HK1116375B - Transseptal catheterization assembly and methods - Google Patents

Description

Interatrial septum catheter assembly and method

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the patented range of U.S. provisional application No.60/800854, filed on 17.5.2006, which is hereby incorporated by reference as if fully set forth herein.

Technical Field

The present invention relates to assemblies and methods for penetrating or piercing tissue within the body, including, for example, interatrial septum access systems and methods for accessing the left atrium from the right atrium by crossing the fossa ovalis. In particular, the present invention is directed to medical devices used with catheter assemblies in cardiac procedures, such as atrial septum puncture, which require tissue puncture, or penetration. More particularly, the present invention relates to an improved manual assembly and method that combines several separate instruments used in transseptal catheter procedures, including a sheath, a dilator, and a needle assembly (e.g., including a penetrating instrument and a stylet).

Background

The human heart includes the right ventricle, right atrium, left ventricle, and left atrium. The right atrium is in fluid communication with the superior vena cava and the inferior vena cava. The tricuspid valve separates the right atrium from the right ventricle. The right atrium is separated from the left atrium by the septum of the atria.

A wide variety of diagnostic and therapeutic techniques have been developed in which a catheter is advanced transluminatively into different lumens and across the valves of the heart within a guide sheath or over a guide wire, with the most difficult lumen of the heart accessed with the catheter being the left atrium. Access to the left atrium through the pulmonary artery is not possible. Access from the left ventricle is difficult, may lead to and may present difficulties in achieving stable catheter positioning. Thus, the most common method of electrophysiology in which to gain access to the left atrium is through the puncture of the interatrial septum.

The results of left atrial access may be both diagnostic and therapeutic. One therapeutic use is electrophysiology, e.g., ablation of the left atrium. Catheter ablation involves the placement of energy (typically RF) through a catheter to different locations of the heart in order to eliminate inappropriate electrical pathways that affect heart function. When these locations are in the left atrium, the catheter itself through which the RF generator is placed is typically placed through the transseptal catheter.

In most cases, the transseptal catheter procedure is simplified with three separate septal tools, a sheath, a dilator, and a needle. For example, FIG. 1 shows details of the distal end of a current atrial septum tool, which includes: sheath 10 and sheath hub 12; a dilator 14 and a dilator hub 16; and a needle assembly 22; it includes a needle 18 and a needle hub 20. Conventional interatrial septum piercing catheters follow a number of steps. First, a guide wire is introduced into the femoral vein (or other selected pathway) and controlled to the Superior Vena Cava (SVC). Second, the sheath 10, typically with a dilator disposed therein, is inserted over the distal end of the guide wire and advanced to the SVC. At this time, the guide wire is removed. Third, the needle assembly 22 (possibly including a stylet) is advanced through the lumen of the dilator 14 until the distal end of the stylet 24 or needle 18 is just within the distal end of the dilator 14. The stylet 24 typically extends a portion beyond the distal end of the needle 18.

In most cases, the physician visually determines the point at which the stylet 24 and/or needle assembly 22 is just within the distal end of the dilator 14 by examining the separation between the distal end of the dilator hub 14 and the distal end of the needle hub 20 (distance "X" in fig. 1). Based on experience, it can typically be appreciated that the stylet 24 is in place when the dilator hub 16 and the needle hub 20 are separated by the physician's "two finger width". It is clear that this method is an approximation of an inaccurate position while providing itself with adjustment errors and difficulties. Alternatively, the physician may use x-ray techniques to verify the position of the stylet 24 or needle 18. However, this approach adds expense and complexity to the procedure.

Once the needle assembly 22 is deemed in place, the stylet 24 is typically removed from the lumen of the needle 18 and discarded, at which point the physician advances the needle assembly 22 forward until the distal end of the needle 18 is just within the distal end of the dilator 14. This distance can also be visually confirmed and approximated by checking the spacing between the needle hub 20 and the dilator hub 16, as shown in fig. 1. In addition, physicians may use other sophisticated diagnostic methods, such as x-ray techniques.

In this position, with the needle 18 still contained within the distal end of the dilator 14, the assembly 22 is pulled along the medial wall of the right atrium until the oval fossa is approached. The physician then advances the needle assembly 22 forward through the dilator 14 to puncture the septal wall, and when the puncture is approved, the dilator 14 and sheath 10 can then be advanced through the septal wall beyond the needle assembly 22 and into the left atrium.

In addition to the clinical recognition of the many procedures that require access to the left atrium, there is significant room for improvement in the actual access techniques and mechanisms designed to simplify such access. In addition to the risks associated with conventional cardiac catheterization, a number of risks are inherent in atrial septal puncture catheterization. For example, the main risk arises from the use of known interatrial septum devices, typically having a puncture device or needle, which may be accidentally exposed during the procedure. To this end, it is desirable to provide a puncture assembly in which the puncture device, referred to in the present application as a needle assembly, is safely maintained in a substantially fixed position within the dilator until the assembly is positioned at the puncture site of the septum.

