Rolling film catheter

Abstract

The catheter includes a rolling membrane and at least one locking device configured to lock movement of the rolling membrane based at least in part on a fluid state of the catheter.

Description

Technical Field

[0001] The present invention relates to a catheter including a rolling membrane and various devices for facilitating the practical use of such a catheter. Further, a corresponding system including such a catheter and at least one fluid unit is provided. The present invention further relates to the use of a tubular element including a friction reducing element as a rolling membrane. The present invention also relates to corresponding computer programs and methods. Background Art

[0002] Medical treatment of a stenosis via percutaneous coronary intervention (PCI) may involve inserting a catheter into a blood vessel at the location of the stenosis. A rolling membrane catheter may allow the catheter to be inserted into a stenotic cavity by flipping the rolling membrane during the unrolling process. Typically, in a first step, a guide wire is introduced into the blood vessel and guided to the treatment site, such as the location of the stenosis. Then, the rolling membrane of the rolling membrane catheter can be everted, for example, by providing pressure to the interior of the rolling membrane via a fluid unit connected to the catheter via a fluid inlet and moving one end (e.g., the proximal and / or inner end) of the rolling membrane distally. This may cause the rolling membrane to flip along the blood vessel wall, for example, without substantial friction. One end of the rolling membrane may be attached to, for example, an inner shaft, which moves distally when the rolling membrane attached to the distal end of the inner shaft is everted. This causes the rolling membrane to evert in the distal direction towards and possibly past the stenosis. The inserted rolling membrane may, for example, widen the stenosis or be used as a guiding catheter for introducing other devices into the blood vessel at the location of the stenosis.

[0003] However, there are some problems that need attention when using a rolling membrane catheter. First, in a conventional rolling membrane catheter, the user may retract the rolling membrane when the rolling membrane is in an insufficiently inflated state, such that the rolling membrane is clamped. Second, if used together with a guide wire, when in the inflated state, the hydraulic pressure in the rolling membrane typically clamps the guide wire and thus couples it to its movement. Due to the eversion movement of the rolling membrane, the advancement speed of the guide wire is twice that of the leading edge of the everted rolling membrane. This requires special care to control the advancement of the guide wire in order to avoid the risk of perforating the patient's cardiovascular system. In addition, the flipping and / or retraction of the rolling membrane will be accompanied by a certain pressure applied to the rolling membrane. If the user (e.g., a health professional introducing the catheter) sets too high a pressure, the burst pressure of the rolling membrane may be exceeded, such that the rolling membrane may burst within the patient's cardiovascular system. Therefore, there is still a need to improve the rolling membrane catheter. Summary of the Invention

[0004] According to a first aspect of the present invention, a catheter including a rolling membrane can be provided. The catheter can also include at least one locking device configured to lock the rolling membrane at least partially based on the fluid state of the catheter. For example, when insufficient fluid pressure is provided to the rolling membrane, the rolling membrane can be locked, such as so that it cannot evert or retract. Then, it may be advantageous to lock the rolling membrane and prevent, for example, retraction of the rolling membrane by retracting a member attached to one end of the rolling membrane, as this may cause the rolling membrane to kink. Thus, such locking can not only prevent damage to the catheter but also reduce the risk to the patient associated with removing a damaged catheter. In some examples, the locking device can be activated in addition or alternatively if the fluid pressure provided to the rolling membrane is too high. Thus, this can avoid, for example, the membrane bursting by further retracting the rolling membrane.

[0005] In an example, the locking can prevent movement of the inner shaft of the catheter relative to the outer shaft of the catheter, where the rolling membrane can be connected to the distal regions of both the inner shaft and the outer shaft. Thus, movement of the rolling membrane, i.e., eversion and / or retraction, can be prevented.

[0006] The fluid state should be understood as the state of the fluid within any volume of the catheter as described herein. The fluid state can relate to, for example, fluid pressure and / or fluid flow rate. The fluid can be any liquid fluid, any gaseous fluid, and / or any combination thereof. The fluid state of the catheter can particularly relate to the fluid state of the membrane. For example, the locking device can be configured to lock the rolling membrane as long as the fluid pressure applied to the volume of the rolling membrane is below a predetermined threshold in order to prevent the membrane from moving when in an under-inflated state. The locking device can be configured to release the rolling membrane when the fluid pressure applied to the volume of the rolling membrane reaches the predetermined threshold.

[0007] In some examples, the catheter includes at least one locking device that can be at least partially connected to at least a portion of the outer shaft of the catheter. This can be achieved, for example, in an advantageous configuration where the locking device is an integral part of the outer shaft of the rolling membrane catheter, thereby saving both material and the space required. This can improve overall handling and safety.

[0008] In an example, one or more portions of the outer shaft may be formed by locking means, such as interlocking and / or friction locking means. To this end, members may be provided on the outer shaft that interact with members on the inner shaft to lock the movement of the rolling membrane. For example, the locking means may be further shaped in such a way that, for example, by selecting a rough and / or friction-increasing material and / or by providing members and / or portions configured to interlock or otherwise engage with each other (such as serrated portions), interlocking and / or friction locking is facilitated. This can result in a compact, material-saving catheter design, thereby reducing labor and material costs in production. The locking means may, for example, include one or more annular elements that replace a portion of the outer shaft, the annular elements being biased to engage with the inner shaft, unless the pressure provided to the lumen between the inner and outer shafts lifts them away from the inner shaft and thus unlocks the rolling membrane. However, additionally or alternatively, other elements, such as knobs integrated into the surface of the outer shaft, having, for example, a circular or any other cross-section may be employed. A number of such non-annular elements may be distributed around the circumference of the outer shaft. The catheter may include at least one locking means configured to be in a first configuration that locks the movement of the rolling membrane when insufficient fluid pressure is provided to the catheter. Additionally, the locking means may be configured to be in a second configuration that unlocks the movement of the rolling membrane when sufficient fluid pressure is provided to the catheter. In the present context, the term "lock" may be understood as preventing movement of at least one member relative to at least one other member of the catheter, and "unlock" may be understood as allowing movement of at least one member relative to at least one other member of the catheter. The member may, for example, be any device / element / building block / (sub)unit of the catheter. For example, when the locking means is connected to the outer shaft, the locking means may be in the second configuration when in a lifted position, in which, for example, there is no contact between the locking means and the inner shaft and / or a corresponding mating part connected to the inner shaft. When the locking means is in the first configuration, the locking means may also be in contact with the inner shaft and / or the corresponding mating part. In some examples, the locking means may be in constant contact with, for example, the inner shaft, but the force that clamps the inner shaft or any other member to be clamped for locking the rolling membrane may be significantly different between the two configurations of the locking means. Thus, the locking means provides a safety mechanism that prevents damage to the catheter and / or the blood vessel wall. This can generate user-friendly mechanical feedback to the user operating the catheter as to whether the inner member should be moved, which can improve safety.

