The present disclosure relates to a device for compressing a stent, as needed with a prosthetic heart valve affixed thereto, as well as a system for loading a stent, as needed with a prosthetic heart valve affixed thereto, into a medical delivery system, in particular the tip of a catheter of a medical delivery system. The disclosure further relates to a method for loading a stent, as needed with a prosthetic heart valve affixed thereto, into a medical delivery system, in particular the tip of a catheter of a medical delivery system.
Medical technology has long since endeavored to occlude valvular defects such as, for example, aortic valve insufficiencies or aortic valve stenosis, by means of non-surgical, transarterial access; i.e. without requiring open heart surgery, with implantation by way of catheter. In the process, various different stent systems with various different advantages and disadvantages have been proposed, some which can also be inserted transarterially into the body of a patient via a catheter delivery system.
The terms “aortic valve stenosis and/or aortic valve insufficiency” as used herein generally refer to a congenital or acquired dysfunction of one or more cardiac valves. Such valvular disorders can affect any of the four cardiac valves, whereby the valves in the left ventricle or left chamber (aortic and mitral valve) are typically more affected than those on the right side of the heart (pulmonary and tricuspid valve). The dysfunction can be a constriction (stenosis), an incompetence (insufficiency) or a combination of the two (combined vitium).
Minimally-invasive forms of treatment have recently been developed which are in particular characterized by allowing the procedure to be performed under local anesthesia. One approach provides for using a catheter system to implant an expandable stent, to which a collapsible prosthetic heart valve has been affixed, into a human body. Such an expandable prosthetic heart valve can be guided via a delivery or catheter system to the implantation site within the heart through an inguinal artery or vein. After reaching the implantation site, the stent can then be unfolded. After unfolding, the prosthetic heart valve can be anchored in the respective blood vessel at least in an area close to the heart, for example with the aid of anchoring hooks. The actual prosthetic heart valve is usually positioned in the proximal area of the stent.
For example, the WO 2004/019825 A1 printed publication describes a heart valve stent for a heart valve prosthesis. This stent can be introduced into the site of implantation in the patient's heart via a medical delivery system to treat an aortic valve stenosis and/or aortic valve insufficiency in a minimally-invasive manner.
Known conventional systems for implanting a prosthetic heart valve introduce an expandable stent system transarterially/transfemorally or transapically into the body of the patient using a medical delivery system. This type of stent system consists for example of an expandable anchoring support (hereinafter also referred to as “cardiac valve stent” or simply “stent”), to which the actual prosthetic heart valve is affixed or can be affixed, preferably at the end region nearest the heart (proximal end).
The explanations disclosed herein with respect to a “stent system” are also applicable to a “stent”.
The term “medical delivery system” as used herein generally refers to a medical system with which a stent system can be advanced in minimally-invasive fashion to the site of implantation in the patient's heart, for example to treat an aortic valve stenosis and/or aortic valve insufficiency. In the present context, “minimally-invasive” means a heart-lung machine is not needed when performing the procedure on the anaesthetized patient such that not only can the medical procedure be performed at reasonable cost, but there is also less physical and psychological strain on the patient.
A medical delivery system usually comprises a catheter system by means of which a stent, as needed with a prosthetic heart valve affixed thereto in folded state, can be introduced into the patient's body in its folded state. For example, the medical delivery system can exhibit a catheter tip having at least one manipulatable receiving area at a proximal end section of the catheter system; i.e. closest to the heart. It is moreover conceivable for the medical delivery system to exhibit a handle at the distal end section of the catheter system; i.e. at the end section of the catheter system farthest from the heart and the catheter tip, with which the at least one receiving area of the caterer tip can be appropriately manipulated such that the expandable stent accommodated in the catheter tip, as needed with a prosthetic heart valve affixed thereto, can be incrementally released from the catheter tip according to a predefined or predefinable sequence of events.
In this disclosure, the expression “catheter system” means a system that can be inserted into a body cavity, duct or vessel. A catheter system thereby allows access by surgical instruments. The process of inserting a catheter system is catheterisation. In most uses a catheter system is a thin, flexible tube: a “soft” catheter system; in some uses, it is a larger, solid tube: a “hard” catheter system.
To introduce the stent system, the stent together with the prosthetic heart valve affixed as needed thereto, is loaded into the tip of the medical delivery system's catheter. In order to do so, the stent, as needed with the prosthetic heart valve affixed thereto, needs to exhibit a first predefinable shape in which the stent or the stent and the prosthetic heart valve affixed thereto is/are in a compressed or folded state. In its first predefined state, the stent, as needed with the prosthetic heart valve affixed thereto, exhibits a diameter which is essentially determined by the diameter of the catheter tip of the medical delivery system.
For the majority of patients undergoing treatment, it is preferable for the stent, as needed with the prosthetic heart valve affixed thereto, to have an outer diameter of approxi-mately 7.0 mm to approximately 5.0 mm in its first shape so that the stent system can be introduced with a 21F delivery system (given an external diameter of 7.0 mm) or with a 15F delivery system (given an external diameter of 5.0 mm).
After the stent system has been released from the catheter tip, in the implanted state respectively, the stent system exhibits a second predefined shape in which the stent or the stent and the prosthetic heart valve affixed thereto is/are in an expanded state. Depending on the patient being treated, it is preferable for the stent to exhibit a diameter of between 19.0 mm and 27.0 mm in its second shape and implanted state.
Thus, the first shape transitions to the second shape by a cross-sectional widening, wherein the stent stretches radially and presses against the vascular wall of a blood vessel near the heart and thus fixes a prosthetic heart valve affixed as needed to the stent at the site of implantation. The cross-sectional widening can be effected by a balloon system when the stent is implanted with the help of a so-called balloon catheter system.
On the other hand, it is also known from medical technology to construct the stent from a superelastic shape memory material which is designed such that the stent can transform from a temporary shape into a permanent shape under the influence of an external stimulus. The temporary shape thereby corresponds to the stent's first shape when the stent, as needed with the prosthetic heart valve affixed thereto, is in its folded state. The permanent shape corresponds to the stent's second shape when in its expanded state. An example of a suitable shape memory material would be nitinol, e.g., an equiatomic alloy of nickel and titanium.
Turning out to be disadvantageous with conventional systems for implanting a prosthetic heart valve as known to date, however, has been that not only the actual implantation of the stent, as needed with the prosthetic heart valve affixed thereto, but also the preparation needed for the implant procedure is relatively complicated, difficult and laborious. Apart from the complicated implanting of the stent, as needed with a prosthetic heart valve affixed thereto, to replace an insufficient native heart valve, for example, there is also the fundamental problem of the stent and/or the stent and a prosthetic heart valve affixed thereto being damaged when the stent, as needed with a prosthetic heart valve affixed thereto, is loaded into the tip of the catheter of the medical delivery system in preparation for the surgery. In particular with self-expanding stent systems, the stent, as needed with a prosthetic heart valve affixed thereto, has to be compressed so that it will then be in its first shape and be able to be introduced into the tip of the catheter of a medical delivery system. This subjects the stent to considerable compressive forces in order to overcome the self-expanding stent structure's expansion forces and achieve the desired reduction in cross-section.
Similar circumstances however also apply to stent systems which are implanted using balloon catheter systems.
In conjunction hereto, often likewise regarded as problematic is that when preparing for the implant procedure, the stent, as needed with a prosthetic heart valve affixed thereto, can often only be loaded into the tip of the catheter of a medical delivery system by an experienced perfusionist or by product specialists so as to avoid damaging the stent system and so that the stent system can be properly transformed into its defined first shape.
Without special compressing mechanisms or loading systems, the known systems are thus coupled with the fundamental risk of damage to the stent system or it not properly being transformed into its defined first shape, for example due to an oversight on the part of the perfusionist or product specialist or some other incident occurring during the compressing of the stent system. Damage which occurs when compressing the stent system or when loading the compressed stent system into the catheter tip of the medical delivery system are often not noted until the actual implant procedure is underway, for example when the positioning and/or fixing of the prosthetic heart valve at the site of implantation at the heart by means of the stent is imprecise, when the stent will not properly expand at the implantation site in the heart, or when it is for example deter-mined that the implanted prosthetic heart valve cannot or not adequately enough assume the function of the native heart valve to be replaced.
On the basis of the problems outlined above, the present disclosure relates to a device as well as a system for compressing a stent with which the stent, as needed with a prosthetic heart valve affixed thereto, can be readily compressed to a desired diameter, in particular without the risk of the stent and/or the stent and a prosthetic heart valve affixed thereto being damaged when compressed.
An embodiment of the present disclosure may provide a simplified method for loading a stent, as needed with a prosthetic heart valve affixed thereto, into the catheter tip of a medical delivery system, in particular wherein the proper loading of the stent into the tip of the catheter no longer depends to a significant extent on the finesse and experience of the given perfusionist or product specialist.