Furthermore, the known assembly is cumbersome and difficult to operate. Thus, a significant disadvantage of current interatrial septum tools is that the tool is actually three separate components that operate independently of one another. This independence introduces significant difficulties for the user, who must either control them all independently, manually by the user, or remain in place. It would be highly desirable to provide an assembly combining these elements for coordination control, with additional mechanical safety features to provide improved safety and utility in connection with approved medical procedures. In particular, it is desirable to have a process for mechanically correctly positioning the needle, dilator, sheath and stylet during the procedure while also providing safety features to avoid unnecessary punctures and similar errors during the procedure.

Disclosure of Invention

The design of current interatrial septum tools is improved in embodiments of the present invention by including an additional safety mechanism and a predetermined advancement mechanism in an easy-to-use mating handle assembly to improve and simplify known interatrial septum procedures. Embodiments of the invention may include any number or combination of the following design aspects. For purposes of illustration, the present invention is described in terms of a transseptal puncture procedure, but it is contemplated that the invention is suitable and useful for any application where access to body tissue is to be provided by a catheter-type mechanism and puncture or penetration associated with any particular medical procedure.

Unitary handle assembly

Throughout the interatrial septum procedure, conventional tools and devices require the physician to maintain control over a plurality of physically separate devices, typically spaced apart from each other by a given distance. Importantly, further means of holding the devices relative to each other is necessary throughout a particular procedure. The present invention provides a cooperating handle assembly that is configured to allow easy and efficient operation of the various assemblies, while also providing a means for easily controlling the position of the components. When all the elements are put together, the result is a single handle assembly that is easy to operate. The specific parts of the handle assembly will be briefly discussed below.

Stylet stop mechanism

A stylet is typically used to assist in the advancement of the needle into the dilator. The stylet also functions to prevent buckling of the needle. The stylet typically extends beyond the distal portion of the needle assembly. The present invention includes a mechanical stylet stop device near the distal end of the dilator, or within the control mechanism, to prevent advancement of the needle until the stylet is removed. In addition, when the distal tip of the stylet reaches the distal end of the dilator, the stopper can be pushed back over the stylet, out of the needle. This feature prevents inadvertent advancement of the stylet outside the dilator. This stop arrangement also eliminates the need for the physician to visually measure the distance between the needle hub and the dilator hub, thus simplifying and improving the reliability of the interatrial septum procedure. In use, the stylet is typically removed from the assembly after the needle is advanced to the dilator.

Needle stop mechanism

After the stylet is removed, the needle is advanced through the sheath and the dilator until the distal end of the needle is just within the distal end of the dilator. The present invention provides a stop mechanism to provide tactile feedback to the physician when the needle reaches this point. This mechanical stop also prevents inadvertent advancement of the needle outside the dilator during use, which could injure the patient. For example, in fig. 2, this feature comprises an extension of the needle hub that is configured to include a spacer having a length (X) that corresponds to the distance the needle extends from the dilator at the distal end of the assembly when fully extended. The needle stop mechanism is held in place by a locking mechanism that can be moved by a button or other actuation means.

Needle advancing mechanism

After reaching the desired location for the puncture, the physician may actuate a button mechanically connected to the needle stop. The button then enables the needle to advance beyond the mechanical stop. This feature enables the needle to be advanced to extend beyond the dilator under the control of the physician. In any event, the maximum distance that the needle may move depends on the size of the needle stop mechanism.

Sheath/dilator advancing device

When the septal puncture is completed, and after the needle is advanced through the tissue, the hand-held device preferably includes an additional mechanism to facilitate advancement of the sheath and dilator into the left atrium. One embodiment of this concept utilizes an extension on the distal end of the needle hub that can push the sheath and dilator hub forward. This enables the physician to advance the dilator and sheath over the needle with greater stability and control.

In accordance with the present invention, these features and mechanisms are combined to provide an improved engagement handle assembly for use in transseptal catheterization procedures utilizing a sheath assembly, a dilator assembly, and a needle assembly, including a sheath hub, a dilator hub removably connected to the sheath hub, a needle hub removably connected to the dilator hub, and a needle advancement mechanism adapted to be coupled to the needle assembly such that the needle advancement mechanism can permit the needle assembly to be selectively advanced from a position within the dilator to a position outside of the dilator.

Furthermore, the present invention provides a method of manufacturing a control assembly comprising the steps of: providing a sheath hub, a dilator hub, and a needle hub; removably connecting the dilator hub to the sheath hub; at least partially disposing the needle assembly within the needle hub; and attaching a needle advancement mechanism to the needle assembly such that the needle advancement mechanism allows selective advancement of the needle assembly from a position within the dilator to a position outside of the dilator.

