Patent ID: 12232743

DETAILED DESCRIPTION

Example embodiments according to the present disclosure are described and illustrated below to encompass devices, methods, and techniques relating to medical devices and procedures. Of course, it will be apparent to those of ordinary skill in the art that the embodiments discussed below are examples and may be reconfigured without departing from the scope and spirit of the present disclosure. It is also to be understood that variations of the example embodiments contemplated by one of ordinary skill in the art shall concurrently comprise part of this disclosure. However, for clarity and precision, the example embodiments as discussed below may include optional steps, methods, and features that one of ordinary skill should recognize as not being a requisite to fall within the scope of the present disclosure.

The present disclosure includes, among other things, medical instruments and devices, and, more specifically, exclusion devices for anatomical structures, and related instruments and related methods. Some example embodiments according to at least some aspects of the present disclosure may be useful as left atrial appendage occlusion clips for exclusion of a patient's left atrial appendage, such as to reduce the patient's atrial fibrillation burden and/or to reduce the patient's risk of stroke. It is to be understood, however, that various example embodiments according to the present disclosure may be utilized in connection with anatomical structures other than left atrial appendages. The following description begins with an overview of an example exclusion device and application instrument, followed by detailed descriptions of specific aspects of various example embodiments.

Generally, some example exclusion devices according to at least some aspects of the present disclosure may be delivered to a surgical site in a closed configuration using an application instrument. The application instrument may be actuated to reconfigure the exclusion device into an open configuration. The application instrument may be manipulated to position the exclusion device around an anatomical structure. The application instrument may be actuated to reconfigure the exclusion device into a closed configuration to at least partially occlude the anatomical structure. The application instrument may be actuated to detach the exclusion device, and the application instrument may be withdrawn from the surgical site.

FIG.1is an elevation view of an example exclusion device100for an anatomical structure in a closed configuration, in accordance with at least some aspects of the present disclosure. This example exclusion device100is generally in the form of an occlusion clip including a first clamping portion102and an opposing second clamping portion104. The first clamping portion102and the second clamping portion104are biased in a closing direction (e.g., generally towards each other).

The illustrated exclusion device100includes a cover200, which at least partially sheaths one or both of the clamping portions102,104. This example cover200is constructed from a textile, which may initiate the body's healing response and/or promote tissue ingrowth. In the illustrated embodiment, the cover200is generally tubular and covers each of the clamping portions102,104individually in a generally toroidal manner. In some example embodiments, the cover200may substantially enclose the other components of the exclusion device100.

Some example exclusion devices100according to at least some aspects of the present disclosure may be configured so that, in the closed configuration, the exclusion device100envelope may be less than about 5 mm laterally. Accordingly, some example embodiments may be configured to fit through relatively small ports, such as a 5 mm trocar. The present disclosure contemplates that some other implantable exclusion devices may have a device envelop that is about 12 mm laterally. See, for example, some devices described in U.S. Pat. No. 10,166,024, issued Jan. 1, 2019, which is incorporated by reference. Accordingly, some example exclusion devices100according to at least some aspects of the present disclosure may be advantageous when used in connection with minimally invasive surgical approaches. Additionally, some example exclusion devices100according to at least some aspects of the present disclosure may tend to obstruct a surgeon's view to a lesser extent than relatively larger exclusion devices, thus allowing the surgeon to better visualize nearby structures, such as nearby structures which might potentially interfere with a procedure.

FIG.2is a perspective view of the exclusion device100ofFIG.1in the closed configuration and without the cover200, andFIG.3is a perspective view of the exclusion device100ofFIG.1in the open configuration and without the cover200, all in accordance with at least some aspects of the present disclosure. Referring toFIGS.1-3, in this example exclusion device100, the first clamping portion102includes a first beam106and the second clamping portion104includes a second beam108. The first beam106and the second beam108are coupled together by a generally U-shaped first spring110and a generally U-shaped second spring112. Generally, the first spring110is coupled to the beams106,108inward from their respective first ends114,116. Similarly, the second spring112is coupled to the beams106,108inward from their respective second ends118,120.

In this example embodiment, the beams106,108include opposed clamping surfaces122,124, which are configured to engage an anatomical structure10positioned therebetween. For example, the exclusion device100may be positioned to at least partially occlude an anatomical structure10including a left atrial appendage by clamping the LAA between the clamping surfaces122,124of the clamping portions102,104. Some embodiments may be configured to accommodate LAAs from about 24 mm to about 50 mm wide, for example.

In the illustrated embodiment, the springs110,112are arranged to bias the first beam106and the second beam108towards each other (e.g., in a closing direction). In this embodiment, the first clamping portion102and the second clamping portion104are substantially in contact in the closed configuration when the exclusion device100is empty. Specifically, the clamping surfaces122,124(which may be covered by the cover200) may be substantially in contact with one another in the closed configuration when the exclusion device100is empty. Some alternative example embodiments may be configured so that the springs110,112bias the beams106,108in the closing direction but do not draw the clamping portions fully into contact with each other in the closed configuration when the exclusion device100is empty. Thus, in some such embodiments, even with no other structure interposing the clamping portions102,104, a gap may exist between the clamping portions102,104in the closed configuration. As used herein, “closed configuration” may refer to a configuration in which an exclusion device100is substantially independently maintaining its clamping portions102,104in a configuration closer together than the fully open configuration, whether or not the clamping portions are in contact with each other and whether or not any other object (e.g., anatomical structure) interposes the clamping portions. In the illustrated embodiment, in the fully open configuration, the beams106,108are spaced apart about 14 mm.

In the illustrated embodiment, the springs110,112are selected so that the clamping portions102,104are spaced apart when in the closed configuration with an anatomical structure10interposing the clamping surfaces122,124. As a result, the anatomical structure10may be substantially occluded, but is generally not severed.