[0009] In another example, the catheter may include at least one locking device, the locking device including an elastic element configured to change its configuration at least in part based on the fluid state of the catheter. This can result in a low-cost locking device that operates, for example, without any electrical devices, which can optimize reliability and / or safety. Additionally, the elastic element can be particularly suitable for maximizing the contact area with the surface of the member to be contacted and locked. The elastic element can be, for example, silicone, rubber, and / or any other elastic element, the shape of which is configured to change its configuration in response to a change in fluid state (e.g., changing fluid pressure). For example, it can be pre-tensioned. Such an element can be, for example, at least one elastic tubular member and / or ring that clamps the inner shaft of the catheter when a low fluid pressure is provided in the volume between the outer shaft and the inner shaft, thereby locking the inner shaft relative to the outer shaft and thus relative to the rolling membrane. The elastic element can be set under tension such that when no pressure is provided or a pressure below a predetermined threshold is provided, the elastic element clamps the inner shaft. In an example, when a higher fluid pressure is provided in the volume between the outer shaft and the inner shaft, it can further at least partially expand such that it lifts from the inner shaft (or the pressure applied to the inner shaft is reduced), thereby allowing movement of the inner shaft relative to the outer shaft and thus the rolling membrane. In an example, the elastic element can be at least one knob configured to change its configuration such that it locks or unlocks the rolling membrane according to its configuration that depends on the fluid state. In some examples, the elastic element can include at least one spring and / or spring-like element that can be configured to hold the locking element in the locked position unless sufficient fluid pressure is provided to the catheter to counteract the force of the spring and allow movement of the rolling membrane. In some examples, the elastic element can include an elastic layer having finger-like elements arranged to lock the inner shaft unless sufficient pressure is applied to lift the elastic layer from the inner shaft and thus lift the finger-like elements. Such an elastic device can be a robust, reliable, and safe solution suitable for integration into the catheter.

[0010] In some examples, the catheter may further include a fluid state sensor. At least one locking device can be in a locked and / or unlocked configuration at least in part based on the fluid state measured by the fluid state sensor provided to the catheter. In addition to any locking mechanisms described herein, a fluid sensor can also be provided to the catheter.

[0011] According to a second aspect of the present invention, there is provided a catheter including a rolling membrane that prevents the inadvertent advancement of a guide wire (i.e., an undesired advancement of the guide wire at a speed approximately twice the speed of the leading edge of the rolling membrane). This can be accomplished by using at least one decoupling device configured to decouple the movement of the rolling membrane from the movement of the guide wire or by using at least one motion compensation device configured to limit and compensate for the forward movement of the guide wire. Such a catheter includes a rolling membrane, a guide wire, and at least one decoupling device or at least one motion compensation device, the decoupling device being configured to decouple the movement of the rolling membrane from the movement of the guide wire, and the motion compensation device being configured to limit and compensate for the forward movement of the guide wire. Decoupling the movement of the rolling membrane from the movement of the guide wire can at least partially address some of the problems associated with the undesired guide wire advancement described herein. It can further increase safety and provide a user-friendly catheter. The guide wire can be used as a tool to guide the rolling membrane such that the guide wire can be introduced, for example, into a blood vessel to a treatment site (such as a stenosis site). The tubular rolling membrane can be everted with the guide wire to the treatment site and beyond the treatment site because it can encapsulate the guide wire such that its eversion is determined by the positioning of the guide wire. It may be advantageous to always be able to move the guide wire and the rolling membrane independently of each other. For this purpose, their movements can be at least partially decoupled.

[0012] At least one decoupling device can be any device that provides any mechanism capable of decoupling the movement of the guide wire and the rolling membrane. This separation can allow the movement of the rolling membrane when the guide wire is not moving and / or allow the movement of the guide wire when the rolling membrane is not moving. Additionally, the guide wire and the rolling membrane can move independently of each other simultaneously and / or continuously, for example, at different speeds, accelerations, and / or in different directions. The catheter can include at least one decoupling device, the decoupling device including a clamping element configured to restrict the movement of the guide wire, preferably in the longitudinal direction. Clamping the guide wire can be an effective decoupling mechanism suitable for overcoming the clamping force of the rolling membrane on the guide wire. Thus, it can increase safety.

[0013] The clamping element can be, for example, a mechanical clamp that clamps the guide wire via an interlock (e.g., in a form-fitting manner) and / or a friction-locking connection between the clamping element and the guide wire. For example, the clamping element can clamp the guide wire via at least two dies, locking screws, and / or notches configured to clamp the guide wire. Alternatively, the clamping element can be an elastic element (e.g., silicone or rubber) and / or any other elastic element whose shape is configured to change its configuration in response to a change in fluid state (e.g., changing fluid pressure). The clamping element can be tightened to clamp the guide wire once, or the clamping force can be adjusted to the clamping force required at that time. In an example, the clamping can be controlled by the user and / or it can be (semi)automatically controlled. The user can further be instructed to clamp the guide wire by the clamping element at least partially based on the fluid state and / or the motion state of the rolling membrane (e.g., as sensed by corresponding sensors).

[0014] In some examples, the catheter may include a decoupling device that includes at least one friction reducing element on the outer side of the rolling membrane. This may have the advantage of reducing the friction between the rolling membrane and the guide wire. Thus, when the rolling membrane is everted and / or retracted, the guide wire may remain stationary because the rolling membrane may apply a substantially weaker force to the guide wire. This may be further advantageous because the rolling membrane can be manipulated in this manner independently of any other component of the catheter.

[0015] The outer side of the rolling membrane is the side that contacts the vessel wall when the rolling membrane is fully everted and contacts the guide wire when it is fully retracted.

[0016] In some examples, when the rolling membrane is in the (fully) retracted state and fluid pressure is applied to the rolling membrane, the rolling membrane expands such that at least a portion of the outer side of the rolling membrane may contact at least a portion of the guide wire. The clamping force generated on the guide wire may depend on the contact area and the fluid pressure applied to the rolling membrane. Due to the clamping force and friction generated between the rolling membrane and the guide wire, the rolling membrane can drag the guide wire when it is everted or retracted. The force acting on the guide wire generally depends on the contact area, the normal force i.e., the clamping force, and the coefficient of friction, which is an empirical property of the two materials in contact with each other. The friction reducing element can reduce the coefficient of friction. This can reduce the force acting on the guide wire such that the force required to drag the guide wire with the rolling membrane is simply reduced and / or the force can be reduced to such an extent that the guide wire remains stationary when the rolling membrane is everted and / or retracted.