Additionally, the present invention provides a method for transseptal catheterization using a manual assembly having a detachably connected sheath hub, dilator hub, and needle hub, comprising the steps of: a placement needle assembly operably connected to the needle displacement mechanism proximate a target region of tissue; advancing the needle assembly by actuating the needle displacement mechanism; piercing a target area of tissue with a needle assembly; separating the dilator hub from the needle hub; the dilator hub is advanced while the distal end of the dilator passes through the punctured tissue area.

The present invention provides many advantages, including, for example, intuitive means, interlocking, proximal operation that organizes the elements and makes them easy to control. The present invention improves current interatrial septum puncture catheter operation by two points: (1) safely and reliably positioning the tip of the needle within the dilator; and (2) reduce the complexity of the procedure by simplifying the proximal end of the current tool set, enabling the physician to concentrate on other aspects of the procedure. The present invention includes the additional advantage of incorporating a mechanical stop to prevent inadvertent advancement of the needle. A further convenient safety feature comprises a release button for the advancement of the needle.

The foregoing and other aspects, features, details, and utilities of the present invention will be apparent from reading the following description and claims, and from referencing the accompanying drawings.

Drawings

Figure 1 identifies the elements of three common mechanisms currently used in atrial septum surgery, including a sheath, a dilator, and an assembly including a stylet. The needle assembly is disposed within the lumen of the dilator. Both the dilator and the needle assembly are placed within the lumen of the sheath.

Fig. 2 is a view of an improved handle assembly according to a first embodiment of the present invention. Hub member having a combination sheath, dilator and needle assembly for use in transseptal catheter procedures and a needle/stylet stop mechanism between the dilator hub and needle

FIG. 3 is a perspective view of the handle assembly of FIG. 2 showing the elliptical cross-sectional shape of the various hub assemblies.

Fig. 4 is a view of the embodiment of fig. 2 and 3, wherein the joined hubs have been separated while the needle hubs have been advanced to reach the needle stop assembly.

FIG. 5A shows a perspective view of an improved handle assembly according to a second example of the present invention.

Fig. 5B shows a view of a second embodiment of the invention in which the joined hubs have been separated while the needle hubs have been advanced a predetermined distance forward thus moving the stylet a corresponding distance in the opposite direction.

FIG. 6A shows a perspective view of an improved handle assembly according to a third example of the present invention.

Fig. 6B is a view of a third embodiment of the present invention, wherein the bonded hubs have been separated.

Fig. 6C is a view of a third example of the invention in which the needle hub has been advanced to abut the needle stop mechanism, thereby extending the tip of the needle beyond the distal tip of the sheath and/or dilator.

Fig. 7A shows a perspective view of an improved handle assembly according to a fourth example of the invention having a safety latch to prevent inadvertent advancement of the needle hub.

Fig. 7B shows a view of a fourth embodiment of the invention in which the bonded hubs have been separated while the needle hubs have been advanced a predetermined distance to extend the distal tip of the needle beyond the distal tip of the sheath and/or dilator.

FIG. 8A shows a perspective view of an improved handle assembly in accordance with a fifth embodiment of the present invention.

FIG. 8B shows a view of the handle assembly according to a fifth embodiment of the present invention where the combined hub has been separated while both the dilator/sheath advancement mechanism and the needle advancement mechanism are shown in their fully advanced positions.

Fig. 9A shows a perspective view of an improved handle assembly according to a sixth embodiment of the present invention with additional features of the shaft or dilator bending mechanism and a needle position indicator.

FIG. 9B shows a view of an improved handle assembly according to a sixth embodiment of the present invention in which the combined dilator and needle hub have been separated.

FIG. 10A shows a perspective view of an improved handle assembly having three hub assemblies and a single spacer between the dilator and the needle hub according to a seventh example of the present invention.

Fig. 10B shows a perspective view of an improved handle assembly in accordance with a seventh embodiment of the present invention, wherein the coupled hubs have been separated to further expose the presence of the stylet stop/displacement mechanism.

Fig. 11A shows a perspective view of an improved handle assembly according to an eighth example of the invention having three hub assemblies that are removably mounted to one another by two button/latch assemblies.

FIG. 11B shows a view of an improved handle assembly according to an eighth embodiment of the present invention, where the bonded hubs have been separated.

Fig. 12A shows a perspective view of an improved control according to a ninth embodiment of the present invention having three integrated hub assemblies and an elongated operative portion disposed between the needle hub and the dilator hub.

FIG. 12B shows a view of an improved handle assembly in accordance with a ninth embodiment of the invention in which the combined dilator and hub have been separated while the needle advancing mechanism is in its advanced position.

FIG. 13A shows a perspective view of an improved handle assembly according to a tenth embodiment of the present invention having three hub assemblies mounted by snap-fit snaps and having an outer three-way valve assembly mounted to a needle assembly by a flexible tube.

FIG. 13B shows a top view of the improved handle assembly according to a tenth example of the invention, identifying the toothed, or indented, regions on the sheath and dilator hub for increased effectiveness, and a lateral needle locking mechanism for actuating the needle assembly.