FIG.4is an elevation view of an example exclusion device100application instrument300with the exclusion device100ofFIG.1in a closed configuration andFIG.5is an elevation view of the example exclusion device100application instrument300ofFIG.4with the exclusion device100ofFIG.1in an open configuration, all in accordance with at least some aspects of the present disclosure. This example application instrument300includes a generally proximal handle portion302, an elongated, malleable shaft304extending distally from the handle portion302, and an end effector306disposed distally on the shaft304. As used herein, “distal” may refer to a direction generally away from an operator of a system or device (e.g., a surgeon), such as toward the distant-most end of a device that may be inserted into a patient's body. As used herein, “proximal” may refer to a direction generally toward an operator of a system or device (e.g., a surgeon), such as away from the distant-most end of a device that may be inserted into a patient's body.

In the illustrated embodiment, the exclusion device100is releasably secured to the end effector306application instrument300. The end effector306is arranged to reconfigure the exclusion device100between open and closed configurations and to release the exclusion device100based on operation of one or more actuators308,310on the handle portion302by the user. For example, the handle portion302and/or the actuators308,310may be generally similar in construction and operation to those described in U.S. Patent Application Publication No. 2019/0142428, published on May 16, 2019, which is incorporated by reference herein in its entirety.

In the illustrated embodiment, the end effector306includes a distal, stationary jaw312and a proximal, movable jaw314. Each of the clamping portions102,104of the exclusion device100is releasably coupled to a respective one of the jaws312,314. Operation of the first actuator308causes the end effector306to reconfigure the exclusion device100between the open and closed configurations by moving the movable jaw314away from and towards the stationary jaw312. In some example embodiments, the first actuator308may be operable to open the exclusion device100, and the closing-biased nature of the exclusion device100may be operative to close the exclusion device100as the first actuator308is released by the user. In some example embodiments, the end effector306may be configured for substantially parallel opening of the first clamping portion102and second clamping portion104of the exclusion device100. Operation of the second actuator310may cause the end effector306to release (e.g., deploy) the exclusion device100by detaching the clamping portions102,104from the jaws312,314. For example, the clamping portions102,104may be releasably secured to the respective jaws312,314by respective sutures316,318, which may be released by operation of the second actuator310. Example mechanisms arranged to deploy an exclusion device from an end effector are described in U.S. Patent Application Publication No. 2018/0036007, published Feb. 8, 2018, which is incorporated by reference. In some example embodiments, the sutures316,318(or other attachment elements) may be positioned generally centered longitudinally along the clamping portions102,104. The actuators308,310may be operatively coupled to the end effector306by one or more mechanical linkages, such as one or more rods and/or cables.

The present disclosure contemplates that covers for implantable exclusion devices may promote tissue ingrowth and/or may provide barriers between relatively hard components of the devices (e.g., beams) and adjacent tissues (e.g., the heart). Some implantable exclusion devices may be configured so that the cover generally does not move relative to the structural components. That is, the cover may remain substantially in place on the structural components and/or may not stretch as the exclusion device is reconfigured. Other implantable exclusion devices, such as the exclusion device100, may include biocompatible covers200that are configured to move (e.g., stretch) relative to underlying components.

FIG.6is a longitudinal cross section view of the exclusion device100ofFIG.1in the closed configuration and without the cover200, andFIGS.7and8are detailed longitudinal cross section views of a portion of the first beam106proximate the second end118, all in accordance with at least some aspects of the present disclosure. The following description focuses generally on features of the first beam106proximate its second end118. However, it is to be understood that the first end114of the first beam106may be substantially similar (e.g., in a mirror-image manner) to the second end118. Further, the second beam108may be substantially similar (e.g., in an inverted manner) to the first beam106. Accordingly, the description of features of the first beam106proximate its second end118may apply to other portions of the example exclusion device100, but is not repeated for brevity.

Referring toFIGS.2,3, and6-8, in the illustrated embodiment, the second spring112is generally U-shaped and includes a first end portion126and a second end portion128generally opposite a connecting portion130. At least a portion of the first end portion126is received within a generally longitudinally oriented spring cavity132formed in the first beam106. The spring cavity132is open towards the second end118of the first beam106and receives the first end portion126of the second spring112from that direction.

Referring toFIGS.2,3, and7, in the illustrated embodiment, when the exclusion device100is reconfigured from the closed position (FIGS.2and7) to the open configuration (FIG.3), the first end portion126of the second spring112remains secured within the cavity132of the first beam106. The portion of the second spring112proximate the cavity132bends from a generally longitudinal, slightly outward orientation (FIGS.2and7) to a markedly inward orientation (FIG.3). In some example embodiments, the first beam106may include a spring stress reduction feature proximate the cavity132. For example, in the illustrated embodiment, the beam106includes an outwardly facing, rounded spring contact surface134configured to reduce stress concentrations in the second spring112when the exclusion device100is in the open configuration. In some example embodiments, the spring contact surface134may also facilitate assembly of the exclusion device100, such as by funneling the first end portion126of the second spring112into the cavity132of the first beam106.

Referring toFIGS.2,3,6, and7, in the illustrated embodiment, at least a portion of the beam106between the cavity132and the second end118may include a longitudinal slot136extending generally outward from the clamping surface122. At least a portion of the second spring112is slidably received within the slot136. Generally, the slot136may aid in maintaining a generally coplanar alignment of the first beam106, the second spring112, and the second beam108. Accordingly, the second spring112and the slot136may cooperate to reduce the likelihood of the beams106,108coming substantially out of alignment (e.g., out of plane), such as during opening and/or closing of the exclusion device100.

Referring toFIGS.2,3,6, and8, in some example embodiments, the first beam106and/or the second spring112may be plastically deformed to secure the second spring112to the first beam106. In the illustrated embodiment, a tool such as a punch138may be used crimp the beam106and the first portion126of the second spring112to secure them together.

