Patent Description:
The subject invention is directed to surgical equipment, and more particularly to hemostatic clips used endoscopic surgical procedures.

Endoscopic or "minimally invasive" hemostatic clips are used in performance of hemostasis to stop and prevent re-bleeding, or in procedures such as ampullectomies, tissue repair and correction of other tissue defects. Such procedures are typically performed by grasping the tissue with the hemostatic clip. Benefits of using hemostatic clips in such procedures include reduced trauma to the patient, low re-bleeding rate, reduced opportunity for infection, and decreased recovery time. <CIT> discloses an hemostatic clamp, wherein a connecting sleeve and a socket sleeve are connected together if elastic clamp is pressed away, where connecting sleeve and socket sleeve are separated from each other if clamp is released to tissue. The release pin housing (sleeve <NUM>) is distal of the annular portion of the shaft spring (elastic clip <NUM>)such that the annular portion of elastic clip <NUM> is not around the sleeve <NUM> but entirely proximal thereto.

The subject invention provides an improved mechanism for a hemostatic clip. The novel design allows for a shorter deployed clip body, improved tissue grasping and clip locking, and an improved disconnecting feature, which are described in detail herein below, along with other novel devices and systems.

The present invention concerns a device for applying a hemostatic clip assembly comprising the features defined in independent claim <NUM>. The subject disclosure is directed to a new and useful device for applying a hemostatic clip assembly. The device includes a proximal delivery catheter including a proximal handle assembly and an elongated catheter body extending distally from the proximal handle assembly. The elongated catheter body defining a longitudinal axis. The device includes a distal clip assembly removably connected to a distal end of the elongated catheter body. The distal clip assembly includes a distal clip housing, a jaw assembly having a pair of cooperating jaw members fixed to the distal clip housing by a first pin, the first pin oriented orthogonally relative to the longitudinal axis, and a jaw adapter yoke operatively connected to the jaw members. The proximal delivery catheter is configured and adapted to transmit linear motion along the longitudinal axis and torsion about the longitudinal axis to at least a portion of the distal clip assembly. At least one of the jaw members is configured and adapted to rotate about the first pin between an open configuration and a closed configuration.

In some embodiments, the distal clip housing includes a pair of spaced apart arms defining a slot configured and adapted to provide clearance for respective proximal portions of the jaw members to rotate relative the first pin. The distal clip assembly can include a second pin connecting between the jaw members and the jaw adapter yoke. Each jaw member can include a proximal body portion and a distal end effector. The proximal body portion of each jaw member can include a respective cam slot configured and adapted to receive the second pin and a pivot aperture configured and adapted to receive the first pin. The second pin can be configured and adapted to translate within the cam slots to move axially relative to the distal clip housing and the jaw assembly to move the jaw members between the open configuration, where respective distal tips of the jaw members are moved away from one another, the closed configuration where the respective distal tips of the jaw members are approximated towards one another to grasp tissue, and a locked configuration.

Each cam slot can define a distal portion and a proximal portion. The distal portion of each cam slot can be angled relative to the proximal portion of each cam slot. The proximal portion of each cam slot can define a proximal axis extending in a first direction, the distal portion of each cam slot can define a distal axis extending at an oblique angle relative to the proximal axis, and the distal axes of each cam slot can be positioned at opposite angles relative to one another. Each cam slot can include a proximal locking neck projecting into the cam slot defining a proximal locking area. The jaw members can be in the locked configuration when the second pin is proximal relative to the proximal locking neck in the proximal locking area. The proximal locking neck can include at least one of a protrusion projecting into the cam slot or a tapered portion.

The jaw adapter yoke can include a proximal receiving portion and the proximal delivery catheter can include a release pin having a distal portion configured and adapted to be received within the proximal receiving portion of the jaw adapter yoke to transmit axial and rotational force to the jaw adapter yoke. The proximal delivery catheter can include a drive wire coupled to a proximal portion of the release pin to transmit linear and rotational motion from the drive wire to the jaw adapter yoke. The proximal handle assembly can include an actuation portion coupled to a proximal end of the drive wire, and a grasping portion. The actuation portion is configured and adapted to translate relative to the grasping portion to apply axial force to the drive wire.

The proximal delivery catheter can include a shaft spring between a proximal end of the distal clip assembly and the distal end of the catheter body. The shaft spring can include at least one arm removably coupled to the distal clip housing. The at least one arm can include an outwardly extending flange that removably engages with an aperture defined in the proximal end of the distal clip housing. The proximal delivery catheter can include a release pin releasably connected to the jaw adapter yoke, and a release pin housing positioned around the release pin. An annular portion of the shaft spring can be positioned around the release pin housing. The release pin can be configured and adapted to interfere with the annular portion of the shaft spring as the release pin housing moves proximally to move the shaft spring proximally relative to the distal clip housing and release the outwardly extending flange of the at least one arm from the aperture of the distal clip housing. The release pin housing can have at least one non-circular cross-section portion and the annular portion of the shaft spring can be proximal to the at least one non-circular cross-section portion. The non-circular cross-section portion can be configured and adapted to interfere with the annular portion of the shaft spring upon proximal translation of the release pin housing.