An embodiment of the present disclosure may include a device for compressing a stent, as needed with a prosthetic heart valve affixed thereto, whereby the device comprises a compressing mechanism and a gripping mechanism. The device according to the present invention allows for compressing a stent, as needed with a prosthetic heart valve affixed thereto, to a desired diameter. The term “desired diameter” means a diameter of the stent which allows a proper loading of the stent into the tip of a catheter.
The compressing mechanism of the inventive device is on the one hand configured such that the stent to be compressed can be at least partly accommodated inside the compressing mechanism. On the other hand, the compressing mechanism of the inventive device is designed to exert a compressive force radial to the stent at least on certain areas of the outer surface of the stent such that the stent's cross-section is reduced to a predefinable value at least at certain areas.
The device for compressing a stent, as needed with a prosthetic heart valve affixed thereto, comprises a gripping mechanism for forming a releasable connection with the stent to be compressed, and in particular with an end section of said stent. The gripping mechanism is thereby realized separately from the compressing mechanism and is axial displaceable to be at least partly accommodated within the compressing mechanism. The gripping mechanism comprises an actuating element attached to a claw for grasping the stent.
At least one, in particular externally actuatable clamping jaw is then provided in the interior of the compressing mechanism which is movable in the radial direction to set the internal cross-section diameter of at least one area of the compressing mechanism.
With respect to the specified disclosure, a system is further disclosed with which a stent, as needed with a prosthetic heart valve affixed thereto, can be loaded into a medical delivery system, in particular into the tip of a catheter of a medical delivery system. The system comprises a device for compressing the stent and a supplementary compressing mechanism for compressing the proximal end section of the stent. The supplementary compressing mechanism is configured analogously to the device's compressing mechanism.
To solve the cited second task, a method is disclosed to load a stent, as needed with a prosthetic heart valve affixed thereto, into a medical delivery system, in particular into the tip of a catheter of a medical delivery system, whereby the method comprises the method steps as specified in claim 35.
The explanations disclosed herein with respect to a stent are also applicable to a stent with a prosthetic heart valve affixed thereto.
Providing a gripping mechanism which is designed to create a releasable connection to the stent to be compressed, and in particular to an end section of the stent, may eliminate directly touching the stent by hand when compressing the stent or loading it into the tip of the catheter of the medical delivery system. In this respect, the risk of a contamination and damaging of the stent and/or the stent with the prosthetic heart valve affixed thereto can be avoided or reduced. Instead, to grasp the stent to be compressed, the claw of the gripping mechanism only comes into contact with those areas of the stent to be compressed provided for the purpose such that the risk of damaging the stent during grasping may be significantly reduced or eliminated.
Specifically, the gripping mechanism comprises a claw, or gripping forceps respectively, with which the stent to be compressed can be grasped, preferably at the end section of said stent. It is thereby preferable for the releasable connection between the claw and the stent to occur preferably at an end section of the stent at which the prosthetic heart valve is not sewn or to be sewn and which serves to connect to a fastening section in the catheter tip of the medical delivery system. This end section of the stent is usually the distal end section of said stent.
The terms “distal” and “proximal” as used herein are positional or directional identifiers for the stent, each referring to the stent in the implanted state. With a heart valve stent used for example to treat aortic or pulmonary valve insufficiency, the proximal end section of the stent thus faces the left or right chamber when the stent is in its implanted state.
The gripping mechanism further comprises an actuating element by means of which the claw can be manipulated accordingly so as to grasp the stent to be compressed. The gripping mechanism is thus suited to form a releasable connection with the stent to be compressed without the stent thereby needing to be touched by hand.
Since the gripping mechanism is axially displaceable when being received in the compressing mechanism, this ensures that the stent grasped with the claw of the gripping mechanism can be loaded into the compressing mechanism. Specifically, the compressing mechanism is designed such that the stent grasped by the gripping mechanism can be received within the compressing mechanism and can be displaced longitudinally relative the compressing mechanism. It is in this way possible to load a stent releasably connected to the claw of the gripping mechanism into the compressing mechanism such that the stent to be compressed is at least partly accommodated within said compressing mechanism.
The device thus allows the stent to be compressed to be loaded into the compressing mechanism, whereby the gripping mechanism only comes into contact with the areas of the stent so intended for the purpose.
The compressing mechanism is designed so as to exert a defined and radially-acting compressive force on at least one area of the stent accommodated in the compressing mechanism so that the cross-section of the stent to be compressed can in this way be reduced to a predefinable value at least at certain areas. To this end, at least one clamping jaw is provided in the interior of the compressing mechanism which is movable in the radial direction by appropriately manipulating the compressing mechanism in order to in this way adjust the internal cross-sectional diameter of the compressing mechanism to a predefinable value at least at one area of the compressing mechanism.
By having at least certain areas of the internal cross-sectional diameter of the compressing mechanism being able to be changed by the at least one actuatable clamping jaw, it is possible to have a defined compressive force act on the outer surface of the stent at least partly accommodated in the compressing mechanism. This compressive force counters the stent's tensioning force acting in the radial direction so as to overcome it and reduce the cross-section of the stent accommodated in the compressing mechanism to the value provided for the catheter tip of the medical delivery system according to a predefinable sequence of events.
Preferred embodiments of the disclosed solution are indicated in the dependent claims.
One preferred realization of the disclosed device provides for the gripping mechanism to comprise a guide sleeve in which the claw can be at least partly accommodated. In so doing, the claw should be movable relative the guide sleeve upon actuation of the actuating element. This provides an effective solution for realizing interaction of the gripping mechanism's actuating element with the claw in order to create a releasable connection between the gripping mechanism and the stent to be compressed in the compressing mechanism. Other embodiments of the gripping mechanism are also conceivable.
In order to have the gripping mechanism be accommodated at least partly within the compressing mechanism in defined manner, it is preferable for the guide sleeve to comprise at least one guiding element configured complementary to at least one of the guiding elements allocated to the compressing mechanism. For example, it is conceivable for at least one guiding element designated for the guide sleeve to be configured as a guide rail extending longitudinally to the guide sleeve.
It is hereby preferred when the at least one guiding element allocated to the compressing mechanism is configured as a guiding groove designed correspondingly complementary to the guide rail. The gripping mechanism accommodated in the compressing mechanism can thus be aligned relative to the compressing mechanism by the guiding element allocated to the guide sleeve on the one hand and the compressing mechanism on the other. The guiding elements extend preferably in the longitudinal direction to the guide sleeve, the compressing mechanism respectively, so that same allow a longitudinal movement of the gripping mechanism relative the compressing mechanism and thereby guide the gripping mechanism.
It is also conceivable for at least one guiding element allocated to the guide sleeve to be configured as a guiding groove and at least one guiding element allocated to the com-pressing mechanism to be configured as a guide rail. Other embodiments of the guiding elements designated for the guide sleeve, the compressing mechanism respectively, are likewise conceivable and covered by the present disclosure.
One preferred realization of the gripping mechanism provides for the gripping mechanism to comprise a retaining section arranged coaxially to the guide sleeve and connected to said guide sleeve. The retaining section preferably serves to receive the actuating element with which the claw of the gripping mechanism can be correspondingly manipulated. It is for example conceivable for the actuating element to comprise a preferably manually-actuatable pushbutton held in the retaining section and movable in the longitudinal direction of the gripping mechanism relative the retaining section and relative the guide sleeve.
The pushbutton can for example be connected to the claw of the gripping mechanism so that upon actuation of said pushbutton, the claw of the gripping mechanism moves in the longitudinal direction of the gripping mechanism relative the guide sleeve.
The present disclosure is however not limited to the specific embodiments in which the actuating element comprises a preferably manually-actuatable pushbutton. Rather, this would only be one possible realization of the actuating element for appropriately manipulating the claw of the gripping mechanism as needed.
In one preferred realization of the device, the claw for grasping the stent to be compressed comprises at least one and preferably three gripper arms, whereby fastening means are provided preferably on the first end section of the at least one gripper arm which are designed to create a releasable connection with the stent to be compressed. The number of gripper arms which the claw is to comprise should conform to the number of fastening means provided on the stent to be compressed and thereby serve to connect the stent to the catheter tip of a medical delivery system.
Usually the fastening means of the stent to be compressed are provided on the distal end section of the stent. Accordingly, the fastening means provided at the first end section of the at least one gripper arm are preferably designed to create a releasable connection with the distal end section of a stent to be compressed.
The fastening means provided on the at least one gripper arm should be designed complementary to a retaining section, the corresponding fastening means respectively, of the stent to be compressed. In particular, the fastening means provided on the at least one gripper arm are designed to form a releasable engagement with the retaining section, the corresponding fastening means respectively, of the stent to be compressed. For example, it is conceivable for the fastening means provided on the at least one gripper arm to comprise at least one projecting element, for example at least one hook-shaped element, which can be brought into releasable engagement with a retaining grommet of a stent to be compressed designed correspondingly complementary thereto.