Referring toFIG.8, in this example embodiment, the outer wall140of the first beam106(e.g., generally opposite the clamping surface122) at a crimping location proximate the cavity132is thinner than adjacent portions of the beam106. For example, the outer wall140may include an outwardly facing recess142, which may be configured to receive the punch138therein. In some example embodiments, the outwardly facing recess142may act as a registration location for the punch138and/or may at least partially define the thinner portion of outer wall140.

Referring still toFIG.8, in this example embodiment, the inner wall144of the first beam106(e.g., generally towards the clamping surface122) may include a cavity recess146within the cavity132. This cavity recess146may be generally aligned with the desired crimping motion of the punch138. In some example embodiments, the cavity recess146may provide space to allow deformation of the outer wall140of the first beam106and/or the first end portion126of the second spring112past a desired permanent deformation in order to achieve the desired permanent deformation. That is, the cavity recess146may provide relief to accommodate elastic deformation of the second spring112during the crimping operation, such as due to the relatively high yield strength of the second spring112material. In some example embodiments, at least a portion of the first end portion126of the second spring112may remain at least partially within the cavity recess146after the crimping operation. The example cavity recess146shown inFIG.8is generally in the form of partial sphere, which may be formed, for example, when the first beam106is 3D printed. In alternative example embodiments, the cavity recess146may have different shapes. For example, the cavity recess146may generally have the form of a through hole, such as in a metal injection molded first beam106.

Generally, during an example crimping operation, the punch138may deform at least a portion of the outer wall140of the first beam106at least partially into the cavity132, which may deform at least a portion of the first end portion126of the second spring112at least partially into the recess146. Depending on the extent of the deformation, the strength of the materials comprising the first beam106and the second spring112, etc., at least a portion of the outer wall140of the first beam106and/or at least a portion of the first end portion126of the second spring112may be plastically deformed to form the crimp connection between the first beam106and the second spring112. That is, the crimp connection may include a plastically deformed portion of the second spring112engaged with a plastically deformed portion of the first beam106, for example.

FIG.9is a lateral cross section view of an example beam106of the exclusion device100ofFIG.1, according to at least some aspects of the present disclosure. In the illustrated embodiment, the beam height148is about 2 mm and the beam width150is about 2.5 mm. In some example embodiments, the clamping surface122may be configured to provide a generally even pressure on the anatomical structure10(FIG.3) across the width of the clamping surface122. Various clamping surface122shapes (e.g., profiles) may be utilized to achieve a desired tradeoff between increasing tissue surface contact area and/or reducing tissue stretching and/or trauma when the exclusion device100is closed on the anatomical structure10. Example curvatures of the clamping surface122may include, but are not limited to, curves generally in the form of the curvature of the surface of a water droplet, a natural logarithmic decay curve, a half round shape (e.g., constant radius), oval, parabolic, and/or generally flat.

FIGS.10-12are perspective views of alternative example clamping surface122gripping features152,154,156, according to at least some aspects of the present disclosure.FIG.10illustrates a clamping surface122including an example rough surface finish152. As used herein, “rough surface finish” may refer to a surface that is generally uniformly rough at a fine scale, but which lacks readily individually discernable surface features and/or which presents a generally smooth surface curvature at a larger scale.FIG.11illustrates a clamping surface122including gripping features comprising protrusions154. The protrusions154may extend generally orthogonally from the clamping surface122. The protrusions154may be generally conically and/or cylindrically shaped, for example. In various example embodiments, the protrusions154may be arranged in a regular pattern (e.g., in clusters or lines) and/or generally randomly and/or generally uniformly distributed. For example, a grit media may be embedded generally randomly into the clamping surface122. In alternative example embodiments, gripping features comprising holes or recesses may be similarly arranged.FIG.12illustrates a clamping surface122including gripping features comprising ridges156. In this example embodiment, the ridges156are oriented generally longitudinally along the beam106(FIG.2).

Generally, in some example embodiments, the gripping features152,154,156may be configured to aide in anchoring the exclusion device100and cover200after the exclusion device is placed on the anatomical structure10. For example, the gripping features152,154,156may increase the friction and/or gripping strength between the beams106,108and the cover200and/or between the beams106,108and the anatomical structure10. Accordingly, the gripping features152,154,156may reduce the likelihood of the cover200moving relative to the beams106,108(e.g., circumferentially rolling around the beams106,108) and/or may reduce the likelihood of the exclusion device100moving relative to the anatomical structure10. Various gripping features152,154,156may be formed by 3D printing and/or other manufacturing processes.

Referring toFIGS.2,3,5,7, and8, in some example embodiments, the beams106,108may be configured to have sufficient bending strength to allow the exclusion device100to be releasably secured to the respective jaws312,314of the end effector306of the application instrument300using one attachment point for each clamping portion102,104. For example, the beams106,108may be configured to have sufficient bending strength to allow the exclusion device100to be releasably coupled to the jaws312,314by the individual sutures316,318(or other attachment elements), which may be positioned generally centered longitudinally along the clamping portions102,104. In particular, the beams106,108may be designed so that the beam moment of inertia provides sufficient strength and/or limited deflection when subject to generally longitudinally centrally applied opening forces sufficient to overcome the closing forces exerted by the springs110,112.

FIG.13is a detailed perspective view of a portion of the first beam106proximate the second end118, according to at least some aspects of the present disclosure. Referring toFIGS.1,6,7, and13, some example beams106,108may include one or more portions configured to act as mandrels for welding operations involving the cover200. For example, in the illustrated embodiment, the first beam106includes outwardly facing surfaces158,160, which may be configured to cooperate with externally applied ultrasonic and/or heat welding apparatus for joining portions of the cover200. In some example embodiments, the outwardly facing surfaces158,160may be generally solid (e.g., without substantial recesses or voids) and/or may be generally flat.