The release pin has a distal portion, a proximal portion, and a neck portion therebetween. The distal portion of the release pin can be configured and adapted to be received within a bore of the jaw adapter yoke to transmit axial force to the jaw adapter yoke. The neck portion of the release pin can be configured and adapted to shear when an axial force is applied to the release pin in a proximal direction, thereby separating the distal portion from the proximal portion and releasing the proximal portion of the release pin from the distal clip assembly. The neck portion of the release pin can have a smaller diameter than the proximal portion of the release pin and the distal portion of the release pin, thereby configured and adapted to create a stress concentration to limit elongation during a shear. The release pin can include a silver material.

In accordance with another aspect, a proximal delivery catheter includes a proximal handle assembly, an elongated catheter body defining a longitudinal axis and extending distally from the proximal handle assembly, and a drive wire movably positioned within the elongated catheter body. A release pin assembly is coupled to a distal end of the drive wire. The release pin assembly including a release pin and a release pin housing positioned outward from the release pin. A shaft spring is positioned outward from the release pin housing. The shaft spring includes an annular portion wherein the release pin housing is configured and adapted to interfere with the annular portion of the shaft spring upon proximal translation of the release pin housing. A distal clip assembly is removably connected to the distal end of the elongated catheter body. The proximal delivery catheter is configured to transmit linear motion along and torsion about the longitudinal axis to at least a portion of the distal clip assembly.

The release pin, release pin housing, shaft spring and drive wire are similar to those described above. The distal clip assembly can include a distal clip housing, a jaw assembly having a pair of cooperating jaw members fixed to the distal clip housing by a first pin, and a jaw adapter yoke operatively connected to the jaw members, as previously described. A proximal body portion of each jaw member can include a respective cam slot, like cam slots described above. The distal clip housing can include a pair of spaced apart arms, like those described above. The distal clip assembly can include a second pin like that described above. Each cam slot can include a proximal locking neck projecting into the cam slot defining a proximal locking area, similar to the proximal locking neck and proximal locking area described above. Each cam slot can define a distal portion and a proximal portion, as previously described. The proximal handle assembly can include an actuation portion and a grasping portion, as described above.

In accordance with another aspect, a method for firing a hemostatic clip includes positioning a distal clip assembly proximate to a target location. The distal clip assembly includes a distal clip housing, a jaw assembly having a pair of cooperating jaw members fixed to the distal clip housing by a first pin, and a jaw adapter yoke operatively connected to the jaw members. The method includes translating an actuation portion of a proximal handle assembly of a proximal delivery catheter relative to a grasping portion of the proximal handle assembly in at least one of a proximal direction or a distal direction. The proximal delivery catheter includes an elongated catheter body extending distally from the proximal handle assembly. The elongated catheter body defines a longitudinal axis. The actuation portion is operatively connected to the jaw adapter yoke via a drive wire to transmit linear motion along the longitudinal axis and torsion about the longitudinal axis to the jaw adapter yoke. Tthe linear motion of the jaw adapter yoke transmits the linear motion to a second pin positioned within a cam slot of at least one jaw member, thereby rotating at least one of the jaw members about the first pin between an open configuration and a closed configuration.

In some embodiments, translating the actuation portion includes translating the actuation portion in the proximal direction to transmit the linear motion in the proximal direction to the second pin to lock the second pin behind a lock protrusion of the cam slot to lock at least one of the jaw members in a locked configuration. Translating the actuation portion can include translating the actuation portion further in the proximal direction to transmit further linear motion in the proximal direction to a release pin coupled to the drive wire, the axial force on the release pin in the proximal direction shearing the release pin at a neck portion, thereby separating a proximal portion of the release pin from a proximal portion of a jaw adapter yoke.

In some embodiments, the axial force on the release pin in the proximal direction causes interference between a release pin housing with an annular portion of a shaft spring causing the shaft spring to move proximally relative to the distal clip housing and release an outwardly extending flange of at least one arm of the shaft spring from an aperture of the distal clip housing. Translating the drive wire in the proximal direction can include translating a jaw adapter yoke in the proximal direction. Translating the actuation portion of the proximal delivery catheter can include translating the actuation portion in the distal direction to transmit the axial force in the distal direction to the second pin causing the at least one jaw to rotate about the first pin to the open configuration.

In accordance with another aspect, a hemostatic clip assembly includes a distal clip housing defining a longitudinal axis, a jaw assembly having a pair of cooperating jaw members fixed to the distal clip housing by a first pin, the first pin oriented orthogonally relative to the longitudinal axis, and a jaw adapter yoke operatively connected to the jaw members. The jaw adapter yoke is configured and adapted to translate axially along the longitudinal axis and rotate about the longitudinal axis. At least one of the jaw members is configured and adapted to rotate about the first pin between an open configuration and a closed configuration.

The distal clip housing can include a pair of spaced apart arms, similar to those described above. The hemostatic clip assembly can include a second pin, similar to that described above. Each jaw member and its respective cam slot can be similar to those described above.

These and other features of the hemostatic clip of the subject invention will become more readily apparent to those having ordinary skill in the art to which the subject invention appertains from the detailed description of the preferred embodiments taken in conjunction with the following brief description of the drawings.

So that those skilled in the art will readily understand how to make and use the gas circulation system of the subject invention without undue experimentation, preferred embodiments thereof will be described in detail herein below with reference to the figures wherein:.

Referring now to the drawings wherein like reference numerals identify similar structural elements and features of the subject invention, there is illustrated in <FIG> a gas circulation system for performing an endoscopic surgical procedure in a surgical cavity of a patient, and more particularly, for performing a robotically assisted laparoscopic surgical procedure in the abdominal cavity of a patient that is constructed in accordance with a preferred embodiment of the subject disclosure and is designated generally by reference numeral <NUM>.