Alternatively or additionally hereto, it is likewise conceivable for the fastening means provided on the at least one gripper arm to comprise at least one recess formed in the first end section of the gripper arm which can for example be configured in the shape of a preferably oblong grommet. This recess formed in the first end section of the gripper arm should thereby be able to be brought into releasable engagement with a projecting retaining element of a stent to be compressed designed correspondingly complementary thereto. Other embodiments are also conceivable for the fastening means provided at the first end section of the at least one gripper arm.
In order to achieve the corresponding manipulating of the claw upon actuation of the actuating element of the gripper means so as to enable a grasping of the stent to be compressed, a preferred realization of the device provides for the at least one gripper arm to comprise the above-mentioned fastening means at its first end section, whereby the at least one gripper arm is connected to the actuating element of the gripping mechanism by its second end section opposite its first end section. It is hereby in principle possible for the at least one gripper arm to be directly connected to the actuating element of the gripping mechanism by its second end section.
One preferred realization of the device however provides for the claw of the gripping mechanism to comprise a guide shaft, whereby the first end of the guide shaft is connected to the second end section of the at least one gripper arm, and whereby the second end of the guide shaft is connected to the actuating element of the gripping mechanism. The guide shaft can for example be configured as a cylindrical body.
The providing of a guide shaft connecting the at least one gripper arm to the actuating element of the gripper mechanism allows for a particularly secure manipulating of the gripper arms of the claw for grasping the stent to be compressed upon the actuating of the actuating element. Yet other solutions for connecting the at least one gripper arm to the actuating element of the gripping mechanism are also conceivable.
Preferred with the latter embodiment, in which the claw comprises a guide shaft in order to connect the at least one gripper arm to the actuating element of the gripper mechanism, is for the guide shaft to be accommodated within a guide sleeve provided for the gripping mechanism. Specifically, the guide shaft is to be accommodated within the guide sleeve such that the guide shaft together with the at least one gripper arm connected thereto is displaceable relative the guide sleeve. It is thereby further preferred for guide means to be provided to guide the guide shaft within the guide sleeve upon the displacing of the guide shaft relative the guide sleeve. Such guide means can for example be designed in the form of guiding surfaces.
A preferred embodiment of the device provides for the at least one gripper arm of the claw to be connected via its second end section to the guide shaft such that the at least one gripper arm protrudes from the guide shaft at an angle relative to the longitudinal direction of the guide shaft. In so doing, the at least one gripper arm and/or a connecting area between the second end section of the at least one gripper arm and the guide shaft are configured so as to be elastically deformable such that upon a displacement of the guide shaft relative the guide sleeve, the at least one gripper arm connected to the guide shaft is at least partly received in the guide sleeve by simultaneous radial deformation. In this embodiment, the gripper arms of the claw accordingly span outward like an umbrella when the guide shaft is moved away from the actuating element relative the guide sleeve. It is thereby effortlessly possible to form a releasable connection to the stent which exhibits different respective cross-sections in the uncompressed state with one and the same gripping mechanism.
On the other hand, this embodiment allows a precompressing of the stent after the releasable connection to the stent having been formed, and does so in that the guide shaft is displaced in the direction of the actuating element relative the guide sleeve, in consequence of which the umbrella-like stretched gripper arm contracts radially. Since a retaining element preferably provided on the distal end section of the stent is respectively connected to the respective first end section of the gripper arm, a displacement of the guide shaft relative the guide sleeve precompresses at least the distal end section of the stent. The precompressing of the distal end section of the stent is effected to a maximum diameter predefined or predefinable by the internal diameter of the guide sleeve. Accordingly, an internal diameter should be selected for the guide sleeve which reflects a desired precompressing of the distal end of the stent.
A preferred further embodiment of the device provides for the gripping mechanism to comprise a spring mechanism which interacts with the claw such that the claw can be spring-locked. It is hereby particularly preferred for the spring mechanism to comprise a spring, preferably a helical compression spring, arranged in the retaining section of the actuating element such that it pretensions the pushbutton of the actuating element against the guide sleeve. As noted above, it is preferred for the pushbutton to be designed as a manually-actuatable pushbutton accommodated in the retaining section of the gripper mechanism and movable relative the guide sleeve in the longitudinal direction of the gripper mechanism.
In the latter embodiment in which the gripper mechanism comprises a spring mechanism having a spring, in particular a helical compression spring, it is preferable for the pre-tensioning exerted by the spring on the pushbutton of the actuating element to be selected such that without impacting the compressive force exerted externally on the pushbutton, the claw—with the exception of the fastening means provided at the first end section of the at least one gripper arm—is accommodated completely within the guide sleeve. This configuration accordingly allows the claw, the at least one gripper arm of the gripper mechanism respectively, to grasp the stent to be compressed, as well as the precompres sing of the stent at least in certain areas.
In so doing, when the at least one gripper arm is driven out from the guide sleeve, said at least one gripper arm spans evenly in the radial direction. In order to achieve this, it is preferable to select the spring's stroke to be shorter than the length of the at least one gripper arm.
It is preferred for the compressing mechanism to comprise a funnel-shaped area on at least one end. Providing a funnel-shaped area simplifies the insertion of the stent to be compressed into the interior of the compressing mechanism configured as a hollow cylindrical body. The funnel-shaped area can further be accorded the function of precompressing the stent when the stent is being inserted into the compressing mechanism through the funnel-shaped area. Accordingly, at least the end of the compressing mechanism through which the stent to be compressed is inserted into said compressing mechanism is configured as a funnel-shaped area.
Additionally to the at least one funnel-shaped area at an end of the compressing mechanism, it is also preferred for the compressing mechanism to additionally comprise a clamping area aligned coaxially to the funnel-shaped area and connected to said funnel-shaped area. The stent to be compressed is at least partly accommodated in this clamping area after having passed through the previously-mentioned funnel-shaped area. The actual compression of the stent thereby occurs in the clamping area. Accordingly, the at least one externally-manipulatable clamping jaw, which is movable in the radial direction for adjusting the internal cross-sectional diameter of the compressing mechanism, is accommodated in the clamping area.
The clamping area of the compressing mechanism comprises a mechanism for actuating the at least one clamping jaw which can correspond to the mechanism of a clamping chuck. It is thus for example conceivable to provide a clamping area which functions according to the principle of traction.
With such a clamping area, the compressing mechanism can for example exhibit a tensioning screw accommodated in the clamping area which is rotatable about the longitudinal axis of the compressing mechanism relative the at least one clamping jaw and which interacts with the at least one clamping jaw such that upon a rotation of the tensioning screw, the at least one clamping jaw is displaced in the longitudinal direction of the compressing mechanism relative to a clamping cone accommodated in the clamping area. Such a mechanism enables the at least one clamping jaw to be manipulated by rotating the tensioning screw such that it can move in the radial direction relative to the longitudinal axis of the compressing mechanism so as to enable the internal cross-sectional diameter in the clamping area of the compressing mechanism to be set to a predefinable value.
Alternatively hereto, however, it is also conceivable for the compressing mechanism to comprise a tensioning screw accommodated in the clamping area or another similar tensioning element which is movable in the direction of the longitudinal axis of the compressing mechanism relative the at least one clamping jaw and interacts with the at least one clamping jaw such that upon the tensioning screw moving relative the at least one clamping jaw, the at least one clamping jaw is displaced in the longitudinal direction of the compressing mechanism relative a clamping cone accommodated in the clamping area. This type of mechanism likewise enables the at least one clamping jaw to be manipulated by moving the tensioning screw or tensioning element such that it can be radially moved relative the longitudinal axis of the compressing mechanism, thus allowing the internal cross-sectional diameter to be set to a predefinable value in the clamping area of the compressing mechanism.
The term “similar tensioning element” used herein means an element which is movable in the direction of the longitudinal axis of the compressing mechanism relative the at least one clamping jaw and interacts with the at least one clamping jaw such that upon the tensioning screw moving relative the at least one clamping jaw, the at least one clamping jaw is displaced in the longitudinal direction of the compressing mechanism relative a clamping cone accommodated in the clamping area.
Specifically, in the latter embodiments of the clamping area, the at least one clamping jaw is to interact with the clamping cone such that upon a movement of the at least one clamping jaw into the clamping cone, the at least one clamping jaw is moved in the radial direction relative to the longitudinal axis of the compressing mechanism, relative to the longitudinal axis of the clamping area of the compressing mechanism respectively. As already noted above, the movement of the at least one clamping jaw into the clamping cone can be effected by rotating the tensioning screw or moving the tensioning screw in the direction of the longitudinal axis of the compressing mechanism. The clamping jaw can be moved out of the clamping cone in the same way—by rotating the tensioning screw in the opposite direction or by moving the tensioning screw in the opposite direction in the direction of the longitudinal axis of the compressing mechanism—as a consequence of which, the at least one clamping jaw is moved outward perpendicular to the radial direction away from the longitudinal axis of the clamping area of the compressing mechanism.