In some example embodiments, the beams106,108may be constructed from one or more metals and/or metal alloys, such as titanium and/or titanium alloys. For example, the beams106,108may be constructed from grade 5 and/or grade 23 titanium. Alternative example embodiments may be constructed of other titanium alloys, such as grade 2. Further alternative example embodiments may be constructed from other materials, such as plastics, stainless steel, magnesium, iron, other titanium grades, nitinol, or other biocompatible materials having desired material properties.

Some example beams106,108may be constructed by 3D printing. Alternative embodiments may be constructed by metal injection molding, chemical etching, and/or stamping. Some example embodiments may be machined.

In some example embodiments, the beams106,108may include features configured to promote tissue in growth after placement of the exclusion device100. For example, referring toFIG.6, the beams106,108may include one or more holes or cavities162arranged to facilitate tissue in growth. In some example embodiments, the beams106,108may be formed from a generally porous material to facilitate tissue ingrowth. For example, the beams106,108may be 3D printed in a manner that forms them to have a generally porous nature.

Some example methods of making an exclusion device100for an anatomical structure10according to at least some aspects of the present disclosure may include one or more of the following operations. A first beam106, a second beam108, and a first spring110may be obtained. Obtaining the first beam106may include at least one of 3D printing the first beam106, metal injection molding the first beam106, and machining the first beam106. The first beam106may include a generally longitudinally oriented spring cavity132and/or the first spring110may be generally U-shaped and/or may include a first end portion126and a second end portion126generally opposite from a connecting portion130.

In some example embodiments, the first spring110first end portion126may be inserted into the first beam106spring cavity132. Inserting the first spring110first end portion126into the first beam106spring cavity132may include positioning the first spring110first end portion126through a generally longitudinal slot136between the spring cavity132and an end118of the first beam106. The slot136may be configured to cooperate with the spring110to reduce the likelihood of the first beam106and the second beam108from moving out of a generally coplanar alignment.

The first beam106and the first spring110may be crimped to secure the first spring110first end portion126in the first beam106spring cavity132. Crimping the first beam106and the first spring110may include plastically deforming a portion of the first beam106and/or a portion of the first spring110. The first beam106may include an outer wall140at least partially defining the spring cavity132. The outer wall140may be disposed generally opposite a clamping surface122of the first beam106. The outer wall140may include an outwardly facing recess142. Crimping the first beam106and the first spring110may include receiving a tool138at least partially within the outwardly facing recess142of the outer wall140. The first beam106may include an inner wall144at least partially defining the spring cavity132. The inner wall144may be disposed generally towards a clamping surface122of the first beam106. The inner wall144may include a cavity recess146within the spring cavity132. Crimping the first beam106and the first spring110may include deforming at least a portion of the first end portion126of the first spring110into the cavity recess146. Similar operations for assembling and securing components may be performed for other connections between beams and springs (e.g., crimp connections), and repeated description is omitted for brevity.

Some example methods of occluding an anatomical structure10according to at least some aspects of the present disclosure may include one or more of the following operations. An exclusion device may be delivered to a surgical site in a closed configuration. The exclusion device may include a first beam, a second beam, at least one spring operatively coupled to the first beam and the second beam to exert a closing force on the first beam and the second beam, the at least one spring operatively coupled to the first beam by a crimp connection. The exclusion device may be reconfigured from the closed configuration to an open configuration. The exclusion device may be positioned around an anatomical structure. The exclusion device may be reconfigured into the closed configuration to at least partially occlude the anatomical structure.

Reconfiguring the exclusion device into the closed configuration may include allowing the closing force exerted by the at least one spring to move the first beam and the second beam into the closed configuration. The method may further include detaching the exclusion device from an application instrument, withdrawing the application instrument, and/or maintaining the exclusion device in the closed configuration using the at least one spring.

The exclusion device may include a left atrial appendage occlusion clip. Positioning the exclusion device around the anatomical structure may include positioning the left atrial appendage occlusion clip around a left atrial appendage. At least partially occluding the anatomical structure may include at least partially occluding the left atrial appendage.

FIG.14is detailed elevation view of an example first spring110according to at least some aspects of the present disclosure. Although the following description focuses on the first spring110of the exclusion device100(FIG.1), the second spring112may be substantially similar to the first spring110. Accordingly, the following description may also generally apply to the second spring112. For the avoidance of doubt,FIG.13illustrates the example first spring110in a relaxed condition (e.g., without any externally applied forces). Dimensions, which are merely examples, are indicated in inches.

In the illustrated embodiment, the first spring110is generally U-shaped and includes a first end portion164and a second end portion166generally opposite a connecting portion168. Interposing the connecting portion168and the first end portion164is a first reverse bend portion170. Interposing the connecting portion168and the second end portion166is a second reverse bend portion172. Between the connecting portion and the reverse bend portions170,172, the first spring110may be generally converging. Between the reverse bend portions170,172and the end portions164,166, the first spring110may be generally diverging. In the illustrated embodiment, when the exclusion device100is assembled, the reverse bend portions170,172may be configured to provide a spring pre-load (e.g., a closed-bias pre-load).

In some example embodiments, the first spring110may be substantially coplanar. That is, other than the thickness of the spring material forming the first spring110, the spring may be substantially two-dimensional. Accordingly, the first spring110may exert forces substantially in only two dimensions, and there is generally no shearing action when the first spring110returns to its relaxed condition. In alternative embodiments, the first spring110may be non-coplanar. For example, a portion of the first spring110may cross over another portion of the first spring110. In some such embodiments, the exclusion device100may be configured to provide additional stability due to the spring force in the third dimension.

In operation, some example first springs110may act as a combination of spring types. For example, the generally rounded connecting portion168of the first spring110may act generally as a torsion spring. The torsional moment associated with this portion of the first spring110is indicated by arrow174. The elongated leg portions176,178(e.g., the portions extending from the connecting portion168and including the first end portion164and the second end portion166) may act as cantilever springs. The bending moments associated with these portions of the first spring110are indicated by arrows180,182.