As shown in <FIG>, a surgical device <NUM> for applying a hemostatic clip assembly <NUM> includes proximal delivery catheter <NUM> and the distal clip assembly <NUM>. The distal clip assembly <NUM>, e.g. a hemostasis clip, separates from the delivery catheter <NUM> to function as a short-term implant to stop and prevent re-bleeding, or in procedures such as ampullectomies, tissue repair and correction of other tissue defects. Such procedures are typically performed by grasping the tissue with the hemostatic clip. Using hemostatic clips in such procedures can result in benefits such as reduced trauma to the patient, low re-bleeding rate, reduced opportunity for infection, and decreased recovery time.

With continued reference to <FIG>, the proximal delivery catheter <NUM> has a proximal handle assembly <NUM> and an elongated catheter body <NUM> extending distally from the proximal handle assembly <NUM>. The elongated catheter body <NUM> defines a longitudinal axis A. The proximal handle assembly <NUM> includes an actuation portion <NUM> coupled to a proximal end <NUM> of the drive wire <NUM>, and a grasping portion <NUM>. The actuation portion <NUM> is configured and adapted to translate along the longitudinal axis A, relative to the grasping portion <NUM>, to apply an axial force to the drive wire <NUM>. Grasping portion <NUM> and actuation portion <NUM> are configured and adapted to rotate relative to a cap <NUM> and catheter body <NUM>, thereby also rotating drive wire <NUM>. Internal annular slots on the distal portion of grasping portion <NUM> interact with annular tabs on inside diameter of end cap <NUM> to prevent axial motion of actuation portion <NUM> and grasping portion <NUM> but allow rotation.

With reference now to <FIG>, the proximal delivery catheter <NUM> includes a shaft spring <NUM> between a proximal end of the distal clip assembly <NUM> and a distal end of the catheter body <NUM>. The distal clip assembly <NUM> includes a distal clip housing <NUM> and a jaw assembly <NUM> pivotally connected to the distal clip housing <NUM>. The proximal delivery catheter <NUM> includes a shaft bearing <NUM> coupled to the distal clip housing <NUM> via the shaft spring <NUM>, and a bearing ring <NUM> mated with a proximal end of the shaft bearing <NUM>. The jaw assembly <NUM> has a pair of cooperating jaw members <NUM> fixed to the distal clip housing <NUM> by a first pin <NUM>. The first pin <NUM> is oriented orthogonally relative to the longitudinal axis A. The shaft spring <NUM> includes arms <NUM> configured and adapted to be removably coupled to the distal clip housing <NUM>, described in more detail below. The hemostatic clip assembly <NUM> is removably connected to a distal end <NUM> of the elongated catheter body <NUM> via the shaft spring <NUM>. The proximal delivery catheter <NUM> is configured and adapted to transmit linear motion along the longitudinal axis A and torsion about the longitudinal axis A to at least a portion of the distal clip assembly <NUM>.

As shown in <FIG>, the distal clip assembly <NUM> includes a jaw adapter yoke <NUM> connected to the jaw members <NUM> via a second pin <NUM>. The jaw members <NUM> are configured and adapted to rotate about the first pin <NUM> between an open configuration and a closed configuration. Each jaw member <NUM> includes a proximal body portion <NUM> and a distal end effector <NUM>. The proximal body portion <NUM> of each jaw member <NUM> includes a respective cam slot <NUM> configured and adapted to receive the second pin <NUM>. Jaw members <NUM> are driven by the second pin <NUM>, e.g. a cam pin, moving along the cam slots <NUM> of the jaw members <NUM>. The second pin <NUM> is configured and adapted to translate within the cam slots <NUM> to move axially relative to the distal clip housing <NUM> and the jaw assembly <NUM> to move the jaw members <NUM> between the open configuration where respective distal tips <NUM> of the jaw members <NUM> are moved away from one another, the closed configuration where the respective distal tips <NUM> of the jaw members <NUM> are approximated towards one another to grasp tissue, and a locked configuration.

With continued reference to <FIG>, each jaw member <NUM> includes a pivot aperture <NUM> configured and adapted to receive the first pin <NUM>. Each jaw member <NUM> of the jaw assembly <NUM> is identical to the other member <NUM>, allowing additional economy of scale. The distal end effectors <NUM> of each jaw member <NUM> can include at least one pointed peak, multiple peaks, of different or similar size at their distal tips <NUM>. Distal end effectors <NUM> could also terminate in a combination of pointed peaks and rounded peaks to balance tissue pressure, allowing jaw members <NUM> to hook tissue with at least one peak and provide atraumatic contact with at least one peak. As shown in <FIG>, the tooth (or teeth, peaks, etc,) may create an angle ω relative to an axis J of their respective jaw arms <NUM> between zero and <NUM> degrees, optimizing the approach angle of distal tips <NUM> relative to tissue surface. In the embodiment of <FIG>, the tooth (or teeth, peaks, etc,) may create an angle ω relative to an axis J of their respective jaw arms <NUM> between zero and <NUM> degrees, optimizing the approach angle of distal tips <NUM> relative to tissue surface. In the embodiment of <FIG>, the angle ω of a tip axis T relative to axis J is approximately <NUM> degrees. It is contemplated, however, that the angle ω could be at <NUM> degrees, such that the tip simply extends from axis J, it could be at <NUM> degrees, or <NUM> degrees, where the tip is hooked around such that the tip axis T direction is parallel to axis J. The angle and design of jaw members <NUM> will be optimized for single jaw tissue retention force during manipulation or tissue apposition. The distance between the pivot aperture <NUM> and the cam slot <NUM> dictate the moment arm that translates axial translation to jaw rotation/actuation.