[0017] For example, the friction reducing element may include a hydrophilic portion. The friction reducing element may also, for example, include a film on the entire outer side of the rolling film, or it may only cover a part of the outer side of the rolling film. The friction reducing element may also be an integral part of the rolling film, such that, for example, the complete rolling film is composed of the friction reducing element and / or a section of the rolling film includes the friction reducing element. In some examples, the friction reducing element may cover a part of the outer side of the rolling film in the form of any pattern, which may be, for example, a stripe pattern, a dot pattern, or a checkerboard pattern. Such a pattern may further, for example, vary in length along the axial direction of the rolling film, for example to provide a spatially varying coefficient of friction that is adjusted to the corresponding contact area between the guide wire and the rolling film according to the respective everted state. For example, the first part of the rolling film to be everted may be provided with a friction reducing element because the contact area is larger when this part contacts the guide wire. The last part of the rolling film to be everted may be only partially covered with the friction reducing element, or may not be provided with the friction reducing element. This may be sufficient because when the rolling film is almost completely everted, the contact area is very small. Therefore, the frictional force may already be too small to drag the guide wire with the rolling film. Therefore, at this stage, friction reduction may no longer be required to decouple the movement of the rolling film and the guide wire. Generally, such a pattern may be adjusted in any way to customize the interaction between the rolling film and the guide wire. In some examples, the friction reducing element may include one or more polymers, liquid films, etc. The friction reducing element may further be adapted to be permanently applied to the rolling film such that no components detach from the rolling film and contaminate the treated lumen.

[0018] The at least one motion compensation device may include a torque element (also denoted as a guide wire torquer), and optionally an elastic body, preferably a spring (where the load is an axial force), such as a helical spring. This ensures that the advancement of the guide wire in the rolling film catheter is independent of the user and (cyclically) compensated, thus enhancing safety in a clinical environment. Optionally, the motion compensation device may be provided with automatic decompression. Accordingly, the at least one motion compensation member may further include a sealing element, preferably a ball valve or a sliding seal.

[0019] The catheter may include a first fluid inlet configured to be connected to a first fluid unit. The first fluid inlet may be configured to pressurize a clamping element for pressure control. The clamping element may be configured to clamp the guide wire when fluid pressure is provided to the first fluid inlet by the first fluid unit. For example, the clamping element may expand by fluid pressure and clamp the guide wire under fluid pressure. Control based on the fluid state may be an advantageous control system compatible with the necessary flexibility of the catheter. Additionally, it may provide the clamping force for clamping the guide wire (semi)-automatically and / or only when needed, thus increasing safety and improving catheter handling in a user-friendly manner.

[0020] The clamping element can be a mechanical clamp as described herein. Such a mechanical clamp can be activated to clamp the guide wire in a (semi)-automatic manner, e.g., as indicated by a control unit at least in part based on the fluid state sensed by a corresponding sensor. In some examples, the clamping element can be configured to respond directly to the pressure provided to it. For example, the clamping element can include an element that is configured to expand and / or otherwise change its configuration according to the pressure provided to it, e.g., by a fluid unit via a first fluid inlet. For example, when a pressure below a predetermined threshold is provided to the clamping element, it may not clamp the guide wire and / or when a fluid pressure above the predetermined threshold is provided to the clamping element, it may clamp the guide wire. The clamping element can, for example, include an (elastic) ring having an inner diameter placed around the guide wire. When pressure is provided to the outer side of the ring, the inner diameter can be reduced such that the guide wire is clamped, the guide wire cannot move, and the movement of the rolling membrane and the guide wire is thus decoupled. The guide wire can be released at any time by adjusting the pressure provided to the clamping element. Any function described with respect to the clamping element or any other function described herein can be implemented as steps of a method and / or instructions of a computer program.

[0021] The catheter can include a second fluid inlet configured to be connected to a first fluid unit and / or another fluid unit. The second fluid inlet can be configured to pressurize the rolling membrane. The first fluid unit can also be configured to determine the fluid state of the rolling membrane of the catheter. Using the same fluid unit to determine the fluid state of the rolling membrane and control the clamping element can simplify the system, make it more user-friendly, reduce material costs, and result in the clamping force being appropriately adjusted to the fluid state of the rolling membrane.

[0022] In some examples, different fluid units can be connected to the first inlet and the second inlet to separately control the two corresponding fluid states, which can be adjusted relative to each other for synchronized operation. The same fluid unit can be connected to the first fluid inlet and the second fluid inlet, thereby providing the same fluid state to both. In particular, the guide wire can thus be automatically (un)clamped when the membrane is (un)inflated. The first fluid inlet can connect the fluid unit to the clamping element and be activated by at least one parameter associated with the fluid state as described herein. The second fluid inlet can connect the fluid unit to the space between the outer shaft and the inner shaft of the catheter, which space is bounded by the rolling membrane at the distal end of the catheter and a sealing device at the proximal end of the catheter, and which space is referred to herein as the rolling membrane volume. The fluid state of the rolling membrane can be understood as the fluid state provided to the rolling membrane volume. In an example, when the fluid pressure is above a minimum value (and below the burst pressure), the rolling membrane can be considered to be in an inflated state, where in the case of the fluid pressure being below the minimum value, the rolling membrane is considered to be only partially inflated.

[0023] In some examples, at least one decoupling device or at least one motion compensation device of the catheter is at least partially arranged at a part of the catheter close to the rolling membrane. This can have the following advantages: The decoupling device can not interfere with the normal operation of the catheter, for example, the distal end of the catheter is inserted into the patient's body and / or the eversion of the rolling membrane. The decoupling device as described herein can be directly mounted to, for example, the proximal part of the outer shaft and / or the inner shaft. In some examples, the decoupling device can be connected to the proximal part of the outer shaft and / or the inner shaft via a frame and / or legs. The frame and / or legs can further extend in the proximal direction from the proximal region of the outer shaft to place the decoupling device proximally beyond the proximal end of the outer shaft. The frame and / or legs can have the shape of a bracket, and the bracket provides space for a device for controlling the movement of the inner shaft via a handle at the proximal end of the inner shaft.