The first spring110may include a first bend in the connecting portion168. Each side of the first bend may be at an angle186relative to a reference line184. For example, angle186may be about 98 degrees. The first spring110may include a second bend in the first reverse bend portion170. The second bend may be at an angle188relative to the portion proximate the first bend. For example, angle188may be about 23 degrees. The second reverse bend portion172may be generally similar, but opposite in direction. Between the bends, the first spring110may be generally straight.

FIG.15is a perspective view of an alternative example exclusion device500, in the closed configuration and without a cover, in accordance with at least some aspects of the present disclosure. Exclusion device500is generally similar to the exclusion device100described above, and repeated description of components in common is omitted for brevity.

In the illustrated embodiment, the exclusion device includes a first beam502and a second beam504. Each beam502,504has a respective first end506,508and second end510,512. The first beam502and the second beam504are coupled together by generally U-shaped springs514,516,518,520. The first spring514and the second spring516are coupled to the beams502,504inward from their respective first ends506,508. The third spring518and the fourth spring520are coupled to the beams502,504inward from their respective second ends510,512. Accordingly, each end506,508,510,512of each beam502,504is coupled to the other beam502,504by two springs514,516,518,520, for a total of four springs514,516,518,520coupling the beams502,504together.

In the illustrated embodiment, the springs514,516,518,520are coupled to the beams502,504by pivots522,524,526,528, which extend laterally through the beams502,504and/or are rotatable relative to the beams502,504. Specifically, the first spring514and the second spring516are coupled to the first beam502by the first pivot522and to the second beam504by the second pivot524. The third spring518and the fourth spring520are coupled to the first beam502by the third pivot526and to the second beam504by the fourth pivot528. In some alternative example embodiments, the springs514,516,518,520may be coupled to the beams502,504by posts which are generally similar to the pivots522,524,526,528, but which are secured against rotation relative to the beams502,504. In some such embodiments, the beams502,504may be less likely to move out of alignment (e.g., parallelograming).

Generally, the four-spring exclusion device500ofFIG.15may allow the use of smaller springs, subject to lower stresses, than the two-spring exclusion device100ofFIG.2to achieve similar acceptable clamping forces. Additionally, in some example embodiments, some four-spring exclusion devices500may utilize simpler beam geometry as compared to the two-spring exclusion device100. Accordingly, some beams502,504of four-spring exclusion devices500may be manufactured using stamping, laser cutting, water jet cutting, and/or machining processes.

In some example embodiments, springs may be constructed from Nitinol. The present disclosure contemplates that some Nitinol alloys may have superelastic properties, which may be advantageous for some spring applications. The present disclosure contemplates that some springs constructed from some Nitinol alloys may exert a higher force when opening than when closing. That is, the unloading force may be less than the loading force.

The present disclosure contemplates that some springs constructed from some Nitinol alloys may exert greater forces at typical body temperatures (e.g., about 37 C) than at typical room temperatures (e.g., about 20 C). For example, in the illustrated embodiments, the springs exert about 60% more force at typical body temperatures than at typical room temperatures. As a result, some example exclusion devices may exert larger forces on the anatomical structure10after implantation (e.g., at about body temperature) than the force applied by the application instrument300to open the exclusion device prior to implantation (e.g., at about room temperature).

The present disclosure contemplates that the strength of Nitinol may degrade when it is cycled, particularly when it is cycled close to the yield strength. Accordingly, the springs110,112,514,516,518,520may be designed so that an expected number reconfigurations between the closed configuration and the open configuration (e.g., 100 cycles) will not reduce the strength of the springs110,112,514,516,518,520below a desired specification. Further, the present disclosure contemplates that Nitinol strength degradation due to cycling may be reduced with resting time. For example, some Nitinol components may recover approximately 90% of full strength after several days. Accordingly, much of any strength degradation caused by cycling during manufacturing of the exclusion device100,500may be recovered by the time the exclusion device100,500is received by a user.

In other example embodiments, springs may be constructed from stainless steel, polymers, or any other suitable biocompatible elastic materials.

Some example methods of making exclusion devices100for anatomical structure may include one or more of the following operations. A first spring110may be operatively connected between a first beam106and a second beam108to exert a closing force on the first beam106and the second beam108. The first spring110may be generally U-shaped and comprises a respective first end portion164and a respective second end portion166generally opposite a connecting portion168.

In some example embodiments, the method may further include operatively connecting a second spring112between the first beam106and the second beam108to exert the closing force on the first beam106and the second beam108. The second spring112may be generally U-shaped and may comprise a respective first end portion164and a respective second end portion166generally opposite a respective connecting portion168.

Some example methods of occluding an anatomical structure may include one or more of the following operations. An exclusion device100may be delivered to a surgical site in a closed configuration. The exclusion device100may include a first beam106, a second beam108, and a first spring110operatively coupled to the first beam106and the second beam108to exert a closing force on the first beam106and the second beam108. The first spring110may be generally U-shaped and/or may include a first end portion164and a second end portion166generally opposite a connecting portion168. The first spring110may include a first reverse bend portion170between the connecting portion168and the first end portion164and a second reverse bend portion172between the connecting portion168and the second end portion166. The method may include reconfiguring the exclusion device100from the closed configuration to an open configuration. The method may include positioning the exclusion device100around an anatomical structure10. The method may include reconfiguring the exclusion device100into the closed configuration to at least partially occlude the anatomical structure10.

In some example embodiments, the method may further include detaching the exclusion device100from an application instrument300. The method may include withdrawing the application instrument300. The method may include maintaining the exclusion device100in the closed configuration using the first spring110.

In some example embodiments, the closing force exerted by the first spring110may vary with a temperature of the first spring110. The method may include increasing the closing force exerted by the first spring110by increasing the temperature of the first spring110.