Alternatively to the above-described realizations of the clamping area, it is equally conceivable to configure the clamping area of the compressing mechanism so as to be for example rotatable about the longitudinal axis of the compressing mechanism relative the at least one clamping jaw and interact with the at least one clamping jaw such that the at least one clamping jaw moves in the radial direction upon a rotation of the clamping area relative the at least one clamping jaw.
In a preferred configuration of the latter embodiment of the clamping area, it is conceivable to configure the clamping area as a hollow cylinder exhibiting a substantially uniform external diameter, whereby the wall thickness to the clamping area configured as a hollow cylinder, however, varies along its periphery so that the internal diameter of the clamping area likewise varies. Conceivable here, for example, is for the inner lateral surface of the clamping area configured as a hollow cylinder to be of sinuous or sawtooth-like form in the unfolded state. In the case of a clamping area designed as a hollow cylinder and having a wall thickness which varies along its periphery, the at least one clamping jaw of the compressing mechanism is to abut against the inner lateral surface of the clamping area designed as a hollow cylinder such that when the clamping area is rotated relative the at least one clamping jaw, the at least one clamping jaw is moved—in dependence on the wall thickness of the hollow cylinder in the contact area with the at least one clamping jaw—in the radial direction.
Alternatively to the above-described realizations of the clamping area, it is equally conceivable for the clamping area to be movable in the direction of the longitudinal axis of the compressing mechanism relative the at least one clamping jaw and to interact with the at least one clamping jaw such that upon the clamping area moving relative the at least one clamping jaw, the at least one clamping jaw is moved in the radial direction.
In one configuration of the latter embodiment of the clamping area, it is preferable for the clamping area to be configured as a hollow cylinder, the wall thickness of which varies along its periphery, whereby the at least one clamping jaw abuts the inner lateral surface of the clamping area configured as a hollow cylinder such that upon the clamping area moving relative the at least one clamping jaw, the at least one clamping jaw is moved—in dependence on the wall thickness of the hollow cylinder in the contact area with the at least one clamping jaw—in the radial direction.
Particularly conceivable with the latter embodiments of the clamping area is for the clamping area to be movable in the direction of the longitudinal axis of the compressing mechanism relative the funnel-shaped area.
In the cited possible configurations of the clamping area of the compressing mechanism, the degree of compressive force exerted radially by the at least one clamping jaw on the stent accommodated in the compressing mechanism, in the clamping area of the compressing mechanism respectively, can be adjusted by appropriately selecting the configuration of the inner lateral surface of the clamping area configured as a hollow cylinder. Specifically, the greater degree to which the wall thickness along the periphery of the clamping area configured as a hollow cylinder increases, the larger the compressive force acting radially on the outer surface of the stent accommodated in the clamping area of the compressing mechanism by the at least one clamping jaw.
It is in principle preferred for the compressing mechanism to exhibit a plurality of actuatable clamping jaws so as to enable the most even distribution possible of the compressive force exerted on the outer surface of the stent to be compressed accommodated in the clamping area. If a hollow cylinder is used as the clamping area, its wall thickness varying along its periphery, wherein the respective clamping jaws abut the inner lateral surface of the clamping area configured as a hollow cylinder such that upon rotating the clamping area relative to the clamping jaws or upon moving of the clamping area in the direction of the longitudinal axis of the compressing mechanism relative to the clamping jaws, the clamping jaws are moved radially—in dependence on the wall thickness of the hollow cylinder in the contact area with the respective clamping jaws—it is preferred for the inner lateral surface of the clamping area configured as a hollow cylinder to be configured such that the clamping jaws move uniformly in the radial direction upon the rotating of the clamping area relative to the clamping jaws or upon the moving of the clamping area in the direction of the longitudinal axis of the compressing mechanism relative to the clamping jaws. In this way, upon the compressing of the stent in the clamping area of the compressing mechanism, this allows the achieving of the stent being radially subjected to even compressive forces from all sides in order to thus ensure an uniformly even compressing of the stent without stress peaks.
In the latter cited embodiment of the clamping area in which the clamping area is rotatable or movable relative the at least one clamping jaw about the longitudinal axis of the compressing mechanism and interacts with the at least one clamping jaw such that upon a rotation or movement of the clamping area or upon displacement in the direction of the longitudinal axis of the compressing mechanism, the at least one clamping jaw is moved in the radial direction, it is preferred for the clamping area to not only be rotatable about the longitudinal axis of the compressing mechanism relative the at least one clamping jaw or movable in the direction of the longitudinal axis of the compressing mechanism relative the at least one clamping jaw, but also relative the funnel-shaped area of the compressing mechanism. So doing simplifies the manipulating of the compressing mechanism since e.g. the user of the compressing mechanism can hold the funnel-shaped area of the compressing mechanism with his one hand while he rotates the clamping area of the compressing mechanism about the longitudinal axis of the compressing mechanism relative the funnel-shaped area or moves it in the direction of the longitudinal axis of the compressing mechanism relative the funnel-shaped area with his other hand and thus manipulates the at least one clamping jaw such that it moves in the radial direction and enables a compressing of the stent accommodated in the clamping area of the compressing mechanism.
The compressing mechanism and the gripping mechanism need not be respectively configured as separate components. The disclosure is however not limited to the previously-described device for compressing a stent to which a prosthetic heart valve is affixed as needed. Rather, another object of the present disclosure also comprises a system for loading a stent, as needed with a prosthetic heart valve affixed thereto, into a medical delivery system, in particular into the catheter tip of a medical delivery system. The system thereby comprises a device of the type as described above consisting of a compressing mechanism and a gripping mechanism. Additionally to the compressing mechanism, the system further comprises a supplementary compressing mechanism.
As will be described below in detail making reference to the accompanying figures, the compressing mechanism serves to compress in particular the distal end section of the stent to be loaded into the catheter tip of a medical delivery system and to load it into a first sleeve-shaped element (receiving area) of the catheter tip. The supplementary compressing mechanism is then employed in order to compress in particular the proximal end section of the stent and load said compressed proximal end section of the stent into a further sleeve-shaped element (receiving area) of the catheter tip.
Structurally and functionally, the supplementary compressing mechanism can be con-figured similar to the compressing mechanism employed in the device to compress a stent. Since the supplementary compressing mechanism does not come into use until the distal end section of the stent has already been compressed and loaded into the first sleeve-shaped element of the catheter tip, it is thus in principle conceivable to make use of the compressing mechanism which was already used to compress the distal end section of the stent as the supplementary compressing mechanism. It is however also conceivable for the system to be provided with two compressing mechanisms for loading a stent into a medical delivery system, whereby one of the two compressing mechanisms is then used as the supplementary compressing mechanism.
Thus, both the above-described device, with which a stent, as needed with a prosthetic heart valve affixed thereto, can be readily compressed, as well as the above-described system thereto, provides for loading a stent, as needed with a prosthetic heart valve affixed thereto, into a medical delivery system, in particular into a catheter tip of a medical delivery system.
The present disclosure further relates to a method for loading a stent, as needed with a prosthetic heart valve affixed thereto, into a medical delivery system, in particular into the tip of a catheter of a medical delivery system, whereby the above-described device is used to compress the stent.
In the method for loading a stent into e.g. the catheter tip of a medical delivery system, the gripping mechanism of the device is first connected with the compressing mechanism such that the gripping mechanism is at least partly accommodated within the compressing mechanism. It is hereby preferred for at least one guiding element to be designated for the gripping mechanism which is configured to be complementary to at least one guiding element designated for the compressing mechanism and which engages with the guiding element of the compressing mechanism when the gripping mechanism connects to the compressing mechanism.
After the gripping mechanism connects to the compressing mechanism, the stent to be accommodated for example in the catheter tip of the medical delivery system is grasped, and is done so in that by actuating the actuating element of the gripping mechanism, the claw of the gripping mechanism is accordingly manipulated so that a releasable connection is formed between a distal end section of the stent and the claw of the gripping mechanism. As already detailed in conjunction with the device for compressing a stent, it is preferred for a precompressing of at least the distal end section of the stent to occur upon the grasping of the stent. This can be realized when following the forming of a releasable connection between the distal end section of the stent and the claw of the gripping mechanism, the claw is moved toward the actuating element relative the preferably provided guide sleeve by the actuating of the actuating element.