FIG. 13C shows a view of the improved handle assembly according to the first addressed embodiment of the invention, in which the incorporated hubs have been fully separated while the needle advancing mechanism is in its retracted position.

Fig. 13D and E show cross-sectional views of a needle hub assembly of a tenth embodiment, identifying a spring-biased needle advancement mechanism and also a transverse spring-biased needle lock button.

Detailed Description

The present invention relates to an improved manual assembly and method for combining multiple discrete instruments for use in transseptal catheter procedures, including sheaths, dilators, and needle assemblies (e.g., including a puncture device and a stylet). The manual assembly provides a combined component that reduces overall complexity and increases the safety of the transseptal catheter procedure.

As shown in FIG. 1, a typical transseptal catheter procedure uses at least three separate common elements, namely a sheath 10, a dilator 14, and a needle assembly 22 including a stylet 24. The needle assembly 24 is disposed within the lumen of the dilator 14. Both the dilator 14 and the needle assembly 22 are disposed within the lumen of the sheath 10.

The present invention is directed to an embodiment that combines three discrete components into a manual assembly 100 having several structural and operational advantages that increase the safety and convenience of use. The manual assembly is configured for use with known catheterization assemblies, such as those used in atrial septal procedures, which typically include a sheath, a dilator, and a puncture assembly, such as a needle assembly. Generally, the present invention comprises, in combination, a sheath hub 102, a dilator hub 104, and a puncture assembly hub 106 (only one needle hub for purposes of example herein).

The hubs, which together comprise the manual assembly 100, are jointly configured and removably connected by mechanical means such as latches, biased latches, snap-fit assemblies, or any similar removable connection known to those skilled in the art. The manual assembly also includes a needle advancement mechanism 108 that allows selective advancement to different positions, including a retracted position within the distal end of the dilator and an extended position outside of the dilator for the puncture procedure. The needle advancement mechanism 108 may be a sliding mechanism, a lever mechanism, a roller mechanism, a plunger mechanism, or any other mechanism known to those skilled in the art.

The needle advancing mechanism 108 may also include a locking mechanism to securely hold the needle in a desired position, either retracted or extended, during use. In addition, the manual assembly 100 may also include at least one spaced apart mechanism to maintain the different conditions of the assembly, such as the spike assembly, in predetermined positions during use. In addition, the manual assembly may also include additional components such as a one-way, two-way, or three-way valve for the introduction of fluids, such as contrast or saline fluids, or for pressure monitoring and safety devices. The manual assembly may also include a safety mechanism, such as a stylet retraction rod, to further arrest unwanted damage during surgery.

Materials for manufacturing the hand-operated components are well known to the skilled person and include, for example, injection moldable biocompatible plastics and the like. Specific materials considered suitable include polyetheramides (commercially available under the trade name PebaxTM), polyurethanes, polycarbonates, ABS, and polymers with similar properties.

Various aspects of the invention are described in detail below with reference to the figures for purposes of example. It is contemplated that virtually any of the individual components discussed below in accordance with the present invention may be included in any combination.

For example, fig. 2, 3 and 4 depict an improved manual assembly according to a first embodiment of the present invention. The manual assembly has a hub assembly incorporating a sheath 102 for use in atrial septum procedures, a dilator 104 and a needle assembly 106. The hub assembly of each of these components is preferably prefabricated with a corresponding removably mountable locking mechanism (not shown). The locking mechanism includes, for example, a spring or lever biased latch for detachable coupling. The set also has a two-position adjustable valve 114 disposed within the needle hub assembly 106. At least one of the hub assemblies also includes an orientation member 116, such as a tab, that serves to visually identify the orientation of the particular assembly within the body and to help maintain the proper orientation of the member during the atrial septum procedure. The hub assemblies themselves may also be configured to allow visual identification of the orientation of the assemblies within the body, for example, in the shape of an oval cross-section (as shown in FIG. 3).

In addition, the first embodiment of fig. 2, 3 and 4 includes a needle stop mechanism 118 disposed between the dilator hub 104 and the needle hub 106. The needle stop mechanism 118 is designed to the position shown in fig. 2 with the needle contained at a predetermined location within the distal end of the dilator. In the default position, the needle stop mechanism 118 is removably coupled to the dilator hub 104 and the needle hub 106 and maintains a predetermined distance between the hubs corresponding to the desired distance between the distal end of the dilator and the distal end of the needle assembly. The needle stop mechanism 118 is removably coupled to the needle hub 106 by a latch assembly 110 having a button 108 disposed on an outer surface of the needle hub 106. As shown in fig. 2 and 3, to advance the needle toward the distal end of the dilator, the physician (or any user) simply actuates the needle advancement mechanism 110, such as by pressing the button 108. When this knob is pressed, the needle hub is released from the needle stop mechanism 118 and the dilator hub 104, thus allowing the needle assembly within the dilator to advance a maximum distance corresponding to the distance between the needle stop interface on the needle stop mechanism 118 and the distal end of the needle hub (represented by distance "X" in fig. 2). This mechanism 118 provides for safe operation by preventing movement of the needle assembly unless required by the user while also providing for precise movement to achieve the desired insertion location when the needle hub 106 is advanced to the point where the distal end 122 abuts the needle stop interface 120.