As shown in <FIG>, each cam slot <NUM> defines a distal portion <NUM> and a proximal portion <NUM>. The distal portion <NUM> of each cam slot <NUM> is angled relative to the proximal portion <NUM> of each cam slot <NUM>. The proximal portion <NUM> of each cam slot <NUM> defines a proximal axis P extending in a first direction. The distal portion <NUM> of each cam slot <NUM> defines a distal axis D extending at an oblique angle θ relative to the proximal axis P, and the distal axes D of each cam slot <NUM> are positioned at opposite angles relative to one another, as shown in <FIG>. The angle of a respective distal axis D relative to proximal axis P can be fine-tuned to provide optimal tissue clamping force given a user's maximum acceptable input force.

With continued reference to <FIG>, each cam slot <NUM> includes a proximal locking neck <NUM>, e.g. a locking feature, projecting into the cam slot <NUM> defining a proximal locking area <NUM>. The jaw members <NUM> are in the locked configuration when the second pin <NUM> is proximal relative to the proximal locking neck <NUM> in the proximal locking area <NUM>. The proximal locking neck <NUM> includes a protrusion <NUM> projecting into the cam slot <NUM>. Lock protrusion <NUM>, e.g. a detent, creates a narrowing of cam slot <NUM> to form the proximal locking neck <NUM> that interferes with the outer diameter of the second pin <NUM> as it moves axially in the proximal direction. The continued axial translation of pin <NUM> forces a widening of the cam slot <NUM> in an elastic manner and creates an additional resistance force on the internal drivetrain, e.g. release pin <NUM> and shaft spring <NUM>. Once the second pin <NUM> crests the inflection point on the protrusion <NUM>, it will snap into place behind the protrusion <NUM>, effectively locking the jaws in a closed position. The shape of lock protrusion can vary and can be an arcuate, triangular, or slanted feature. Lock protrusion <NUM> may also be achieved by reversing the slope of cam slot <NUM> such that it inflects passed the <NUM> degree orientation with respect to the axis A of the catheter, described in more detail below. Various embodiments for the proximal locking neck are described below in Figs. <NUM>-<NUM>.

As shown in <FIG> and <FIG>, the distal clip housing <NUM> includes a pair of spaced apart arms <NUM> defining a slot <NUM> configured and adapted to provide clearance for respective proximal portions <NUM> of the jaw members <NUM> to rotate relative the first pin <NUM>. The distal clip housing <NUM> connects to the shaft spring <NUM> via apertures <NUM> spaced apart about a periphery of a proximal end <NUM> of the distal clip housing <NUM>. Distal clip housing <NUM> couples to the shaft bearing <NUM> via shaft spring <NUM>. Flanges <NUM> from shaft spring <NUM> intersect transverse apertures <NUM> in housing <NUM> and transverse apertures <NUM> of shaft bearing <NUM>, effectively restraining axial and angular motion in the shaft. A lip <NUM> of shaft bearing <NUM> mates with an inward flange <NUM> of the bearing ring <NUM> (shown in <FIG>) to create a joint allowing rotation of shaft bearing <NUM> relative to bearing ring <NUM> about longitudinal axis A, but no axial motion along longitudinal axis A. Bearing ring <NUM> is welded to the distal end <NUM> elongated catheter body <NUM> via a flat spring <NUM> portion of catheter body <NUM>. An outer sleeve <NUM> is positioned outwards from shaft bearing <NUM>, between distal clip housing <NUM> and bearing ring <NUM>. The distal clip housing <NUM> includes a transverse hole <NUM> oriented perpendicular to the longitudinal axis A to accept the first pin <NUM>, e.g. the pivot pin, which couples to jaw members <NUM>.

As shown in <FIG> and <FIG>, the proximal delivery catheter <NUM> includes a pin assembly <NUM> comprised of a release pin <NUM>, e.g. a pin made of silver material, and a release pin housing <NUM>, e.g. a crimped hypotube. The silver material is a substantially ductile material that is resistant to strain hardening and it is contemplated that materials with similar characteristics can be used. The release pin <NUM> includes a distal portion <NUM> configured and adapted to be received within the proximal receiving portion <NUM> of the jaw adapter yoke <NUM> to transmit axial force to the jaw adapter yoke <NUM>. The release pin <NUM> includes a neck portion <NUM> proximal to the distal portion <NUM>, and a proximal portion <NUM> proximal from the neck portion <NUM>. Release pin <NUM> has a formed head, e.g. the distal portion <NUM>, that sits inside of a distal counterbore <NUM> of the jaw adapter yoke <NUM>. The release pin <NUM> includes a stepped-in outer diameter that forms the neck portion <NUM>, e.g. a notch, having a stress concentration. The neck portion <NUM> creates a reliable failure point and the soft metal allows for precise break forces to be achieved via a critical diameter. The proximal portion <NUM> of the pin <NUM> is crimped inside the inner diameter of the release pin housing <NUM>, described in more detail below. The drive wire <NUM> is mechanically coupled to a proximal portion of the release pin housing <NUM> via a laser weld <NUM> to transmit linear and rotational motion from the drive wire <NUM> to the release pin housing <NUM>, and in turn to the release pin <NUM> and then to the jaw adapter yoke <NUM>. The release pin <NUM> is housed inside jaw housing <NUM> and release pin housing <NUM>. The release pin <NUM> is mated inside the release pin housing <NUM> by one or more mechanical crimps that create a non-round cross section, see <FIG> with only the release pin housing <NUM> and release pin <NUM> shown. The distal portion <NUM> of release pin <NUM> seats inside the counterbore of proximal receiving portion <NUM> of jaw adapter yoke <NUM>, allowing tension or compression to be transmitted from the proximal drive wire <NUM> to the jaw members <NUM>.