In some example embodiments, the exclusion device100may include a left atrial appendage occlusion clip. Positioning the exclusion device100around the anatomical structure10may include positioning the left atrial appendage occlusion clip around a left atrial appendage. At least partially occluding the anatomical structure10may include at least partially occluding the left atrial appendage.

FIG.16is a detailed elevation view of the jaws312,314of the exclusion device application instrument300ofFIG.4with the exclusion device100ofFIG.1in an open configuration, andFIG.17is an elevation view of the exclusion device100ofFIG.1in the open configuration and without the cover200, all in accordance with at least some aspects of the present disclosure. Referring toFIGS.1and4(closed configuration) andFIGS.5,16, and17(open configuration), in the illustrated embodiment, portions of the cover200are stretched when the exclusion device100is reconfigured from the closed configuration to the open configuration. In particular, in this example embodiment, portions of the generally tubular cover200generally between the ends114,116,118,120of the beams106,108and the springs110,112, as indicated by arrows202,204,206,208are circumferentially stretched to a stretched circumference201that is a multiple of the relaxed circumference203. As used herein, “circumference” may refer to a length of a perimeter of a cross section, taken generally perpendicularly to a local longitudinal direction, of a generally tubular body. The cross section may be non-circular, such as when the cover200is stretched between the beams106,108and the springs110,112as shown inFIGS.5and6. In the illustrated embodiment, portions of the cover200are stretched to a stretched circumference201of about two times (2×) to about three times (3×) of the relaxed circumference203when the exclusion device100is in the open configuration. In the illustrated embodiment, in the open configuration, the circumference of the entire generally toroidal cover200may stretch to less than about 2× of its relaxed circumference, even when particular generally tubular portions of the cover200are stretched to a stretched circumference201of about 2× to about 3× of their relaxed circumference203.

FIG.18is a perspective view of an example cover200, according to at least some aspects of the present disclosure. In the illustrated embodiment, the cover200is constructed from a woven fabric, such as a circular knit fabric. For example, a fabric having a circular warp knit braid with about 35 courses per inch (CPI) to about 45 CPI, such as about 38 CPI may be utilized. The fabric may be woven from a biocompatible material, such as texturized polyethylene terephthalate (PET) yarn.

In some example embodiments, the fabric of the cover200may define a generally tubular shape which is configured to extend generally toroidally around the beams106,108and springs110,112. The fabric of the cover200may be heat set on a mandrel to maintain its generally tubular form. In some example embodiments, the fabric may be generally flexible and compliant, so the cross section of the generally tubular shape may vary with the configuration of the exclusion device100and/or with the shape of the components within the cover200.

In alternative example embodiments, the cover200may be constructed from other woven fabrics having different weave patterns and/or from non-woven fabrics. In alternative example embodiments, the cover200may comprise multiple layers (plies) of texturized yarn, for example. The present disclosure contemplates that a large number of layers may add bulk to the weave and/or may reduce flexibility. Accordingly, some example embodiments providing relatively small profile exclusion devices100may include covers200including relatively few layers of fabric.

Referring toFIG.18, in some example embodiments, the cover200may be constructed from two or more sections210,212, which may be joined together to secure the cover200over the underlying structure of the exclusion device100in a generally toroidal manner. For example, the first section210may be welded to the second section212at a first joint214and/or at a second joint216. Similarly, a cover200formed from a single section of tubular fabric may be welded to itself at a similar joint to form a generally toroidal shape. In some example embodiments, one of the first section210and the second section212(or ends of a single section) may be overlapped with respect to the other, and one or more welds may extend generally radially to join the first section210and the second section212. Example welding methods include, without limitation, ultrasonic welding and heat welding. More generally, various example attachment methods (e.g., welding) may be selected and configured to minimize thickness and/or to minimize disruption of the tissue ingrowth function of the cover200.

FIGS.19and20are detailed views of an example ultrasonic weld218in an exclusion device100cover200, all in accordance with at least some aspects of the present disclosure. Referring toFIGS.18-20, the ultrasonic weld218may be used at one of the joints214,216to couple the first section210and the second section212. Generally, the ultrasonic weld218is relatively small in size and/or has an irregular periphery220, which may facilitate tissue ingrowth into the cover200near the weld218. The ultrasonic weld218may be relatively small compared to the relaxed diameter205of the cover200. For example, in one embodiment, the relaxed diameter205of the cover200may be about 3.0 mm and the size222of the ultrasonic weld218may be about 2.0 mm2. Accordingly, tissue ingrowth into the cover200and/or beams106,108may be minimally affected proximate the joints214,216. The ultrasonic weld218may be created at a position adjacent to a generally flat portion of one of the beams106,108, such as by using the beam106,108in cooperation with the ultrasonic horn to create the weld218. In various example embodiments, the pressure, power, duration, and horn geometry may be adapted to produce the desired ultrasonic weld218.

Some example methods of making an exclusion device100for an anatomical structure10may include one or more of the following operations. The clamping portion102,104of an exclusion device100comprising a beam106,108and a biocompatible fabric cover200may be assembled. The cover200may be secured on the beam106,108by ultrasonic welding a first portion of the cover200to a second portion of the cover200. The ultrasonic welding operation may include overlapping the first portion of the cover200and the second portion of the cover200. The ultrasonic welding operation may include applying ultrasonic energy to the overlapped first portion of the cover200and the second portion of the cover200to create at least one ultrasonic weld218configured and arranged to facilitate tissue ingrowth into the cover200near the ultrasonic weld218. The overlapping the first portion of the cover and the second portion of the cover operation may include positioning the second portion of the cover generally radially within the first portion of the cover. The ultrasonic welding operation may include applying ultrasonic energy at about 40 kHz.

In other example embodiments, alternative methods of coupling portions of the cover200may be employed. For example, some embodiments may utilize hand-sewn suturing to couple portions of the cover200. In other example embodiments, heat welding may be utilized.