The sheath hub 102 and dilator hub 104 also have corresponding snap-lock features that enable the two hub assemblies to be temporarily coupled. Fig. 2 and 3 show the dilator and the hub in a locked position. After the puncturing procedure is performed by the needle 128, as shown in FIG. 4 (or at any other desired stage of the procedure), these assemblies may be separated from the needle stop assembly and from each other to enable insertion of either or both of the dilator and sheath across the punctured interatrial septum (see FIG. 4).

Fig. 5A and B depict an improved handle assembly according to a second embodiment of the present invention. The handle assembly 200 has a hub assembly incorporating a sheath 202, dilator and needle assembly 206 for use in atrial septum procedures. Each of these hub assemblies is preferably prefabricated with a corresponding removably mounted locking mechanism (not shown). For example, the locking mechanism may include a snap-fit assembly, or a lever-biased latch for detachable coupling. The assembly also has a two-way or three-way adjustable valve 208 disposed within the needle hub assembly 206. At least one of the hub assemblies also includes an orientation member 210, such as a tab, that serves to visually identify the orientation of the particular assembly within the body and to help maintain the proper orientation of the member during the interatrial septum procedure.

In addition, the dilator hub 204 and the needle hub 206 are separated by at least one removable spacer 212. Two shims 212 are present in this particular embodiment, a first shim 214 being positioned adjacent the dilator hub 204 and a second shim 216 being positioned near the needle hub 206 at its distal end. The first spacer 214 is configured to allow the stylet 218 to be inserted a predetermined distance toward the distal end of the dilator 220 (see fig. 5B). It is also contemplated that the stylet may be removed and, thus, removal 228 of the first spacer 214 will enable advancement 222 of the needle to the first predetermined position. In the instance where the stylet 218 is not removed, removal of the first spacer 214 and subsequent advancement 222 of the needle hub 206 will cause the stylet to extend out of the distal end of the dilator (an often undesirable action). In addition, the second spacer 216 can be removed, in which case the needle hub 206 can be advanced a predetermined distance forward toward the distal end of the dilator. When the second spacer is removed, the needle assembly may be advanced into a puncture position outside the distal end of the dilator for puncture of the interatrial septum.

The sheath hub and dilator hub shown in fig. 5A and B also have corresponding snap-lock features (not shown) that enable the two hub assemblies to be temporarily coupled. As shown in FIG. 5B, after the puncturing procedure is performed (or at any other desired stage of puncturing), these assemblies 202, 204 may be separated from needle hub assembly 206, and from one another, to enable insertion of either or both of dilator 220 and sheath 226 across the punctured interatrial septum.

Fig. 6A-6C depict an improved handle assembly according to a third embodiment of the present invention. The handle assembly 300 has many similar parts to those described in fig. 2-4. In addition, the handle assembly 300 includes two push button release assemblies 302, 304, one for removably coupling the sheath hub and the dilator hub and the other for coupling the needle hub to the needle stop mechanism 312. In addition, the needle hub 310 may include a ridge 314 (in this case an annular ridge) around the distal portion of the needle hub, or any other structure that acts to sense resistance. This ridge 314 engages the proximal portion 312 of the needle stop mechanism and serves to provide a temporary stop for the needle assembly 310. Fig. 6A shows the assembly in the needle stop position. In use, needle assembly 310 is inserted into dilator 316 by pressing forward on assembly 310 to the desired predetermined position until protuberance 314 hits the proximal-most end of stop mechanism 312. In this way, the user receives a perceptible feedback that the needle is in the correct position. At a point where the user wishes to push the needle to extend beyond the puncture location of the dilator 316, he may pass the protuberance 314 through the proximal-most end 312 by doing so with greater pressure forward. In the embodiment of fig. 6A-6C, the shape of the hub assemblies themselves and the corresponding displacement of the button release mechanism serve two purposes, namely orienting the members for visual confirmation of the orientation of the particular assembly within the body and helping to maintain the correct orientation of the members during the atrial septum procedure. Also, these positioning members are of great value to the surgeon during procedures, such as atrial septal puncture procedures, where curved needles are often used.

FIG. 6B shows a side view of the various hub assemblies, separated from one another, similar to that shown above in the discussion of FIG. 4. Further, shown is the stylet 316 after use in conjunction with the assembly. Fig. 6B also shows a protuberance 314 that provides the benefit of additional sensory feedback during use by the surgeon. Fig. 6C also identifies the manual assembly in its fully advanced, or puncturing, position.

