such as within the foregoing ranges, an operator may readily and effectively route the distal section 209 to the targeted site, and may then augment the curvature(s) to provide a desired orientation with respect to the targeted site. In one example, the pre-curved first section 216 is further curvable by up to about 70 degrees, and/or the second curve is further curvable by up to about 30 degrees.
The delivery catheter 204 may have any length appropriate for accessing the targeted treatment site. Generally, the overall length of the delivery catheter 204 is about 40 to 80 inches, more commonly about 60 inches. The distal section 209 may have a length of about 2 to 6 inches, with the first curve 216 being formed in the proximal most 1 to 3 inches (e.g., about 1.5 inches) of the distal section 209 and the second curve 218 being formed in the distal most 1 to 3 inches (e.g., about 1.5 inches) of the distal section 209.
In the illustrated embodiment, the control lines 226, 228, 230, and 232 are operatively coupled to the handle controls 212 and 214 (see
In this exemplary configuration, manipulation of control 212 adjusts curvature along the plane defined by control lines 226 and 228, while manipulation of control 214 adjusts curvature along the plane defined by control lines 230 and 232. The plane defined by control lines 226 and 228 may be the plane on which the first curve 216 lies, while the plane defined by control lines 230 and 232 may be the plane on which the second curve 218 lies.
Although the illustrated delivery systems are shown as having two handle controls, it will be understood that other numbers of controls may be utilized in alternative embodiments. Some embodiments may include one or more additional controls. In one example, each control line in a pair of corresponding, circumferentially opposed control lines may be operatively coupled to a separate control at the handle 202. For example, control line 226 and 228 may be coupled to separate controls at the handle 202 rather than to the same control.
The coupler 210 is shown in the illustrated embodiment as a ring structure configured to receive and engage with the control lines 226, 228, 230, and 232. In alternative embodiments, the coupler 210 may be configured as a band, fitting, or other suitable structure for receiving and engaging with control lines 226, 228, 230, and 232. In other embodiments, one or more control lines may be affixed to the catheter using an adhesive.
In the illustrated embodiment, each control line 226, 228, 230, and 232 passes through the catheter to the coupler 210 and then loop back to pass back toward the handle 202. Such a double-strand configuration provides for effective tensioning of the control lines with reduced risk of line breakage or detachment. Alternatively, one or more control lines may be welded to the coupler 210 and need not necessarily loop back toward the handle 202. Additional embodiments of ring structures which may be utilized as coupler 210 or as other coupler embodiments taught herein are described in U.S. Patent Application Publication No. 2016/0367787, which is incorporated herein by this reference in its entirety.
Although all of the control lines 226, 228, 230, and 232 terminate at the same coupler 210, the curves 216 and 218 may be primarily formed at different regions of the distal section 209 as a result of pre-curvature and/or preferential bending features at the different regions. For example, pre-curvature and/or preferential bending features of the delivery catheter 204 (e.g., particularly at the distal section 209) may promote curvature associated with manipulation of a first pair of control wires to occur primarily at the first curve 216, and curvature associated with manipulation of a second pair of control wires to occur primarily further distally at the second curve 218.
Once positioned at a desired location relative to the targeted mitral valve 20, one or more interventional devices may be delivered through the delivery catheter 204 in order to perform the desired repair or replacement procedure. Further adjustment of the delivery catheter position may also be done intra-procedurally as desired.
In some embodiments, the catheter wall 234 is formed from a medical-grade polymer such as polyether block amide (e.g., Pebax®), polyurethane, nylon, polyethylene, polyimide, polyethylene terephthalate (PET), or polyetheretherketone (PEEK). Preferably, the catheter wall 234 of the proximal section 208 has a hardness of greater than about 35D (e.g., using the Shore D scale) and up to about 90D. For example, in some embodiments the catheter wall 234 may be formed from Pebax® having a durometer of above 60D to about 75D. In some embodiments, the catheter wall 234 may be formed from a nylon material (e.g., Nylon-12) having a durometer of about 80D to 90D.
The components of the proximal section 208 are configured to provide effective column strength and torque transmissibility. Although the proximal section 208 may include pre-shaping, in preferred embodiments the proximal section 208 omits pre-shaping. The proximal section 208 is preferably instead configured to provide column strength and torque transmissibility so that the distal section 209 can be effectively delivered to the targeted treatment site.
The catheter wall 234 may include one or more wall lumens 236. In the illustrated embodiment, four pairs of wall lumens 236 are disposed at approximately 90 degree increments around the cross-section of the proximal section 208. Each pair is configured to channel a control line from the handle 202 to the coupler 210 (see
The illustrated embodiment also includes a set of keyways 238. One or more of such keyways 238 may be included for rotational keying of the proximal section 208 with an interventional device passed through the inner lumen. For example, the interventional device may include one or more keys or grooves configured to match the keyways 238 to rotationally align the interventional tool with the proximal section 208. Alternative embodiments additionally or alternatively use other keying features. For example, the catheter wall 234 may include one or more keys, tabs, or grooves configured to match with a corresponding keyway of the interventional device.