[0024] In some examples, the catheter can include a third fluid inlet configured to be connected to a second fluid unit. The second fluid unit can be configured to provide fluid pressure to the volume between the rolling membrane and the guide wire. The second fluid pressure can have an advantageous effect because it counteracts the fluid pressure provided to the other side of the rolling membrane (rolling membrane volume) as described herein: for example, when the two pressures are adjusted accordingly to each other, the additional pressure provided by the second fluid unit can at least partially lift the rolling membrane off the guide wire (and / or at least reduce the clamping force between the rolling membrane and the guide wire). This can reduce the frictional force between the rolling membrane and the guide wire and thus decouple the movement of the rolling membrane and the guide wire. This can prevent the guide wire from advancing undesirably at twice the speed of the leading edge of the rolling membrane. The third fluid inlet can be configured to pressurize the volume between the inner shafts of the rolling membrane. In an example, the third fluid inlet can be located at the inner shaft, for example, at the proximal region of the inner shaft near the handle. In this way, it can not interfere with the operation of the catheter as described herein. Like any other fluid unit, the second fluid unit can be an external part or an integral part of the catheter system. It can be controlled by a healthcare professional or in a (semi) - automatic manner, for example, it can be adjusted at least partially based on the fluid state of the rolling membrane volume. In an example, the fluid pressure provided to the volume between the rolling membrane and the guide wire can be adjusted to the fluid pressure provided to the rolling membrane volume such that only a small part of the rolling membrane contacts the guide wire, for example, only along a loop at the distal end of the rolling membrane. This can reduce the frictional force to an extent sufficient to decouple the movement of the rolling membrane and the guide wire without having to open the lumen of the rolling membrane. The fluid pressure provided to the volume between the rolling membrane and the guide wire can be at least partially automatically adjusted at least partially based on the fluid pressure provided to the rolling membrane volume. This can be achieved, for example, by coupling two corresponding fluid units for synchronous operation or even using the same fluid unit for the corresponding fluid inlets.

[0025] In one aspect, a system can be provided that includes a rolling membrane catheter and at least one fluid unit as described herein. The fluid unit can be configured to provide fluid pressure to at least two of: a first fluid inlet, a second fluid inlet, and a third fluid inlet. Connecting one fluid unit to more than one inlet can provide a cost-effective and more user-friendly system. Additionally, it may be advantageous to provide the same fluid state to different devices, as their activation as described herein can be inherently coupled in an advantageously regulated manner. Furthermore, such a configuration provides high flexibility and the possibility to adapt the use of at least one fluid unit to the planned treatment and / or other patient-related factors. The at least one fluid unit can be connected to the respective inlets via a flexible hose or any other connecting device. The at least one fluid unit can be controlled by a health professional or in an automatic and / or semi-automatic manner.

[0026] According to a third aspect of the invention, a catheter including a rolling membrane is provided. The catheter can include at least one pressure relief valve and / or at least one friction reducing element on the inner side of the rolling membrane. In some examples, the at least one pressure relief valve can open when the fluid pressure exceeds a predetermined threshold. Thus, bursting of the rolling membrane can be prevented in a safe and user-friendly manner. The at least one pressure relief valve can be located, for example, at the proximal portion of the outer shaft.

[0027] In an example, in addition to or instead of the friction reducing element on the outer side of the rolling membrane, there can be a friction reducing element on the inner side of the rolling membrane. Furthermore, the friction reducing element on the inner side of the rolling membrane can have any of the characteristics described herein with reference to the friction reducing element on the outer side of the rolling membrane. The friction reducing element on the inner side of the rolling membrane can reduce the friction between two portions of the rolling membrane that are in contact with each other, for example when the rolling membrane is clamped in a stenosis such that it is not in its fully inflated state. When the portions in contact with each other can move relative to each other without significant friction (or at least reduced friction) provided by the friction reducing element, the rolling membrane can, for example, retract in a rolling motion without crimping / folding. The friction between two portions of the rolling membrane that are in contact with each other can be high, for example when no friction reducing element is available. In such an example, the retraction of one end of the rolling membrane (e.g., via retraction of the inner shaft) can drag the two contacting portions of the layer with it. This is incompatible with the intended rolling motion of the rolling membrane. Instead, the rolling membrane can be compressed and folded in the axial direction. By means of the friction reducing element, this problem can be avoided and correct winding of the membrane can be achieved even in difficult situations.

[0028] A fourth aspect of the present invention is the use of a tubular element as a rolling membrane of a rolling membrane catheter, the tubular element comprising a friction reducing element applied to at least a portion of the outer side of the tubular element and / or at least a portion of the inner side of the tubular element. The tubular element used as the rolling membrane may have any of the features described herein with respect to the rolling membrane, the friction reducing element, the catheter, and / or any other component of the catheter.

[0029] According to a fifth aspect of the present invention, a computer program comprising instructions may be provided such that when the program is executed, the program may cause a rolling membrane catheter to clamp a guide wire of the catheter by a clamping element so as to decouple the movement of the rolling membrane of the catheter from the movement of the guide wire. The computer program may comprise instructions implemented according to any of the features described herein, and further, any such instructions of the computer program may be implemented as steps of a corresponding method. Such a computer program may facilitate automation, improve reliability, reduce the risk of user error, and it may improve the overall handling and / or performance of the corresponding catheter. In some examples, such a computer program may be at least partially based on an artificial intelligence AI assistant as described herein. Such AI may recommend and / or determine at least one parameter associated with the operation of the catheter.

[0030] In another example, a computer program comprising instructions may be provided such that when the program is executed, it may cause a catheter (e.g., as described herein) to lock a rolling membrane at least partially based on the fluid state of the catheter. In some examples, when insufficient fluid pressure is provided to the catheter, it may cause at least one locking device of the rolling membrane catheter to be in a first configuration that locks the rolling membrane. Further, when sufficient fluid pressure is provided to the catheter, it may cause at least one locking device to be in a second configuration that unlocks the movement of the rolling membrane. This may involve, for example, a signal from a sensor sensing the fluid state of the rolling membrane volume. Wherein, the signaling may be at least partially based on at least one parameter associated with the fluid state of the rolling membrane volume. This may cause at least one locking device to contact the inner shaft, for example, in the case where at least one locking device may be at least partially connected to at least a portion of the outer shaft of the catheter (as described herein). When at least one locking device includes an elastic element, the instructions of the computer program, when executed, may cause the elastic element to change its configuration at least partially based on the fluid state of the catheter. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1A A schematic diagram of a rolling membrane catheter is schematically shown, having coupled rolling membrane and guide wire movement, and wherein the rolling membrane is in a partially everted state.

[0032] Figure 1BA schematic diagram of a rolling membrane catheter is shown schematically, which has a coupled rolling membrane and guidewire movement, and wherein the rolling membrane is in a further everted state, wherein the leading edge of the rolling membrane advances a distance x, and the inner member and the guidewire advance a distance 2x.