A further precompressing of the stent occurs in a subsequent method step in which the gripping mechanism with the claw, to which the distal end section of the stent is releasably affixed, is moved in the longitudinal direction relative the compressing mechanism such that the stent is at least partly accommodated within the compressing mechanism. By the gripping mechanism moving in the longitudinal direction of the compressing mechanism relative said compressing mechanism, the stent releasably connected to the claw of the gripping mechanism is thus introduced into the interior of the compressing mechanism. It is hereby advantageous for the compressing mechanism to exhibit the previously-described funnel-shaped area at the insertion end of the compressing mechanism in order to facilitate the insertion of the stent into the compressing mechanism, the clamping area of the compressing mechanism respectively.
After the stent, as needed with a prosthetic heart valve affixed thereto, has been at least partly accommodated inside the compressing mechanism, the connection between the stent and the gripping mechanism is disengaged. This ensues by a re-actuating of the actuating element of the gripping mechanism so that the claw of the gripping mechanism can be manipulated such that it moves relative to the gripping mechanism and the connection between the distal end section of the stent and the claw is disengaged.
After the gripping mechanism releases from the stent, the actual compressing of at least the distal end section of the stent occurs in the clamping area of the compressing mechanism. To this end, the at least one clamping jaw of the compressing mechanism is manipulated such that the at least one clamping jaw moves radially relative the compressing mechanism perpendicular to the direction of the longitudinal axis of the compressing mechanism. As previously described in conjunction with the device, the manipulating of the at least one clamping jaw can ensue for example by the corresponding actuating of a clamping chuck-like mechanism of the compressing mechanism which effects a movement of the at least one clamping jaw in the direction of the longitudinal axis of the compressing mechanism.
After at least the distal end section of the stent being thus so compressed in defined manner in the compressing mechanism such that the diameter of at least the distal end section of the stent exhibits a predefinable value, the compressed distal end section of the stent is introduced into a first sleeve-shaped element (receiving area) of the catheter tip of the medical delivery system.
The method for loading a stent into the catheter tip of a medical delivery system preferably provides for the compressing mechanism to introduce at least the distal end section of the stent into at least one area of the catheter tip of the medical delivery system prior to the manipulation of the at least one clamping jaw during the actual compressing. Only after the compressing mechanism with the stent accommodated therein is inserted into the tip of the catheter of the medical delivery system does the actual compressing of at least the distal end section of the stent occur by the appropriate manipulating of the at least one clamping jaw of the compression mechanism. This occurs because the diameter of the compressed distal end section of the stent is normally smaller than the external diameter of the catheter tip of the medical delivery system such that the actual compressing of the distal end section of the stent is to occur in direct proximity to the first sleeve-shaped element of the catheter tip.
In order to achieve that also the proximal end section of the stent can be accommodated in compressed manner in the catheter tip of the medical delivery system, a preferred embodiment of the method makes use of the above-noted supplementary compressing mechanism. Specifically, it is thereby provided that at least one area of the catheter tip of the medical delivery system is inserted through the supplementary compressing mechanism configured as a hollow cylindrical body such that the supplementary compressing mechanism abuts against the (not yet fully compressed) proximal end section of the stent at least partly accommodated within the compressing mechanism.
Before the supplementary compressing mechanism is used to compress the proximal end section of the stent, however, it is preferable to remove the compressing mechanism, with which the distal end section of the stent is compressed, from the catheter tip of the medical delivery system. This should occur after the compressed distal end section of the stent has been loaded into the first sleeve-shaped element of the catheter tip.
To remove the compressing mechanism, the at least one clamping jaw of the compressing mechanism is manipulated such that the at least one clamping jaw is moved radially outward relative the compressing mechanism away from the longitudinal axis of the compressing mechanism. Because the distal end section of the stent is already loaded into the first sleeve-shaped element of the catheter tip, the distal end section of the stent remains in its compressed form although the at least one clamping jaw of the compressing mechanism now no longer exerts a radially-acting compressive force on the stent.
After the at least one clamping jaw of the compressing mechanism being manipulated so as to no longer exert any radial compressive force on the outer surface of the stent, the compressing mechanism can be removed from the catheter tip of the medical delivery system.
The supplementary compressing mechanism can thereafter be used to compress the not yet fully compressed proximal end section of the stent such that the proximal end section of the stent can be loaded into a further sleeve-shaped element of the catheter tip.
To this end, the supplementary compressing mechanism is moved toward the proximal end section of the stent such that at least the proximal end section of the stent is at least partly received within the supplementary compressing mechanism configured as a hollow cylindrical body. In this position, the supplementary compressing mechanism can effect a compressing of at least the proximal end section of the stent.
In detail, at least the proximal end section of the stent is compressed in that the at least one clamping jaw of the supplementary compressing mechanism is manipulated such that the at least one clamping jaw is radially moved relative the supplementary compressing mechanism perpendicular to the direction of the longitudinal axis of said supplementary compressing mechanism. It is readily apparent that the degree of compression of the proximal end section of the stent is selectable at will, and this is done by correspondingly selecting the extent of manipulation for the at least one clamping jaw of the supplementary compressing mechanism. The same also applies figuratively to the compressing of the distal end section of the stent.
After the supplementary compressing mechanism compressing the proximal end section of the stent, the compressed proximal end section of the stent is introduced into at least one second sleeve-shaped element (receiving area) of the catheter tip of the medical delivery system.
The supplementary compressing mechanism can thereafter also be removed from the catheter tip of the medical delivery system. This ensues by correspondingly manipulating the at least one clamping jaw of the supplementary compressing mechanism such that the at least one clamping jaw is radially moved outward relative the supplementary compressing mechanism perpendicular to the radial direction of the longitudinal axis of said supplementary compressing mechanism.
The following will make reference to the accompanying drawings in describing examples of the disclosed solution.
Shown are:
a a perspective view of the clamping mechanism used in the clamping area of the compressing mechanism of the exemplary embodiment of the device for compressing a stent;
b a perspective view from below into the funnel-shaped area of the compressing mechanism shown in
a-f perspective views of the exemplary embodiment of the device illustrating the functioning during the compression of a stent;
a-c perspective views of the exemplary embodiment of the system illustrating the loading of a stent into the catheter tip of a medical delivery system;
Reference will be made in the following to the accompanying drawings in describing an exemplary embodiment of the device 1 for compressing a stent 100.
The device 1 substantially comprises a compressing mechanism 10 in the form of a hollow cylindrical body, within which a stent, not shown in
The exemplary embodiment of device 1 depicted in
As will subsequently be described in detail in the following, the compressing mechanism 10 serves the device 1 with respect to the exerting of a compressive force acting in the radial direction (relative the longitudinal direction of said compressing mechanism 10) on a stent accommodated in the compressing mechanism 10 in defined manner so as to reduce the cross-section of the stent to a predefinable value. In doing so, it is first required for the stent to be compressed to be at least partly inserted into the compressing mechanism 10 configured as a hollow cylinder. This task is assumed by the gripping mechanism 20 of the device 1 which—as will be described below in greater detail—is designed so as to create a releasable connection with the stent to be compressed. In particular, the gripping mechanism 20 serves to create a releasable connection with the distal end section of the stent to be compressed and thereafter introduce the stent into the compressing mechanism 10 configured as a hollow cylinder.
To this end, the gripping mechanism 20 is displaceably receivable within the compressing mechanism 10 configured as a hollow cylinder in the longitudinal direction relative said compressing mechanism 10. The gripping mechanism 20 further comprises an actuating element 21 provided with a claw 22 for grasping the stent to be compressed.
In the exemplary embodiment depicted in the drawings, the actuating element 21 of the gripping mechanism 20 exhibits a manually-actuatable pushbutton 26 accommodated in a retaining section 25 and displaceable in the longitudinal direction of the gripping mechanism 20 relative a guide sleeve 23.
To be seen in conjunction hereto from the representation provided in
By actuating element 21 being pressed by the pushbutton 26—as shown in FIG. 2—the claw 22 of gripping mechanism 20 is thus at least partly moved out of the guide sleeve 23. The distance by which the claw 22 is moved out of the guide sleeve 23 depends on the actuated travel of the pushbutton 26.
In the exemplary embodiment of device 1, the claw 22 exhibits three gripper arms 27.1, 27.2, 27.3, whereby each gripper arm 27.1, 27.2, 27.3 comprises respective fastening means 28.1, 28.2 at its first end section. These fastening means 28.1, 28.2 serve to form a releasable connection with a stent to be compressed, as will be subsequently described in detail referencing the representations provided in
The fastening means 28.1, 28.2 respectively provided on the first end sections of the gripper arms 27.1, 27.2, 27.3 are designed in complementary fashion to a retaining section formed on the stent to be compressed so that the fastening means 28.1, 28.2 are designed to releasably engage with a retaining section of the stent to be compressed. In detail, and as can particularly be seen from the representations provided in
The gripping mechanism 20 used in the exemplary embodiment of the device 1 will be described in greater detail in the following referencing the representations provided in
As already described in conjunction with the
It is preferred for the maximum gripping area of claw 22, gripper arms 27.1, 27.2, 27.3 respectively, to be such so as to be able to grasp stents up to an external diameter of 30.0 mm. However, it is of course also possible to dimension the gripping area of claw 22 for stents having larger external diameters.