The catheter wall 244 of the distal section 209 may be formed from the same material as the catheter wall 234 of the proximal section 208 or may be formed from a different material. For example, the catheter wall 234 and the catheter wall 244 may both be formed from Pebax®, with the Pebax® of the catheter wall 234 being a harder grade than the Pebax® of the catheter wall 244. In another example, the catheter wall 234 is formed from Nylon-12 and the catheter wall 244 is formed from a relatively softer Pebax®.
As described above, the distal section 209 may be formed with one or more regions of pre-curvature and/or preferential bending. In some embodiments, such a region is formed by co-extruding the catheter wall 244 with materials of differing stiffness. For example, one side (e.g., about 50%) of the extruded catheter wall 244 may be extruded or otherwise formed with a material of relatively higher stiffness while the opposite side is extruded or otherwise formed with a material of relatively lower stiffness. In some embodiments, a relatively harder grade of Pebax® or other suitable material (e.g., about 45D to 55D) is utilized for the higher stiffness side and a softer grade of Pebax® or other suitable material (e.g., about 35D to 45D) is utilized for the lower stiffness side. The side formed of the lower stiffness material may then function as a direction of preferred bending. Heat setting or other suitable method may be utilized to set a pre-shaped curve.
The jacket 250 of the distal section 209 may have a lower pic count and/or less layers as compared to the jacket 240 of the proximal section 208. For example, the jacket 240 may utilize a single layer of braided material having a pic count of about 10 to 30.
The components of the distal section 209 are configured to provide effective steerability to the distal section 209, while the proximal section 208 is generally configured to provide effective torquability and column strength. In combination, the proximal section 208 and distal section 209 therefore provide, as a single integrated catheter, effective routing to a targeted treatment site and effective steerability and maneuverability of the distal tip relative to the targeted treatment site
As shown in
The distal section 309 of the illustrated embodiment includes a distal coupler 310 disposed at the distal end of the delivery catheter 304. The distal coupler 310 may be configured in a manner similar to the coupler 210 of delivery system 200 as described above. In addition to the distal coupler 310, the illustrated delivery catheter 304 further includes an intermediate coupler 311 disposed a distance proximal of the distal coupler 310. The intermediate coupler 311 and distal coupler 310 function to enable control of the curvatures of the first curve 316 and second curve 318, respectively.
In the illustrated embodiment, the intermediate coupler 311 is positioned such that manipulation of control lines 330 and 332 moves the intermediate coupler 311 and thereby adjusts the first curve 316. Similarly, the distal coupler 310 is positioned such that manipulation of control lines 326 and 328 moves the distal coupler 310 and thereby adjusts the second curve 318.
In the illustrated embodiment, control lines 326 and 328 are positioned circumferentially opposite one another and control lines 330 and 332 are positioned circumferentially opposite one another. Each pair of control lines may respectively be coupled to a different control 312 and 314, such that one control functions to adjust the intermediate coupler 311 and first curve 316 (e.g., along a plane defined by control lines 330 and 332) while the other control functions to adjust the distal coupler 310 and second curve 318 (e.g., along a plane defined by control lines 326 and 328). The plane on which the first curve 316 lies may be orthogonal to the plane on which the second curve 318 lies. Alternative embodiments may position one or more control lines differently so as to define different planes of curvature for the first curve 316 and/or second curve 318.
The proximal section 308 and distal section 309 of the illustrated embodiment may have cross-sectional configurations, materials, and pre-curvature and/or preferential bending features similar to those of corresponding components of delivery system 200, such as shown in
The articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements in the preceding descriptions. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Numbers, percentages, ratios, or other values stated herein are intended to include that value, and also other values that are “about” or “approximately” the stated value, as would be appreciated by one of ordinary skill in the art encompassed by embodiments of the present disclosure. A stated value should therefore be interpreted broadly enough to encompass values that are at least close enough to the stated value to perform a desired function or achieve a desired result. The stated values include at least the variation to be expected in a suitable manufacturing or production process, and may include values that are within 5%, within 1%, within 0.1%, or within 0.01% of a stated value.
Elements described in relation to any embodiment depicted and/or described herein may be substituted for or combined with elements described in relation to any other embodiment depicted and/or described herein. For example, any of the components or features described in relation to delivery system 200 may be substituted for or combined with any of the components or features described in relation to delivery system 300, and vice versa.
This application is a divisional of U.S. patent application Ser. No. 15/662,084, filed Jul. 27, 2017, the entire contents of which are incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15662084 | Jul 2017 | US |
| Child | 16720845 | US |