[0033] Figure 2A A schematic diagram of an outer shaft with an integrated locking device in the unlocked position is shown schematically.

[0034] Figure 2B A schematic diagram of an outer shaft with an integrated locking device in the locked position is shown schematically.

[0035] Figure 3A A schematic diagram of a rolling membrane catheter is shown schematically, the rolling membrane catheter having a decoupled rolling membrane and guidewire movement via a mechanical clamp, and wherein the rolling membrane is in a partially everted state.

[0036] Figure 3B A schematic diagram of a rolling membrane catheter is shown schematically, the rolling membrane catheter having a decoupled rolling membrane and guidewire movement via a mechanical clamp, and wherein the rolling membrane is in a further everted state, wherein the leading edge of the rolling membrane advances a distance x and the guidewire is locked.

[0037] Figure 4A A schematic diagram of a rolling membrane catheter is shown schematically, the rolling membrane catheter having a decoupled rolling membrane and guidewire movement via a pressure control clamp, and wherein the rolling membrane is in a partially everted state.

[0038] Figure 4B A schematic diagram of a rolling membrane catheter is shown schematically, the rolling membrane catheter having a decoupled rolling membrane and guidewire movement via a pressure control clamp, and wherein the rolling membrane is in a further everted state, wherein the leading edge of the rolling membrane advances a distance x and the guidewire is locked.

[0039] Figure 5A A schematic diagram of a rolling membrane catheter is shown schematically, the rolling membrane catheter having a decoupled rolling membrane and guidewire movement via a pressure control clamp, and wherein the rolling membrane is in a partially everted state, wherein fluid pressure is provided to the volume between the rolling membrane and the guidewire.

[0040] Figure 5B A schematic diagram of a rolling membrane catheter is shown schematically, the rolling membrane catheter having a decoupled rolling membrane and guidewire movement via a pressure control clamp, and wherein the rolling membrane is in a further everted state, wherein the leading edge of the rolling membrane advances a distance x, and the guidewire is locked, wherein fluid pressure is provided to the volume between the rolling membrane and the guidewire.

[0041] Figure 6A A schematic diagram of the retraction of a pressurized rolling membrane is shown schematically,

[0042] Figure 6BA schematic diagram showing the retraction of a non-pressurized rolling membrane is shown schematically.

[0043] Figures 7A to 7H A schematic diagram showing a rolling membrane catheter including a motion compensation device is shown schematically.

[0044] Figure 8A / 8B schematically shows a rolling membrane catheter including a motion compensation device with automatic decompression.

[0045] Figure 9A / 9B schematically shows a schematic diagram of another rolling membrane catheter including a motion compensation device with automatic decompression. Detailed Description

[0046] In this document, whenever mentioned, the distal direction and the proximal direction refer to the left direction and the right direction respectively in all the figures described below.

[0047] Figure 1A A schematic diagram of a rolling membrane catheter 100 is shown, in which the movements of the rolling membrane 120 and the guide wire 110 are coupled, and in which the rolling membrane 120 is in a partially everted state. The catheter includes an outer shaft 130 and an inner shaft 150. A second fluid inlet 140 is provided and configured to be connected to a fluid unit (not shown), and the fluid unit determines the fluid state of the rolling membrane 120 by providing, for example, fluid pressure to the rolling membrane volume defined by the rolling membrane 120, the outer shaft 130, and the inner shaft 150. Figure 1A The exemplary embodiment of also includes a handle 160 at the proximal end of the inner shaft 150. A health professional can move the inner shaft 150 relative to the outer shaft 130 through this handle 160. They can move the inner shaft 150 in the distal direction to evert the rolling membrane 120 and in the proximal direction to retract the rolling membrane 120. During both eversion and retraction, the rolling membrane 120 is ideally in an inflated state so that it everts and / or retracts during the rolling motion.

[0048] Figure 1B Shows Figure 1A An exemplary embodiment of the catheter 100 of, in which when the leading edge of the rolling membrane 120 advances a distance x, the rolling membrane 120 is in a further everted state via the movement of the inner shaft 150 in the distal direction. The inner shaft 150 is in a different position, offset by a distance of 2x compared to Figure 1A the case of. Compared to Figure 1A the position of the guide wire 110 shown, the guide wire 110 clamped by the rolling membrane 120 is also offset by a distance of 2x in the distal direction. Therefore, Figure 1B shows an exemplary scenario of the coupled movement of the guide wire 110 and the rolling membrane 120, which has the risk of the undesired advancement of the guide wire 110 into, for example, a blood vessel, which is one of the problems of the rolling membrane catheter 100.Figure 1A and Figure 1B together illustrate the basic working principle and basic building blocks of the rolling membrane catheter 100.

[0049] Figure 2A Shows a schematic view of the outer shaft 230 of the catheter 200, where the exemplary locking device 280 is in the unlocked position. The exemplary locking device 280 is integrated in the outer shaft 230. The locking device 280 may include an elastic ring or tube. The illustrated exemplary locking device 280 may include an elastic tubular element that is integrated as a part into the tubular outer shaft 230. In some examples, the elastic tubular element may be adjacent to the outer surface of the outer shaft 230. Figure 2A The unlocked position of the exemplary embodiment shown in causes the elastic ring of the locking device to be lifted away from the inner shaft 250 due to sufficient pressure provided to the volume between the outer shaft 230 and the inner shaft 250. Figure 2A The section shown in may be only a part of the entire outer shaft 230, and there may be multiple such locking devices 280 included in the outer shaft 230. The multiple locking devices may be the same or different, for example, different in length, material, and / or shape in the axial direction.

[0050] Figure 2B Shows Figure 2A a schematic view of an embodiment of, where the outer shaft 230 has an integrated locking device 280 in the locked position. The locking device 280 may be arranged around the outer shaft 230. Figure 2A The locked position of the exemplary embodiment shown in causes the elastic ring of the locking device not to be lifted from the inner shaft 250 due to insufficient pressure provided to the volume between the outer shaft 230 and the inner shaft 250. Thus, the locking device 180 clamps the inner shaft 250 and connects the outer shaft 230 and the inner shaft 250 such that they cannot move relative to each other. The locking device 280 may include forms other than tubular. For example, the locking device 280 may include at least one knob, piston, pin, and / or membrane. Any one of these locking devices 280 may be configured to be in the unlocked position when, for example, sufficient fluid pressure is provided to the catheter 200. In the unlocked position, the locking devices 280 are passive such that they do not lock any components of the catheter 200. Additionally, any locking device 280 may be configured to change its configuration as described herein, for example, when the fluid pressure provided to the catheter 200 is insufficient, to enter its active locking position of locking at least one component of the catheter 200.