Fig. 7A-7B illustrate an improved handle assembly in accordance with a fourth embodiment of the present invention. The handle assembly 400 has a sheath 402 at the distal end of the assembly 400, a dilator hub 404 proximal to the sheath hub, and a needle hub 406 at the proximal end of the assembly, according to this embodiment. Each of these components is preferably prefabricated and may have a corresponding removably mounted locking/coupling mechanism. The assembly further includes a safety latch 408 as a needle locking mechanism of a predetermined length that is pivotally connected to the needle hub 406 such that when it is in a locked position (see fig. 7A), a distal end 410 of the safety latch 408 abuts a proximal-most end 412 of a front portion 414 of the needle hub 406. In this position, the needle assembly 406 prevents forward advancement, thus avoiding the distal end of the needle from extending beyond the distal end of the dilator 416. Such that the mechanism provides a safety feature of another configuration to avoid unnecessary punctures and the like when the assembly is used in the human body.

This fourth embodiment also includes a stylet displacement rod (not shown) disposed within the needle hub extending through the entire needle hub and terminating at the distal end portion. The length of the stylet displacement rod is preset so as to abut against a corresponding portion of the dilator hub 404 as the needle hub 406 is advanced toward the distal end of the assembly. The stylet displacement rod is slidably secured within the assembly such that when the needle hub 406 is advanced 418 and the displacement rod is held against the dilator hub 404, the stylet 424 is displaced a pre-set position in a direction 420 away from the proximal most end of the assembly 400. This mechanism serves to pull the distal end of the stylet 424 a preset distance from the dilator tip, and also provides safety benefits during operation of the assembly.

In addition, at least one of the hub assemblies also includes an orientation member 422, such as a tab, that serves to visually identify the orientation of the particular assembly within the body and to help maintain the proper orientation of the member during the interatrial septum procedure. The orientation feature may also be a visible mark, indentation, raised protrusion, or the like. In addition, different hub shapes may provide the necessary orientation information.

Fig. 8A-8B illustrate an improved handle assembly 800 according to a fifth embodiment of the present invention. In this embodiment, the handle assembly 800 has a combined hub assembly of a sheath 802, dilator 804 and needle assembly 806 for use in atrial septum procedures. The hub assembly of each of these components is preferably preformed with a corresponding removably mounted locking mechanism, such as a snap-fit assembly. The assembly may also include a two-way adjustable valve (not shown) disposed within the needle hub assembly 806. At least one of the hub assemblies also includes an orientation member 808, e.g., a tab, that serves to visually inspect the orientation of the particular assembly within the body and helps maintain the proper orientation of the needle and other components during the interatrial procedure.

A needle pusher 810 is located at the proximal end of the needle 806 and is operatively connected to a needle assembly 812 for advancing the needle through a dilator 814. The needle advancing assembly 810 may be plunger-type advancing while also being biased such that release of the mechanism results in automatic retraction of the needle assembly 812. The biasing mechanism may include a spring assembly (not shown). A dilator/sheath advancement mechanism 816, e.g., a button, is provided on the side of the needle hub 806 for advancing the sheath/dilator assembly 802/804 by the user during operation. In the advanced position 818, the sheath 806 and dilator hub 804 are separated from the needle assembly 812, enabling the sheath 820 and/or dilator 814 to extend beyond the needle assembly 812 and through the punctured tissue. This mechanism can increase safety in use.

Fig. 9A-9B illustrate a sixth embodiment of a handle assembly according to the present invention. The handle assembly according to this embodiment has a sheath hub 902 at the distal end of the assembly, a dilator hub 904 closest to the sheath hub 902, and a needle hub 906 at the proximal most end of the assembly 900. The assembly 900 also has a three-way adjustable valve 908 disposed within the needle hub 906 assembly. At least one of the hub assemblies includes an orientation member 910, such as a tab, that serves to visually identify the orientation of the particular assembly within the body while helping to maintain the orientation of the various components during the interatrial septum procedure.

The hub assembly of each of these components is preferably pre-formed to a corresponding shape and may have a corresponding removable mounting and locking mechanism 912. For example, the assembly includes a coupling mechanism 912 that removably couples the dilator hub 906 to the needle hub 906. The connection mechanism may be a latch mechanism having a corresponding button 914 for manual release of the hub connection.

The needle hub 906 also includes a sheath/dilator advancement mechanism on one side of the hub to manually separate the sheath/dilator to facilitate advancement of the sheath 918 and/or dilator over the needle assembly 920. When actuated, the sheath 902 and dilator hub 904 move distally, thus advancing the sheath 908 and dilator (not shown) over the needle 920 within the body. In addition, the needle hub 906 also includes a needle advancement mechanism 922, shown in FIG. 9 as a button on an upper portion of the needle hub 906. In the unbiased position, the needle assembly 920 is held in a predetermined position within the dilator. When the needle advancing mechanism is actuated, the distal portion of the needle assembly advances a predetermined portion of the distal end of the superdilator for use in puncturing the septum of the heart chamber. Although the embodiment shows a push button mechanism that advances the needle 920 and separates the hub assemblies, it is contemplated that any similar mechanism may be used, including, for example, a biased roller mechanism or a sliding mechanism. Furthermore, it is contemplated that these mechanical safety features may be similarly implemented by, in whole or in part, placing them within other hub assemblies.