With continued reference to <FIG>, release pin housing <NUM> includes torque flanges <NUM> at a distal end, crimped sections 154a and 154b proximal of the torque flanges, and straight body portion <NUM> proximal of the torque flanges. The crimped sections 154a and 154b form at least one non-round cross section, shown in <FIG>. The shaft spring <NUM> is pulled in a more proximal position than it would be when assembled in order for the details of the release pin <NUM> and jaw adaptor yoke <NUM> to be clear. The most proximal non-round cross section, <FIG>, has a larger diameter in a plane orthogonal to the longitudinal axis A than the clearance of the inner diameter of the annular portion <NUM> of shaft spring <NUM>. The straight body section <NUM> of release pin housing <NUM> translates freely relative to annular portion <NUM> during jaw actuation, permitting forward and backwards translation in this range. During clip firing, excessive proximal translation of release pin housing <NUM> causes the proximal most crimped section 154b to contact shaft spring <NUM> causing proximal axial translation of shaft spring <NUM> and disengagement of flanges <NUM> from distal clip housing <NUM>.

As shown in <FIG> and <FIG>, the jaw adapter yoke <NUM> includes a pin aperture <NUM> and is operatively connected to the jaw members <NUM> via second pin <NUM>. The jaw adapter yoke <NUM> is circular component with two arms <NUM> extending towards the distal end of the yoke <NUM> that form a slot <NUM> therebetween. The slot <NUM> allows the proximal portions <NUM> of the jaw members <NUM> rotate around first pin <NUM>. An aperture <NUM> is formed in each arm <NUM> and is in a transverse direction to a longitudinal axis of the jaw adapter yoke and the longitudinal axis A of the catheter body <NUM>. The apertures <NUM> receive the second pin <NUM> and can be assembled using orbital riveting or laser tack welding. The jaw adapter yoke <NUM> includes a proximal receiving portion <NUM> and moves linearly inside of distal clip housing <NUM> to drive second pin <NUM> along the cam slots <NUM>. The jaw adapter yoke <NUM> has an axial through hole comprised of a distal counterbore <NUM> for mating with a distal portion <NUM> of the release pin <NUM>, and a proximal counterbore <NUM> for receiving the proximal portion <NUM> of the release pin <NUM>. The proximal receiving portion <NUM> of the jaw adapter yoke <NUM> has an inner surface that generally conforms with the release pin <NUM> such that a conical surface <NUM> on the inner surface of the yoke <NUM> mate with a conical surface <NUM> on release pin <NUM> to transmit axial force from the release pin <NUM> to the jaw adapter yoke <NUM>. Jaw adapter yoke includes a transverse slot <NUM> configured and adapted to mate with the torque flanges <NUM> of the release pin housing <NUM> to allow for torque transmission directly from the release pin housing <NUM> to jaw adapter yoke <NUM> without exerting torsional stress on neck portion <NUM> of release pin <NUM>.

As shown in <FIG>, the flanges <NUM> of shaft spring <NUM> are bent outward at approximately <NUM>-degrees and removably engage with the apertures <NUM> defined about the periphery of the proximal end <NUM> of the distal clip housing <NUM> and apertures <NUM> of the shaft bearing <NUM>. The release pin assembly <NUM> (e.g. the release pin <NUM> and the release pin housing <NUM>) is positioned at least partially within the shaft spring <NUM>. Shaft spring <NUM> has a through hole in annular portion <NUM> that allows free axial translation of the straight body section <NUM> of release pin housing <NUM> during opening and closure of jaw members <NUM>. Because the maximum dimension Z of the non-round cross section 154b is greater than a diameter Y of the through hole of annular portion <NUM>, as shown in <FIG>, the outer diameter of release pin housing <NUM> interferes with the through hole of annular portion <NUM> upon axial translation in the proximal direction during "firing.

With reference now to <FIG>, some of the various configurations of device <NUM> are shown. In <FIG>, the device <NUM> is in the open configuration and the second pin <NUM> is translated to a distal position within each cam slot <NUM> such that the distal tips <NUM> of jaw members <NUM> are rotated away from one another. In <FIG>, the device <NUM> is in a closed configuration and the second pin <NUM> is translated in a more proximal position within each cam slot <NUM> relative to the open configuration, but second pin <NUM> is still distal of the locking neck <NUM> and the protrusion <NUM>. In the closed configuration, the respective distal tips <NUM> of the jaw members <NUM> are approximated towards one another to grasp tissue <NUM> (but not necessarily in abutment with one another). In <FIG>, the device <NUM> is in a locked configuration and the second pin <NUM> is in a proximal position relative to the locking neck <NUM> and its respective protrusion <NUM>. In the locked configuration, the second pin <NUM> is within the proximal locking area <NUM> of each cam slot <NUM>.