[0051] Figure 3AA schematic view of a rolling membrane catheter 300 is shown, in which a rolling membrane 320 and a guide wire 310 move via a clamping element 37, and in which the rolling membrane is in a partially everted state. The clamping element 37 may extend further proximally from the proximal end of the outer shaft 330 and / or from the proximal end of a handpiece at the proximal end of the outer shaft 330. Figure 3A The clamping element 37 shown in may be a mechanical clamp 370, in which the guide wire 310 may be mechanically clamped via, for example, a locking screw. As an alternative or supplement to the shown locking screw, any other locking mechanism described herein is also possible. In addition, the catheter 300 includes a second fluid inlet 340, which is configured to be connected to a fluid unit (not shown) that determines the fluid state of the rolling membrane 320. The catheter further includes an inner shaft 350 and a handle 360.

[0052] Figure 3B Shows Figure 3A an exemplary embodiment of the catheter 300 of, in which the rolling membrane 320 is in a further everted state when the leading edge of the rolling membrane 320 advances a distance x. Compared with Figure 3A the case of, the inner shaft 350 is in a different position, for example, displaced a distance 2x via the handle 360. The guide wire 310 clamped by the rolling membrane 320 is clamped by the clamping element 37 such that it is in the same position as in Figure 3A because the clamping force of the clamping element 37 exceeds the clamping force of the rolling membrane 320. Therefore, Figure 3B shows an exemplary scenario of decoupled movement of the guide wire 310 and the rolling membrane 320, thereby reducing the risk of the undesired advancement of the guide wire 310 into, for example, a blood vessel.

[0053] Similar to Figure 3A , Figure 4A a schematic view of a rolling membrane catheter 400 is shown, in which a rolling membrane 420 and a guide wire 410 move via a clamping element 47, and in which the rolling membrane is in a partially everted state. Figure 4A The clamping element 47 shown is a pressure control clamp 470, in which the guide wire 410 is clamped via an elastic member that contacts the guide wire 410 to clamp the guide wire 410 when sufficient fluid pressure is provided to the clamp 470. The clamping element 47 may be arranged relative to the outer shaft 430 similarly to the clamping element 37 and the outer shaft 330 as outlined with reference to Figure 3A and Figure 3B . In addition, the catheter 400 includes a second fluid inlet 440, which is configured to be connected to a fluid unit that determines the fluid state of the rolling membrane 420. The catheter further includes an inner shaft 450 and a handle 460.

[0054] Similar to Figure 3B , Figure 4B shows Figure 4AAn exemplary embodiment of catheter 400, where when the leading edge of rolling membrane 420 advances a distance x, rolling membrane 420 is in a further everted state. Inner shaft 450 is in a different position, offset by a distance 2x compared to the Figure 4A case. The guide wire 410 clamped by rolling membrane 420 is also clamped by clamping element 47 such that it is in the same position as in Figure 4A because the clamping force of clamping element 47 exceeds the clamping force of rolling membrane 420. Thus, Figure 4B illustrates an exemplary scenario of the decoupled movement of guide wire 410 and rolling membrane 420, thereby reducing the risk of unwanted advancement of guide wire 410.

[0055] Figure 5A illustrates a schematic view of rolling membrane catheter 500, where rolling membrane 520 and guide wire 510 move via clamping element 57 (e.g., pressure control clamp 570), and where rolling membrane 520 is in a partially everted state, similar to the reference Figure 4A of rolling membrane catheter 500 outlined. However, catheter 500 further includes a fluid conduit leading to inner shaft 550 via handle 560. Thus, fluid pressure can be provided to the volume between rolling membrane 520 and guide wire 510. In this exemplary embodiment, all three fluid inlets of outer shaft 530, inner shaft 550, and pressure control clamp 570 can be connected to the same fluid unit. The fluid pressure provided to inner shaft 550 provides fluid pressure to the volume between rolling membrane 520 and guide wire 510, thereby lifting at least a portion of rolling membrane 520 away from guide wire 510. By adjusting the fluid pressure provided to Figure 5A both sides of rolling membrane 520 in, rolling membrane 520 contacts guide wire 510 only at a small portion at the distal end of rolling membrane 520. Additionally, catheter 500 includes a second fluid inlet 540 configured to connect to a fluid unit that determines the fluid state of rolling membrane 520.

[0056] Similar to Figure 3B and Figure 4B , Figure 5B illustrates Figure 5A an exemplary embodiment of catheter 500, where when the leading edge of rolling membrane 520 advances a distance x, rolling membrane 520 is in a further everted state. Compared to the Figure 5A case, inner shaft 550 is in a different position, e.g., offset by a distance 2x via handle 560. The guide wire 510 clamped by rolling membrane 520 is clamped by clamping element 57, and further, the friction between rolling membrane 520 and guide wire 510 is reduced such that it is in the same position as in Figure 5A because the clamping force of clamping element 57 exceeds the clamping force of rolling membrane 520. Thus, Figure 5BAn exemplary scenario showing the decoupled movement of the guide wire 510 and the rolling membrane 520 is presented, thus reducing the risk of unwanted advancement of the guide wire 510.

[0057] Figure 6A A schematic illustration of the retraction of the pressurized rolling membrane (filled with fluid) 620 of the rolling membrane catheter 600 during intussusception through the stenosis S is shown. When the stenosis S is as wide as in Figure 6A , the inner surfaces of the rolling membranes 620 do not contact each other, and the rolling membrane 620 can be retracted by retracting the inner shaft 650 in the proximal direction, as indicated by the straight dashed arrow. The circular dashed arrow indicates the rolling motion of the retraction of the rolling membrane 620, which is essentially the reverse motion of intussusception. At least one friction reducing element 621 on the inner side of the rolling membrane Figure 6A does not contribute to the retraction process shown. The catheter also includes an outer shaft 630.

[0058] Figure 6B A schematic representation of the retraction of the rolling membrane 620 having a friction reducing element 621 on the inner side during intussusception through a narrow stenosis S is shown. In the case where the rolling membrane 620 bursts, the stenosis S can collapse and become so narrow that the rolling membrane 620 will be clamped by the stenosis. The inner side of the rolling membrane 620 provided with at least one friction reducing element 621 (in the form of a coating and / or a membrane as shown by the dashed line in Figure 6B ) comes into contact. In the absence of the friction reducing element 621, the friction between the parts of the rolling membrane 620 may be high enough to prevent the controlled retraction of the rolling membrane 620. It may potentially kink or burst further. However, at least one friction reducing element 621 present in the exemplary embodiment of Figure 6B can allow the rolling membrane 620 to be retracted controllably in a rolling motion by retracting the inner shaft 650 relative to the outer shaft 630 in the proximal direction, as indicated by the straight dashed arrow. Similar to Figure 6A , the circular dashed arrow indicates the rolling motion of the retraction of the rolling membrane 620, which is essentially the reverse motion of intussusception. Thus, at least one friction reducing element 621 provides a safety measure in the case where it cannot prevent the bursting of the rolling membrane 620, such that the catheter 600 can still be safely retracted.