The embodiment shown in fig. 9 preferably further includes a deflectable mechanism configured to control the adjustable sheath assembly. In this embodiment, the biasing mechanism 924 is shown as a roller mechanism on the hub 902. It is contemplated that any known similar adjustment mechanism may be used by the skilled artisan and may be placed in any suitable location on the device 900. It is also contemplated that similar devices associated with adjustable dilators or adjustable needles may be used.

In addition, the sixth embodiment may include a position indicator 926 (shown on the side of the sheath assembly in fig. 9). This position indicator is operably connected to the needle assembly 920 to provide visual confirmation of the position of the needle assembly 920 within the device, dilator, and/or sheath within the body. This indicator provides an additional safety measure by allowing the user to quickly confirm that the needle assembly 920, dilator and/or sheath are in the desired position. Although this position indicator 926 is shown on the sheath hub 902 in fig. 9, it is contemplated that it may be placed at any suitable location on the handle assembly 900. It is also contemplated that the position indicator 926 may be an electronic position indicator such as an LED display operatively connected to the needle assembly 920 to provide different visual signals depending on the position of the needle assembly 920. Additionally, indicator 926 may be an audible indicator operably connected to provide different signals depending on the position of the needle assembly.

Fig. 10A-10B depict a seventh embodiment of a handle assembly 1000 according to the present invention that includes the general elements of a sheath hub 1008, a dilator hub 1010, and a needle hub 1006. This embodiment combines the removable spacer 1002 described above with respect to fig. 5A-5B while also including the stylet stopper/displacement mechanism 1016 described above with respect to fig. 7A-7B. This embodiment thus provides the common benefit of preventing unwanted advancement of the needle assembly 1006 until the spacer 1002 is removed, while also providing for the stylet 1004 to be withdrawn a predetermined portion toward the proximal end of the assembly as the needle hub is advanced. As shown in fig. 10B, the stylet 1004 is removable from the assembly 1000.

11A-11B illustrate an eighth embodiment of a handle assembly 1100 according to the present invention. The embodiment of fig. 11 provides similar structural elements as described above for fig. 6, including common elements of the sheath hub 1102, dilator hub 1104, and needle hub 1106. In this embodiment, the sheath hub 1102 and the needle hub assembly 1106 are removably mounted to the dilator hub 1104 by a biased latch 1108. Also provided is a needle stop mechanism 1110. When a button shown on the side of the sheath hub 1102 is pressed, the sheath 1114 disengages from the dilator 1116, allowing independent adjustment of the dilator 1116 by the sheath 1114. Similarly, the embodiment shown in FIG. 11 provides a detachable stylet 1120 disposed within the needle hub 1106 and an adjustable valve 1122. In addition, as shown in FIG. 11A, an orientation indicator 1124 is included to identify the position of the sheath 1114, dilator 1116 and needle 1118 assembly during use.

Fig. 12A-12B depict a ninth embodiment of a handle assembly 1200 according to the present invention. This embodiment includes a sheath hub 1202, a dilator hub 1204, a needle hub 1206, and an elongated manipulation body 1208 disposed between the dilator hub 1204 and the needle hub 1206. This embodiment includes the offset latch assembly described above to removably couple the various hub assemblies together until separation is desired. This embodiment includes a slidable sheath/dilator advancement mechanism 1212 to separate the dilator 1204 and the sheath hub 1202 from the manipulation body 1208. When advanced, the advancing sheath 1214 and dilator 1216 pass beyond the needle 1218 into the left atrium. In addition, a needle advancing assembly 1220 is included within the needle hub assembly 1206 for advancing the needle assembly into the puncturing position when desired by the user. When actuated by the user, the needle hub as a whole can be advanced 1222 a distance until the distal end of the needle assembly abuts the proximal end of the elongate manipulation body 1208 (as shown in fig. 12B). This configuration also avoids extending the needle assembly too far outside the distal end of the dilator.

Fig. 13A-13C illustrate another preferred embodiment according to the present invention. In this embodiment, the handle assembly 1300 includes a sheath hub 1302, a dilator hub 1304, and a needle hub 1306. All three hubs are detachably connected to one another by a bonded snap-fit mechanism (e.g., 1328) that serves to hold the hubs together and further accurately position the hubs and thus the needle assembly 1312 for use with the sheath 1308, dilator 1310 and needle assembly 1312. To further facilitate this orientation, the handle assembly 1300 is shaped with a generally elliptical cross-section and also includes an orienting member 1314, such as a tab or other visible indicia.