As shown in <FIG>, once the second pin <NUM> is in the proximal locking area <NUM>, further axial movement of the pin assembly <NUM> in a proximal direction (e.g. away from the tissue <NUM>) acts to "fire" the distal clip assembly <NUM> by releasing the distal clip assembly <NUM> from the proximal delivery catheter <NUM>. The further linear motion of the release pin <NUM> in the proximal direction puts the release pin <NUM> in tension against jaw adapter yoke <NUM> due to abutment between the conical surface <NUM> on the inner surface of the yoke <NUM> and the conical surface <NUM> on release pin <NUM>. This tension causes shear at the neck portion <NUM> of release pin, shown schematically by the arrow in <FIG>, and release from the proximal receiving portion <NUM>. The release force required to detach release pin <NUM> from the adapter yoke <NUM> can be tuned by the thickness of the neck portion <NUM>. As shown in <FIG>, a proximal non-round cross section 154b of release pin housing <NUM> interferes with an inner diameter of an annular portion <NUM> of shaft spring <NUM> when the jaws are fully closed and locked, as shown in <FIG>. When the drive wire <NUM> continues to translate backwards, release pin <NUM> shears at the neck portion <NUM> due to a stress concentration. Although silver is typically ductile, the stress concentration results in a more sudden, brittle failure at the minor diameter of the neck portion <NUM>. Continued proximal translation forces cause the release pin housing <NUM> to continue to interfere with the annular portion <NUM> of shaft spring <NUM>, driving it proximally, resulting in the deflection of flanges <NUM> and full release of the distal clip assembly <NUM> from the proximal delivery catheter <NUM>.

With continued reference to <FIG>, as the release pin <NUM> continues to move proximally relative to the jaw adapter yoke <NUM>, the shaft spring <NUM> moves along with the release pin and release pin housing. The motion of shaft spring <NUM> in the proximal direction creates deflection in the bent over flanges <NUM> of arms <NUM>, allowing them to pull out of the transverse apertures <NUM>, thereby releasing the distal clip assembly <NUM>. Full disengagement (e.g. "firing") of the distal clip assembly <NUM> is realized through both the shearing of the release pin <NUM> and the deflection of flanges <NUM> of shaft spring <NUM>. The neck portion <NUM> of the release pin is configured and adapted to shear when an axial force is applied to the release pin in a proximal direction, thereby separating the distal portion from the proximal portion and releasing the proximal portion of the release pin from the distal clip assembly. After firing, proximal delivery catheter <NUM> can then be removed from the surgical site, leaving the distal clip assembly <NUM> to function as a short-term implant.

With continued reference to <FIG>, a single assembly simultaneously shears (release pin <NUM>) and disengages a separate component (of flanges <NUM>) which improves the disconnect mechanism by synchronizing two release events. This also generates an improved disconnect mechanism that enhances the ability to reposition the clip assembly <NUM> prior to deployment by simplifying the feedback to the user into a single tactile signal. It also makes accidental deployment of the clip assembly <NUM> less likely, as fewer components are used to realize disengagement. Because there are fewer components, less space is needed in the distal clip assembly <NUM>, allowing for a shorter clip body. The shorter clip "stem" or overall length of deployed clip <NUM> relative to jaw size is seen as an improvement. Because torque transmission is achieved through a non-deforming, non-frangible linkage (via torque flanges <NUM> release pin housing <NUM>) angular deflection in the drive train (release pin <NUM>) is relieved and the potential for non-axial forces affecting the release force are minimized. The embodiments herein are described using silver for release pin <NUM>, which is a soft metal allowing for high-precision forming operations that result in highly consistent deployment forces. The soft metal and simplistic design allow for quick mechanical assembly, without the need for welds or more complicated joining technologies.

A method for firing a hemostatic clip assembly, e.g. distal clip assembly <NUM>, includes positioning the distal clip assembly proximate to a target location, e.g. near tissue <NUM>, as shown in <FIG>, and translating an actuation portion, e.g. actuation portion <NUM>, of a proximal handle assembly, e.g. proximal handle assembly <NUM>, of a proximal delivery catheter, e.g. proximal delivery catheter <NUM>, relative to a grasping portion, e.g. grasping portion <NUM>, of the proximal handle assembly in a proximal direction, thereby translating a drive wire, e.g. drive wire <NUM>. The actuation portion is operatively connected to a jaw adapter yoke, e.g. jaw adapter yoke <NUM>, via a drive wire, e.g. drive wire <NUM>, and a release pin, e.g. release pin <NUM>. Translating the drive wire in the proximal direction includes translating the jaw adapter yoke in the proximal direction. Prior to firing, however, the handle portion of the proximal delivery catheter can be translated in the distal direction to transmit an axial force in the distal direction to the second pin causing the at least one jaw to rotate about the first pin to the open configuration. In this way, the jaw assembly can go between the open position and closed position as much as desired prior to locking and firing. For closing, the linear motion of the jaw adapter yoke transmits the linear motion to a second pin, e.g. second pin <NUM>, positioned within a cam slot, e.g. cam slot <NUM>, of at least one jaw member, e.g. jaw members <NUM>, thereby rotating at least one of the jaw members about the first pin between an open configuration and a closed configuration. , as shown in <FIG>.