[0059] The advancement of the guidewire and the manual repeated retraction of the guidewire both depend on the user (physician). If not taken into account, there is a risk that the guidewire will advance uncontrollably into the distal vascular region during the unrolling of the rolling membrane, and thus there is a risk of vascular perforation in the patient. Under pressure, the rolling membrane of the rolling membrane catheter is ready to unroll, and the guidewire is clamped by the rolling membrane. When the inner shaft is advanced and the rolling membrane is unrolled without using the motion compensation member, the clamped guidewire also advances at twice the speed of the front part of the rolling membrane. The tip of the guidewire can be pushed far beyond the maximum allowable distal position. This potentially poses a safety risk.

[0060] The problem of the movement coupling of the rolling membrane and the guidewire can be solved by Figures 7A to 7H the rolling membrane shown in, the rolling membrane includes (at least) one motion compensation device 770, and the motion compensation device 770 is configured to limit and compensate the movement of the guidewire advancement. Figure 7A Figures 7 to 7I show schematic views of a rolling membrane catheter 700 having a coupled rolling membrane 720 and a guidewire 710. The rolling membrane catheter 700 includes an outer shaft 730 and an inner shaft 750. A fluid inlet 740 can be provided and configured to connect to a fluid unit (not shown), and the fluid unit determines the fluid state of the rolling membrane 720 and / or provides fluid pressure to the rolling membrane volume limited by the rolling membrane 720, the outer shaft 730, and the inner shaft 750. The rolling membrane catheter 700 may also include a handle at the proximal end of the inner shaft 750. The (mechanical, cyclic) motion compensation member 770 may include a torque element 790 and optionally an elastic body 780, preferably a spring. It can be seen that the guidewire 710 is coupled to the rolling membrane catheter 700 or the outer shaft 730 by means of the motion compensation device 770 (including a torque element and a helical spring here). The motion compensation device 770 may be located in the proximal region of the guidewire 710. D represents the maximum allowable distal position of the guidewire tip. By ensuring the advancement of the guidewire restricted distally in the rolling membrane catheter 700 and thus separating this task from the user (physician), this solution significantly improves patient safety in clinical use.

[0061] Under pressure (see Figure 7A ), the rolling membrane 720 of the rolling membrane catheter 700 is ready to unroll. The guidewire 710 is clamped by the rolling membrane 720. When the rolling membrane unrolls under pressure (see Figure 7B ), the maximum distal position of the guidewire is restricted by the spring path. However, the rolling path of the rolling membrane is also restricted by the coupling with the guidewire 710. If the pressure in the rolling membrane is temporarily reduced (see Figure 7C ), the guidewire 710 can move freely again. The spring force pushes it back to the initial proximal position. Return under pressure (see Figure 7D), the rolling membrane 720 of the rolling membrane catheter 700 is ready to be further unrolled. The guide wire 710 is again clamped by the rolling membrane 720. When the rolling membrane 720 continues to unroll under pressure, the maximum distal position of the guide wire 710 is again limited by the spring path (see Figure 7E ). The unrolling distance of the rolling membrane 720 is also again limited by its coupling to the guide wire 710. If the pressure in the rolling membrane 720 is again temporarily reduced (see Figure 7F ), the guide wire 710 can move freely again. It is pushed back to its initial proximal position by the spring force. As the rolling membrane 720 continues to unroll under pressure (see Figure 7G ), the maximum distal position of the guide wire 710 is limited by the spring path. When the rolling membrane 720 is (almost) fully unrolled (see Figure 7H ), the guide wire 710 can move freely again. The spring force pushes it back to its initial proximal position.

[0062] An alternative motion compensation device (not shown here) may include a torque element, but may not include an elastic body such as a spring. This allows the physician to control what he wants to do with maximum ease. In this case, the physician can place the guide wire and then advance the rolling membrane catheter over the guide wire until it reaches the stenosis, with the guide wire advancing distally as far as possible and safely. The torque element now advances over the guide wire against the arc on the handle and is fastened / locked there. The physician can now pull back the guide wire with the torque element as far as possible without the guide wire losing the path it has found. When the rolling membrane is unrolled, the torque element stops the guide wire at the farthest distal position previously determined by the physician as safe. (The physician must visually monitor that the wire does not take another branch). Optionally, Figures 7A to 7H the (mechanical, cyclic) motion compensation member of the rolling membrane catheter may be provided with automatic decompression, see ( Figure 8A / B and 9A / B).

[0063] Figure 8A and Figure 8B show a rolling membrane catheter 800, which includes a (mechanical, cyclic) motion compensation member 870 with automatic decompression. The rolling membrane catheter 800 also includes an outer shaft 830 and an inner shaft 850. A fluid inlet 840 can be provided and configured to be connected to a fluid unit (not shown), which determines the fluid state of the rolling membrane 820 and / or provides fluid pressure to the rolling membrane volume bounded by the rolling membrane 820, the outer shaft 830, and the inner shaft 850. The rolling membrane catheter 800 may also include a handle at the proximal end of the inner shaft 850. The (mechanical, cyclic) motion compensation member 870 may include a torque element 890 and optionally an elastic body 880, preferably a spring. This variant of automatic decompression uses a ball valve 860. The ball valve is sealed as long as it does not undergo any contact / force from the outside (see Figure 8A). When the rolling membrane 820 is unrolled under pressure, the maximum distal position of the guide wire 710 is limited by the spring path. The torque element 890 thus pushes the ball valve 860 inward, causing a small leak and reducing the internal pressure (see Figure 8A ). This reduces the friction between the rolling membrane 820 and the guide wire until the spring force on the torque element 890 is sufficient to pull the guide wire proximally. At the same time, the ball valve 860 seals, and pressure can be re-established in the rolling membrane 820 for the next rolling cycle, where the entire process is repeated.