As shown in fig. 13A-13E, the assembly 1300 further includes a needle stop mechanism 1316 configured to allow the needle assembly to be advanced a predetermined distance when the needle release mechanism 1318 is released. The needle stop mechanism 1316 is biased, in this case by a spring 1324, into a first, retracted, position (shown in fig. 13A). The needle release mechanism 1318 is operatively connected to the needle stop mechanism 1316 such that when the needle release mechanism 1318 is actuated (preferably in a direction as shown in fig. 13B and perpendicular to the direction of advancement of the needle), the needle hub and needle assembly can be advanced a predetermined distance, as given by the needle stop mechanism, to advance the needle the appropriate preset distance for the particular procedure. After the needle is removed from the dilator (or at least retracted a sufficient distance), the needle release assembly, upon a second actuation, or simply releasing the needle lock button, will reset the needle stop mechanism 1316 to the pre-operative state, which is accomplished by a second biasing mechanism, shown as spring 1326, which is operably connected to needle release 1318.

Fig. 13A also identifies an external three-way valve 1320 operatively connected to the needle hub 1306 by a flexible tube. The structure and flexible tubing of the valve provide a one-step benefit to the present invention, such as several rather than a single operating handle assembly to facilitate dispensing of fluids or other devices during a surgical procedure.

Although many embodiments of the present invention have been described above with a certain degree of particularity, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this invention.

All directional references (e.g., upper, lower, upward, downward, rearward, forward, left, right, leftward, rightward, top, bottom, above, below, vertical, horizontal, clockwise, and counterclockwise) are only used for identification purposes to aid the reader's understanding of the present invention, and do not create limitations, particularly as to the position, orientation, or use of the invention. A combined reference (e.g., mounting, coupling, connecting, etc.) is broadly established to also include intermediate members between a connection of elements and a relative movement between elements. Thus, the incorporated references do not necessarily indicate that those two elements are directly connected and in fixed relation to each other. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not limiting. Changes in detail or structure may be made without departing from the spirit of the invention as defined in the claims.

Claims (21)

1. A handle assembly for use in a transseptal catheter procedure utilizing a sheath assembly, a dilator assembly and a needle assembly, wherein the dilator assembly slides relative to the sheath assembly and the needle assembly slides relative to the dilator assembly, the handle assembly comprising:

a sheath hub;

a dilator hub removably connected to the sheath hub via a first latch;

a needle hub removably connected to the dilator hub via a second latch; and

a needle advancement mechanism adapted to be coupled to the needle assembly, wherein the needle advancement mechanism allows the needle assembly to be selectively advanced from a position within the dilator to a position outside the dilator.

2. The handle assembly of claim 1, further comprising a spacing mechanism adapted to maintain the needle assembly in a predetermined position within the dilator.

3. The handle assembly of claim 2, wherein the spacing mechanism comprises at least one removable spacer.

4. The handle assembly of claim 1, further comprising at least one orienting member on at least one of the sheath hub, the dilator hub, and the needle hub.

5. The handle assembly of claim 1, wherein the dilator hub is removably attached to the sheath hub by a latch or a button assembly.

6. The handle assembly of claim 1, wherein the needle hub is removably connected to the dilator hub by a latch, or a knob assembly.

7. The handle assembly of claim 1, wherein the needle advancing mechanism is a sliding mechanism.

8. The handle assembly of claim 1, wherein the needle advancing mechanism is a roller mechanism.

9. The handle assembly of claim 1, wherein the needle advancing mechanism is a lever mechanism.

10. The handle assembly of claim 1, wherein the needle advancing mechanism is a plunger mechanism.

11. The handle assembly of claim 1, wherein the needle advancement mechanism is disposed within the needle hub.

12. The handle assembly of claim 1, wherein the needle advancing mechanism includes a biasing device that retains the distal end of the needle assembly within the dilator.

13. The handle assembly of claim 1, further comprising a locking mechanism to prevent movement of the needle assembly.

14. The handle assembly of claim 1, further comprising a valve.

15. The handle assembly of claim 1, further comprising a stylet displacement mechanism configured to move the stylet in a direction opposite the needle assembly as the needle advancement mechanism advances.

16. The handle assembly of claim 1, further comprising a needle indicator.

17. The handle assembly of claim 1, further comprising a direction control mechanism operably connected to at least one of the sheath assembly, the dilator assembly, and the needle assembly.

18. A handle assembly as claimed in claim 5 or 6, wherein the latch is an offset latch.

19. A method of manufacturing a handle assembly comprising the steps of:

providing a sheath hub, a dilator hub, and a needle hub;

removably connecting the dilator hub to the sheath hub via a first latch;

removably connecting the needle hub to the dilator hub via a second latch;

placing the needle assembly at least partially within the needle hub;

a needle advancement mechanism is coupled to the needle assembly such that the needle advancement mechanism allows the needle assembly to be selectively advanced from a position within the dilator to a position outside of the dilator.

20. The method of claim 19, further comprising the step of spacing the needle assembly at a preset location within the dilator.

21. The method of claim 19, further comprising the step of locking the needle assembly.