The method includes translating the actuation portion in the proximal direction to transmit the linear motion in the proximal direction to the second pin, as shown in <FIG>, to lock the second pin behind a lock protrusion, e.g. lock protrusion <NUM>, of the cam slot to lock at least one of the jaw members in a locked configuration, as shown in <FIG>. Translating the actuation portion includes translating the actuation portion further in the proximal direction to transmit further linear motion in the proximal direction to the release pin. The further linear motion in a proximal direction shearing the release pin at a neck portion, as shown in <FIG>, e.g. neck portion <NUM>, thereby separating a proximal portion, e.g. proximal portion <NUM>, of the release pin from a proximal receiving portion, e.g. proximal receiving portion <NUM>, of a jaw adapter yoke. , as shown in <FIG>.

The axial force on the release pin in the proximal direction causes abutting between an outer diameter of a release pin housing, e.g., release pin housing <NUM>, with an annular portion, e.g. annular portion <NUM>, of a shaft spring, e.g. shaft spring <NUM>, causing the shaft spring to move proximally relative to the distal clip housing and release an outwardly extending flange, e.g., outwardly extending flange <NUM>, of at least one arm, e.g., arms <NUM>, of the shaft spring from an aperture, e.g., aperture <NUM>, of the distal clip housing, as shown in <FIG>.

In accordance with some embodiments, a method for assembling a release pin assembly, e.g. release pin assembly <NUM>, for use in a proximal delivery catheter, e.g. proximal delivery catheter <NUM>, includes sliding a release pin, e.g. release pin <NUM>, inside of a distal counterbore, e.g. counterbore <NUM>, of a jaw adapter yoke, e.g. jaw adapter yoke <NUM>. The method includes sliding a release pin housing, e.g. release pin housing <NUM>, around a proximal portion, e.g. proximal portion <NUM>, of the pin, and mating torque flanges, e.g. torque flanges <NUM>, of the release pin housing with a transverse slot, e.g. transverse slot <NUM> of the jaw adapter yoke. The method includes crimping the release pin within the release pin housing by applying one or more mechanical crimps to an outer diameter of the release pin housing proximal to the torque flanges.

Referring now to <FIG>, several different embodiments for the jaw members are described. In <FIG>, an embodiment of a jaw member <NUM> is shown. Jaw member <NUM> is similar to jaw members <NUM> in that it can be used in the jaw assembly <NUM> and the distal clip assembly <NUM>. Jaw member <NUM> also includes a distal end effector <NUM> similar to distal end effector <NUM>. The main difference between jaw member <NUM> and jaw member <NUM> is that jaw member <NUM> includes a cam slot <NUM> in a proximal portion <NUM> of the jaw member <NUM> where the cam slot <NUM> includes a proximal locking neck <NUM> with two protrusions <NUM> projecting into the cam slot <NUM> defining a proximal locking area <NUM>. Protrusions <NUM>, e.g. detents, interfere with the outer diameter of the of a cam pin, e.g. pin <NUM>. For jaw member <NUM>, the continued axial translation of cam pin <NUM> forces a widening of the cam slot <NUM> in an elastic manner and creates an additional resistance force on the internal drivetrain, e.g. release pin <NUM> and shaft spring <NUM>. Once the cam pin <NUM> crests the inflection point on the protrusions <NUM>, it will snap into place behind the protrusion <NUM>, effectively locking the jaws in a closed position. Because a drive wire, e.g. drive wire <NUM>, operatively connected to jaw member <NUM> can only transmit limited compression, a user will not be able to translate sufficient force from a handle assembly, e.g. handle assembly <NUM>, distally to move cam pin <NUM> out of locking area <NUM> relative to the protrusions <NUM> to "unlock" the cam pin.

As shown in <FIG>, another embodiment of a jaw member <NUM> is shown. Jaw member <NUM> is similar to jaw members <NUM> in that it can be used in the jaw assembly <NUM> and the distal clip assembly <NUM>. Jaw member <NUM> also includes a distal end effector similar to distal end effector <NUM>. The main difference between jaw member <NUM> and jaw member <NUM> is that jaw member <NUM> includes a cam slot <NUM> in a proximal portion <NUM> of the jaw member <NUM> having a locking neck <NUM> formed by a tapered portion <NUM>, e.g. a triangular ramp, having a lip <NUM>. A proximal locking area <NUM>, similar to locking area <NUM>, is defined by the locking neck <NUM> proximally from the lip <NUM>. This geometry allows an easier transmission of axial force to normal force on the internal walls of cam slot <NUM>, requiring less force to initiate locking. The lip <NUM> positioned distally relative to the proximal locking area <NUM> will also prevent axial movement of a cam pin, e.g. cam pin <NUM>, after locking is achieved.

With reference now to <FIG>, another embodiment of a jaw member <NUM> is shown. Jaw member <NUM> is similar to jaw members <NUM> in that it can be used in the jaw assembly <NUM> and the distal clip assembly <NUM>. Jaw member <NUM> also includes a distal end effector similar to distal end effector <NUM>. The main difference between jaw member <NUM> and jaw member <NUM> is that jaw member <NUM> includes a cam slot <NUM> in a proximal portion <NUM> of the jaw member <NUM> having a locking neck <NUM> formed by a tapered portion <NUM>, e.g. a triangular ramp, terminating in a slot <NUM>. This open contour creates a cantilever lock arm <NUM> on the bottom wall of cam slot <NUM>. This results in a decreased force required to lock the clip, and results in a higher rate of successful locking in instances where the jaw members <NUM> are not perfectly parallel to each other, as deflection in the cantilever lock arm <NUM> can accommodate some axis offset of the jaw members <NUM>. A proximal locking area <NUM>, similar to locking area <NUM>, is defined by the locking neck <NUM> and positioned proximally from the tapered portion <NUM>.