FIG.21is a detailed perspective view of a portion of a cover200including an example heat weld224, according to at least some aspects of the present disclosure. In this example embodiment, an externally applied heat source (e.g., a heating element226) may be used in cooperation with an inner mandrel228(e.g., a generally flat portion of a beam106,108(FIG.3), such as outwardly facing surfaces158,160(FIG.13)) to form the heat weld224. In some example embodiments, a protective sheet230may be positioned between the heating element226and the fabric of the cover200. The protective sheet230may include polytetrafluoroethylene. Use of the protective sheet230in the heat welding operation may reduce overheating, stringing, discoloration, and/or burns. In this example embodiment, a portion of the second section212of the cover200is positioned generally radially within a portion of the first section210of the cover200in an overlapping fashion. The heat weld224is formed in the overlapped portion of the cover200.

Some example methods of making an exclusion device100for an anatomical structure10may include one or more of the following operations. A clamping portion102,104of an exclusion device100comprising a beam106,108and a biocompatible fabric cover200may be assembled. The cover200may be secured on the beam106,108by heat welding a first portion of the cover200to a second portion of the cover200. The heat welding operation may include overlapping the first portion of the cover200and the second portion of the cover200. The heat welding operation may include applying heat to the overlapped first portion of the cover200and the second portion of the cover200to create at least one heat weld224configured and arranged to facilitate tissue ingrowth into the cover200proximate the at least one heat weld224. The heat welding operation may include positioning a protective sheet230between a heat source226and the cover200and/or applying heat to the first portion of the cover200and the second portion of the cover200through the protective sheet230using the heat source226.

FIG.22is an exploded view of the end effector306ofFIGS.4and5, according to at least some aspects of the present disclosure. In the illustrated embodiment, the end effector306includes a head320, which is configured to be disposed distally on the shaft304. The stationary jaw312is fixedly disposed on the head320, and the movable jaw314is movably disposed on the head320. In this example embodiment, the stationary jaw312is integrally formed with the head320. In alternative embodiments, the stationary jaw312may include a separately formed component that is affixed to the head320.

In the illustrated embodiment, the movable jaw314is integrally formed with a traveler322. In alternative example embodiments, the movable jaw314may include a separately formed component that is affixed to the traveler322. The traveler322is movably disposed on the head320to produce a generally parallel opening motion of the exclusion clip100. The end effector306may include at least one friction reduction element operatively interposing the traveler322and the head320. For example, in this embodiment, the traveler322includes posts324,326, to which one or more friction reduction elements, such as ball bearings328,330, are coupled. The ball bearings328,330engage a track332on the head320to provide generally low-friction, proximal-distal motion of the second jaw314. Other embodiments may include one or more alternative friction reduction elements, such as one or more rollers and/or one or more low-friction sliders.

The present disclosure contemplates that, generally, it may be desirable to reduce friction and/or other forces opposing opening and/or closing of the exclusion device100. For example, a relatively low force application requirement for the user may be more comfortable and/or more controllable for users. Additionally, in the illustrated embodiment, the springs110,112of the exclusion device100provide the primary force that moves the exclusion device100from the open configuration to the closed configuration. Accordingly, smooth operation of the application instrument300in the closing direction may be improved when the resistance to closing (e.g., friction in the end effector306) is reduced.

Referring toFIGS.4,5,16, and22, in the illustrated embodiment, an opening cable334extends through the shaft304and operatively couples the first actuator308and the end effector306. Specifically, the opening cable334is operatively coupled to the traveler322to pull the traveler322generally proximally to open the exclusion device100. The opening cable334may include, for example, a multi-stranded stainless steel cable. The opening cable334may be constructed with a pre-attached ball and/or loop to facilitate assembly of the application instrument300, such as without a crimping fixture. The present disclosure contemplates that variations in the length of the opening cable334may affect the aperture of the jaws312,314and/or the exclusion device100. Accordingly, manufacturing tolerances may be established to ensure proper operation of the application instrument300.

In the illustrated embodiment, a deployment cable336extends through the shaft304and operatively couples the second actuator310and the end effector306. Specifically, the deployment cable336is operatively coupled to the sutures316,318to deploy the exclusion device100. The deployment cable336may include, for example, a multi-stranded stainless steel cable. The deployment cable336may include individual portions extending to respective jaws312,314. In some example embodiments, movement of the movable jaw314between the open and closed configurations may affect the tension, slack, and/or routing of the deployment cable336. Accordingly, some example embodiments may include one or more cable management elements. For example, the illustrated embodiment includes a cable management pin338disposed on the head320. The deployment cable336is routed around the cable management pin338so that excessive slack is not created in the deployment cable336when the movable jaw314is in the open configuration. More generally, the cable management elements, such as the cable management pin338, may allow the movable jaw314to move without causing relative movement of the deployment cable336.

Referring toFIG.22, in the illustrated embodiment, the end effector306includes a cover340positioned generally over the traveler322and track332mechanism. In some example embodiments, the cover340may engage the head320to provide a generally smooth exterior surface for the end effector306. The cover340may be secured to the head320by one or more threaded fasteners (e.g., screws), one or more welds, and/or one or more rivets342. In the illustrated embodiment, the rivets342are secured using a swage riveting technique and/or an orbital riveting technique, which may provide a generally smooth exterior surface (e.g., lacking sharp edges that might act as a catch point to cut or snag tissue) and which may minimize the risk of loose parts. In the illustrated embodiment, the rivets342are built-in to the head320; however, in some alternative embodiments, the rivets342may be provided as separate components.

FIG.23is a perspective view of an alternative example exclusion device100application instrument600, in accordance with at least some aspects of the present disclosure. This example application instrument600is generally similar to the application instrument300ofFIGS.4and5, and repeated description of similar components and functions is omitted for brevity. In the illustrated embodiment, the application instrument600includes a generally proximal handle portion602, an elongated, malleable shaft604extending distally from the handle portion602, and an end effector606disposed distally on the shaft604.