As will be described in greater detail referencing the representations provided in
It is of course also conceivable to dispense with the guide shaft 29 and directly connect the second end sections of the respective gripper arms 27.1, 27.2, 27.3 to the actuating element 21 of the gripping mechanism 20, respectively to the pushbutton 26 of said actuating element 21. However, the guide shaft 29 enables the claw 22 to be moved with as little resistance as possible relative the guide sleeve 23 upon actuating element 21 being actuated.
In order to prevent the possible canting or wedging of the guide shaft 29 in its movement relative to the guide sleeve 23 upon the actuating element 21 being actuated, the exemplary embodiment of device 1 provides guiding means 30 to guide the guide shaft 29 within the guide sleeve 23 when the guide shaft 29—as depicted for example in FIGS. 3 and 4—is accommodated within the guide sleeve such that the guide shaft 29 together with the gripper arms 27.1, 27.2, 27.3 connected to said guide shaft 29 can be displaced relative to guide sleeve 23.
To be noted from the
As can be noted from the perspective representation according to
Providing the spring mechanism in retaining section 25 of actuating element 21 as realized by means of the spring 31 thus ensures that the gripping mechanism 20 will be held in the initial state as shown in
Selecting the appropriate spring constant or stiffness to spring 31 of the spring mechanism enables spring 31 to set the pretensioning exerted on pushbutton 26 of actuating element 21. To be factored in hereby is that the pretensioning is to be selected such that without impacting any compressive force exerted externally on the pushbutton 26; i.e. in the initial state of the gripping mechanism 20, the claw 22—with the exception of the fastening means 28.1, 28.2 provided at the first end section of gripper arms 27.1, 27.2, 27.3—is completely accommodated within guide sleeve 23. This should preferably also be the case when the claw 22 grasps a stent to be compressed via the fastening means 28.1, 28.2 of gripper arms 27.1, 27.2, 27.3.
As already indicated with reference to the
As can be seen for example in the representation of
It can in particular be noted from the
The compressing mechanism 10 used in the exemplary embodiment of the device 1 will be described in the following making reference to the
It is hereby noted that only for the sake of clarity in the drawings, the stent 100 is depicted schematically as a cylindrical body without any further rendering of the stent's structural details. The device 1 is suited for cylindrical stents with which the gripping mechanism 20 can create a releasable connection in order to introduce the stent 100 into the compressing mechanism 10. In particular, the device is suited to compress a stent 100 which comprises retaining elements on its distal end section 101 with which the gripping mechanism 20 can form a releasable connection.
The device 1 is suited to compress an expandable, and in particular self-expandable stent 100. The stent 100 assumes—while it is accommodated in the catheter tip of the medical delivery system—a first predefinable shape. However, outside of the catheter tip, in the implanted state respectively, the stent 100 is in a second predefinable shape. The first shape of the stent 100 thereby corresponds to the folded state while in the expanded state, the stent 100 is in its second shape.
For example, the device 1 is suitable for compressing a stent 100 as described for example in European patent application No. 07 110 318 or European patent application No. 08 151 963. A preferred realization of device 1 accordingly designed to compress a stent 100 thus comprises the following:
The use of device 1 is however in no way limited to this type of stent.
As can be seen from the
As will be described in greater detail below referencing the
In detail, the exemplary embodiment of the device 1 provides for the clamping area 14 to be rotatable about the longitudinal axis of the compressing mechanism 10 relative the funnel-shaped area 13. On the other hand, the clamping jaws 11.1-11.6 provided in clamping area 14 are connected to the funnel-shaped area 13, as can be seen in the
It can be noted from the top plan view of compressing mechanism 10 shown in
The functioning of the compressing mechanism 10 used in the exemplary embodiment of device 1 will be described in greater detail in the following referencing the representations provided in
In detail, it can be noted from the
The individual clamping jaws 11.1-11.6 are preferably configured such that they exhibit a relatively large contact surface 15 over which the radial compressive force from clamping jaws 11.1-11.6 is exerted on the outer surface of the stent 100 in the compressing of stent 100.
If the clamping area 14—starting from the state as shown in FIG. 6—is now rotated relative the funnel-shaped area 13 and thus relative the clamping jaws 11.1-11.6 in the direction of the arrow, the individual clamping jaws 11.1-11.6 will be radially pressed in the direction of the longitudinal axis of the compressing mechanism 10. This is to be attributed to the clamping jaws 11.1-11.6 being guided along the inner lateral surfaces of clamping area 14 by the rotating of clamping area 14 relative clamping jaws 11.1-11.6.
In detail, the compressing mechanism 100 employed in the exemplary embodiment of the device 1 provides a respective grooved guide 16.1-16.6 for each clamping jaw 11.1-11.6, whereby the respective transfer functions of grooved guides 16.1-16.6 are determined by the course taken by the respective guiding surfaces 17.1-17.6 provided for clamping jaws 11.1-11.6. The respective clamping jaws 11.1 to 11.6 are forcibly driven along guiding surfaces 17.1-17.6 of the respective grooved guides 16.1-16.6 upon clamping area 14 being rotated relative to the clamping jaws 11.1-11.6.
The respective grooved guides 16.1-16.6 are thereby selected such that a transfer function is realized upon clamping area 14 being rotated relative the clamping jaws 11.1-11.6 which effects a movement of clamping jaws 11.1-11.6 in the radial direction.
The compressing mechanism 10 depicted in the drawings makes use of a total of six clamping jaws 11.1-11.6 to transfer the compressive force acting radially on the lateral surface of stent 100 as evenly as possible during the compressing of stent 100.
The contact surfaces 15.1-15.6 of clamping jaws 11.1-11.6 are moreover designed to encompass large areas so as to avoid stress peaks during the transfer of the radially-acting compressive force so that unnecessary stressing and possibly damaging of the stent 100 can be prevented during its compression.
The present disclosure is not limited to the clamping mechanism as described above with reference to the representations of
A preferred use of the above-described exemplary embodiment of device 1 will be described in the following referencing the representations shown in
a depicts the device 1 in its initial state as described above referencing the representations shown in
c shows how a stent 100 to be compressed can be grasped by the claw 22 extending partly from the guide sleeve 23. It is hereby to be assumed that the fastening means 28.1, 28.2 provided at the end section of gripper arms 27.1, 27.2, 27.3 are releasably connected to a retaining section provided at the distal end section 101 of the stent 100 to be compressed. It is hereby conceivable, for example, for the fastening means 28.1, 28.2 of gripper arms 27.1, 27.2, 27.3 to form a releasable engagement with corresponding retaining elements of the stent 100 to be compressed.
After the claw 22 is connected to the distal end section 101 of stent 100 via the fastening means 28.1, 28.2 of gripper arms 27.1, 27.2, 27.3, the pushbutton 26 of actuating element 21 is released—as shown in
Subsequently, as shown in
After the stent 100 is received in the compressing mechanism 10, the connection between the claw 22 of gripping mechanism 20 and the distal end section 101 of the stent 100 is again disengaged—as can be seen in the representation according to
The stent 100 thus inserted into the compressing mechanism 10 can now be compressed to the desired diameter, and in fact done so by the clamping area 14 being rotated relative to the funnel-shaped area 13 such that the clamping jaws 11.1-11.6 exert a radial compressive force on at least one area of the lateral surface of the stent 100 accommodated in the compressing mechanism 10. How the stent 100 can specifically be compressed within compressing mechanism 10 has already described with reference to
The functioning of an exemplary embodiment of the system for loading a stent 100 into the catheter tip 105 of a medical delivery system will be described in the following referencing the
The embodiment of the system for loading a stent 100 into the catheter tip 105 of a medical delivery system as depicted in
To load the stent 100 into the catheter tip 105 of the medical delivery system, the gripping mechanism 20 first inserts the stent 100 into the compressing mechanism 10, as has been described in detail referencing
Prior to the compressing mechanism 10 effecting the compressing of the stent 100, the catheter tip 105 of the medical delivery system is first introduced through the compressing mechanism 10 and then the precompressed stent 100 in the compressing mechanism 10. Not until that point is the stent 100 accommodated in the compressing mechanism 10 actually compressed by manipulating the clamping jaws 11.1-11.6, as described above referencing
As depicted in
After the distal end section 101 of stent 100 has been compressed to its final diameter by means of the compressing mechanism 10, the distal end section 101 of stent 100—as shown in
For example, it is conceivable for the catheter tip 105—as will be described below referencing the depictions provided in FIGS. 12 and 13—to comprise a stent holder 150 for releasably fixing the distal end section 101 of the stent 100. The distal end section 101 of stent 100 compressed to its final diameter can then be introduced into stent holder 150 (cf.