[0064] Figure 9A and Figure 9B shows a rolling membrane catheter that includes a (mechanical, cyclic) motion compensation member with alternative automatic decompression. The rolling membrane catheter 900 also includes an outer shaft 930 and an inner shaft 950. A fluid inlet 940 may be provided and configured to connect to a fluid unit (not shown) that determines the fluid state of the rolling membrane 920 and / or provides fluid pressure to the rolling membrane volume bounded by the rolling membrane 920, the outer shaft 930, and the inner shaft 950. The rolling membrane catheter 900 may also include a handle at the proximal end of the inner shaft 950. The (mechanical, cyclic) motion compensation member 970 may include a torque element 990 and optionally an elastic body 980, preferably a spring. This variant of automatic decompression uses a tapered envelope as a sliding seal 960. As long as the non-tapered portion of the envelope is in the sliding seal 960, the (hydrophilic) sliding seal 960 is sealed (see Figure 9A ). When the rolling membrane 920 is unrolled under pressure, the maximum distal position of the guide wire 910 is limited by the spring path. Thus, the tapered portion of the envelope stops in the area of the sliding seal, creating a small leak and reducing the internal pressure (see FIG. 9b). This reduces the friction between the rolling membrane 920 and the guide wire 910 until the spring force at the torque element 990 is sufficient to pull the guide wire 910 proximally. At the same time, the sliding seal 960 seals, and pressure can be re-established in the rolling membrane 920 for the next rolling cycle, where the entire process is repeated.

Claims

1. A catheter (100, 200, 300, 400, 500, 600, 700, 800, 900), comprising: Rolling membranes (120, 320, 420, 520, 620, 720, 820, 920); Guide wires (110, 310, 410, 510, 710); At least one decoupling device configured to decouple the movement of the rolling membranes (120, 320, 420, 520, 620) from the movement of the guide wires (110, 310, 410, 510, 710, 810, 910); or at least one motion compensation device (770, 870) configured to limit and compensate for the movement of the advancement of the guide wire.

2. The catheter (100, 200, 300, 400, 500, 600) according to claim 1, wherein the at least one decoupling device comprises a clamping element (37, 47, 57), and the clamping element (37, 47, 57) is configured to restrict the movement of the guide wire (110, 310, 410, 510).

3. The catheter (100, 200, 300, 400, 500, 600) according to claim 1 or 2, wherein the at least one decoupling device comprises at least one friction reducing element on the outer side of the rolling membrane (120, 320, 420, 520, 620).

4. The catheter (100, 200, 300, 400, 500, 600) according to claim 2 or 3 citing claim 2, further comprising a first fluid inlet configured to be connected to a first fluid unit, wherein the clamping element (37, 47, 57) is configured to restrict the movement of the guide wire (110, 310, 410, 510) when fluid pressure is provided to the first fluid inlet through the first fluid unit.

5. The catheter (100, 200, 300, 400, 500, 600) according to claim 4, further comprising a second fluid inlet (130, 340, 440, 540) configured to be connected to the first fluid unit, wherein the first fluid unit is further configured to determine the fluid state of the rolling membrane (120, 320, 420, 520, 620), and optionally comprises a third fluid inlet configured to be connected to a second fluid unit, and the second fluid unit is configured to provide fluid pressure to the volume between the inner shaft of the rolling membrane (120, 320, 420, 520, 620) and the guide wire (110, 310, 410, 510).

6. The catheter (100, 200, 300, 400, 500, 600) according to any one of claims 1 to 5, wherein the at least one decoupling device or the at least one motion compensation device (770, 870, 970) is at least partially arranged at a portion of the catheter (100, 200, 300, 400, 500, 600) close to the rolling membrane (120, 320, 420, 520, 620).

7. The catheter (100, 200, 300, 400, 500, 600) according to claim 1, wherein the at least one motion compensation device (770, 870, 970) comprises a torque element (790, 890, 990) and an optional elastic body (780, 880, 980), the elastic body preferably being a spring.

8. The catheter (100, 200, 300, 400, 500, 600) according to any one of claims 1 to 6, wherein the at least one motion compensation device (770, 870, 970) further comprises a sealing element, the sealing element preferably being a ball valve (860) or a sliding seal (960).

9. The catheter (100, 200, 300, 400, 500, 600) according to any one of claims 1 to 6, comprising a rolling membrane (120, 320, 420, 520, 620); and at least one pressure relief valve and / or at least one friction reducing element (621), the at least one pressure relief valve being configured to open when the pressure provided to the volume of the rolling membrane (120, 320, 420, 520, 620) exceeds a predetermined threshold, the friction reducing element (621) being located on the inner side of the rolling membrane (120, 320, 420, 520, 620).

10. The catheter (100, 200, 300, 400, 500, 600) according to any one of claims 1 to 6 or 9, comprising a rolling membrane (120, 320, 420, 520, 620); and at least one locking device (280), the locking device (280) being configured to lock the rolling membrane (120, 320, 420, 520, 620) at least in part based on the fluid state of the catheter (100, 200, 300, 400, 500, 600).

11. The catheter (100, 200, 300, 400, 500, 600) according to claim 10, wherein the at least one locking device (280) is at least in part connected to at least a portion of the outer shaft (130) of the catheter (100, 200, 300, 400, 500, 600), and / or wherein the at least one locking device (280) comprises an elastic element configured to change its configuration at least in part based on the fluid state of the catheter (100, 200, 300, 400, 500, 600).

12. A catheter (100, 200, 300, 400, 500, 600) according to claim 10 or 11, wherein the at least one locking device (280) is configured to be in a first configuration for locking the rolling membrane (120, 320, 420, 520, 620) when insufficient fluid pressure is provided to the catheter (100, 200, 300, 400, 500, 600), and to be in a second configuration for unlocking the rolling membrane (120, 320, 420, 520, 620) when sufficient fluid pressure is provided to the catheter (100, 200, 300, 400, 500, 600).

13. A system comprising a catheter (100, 200, 300, 400, 500, 600) according to claim 5 or claim 6 as referred to claim 5 and at least one fluid unit, wherein the at least one fluid unit is configured to provide fluid pressure to at least two of the following: the first fluid inlet, the second fluid inlet and the third fluid inlet.

14. A tubular element comprising a friction reducing element applied to at least a portion of an outer side of the tubular element and / or at least a portion of an inner side of the tubular element for use as a rolling membrane (120, 320, 420, 520, 620) in a rolling membrane conduit (100, 200, 300, 400, 500, 600).

15. A computer program comprising instructions which, when executed, cause the rolling membrane catheter (100, 200, 300, 400, 500, 600) according to any one of claims 5 to 6 or 12 to clamp the guide wire (110, 310, 410, 510) so as to decouple the movement of the rolling membrane (120, 320, 420, 520, 620) from the movement of the guide wire (110, 310, 410, 510).

Images