In this example embodiment, the end effector606comprises a generally loop-shaped frame608, which is configured to hold the exclusion device100. In contrast to the movable jaw314arrangement ofFIGS.4and5, in this example embodiment, the frame608is generally rigid and non-movable. In the illustrated embodiment, one clamping portion102of the exclusion device100is releasably secured to a first segment612of the frame (e.g., a distal segment in this embodiment). The other clamping portion104is releasably secured to a second segment614of the frame608(e.g., a proximal segment in this embodiment), which may be generally opposite the first segment612, forming a generally rectangular opening for the exclusion device100.

In the illustrated embodiment, the end effector606is arranged to reconfigure the exclusion device100between open and closed configurations and to release the exclusion device100based on operation of one or more actuators616,618on the handle portion602by the user. For example, operation of the first actuator616may pull one or more connecting elements620to reconfigure the exclusion device100to the open configuration. In some example embodiments, the end effector606may be configured for substantially parallel opening of the first clamping portion102and second clamping portion104of the exclusion device100. In some example embodiments, one or more strongback elements622may operatively interpose the frame608and the exclusion device100. In the illustrated embodiment, the exclusion device100is releasably retained in the frame608by sutures624,626,628,630. Operation of the second actuator618may release the sutures624,626,628,630, which may deploy the exclusion device100.

In some example embodiments, various components of the end effector306may be constructed from one or more metals and/or metal alloys, such as 17-4 stainless steel. Some components may be formed using metal injection molding processes. The present disclosure contemplates that metal injection molding is generally a cost-effective choice for tight tolerance parts with a good surface finish that minimizes secondary finishing. Further, metal injection molding allows for various metal selections.

In alternative example embodiments, various components of the end effector306may be constructed from one or more plastics. For example, various components of the end effector306may be constructed from plastics with high strength, low deflection properties. Some example plastic materials may include filler materials, such as glass or carbon fiber, to improve the structural capabilities. Thermoplastics, such as glass filled polyamide and/or polyetherimide, may be utilized. In some circumstances, thermoplastic parts may be less expensive than similar metal parts; however, plastics may not be as strong as metals (e.g., 17-4 stainless steel) so plastic components may need to be larger than corresponding metal components to provide similar strengths.

Some example methods of making an application instrument300for an exclusion device100for an anatomical structure10may include one or more of the following operations. An end effector306may be assembled, where the end effector306includes a head320configured to be disposed distally on a shaft304, a stationary jaw312fixedly disposed on the head320and configured to releasably couple to a first clamping portion102of an exclusion device100for an anatomical structure10, the exclusion device100being biased in a closing direction, and a movable jaw314movably disposed on the head320and configured to releasably couple to a second clamping portion104of the exclusion device100for the anatomical structure10. The end effector306may be coupled distally on the shaft304. A handle portion302may be coupled proximally on the shaft304.

In some example embodiments, a first actuator308on the handle portion302may be operatively connected to the end effector306so that the first actuator308is operative to move the movable jaw314to reconfigure the exclusion device100from the closed configuration to the open configuration. In some example embodiments, a second actuator310on the handle portion302may be operatively connected to the end effector306so that the second actuator310is operative to deploy the exclusion device100from the first jaw312and the second jaw314. Operatively connecting the second actuator314on the handle portion302to the end effector306may include routing a deployment cable336around at least one cable management pin338configured to allow movement of the movable jaw314without relative movement of the deployment cable338. Assembling the end effector306may include attaching a cover340to the head320. Attaching the cover340to the head320may include riveting the cover340to the head320.

Some example methods of using an application instrument300for an exclusion device100for an anatomical structure10may include one or more of the following operations. A first actuator308on a handle portion302of an application instrument300carrying an exclusion device100may be operated to reconfigure the exclusion device100into an open configuration. An end effector306of the application instrument300may be positioned to locate the exclusion device100on an anatomical structure10. The first actuator308may be operated to reconfigure the exclusion device100into a closed configuration on the anatomical structure10. A second actuator310on a handle portion302of the application instrument300may be operated to deploy the exclusion device100from the end effector306.

In some example embodiments, the end effector306may include a head320configured to be disposed distally on a shaft304, a stationary jaw312fixedly disposed on the head320and configured to releasably couple to a first clamping portion102of the exclusion device100. The exclusion device100may be biased in a closing direction. A movable jaw314may be movably disposed on the head320and configured to releasably couple to a second clamping portion104of the exclusion device100. Operating the first actuator308on the handle portion302of the application instrument300carrying the exclusion device100to reconfigure the exclusion device100into the open configuration may include moving the movable jaw314relative to the stationary jaw to reconfigure the exclusion device100from the closed configuration to the open configuration while the movable jaw314and the stationary jaw312are oriented generally in parallel. Operating the second actuator310on the handle portion302of the application instrument300to deploy the exclusion device100from the end effector306may include moving a deployment cable336around at least one cable management pin338configured to allow movement of the movable jaw314without relative movement of the deployment cable336.

Unless specifically indicated, it will be understood that the description of the structure, function, and/or methodology with respect to any illustrative embodiment herein may apply to any other illustrative embodiments. More generally, it is within the scope of the present disclosure to utilize any one or more features of any one or more example embodiments described herein in connection with any other one or more features of any other one or more other example embodiments described herein. Accordingly, any combination of any of the features or embodiments described herein is within the scope of this disclosure.

Following from the above description and invention summaries, it should be apparent to those of ordinary skill in the art that, while the methods and apparatuses herein described constitute example embodiments according to the present disclosure, it is to be understood that the scope of the disclosure contained herein is not limited to the above precise embodiments and that changes may be made without departing from the scope of the disclosure. Likewise, it is to be understood that it is not necessary to meet any or all of the identified advantages or objects disclosed herein in order to fall within the scope of the disclosure, since inherent and/or unforeseen advantages may exist even though they may not have been explicitly discussed herein.