To releasably fix the distal end section 101 of stent 100 to the catheter tip 105, it is for example further conceivable to make use of a first sleeve-shaped element 106 (cf.
After the compressed distal end section 101 of stent 100 is fixed to the catheter tip 105 by means of the compressing mechanism 10, the compressing mechanism 10 is—as shown in
In order to also have the proximal end section 102 of the stent 100 be compressed and be accommodated in the catheter tip 105 of the medical delivery system, the system as depicted in
In order to be able to load a stent 100 into the catheter tip 105 of a medical delivery system designed for a transapical approach, the catheter tip 105 of the medical delivery system first needs to be guided through the supplementary compressing mechanism 10′ and thereafter through the compressing mechanism 10, within which the already precompressed stent 100 is accommodated, as shown in
After the compressing mechanism 10 is removed from the catheter tip 105 of the medical delivery system—as shown in
The examples of the catheter tips 105-1 and 105-2 depicted in
After the compressed proximal end section 102 of stent 100 is loaded for example into the second sleeve-shaped element 107 of the catheter tip 105, the supplementary compressing mechanism 10′ is removed from the catheter tip 105 by manipulating the clamping jaws 11.1-11.6 of the supplementary compressing mechanism 10′ such that the clamping jaws 11.1-11.6 move radially outward perpendicular to the longitudinal axis of the supplementary compressing mechanism 10′.
An exemplary embodiment of a catheter tip 105-1 of a medical delivery system for transapically introducing an expanded stent into the body of a patient will be described below referencing
The catheter tip 105-1 depicted in
The medical delivery system enables an expandable heart valve stent to be implanted transapically in a patient's body; i.e. advanced from the apex of the heart. To this end, the delivery system comprises a catheter system (not shown in
The catheter tip 105-1 shown in
In detail, the catheter tip 105-1 of the medical delivery system designed for transapical approach comprises a stent holder 150 by means of which the distal end section 101 of a stent 100 to be implanted into the body of the patient can be releasably fixed to the catheter tip 105-1. The catheter tip 105-1 further comprises receiving means for receiving at least the proximal end section 102 of the stent 100. Specifically, the receiving means for the catheter tip 105-1 exemplarly depicted in
As
In the catheter tip 105-1 of the delivery system designed for a transapical approach, the second receiving area 121 of catheter tip 105-1 is configured as a stent funnel with its opening pointing toward the proximal end tip 125 of catheter tip 105-1. The proximal end section 102 of a stent 100 to be implanted (not shown in
For example, it is conceivable for the proximal end section 102 of stent 100 to comprise retaining holders to which a prosthetic heart valve is affixed as needed. In such a case, the retaining holders of stent 100, and the prosthetic heart valve affixed as needed to the retaining holders, are accommodated within the second receiving area 121 of catheter tip 105-1 configured as a stent funnel.
In the closed state of catheter tip 105-1 (cf.
In the catheter tip 105-1 of a medical delivery system designed for a transapical approach as depicted in
As indicated above, it is preferred for the first receiving area 111 of the catheter tip 105-1 of the medical delivery system designed for a transapical approach to be configured as a stent sheath, for example in the form of an elongated tube. The second receiving area 121 is preferably configured as a stent funnel, likewise for example in the form of an elongated tube. The inner diameter of the tubular or sleeve-shaped first receiving area 111 should thereby be selected to be larger than the outer diameter of the likewise tubular or sleeve-shaped second receiving area 121 such that the second receiving area 121 can be telescopically received inside the first receiving area 111.
The stent holder 150 of the catheter tip 105-1 for a medical delivery system designed for a transapical approach as depicted in
In
The procedure for loading a heart valve stent 100 into the example of the catheter tip 105-1 as depicted in
With the catheter tip 105-1 for a medical delivery system designed for a transapical approach shown as an example in
On the other hand, the first receiving area 111 of the catheter tip 105-1 is also movable in the longitudinal direction of the catheter tip 105-1 relative the stent holder 150 by means of appropriately manipulating a force transfer means. With the catheter tip 105-1 shown for example in
As indicated above, it is provided in the case of the catheter tip 105-1 for a medical delivery system designed for a transapical approach for the stent holder 150 of the catheter tip 105-1 to preferably be fixedly connected to a handle, a body of the handle respectively, so as to in particular freeze the freedom of rotational motion about the longitudinal axis of the medical delivery system respective the stent holder 150 as well as the freedom of motion in the direction of the longitudinal axis of the medical delivery system. Accordingly, the stent holder 150 is restricted from moving at least in the longitudinal direction of the medical delivery system relative the body of the handle. Rotational motion of the stent holder 150 about the longitudinal axis relative the handle is likewise eliminated.
It is to be emphasized that the system for loading a stent 100, as needed with a prosthetic heart valve 100 affixed thereto, into the tip of a catheter of a medical delivery system as disclosed above based on the example referencing
The following, referencing
The catheter tip 105-2 depicted in
The embodiment of the medical delivery system suited for a transarterial or transfemoral approach differs from the delivery system designed for transapical approach as described above referencing the
With regard to the design of the catheter tip 105-2 allowing the transarterial or transfemoral approach for the stent accommodated in the catheter tip 105-2 to the site of implantation, it can be seen from
Furthermore, the catheter tip 105-2 of the delivery system designed for a transarterial/transfemoral approach comprises receiving means to receive a heart valve stent with the prosthetic heart valve affixed thereto as needed. Specifically, the receiving means of the catheter tip 105-2 consists of a first receiving area 111 to receive the distal end section 101 of a stent 100, in particular the positioning holder of a stent, and a second receiving area 121 to receive the proximal end section 102 of the stent 100, in particular the retaining holder of the stent with the prosthetic heart valve affixed thereto as needed.
As distinguished from the catheter tip 105-1 of the medical delivery system designed for a transapical approach as described with reference to
In the catheter tip 105-2 of the medical delivery system as depicted in
Upon the actuating of the associated actuating means, the second receiving area 121 (stent funnel) is movable in the longitudinal direction of the catheter tip 105-2 relative the stent holder 150 in the proximal direction; i.e. away from the (not shown) handle, while the first receiving area 111 of catheter tip 105-2 is movable, upon the actuating of the correspondingly associated actuating means of the handle, in the longitudinal direction of the catheter tip 105-2 relative stent holder 150 in the distal direction; i.e. toward the handle not shown in
The manipulations of the respective receiving areas 111, 121 of the catheter tip 105-2 of the delivery system designed for a transarterial/transfemoral approach effected by the actuating of the respective actuating means enables a sequential release of a stent 100 accommodated in the catheter tip 105-2, preferably at the site of implantation in the patient's heart.
The procedure for loading a heart valve stent 100 into the catheter tip 105-2 depicted as an example in
In order to be able to load a stent 100 into the catheter tip 105-2 of a medical delivery system designed for a transfemoral/transarterial approach, however, it is necessary to insert the catheter tip 105 of the medical delivery system through the compressing mechanism 10, within which the already precompressed stent 100 is accommodated. The distal end section 101 of the stent 100 can then be further compressed and brought into engagement with the stent holder 150 of the catheter tip 105-2. The compressing mechanism 10 can thereafter be removed from the catheter tip 105-2 of the medical delivery system. The supplementary compressing mechanism 10′ is then employed, or the previously used compressing mechanism 10 also previously removed from the catheter tip 105-2 can also be re-employed, in order to compress the proximal end section 102 of the stent 100 accordingly. As is also the case in the loading procedure for a catheter tip designed for a transapical approach (cf.
In summary, it remains to be noted that the above disclosure transforms a stent, as needed with a prosthetic heart valve affixed thereto, from its expanded state into a compressed state in particularly smooth manner. The above disclosure is not only suited to compressing stents, but also grasping a stent in the catheter tip of a transapical or transfemoral medical delivery system. The degree of compression is adjustable at will.
The disclosed solution is not limited to the embodiments described with reference to the accompanying drawings. Also just as conceivable in fact are combinations of the individual features as specifically described.
A device (1) for compressing a stent (100) or—if required—a stent (100) with a prosthetic heart valve affixed thereto, wherein the device (1) comprises the following:
Wherein the gripping mechanism (20) comprises a guide sleeve (23) in which the claw (22) can be at least partly accommodated.
Wherein the diameter exhibited by the stent (100) after its compression effected by the device (1) is definable by an internal diameter of the guide sleeve (23).
Wherein the claw (22) is movable relative the guide sleeve (23) upon actuating of the actuating element (21).
Wherein the guide sleeve (23) comprises at least one guiding element (24) configured complementary to the at least one guiding element (12) allocated to the compressing mechanism (10).