As shown in <FIG>, another embodiment of a jaw member <NUM> is shown. Jaw member <NUM> is similar to jaw member <NUM> in that it can be used in the jaw assembly <NUM> and the distal clip assembly <NUM>. Jaw member <NUM> also includes a distal end effector similar to distal end effector <NUM>. The main difference between jaw member <NUM> and jaw member <NUM> is that jaw member <NUM> includes a cam slot <NUM> in a proximal portion <NUM> of the jaw member <NUM> having a locking neck <NUM> formed by a slope reversal on a proximal portion <NUM> of the cam slot <NUM>. In other words, instead of a proximal axis P of proximal portion <NUM> being parallel to a longitudinal axis A of a catheter body, e.g. catheter body <NUM>, proximal axis P is angled radially outward relative to axis A resulting in a locking force due to cantilever deflection. In this instance, the user will feel a gradual increase in feedback force, and then a sudden decrease. Once a cam pin, e.g. second pin <NUM>, has crested an inflection point <NUM> of the pin track (again, relative to the longitudinal axis of the clip body, which is parallel to longitudinal axis A of catheter body at rest) the slope direction changes and begins to force the clip open ever so slightly (<NUM>-<NUM> degrees of angulation between jaws. Subsequent unlocking of the jaw members <NUM> would require equal distal movement of the cam pin relative to a pivot pin, e.g. first pin <NUM>, which is prevented by the spring force required to pass the cam pin over the inflection point during distal translation. Again, an elongate drive wire, e.g. drive wire <NUM>, will not be able to transmit sufficient compressive force to actuate the cam pin distally, effectively locking the clip. The cam slot <NUM> of jaw member <NUM> has the as the added benefit of accommodating some amount of tissue thickness between the jaw members <NUM> without incurring bending stress in the jaw members <NUM>.

With reference to <FIG>, alternative embodiments of distal clip assembly <NUM> and proximal delivery catheter <NUM> are shown. In distal clip assembly <NUM> and proximal delivery catheter <NUM>, a release pin housing <NUM>, a release pin <NUM> and jaw adapter yoke <NUM> are used instead of release pin housing <NUM>, release pin <NUM> and jaw adapter yoke <NUM>. Otherwise, the other components of delivery catheter <NUM> and distal clip assembly <NUM> are the same as those of delivery catheter <NUM> and distal clip assembly <NUM>. Release pin housing <NUM> includes only one crimped portion <NUM> about release pin <NUM> to mechanically connect release pin <NUM> to housing <NUM> for common axial translation along and rotation about a longitudinal axis A defined by elongated catheter body <NUM>. In order to drive shaft spring <NUM> in the proximal direction upon firing, a proximal facing surface <NUM> of release pin housing <NUM> interferes with the annular portion by way of abutment. As shown in <FIG>, the pin housing <NUM> drives axially in a proximal direction and the proximal facing surface <NUM> abuts a distal facing surface <NUM> of annular portion <NUM> of shaft spring <NUM>, releasing flanges <NUM>. In an un-fired position, release pin housing <NUM> nests within the inner diameter of yoke <NUM>. In order to transmit torque from the release pin housing <NUM> to yoke <NUM> in an un-fired position, an outward extending flange <NUM> of release pin housing <NUM> engages with a slot <NUM> on the perimeter of the yoke <NUM>, as shown in <FIG>. Similar to release pin housing <NUM>, the control wire <NUM> is welded to the release pin housing <NUM> in order to drive the release pin housing <NUM> axially along and rotate the release pin housing about axis A. Release pin <NUM> is similar to release pin <NUM> in that release pin <NUM> has distal and proximal portions separated by a neck <NUM>.

Claim 1:
A device (<NUM>) for applying a hemostatic clip assembly, comprising:
a proximal delivery catheter (<NUM>) including a proximal handle assembly (<NUM>), an elongated catheter body (<NUM>) defining a longitudinal axis (A) and extending distally from the proximal handle assembly (<NUM>), a drive wire (<NUM>) movably positioned within the elongated catheter body (<NUM>), a release pin assembly coupled to a distal end of the drive wire (<NUM>), the release pin assembly including a release pin (<NUM>) and a release pin housing (<NUM>) positioned outward from the release pin (<NUM>), and a shaft spring (<NUM>) positioned outward from the release pin housing (<NUM>), wherein the shaft spring (<NUM>) includes an annular portion (<NUM>), wherein the release pin housing (<NUM>) is configured and adapted to interfere with the annular portion (<NUM>) of the shaft spring (<NUM>) upon proximal translation of the release pin housing (<NUM>); and
a distal clip assembly (<NUM>) removably connected to the distal end of the elongated catheter body (<NUM>), wherein the proximal delivery catheter (<NUM>) is configured and adapted to transmit linear motion along the longitudinal axis (A) and torsion about the longitudinal axis (A) to at least a portion of the distal clip assembly (<NUM>) characterised in that:
the annular portion (<NUM>) of the shaft spring (<NUM>) is positioned around the release pin housing (<NUM>).