Wherein the at least one guiding element (24) allocated to the guide sleeve (23) is configured as a guide rail.
Wherein the gripping mechanism (20) comprises a retaining section (25) arranged coaxially to the guide sleeve (23) and connected to said guide sleeve (23).
Wherein the actuating element (21) comprises a preferably manually-actuatable pushbutton (26) accommodated in the retaining section (25) and movable in the longitudinal direction of the gripping mechanism (20) relative the guide sleeve (23).
Wherein the claw (22) comprises at least one and preferably three gripper arms (27.1, 27.2, 27.3) wherein fastening means (28.1, 28.2) are preferably provided on the first end section of the at least one gripper arm (27.1, 27.2, 27.3) to create a releasable connection with a stent (100) to be compressed, in particular with a distal end section (101) of the stent (100) to be compressed.
Wherein the fastening means (28.1, 28.2) provided on the at least one gripper arm (27.1, 27.2, 27.3) are configured to be complementary to a retaining section or complementary to a retaining element of the stent (100) to be compressed, in particular such that the fastening means (28.1, 28.2) are designed to form a releasable engagement with the retaining section of the stent (100) to be compressed.
Wherein the fastening means (28.1, 28.2) provided on the at least one gripper arm (27.1, 27.2, 27.3) comprise at least one projecting element (28.1) which can be brought into releasable engagement with a retaining grommet of a stent (100) to be compressed designed to be correspondingly complementary thereto.
Wherein the fastening means (28.1, 28.2) provided on the at least one gripper arm (27.1, 27.2, 27.3) exhibit at least one recess (28.2) configured in the first end section of said gripper arm (27.1, 27.2, 27.3), in particular in the form of a preferably oblong grommet, which can be brought into releasable engagement with a projecting retaining element of a stent (100) to be compressed designed complementary thereto.
Wherein the at least one gripper arm (27.1, 27.2, 27.3) comprises the fastening means (28.1, 28.2) at its first end section and is connected to the fastening element (21) of the gripping mechanism (20) by its opposite second end section.
Wherein the claw (22) comprises a guide shaft (20), wherein the first end section (29a) of the guide shaft (29) is connected to the second end section of the at least one gripper arm (27.1, 27.2, 27.3) and the second end section (29b) of the guide shaft (29) is connected to the actuating element (21) of the gripping mechanism (20).
Wherein the guide shaft (29) is accommodated within the guide sleeve (23) such that said guide shaft (29) is displaceable relative the guide sleeve (23) together with the at least one gripper arm (27.1, 27.2, 27.3) connected thereto.
Wherein guide means (30) are provided to guide the guide shaft (29) within the guide sleeve (23).
Wherein the at least one gripper arm (27.1, 27.2, 27.3) is connected to the guide shaft (29) via its second end section such that the at least one gripper arm (27.1, 27.2, 27.3) protrudes from the guide shaft (29)—relative to the longitudinal direction of said guide shaft (29)—at an angle.
Wherein the at least one gripper arm (27.1, 27.2, 27.3) and/or the connecting area (33) between the second end section of the at least one gripper arm (27.1, 27.2, 27.3) and the first end section (29a) of the guide shaft (29) is/are configured so as to be elastically deformable such that upon a displacement of the guide shaft (20) relative the guide sleeve (23), the at least one gripper arm (27.1, 27.2, 27.3) connected to the guide shaft (29) can be at least partly accommodated in the guide sleeve (23) by simultaneous radial deformation.
Wherein gripping mechanism (20) comprises a spring mechanism which interacts with the claw (22) such that the claw (22) can be spring-locked.
Wherein the spring mechanism comprises a spring (31), in particular a helical compression spring, arranged in the retaining section (25) of the actuating element (21) such that it pretensions the pushbutton (26) of the actuating element (21) against the guide sleeve (23).
Wherein the pretensioning exerted by the spring (31) on the pushbutton (26) of the actuating element (21) is selected such that without on the one hand impacting the compressive force exerted externally on the pushbutton (26), the claw (22)—with the exception of the fastening means (28.1, 28.2) provided at the first end section of the at least one gripper arm (27.1, 27.2, 27.3)—is accommodated completely within the guide sleeve (23).
Wherein the stroke of the spring (31) is shorter than the length of the at least one gripper arm (27.1, 27.2, 27.3).
Wherein the compressing mechanism (10) comprises a funnel-shaped area (13) at least at one end, and wherein the compressing mechanism (10) further comprises a clamping area (14) aligned coaxially to the funnel-shaped area (13) and connected to said funnel-shaped area (13), and in which the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) is accommodated.
Wherein the compressing mechanism (10) comprises a tensioning screw accommodated in the clamping area (14) which is rotatable about the longitudinal axis of the compressing mechanism (10) relative the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) and which interacts with the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) such that upon a rotation of the tensioning screw, the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) is displaced in the longitudinal direction of the compressing mechanism (10) relative to a clamping cone accommodated in the clamping area (14).
Wherein the compressing mechanism (10) comprises a tensioning screw accommodated in the clamping area (14) which is movable along the longitudinal axis of the compressing mechanism (10) relative the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6), and which interacts with the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) such that upon a translational displacement of the tensioning screw, the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) is displaced in the longitudinal direction of the compressing mechanism (10) relative to a clamping cone accommodated in the clamping area (14).
Wherein the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) interacts with the clamping cone such that upon a movement of the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) into the clamping cone, the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) is moved in the radial direction.
Wherein the clamping area (14) is rotatable about the longitudinal axis of the compressing mechanism (10) relative the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) and interacts with the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) such that the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) moves in the radial direction upon a rotation of the clamping area (14).
Wherein the clamping area (14) is configured as a hollow cylinder exhibiting varying wall thicknesses along its periphery, wherein the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) abuts the inner lateral surface of the clamping area (14) configured as a hollow cylinder such that when the clamping area (14) is rotated relative the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6), the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) is moved—in dependence on the wall thickness of the hollow cylinder in the contact area with the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6)—in the radial direction.
Wherein the clamping area (14) is rotatable about the longitudinal axis of the compressing mechanism (10) relative the funnel-shaped area (13).
Wherein the clamping area (14) is movable along the longitudinal axis of the compressing mechanism (10) relative the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) and interacts with the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) such that the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) moves in the radial direction upon a translational displacement of the clamping area (14).
Wherein the clamping area (14) is configured as a hollow cylinder exhibiting varying wall thicknesses along its periphery, wherein the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) abuts the inner lateral surface of the clamping area (14) configured as a hollow cylinder such that when the clamping area (14) is shifted along the longitudinal axis of the compressing mechanism (10) relative the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6), the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) is moved—in dependence on the wall thickness of the hollow cylinder in the contact area with the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6)—in the radial direction.
Wherein the clamping area (14) is movable along the longitudinal axis of the compressing mechanism (10) relative the funnel-shaped area (13).
A system for loading a stent (100) or—if required—a stent (100) with a prosthetic heart valve affixed thereto into a medical delivery system, in particular a catheter tip (105) of a medical delivery system, wherein the system comprises a device (1) in accordance with any one of the preceding claims and a supplementary compressing mechanism (10′) for compressing the proximal end section (102) of the stent (100), wherein the supplementary compressing mechanism (10′) is configured analogously to the compressing mechanism (10) of the device (1) in accordance with any one of the preceding claims.
The use of a device according to any one of claims 1 to 32 or a system according to claim 33 for loading a stent (100) or—if required—a stent (100) with a prosthetic heart valve affixed thereto into a medical delivery system, in particular into a catheter tip (105) of a medical delivery system.
A method for loading a stent (100) or—if required—a stent (100) with a prosthetic heart valve affixed thereto into a medical delivery system, in particular into a catheter tip (105) of a medical delivery system, wherein the method comprises the following method steps:
Wherein prior to the manipulation of the at least one clamping jaw (11.1, 11.2, 11.3, 11.4, 11.5, 11.6) in method step vi), at least one area of the catheter tip (105) of the medical delivery system is guided through the compressing mechanism (10) configured as a hollow cylindrical body.
Wherein at least one area of the catheter tip (105) of the medical delivery system is guided through a supplementary compressing mechanism (10′) configured as a hollow cylindrical body such that the supplementary compressing mechanism (10′) abuts the proximal end section (102) of the stent (100) at least partly accommodated within the compressing mechanism (10).
Wherein the method comprises the following method steps subsequent the introduction of the compressed distal end section (101) of stent (100) in a first sleeve-shaped element (106) of the catheter tip (105) of the medical delivery system in method step vii):
This application claims priority to U.S. Provisional Patent Application No. 61/178,701, filed May 15, 2009, the entire contents of which are hereby incorporated herein by reference.
Number | Date | Country | |
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61178701 | May 2009 | US |