Optimized design of rolling film as guiding extension conduitTechnical Field
The present invention relates to different types of guide extension catheters and methods of use thereof.
Background
Changing living environments (e.g., intense daily life, unhealthy nutritional habits, lack of exercise, smoking, etc.) have resulted in an increase in coronary and/or arterial related diseases over the course of the last few years. These diseases may often result in dangerous effects on the health status of the patient (e.g., stenosis and/or occlusion of blood vessels) and may in some cases worsen, resulting in increased mortality of the affected patient.
In order to avoid life threatening situations, it may be important to diagnose the respective disease at an early stage of the disease and/or to allow the disease to be cured, wherein the risk of the patient should preferably be as low as possible.
Preferred minimally invasive methods to support early diagnosis and/or cure of such diseases are based on the use of catheters. In most cases, the catheter may be implemented as a tubular shaped, hose-like device that may be inserted into the body of the patient and may be moved along an artery and/or vein until a general abnormality (e.g., stenosis) in the patient's blood vessel.
Such catheters may be adapted to deliver medical devices (e.g., balloons, stents, etc.) and/or drugs to affected areas of a patient's blood vessel to diagnose and/or cure the corresponding disease.
In some cases, forward movement of the catheter (e.g., in the distal direction) and/or rearward movement of the catheter (e.g., in the proximal direction) may become difficult, especially if the vessel is occluded (e.g., calcified) and/or tortuous.
For example, in complex Percutaneous Coronary Interventions (PCI), one of the biggest challenges is the inability to pass lesions through catheters and/or medical devices and/or medical drugs to target lesions. In such cases, partner guidewire and/or anchoring balloon techniques may aid in successful completion of the coronary intervention.
Mother-son technology is another powerful method for delivering medical devices to a certain target lesion. In view of the mother-son technique, the insertion of a 4-French (Fr) catheter into a 6-Fr guide catheter (mother catheter) can greatly increase the success rate of passing through lesions that may fail the standard procedure. Thus, the "4 in 6" system is also becoming a viable alternative to highly calcified, angular or tortuous lesions.
In addition, quick change Guide Extension Catheters (GECs) or guide catheter extensions have been developed in this regard. Previous studies have proposed mechanisms for their efficiency as adding backup support through deep cannulas, as tubing to reduce friction between the vessel wall and the catheter, or for improving coaxial alignment between the catheter and the lesion. It also facilitates stent and balloon delivery in complex coronary lesions, complex anatomy, and/or left internal thoracic artery grafts.
For Percutaneous Transluminal Coronary Angioplasty (PTCA), a guide catheter is typically inserted into an access sheath with a guidewire, which once in place is pushed out of the guide catheter and into the coronary artery and through the stenosis, and then a guide extension catheter is introduced into the guide catheter and through the guidewire to find its way into the vessel.
The guide extension catheter may be a monorail system. The guide extension has an average length of 25cm and it can pass in a rapid exchange manner and can extend beyond the distal end of the guide catheter. The guide extension catheter may be thinner than the guide catheter, for example 1Fr, and it may be designed to minimize trauma to the coronary arteries. The proximal end of the guide extension catheter may be attached to a thin stainless steel push rod, which may be used to push and pull the guide extension catheter independently of the guide catheter.
However, even modern guiding extension catheters are still difficult to pass through calcified arteries, especially when 180 ° bends are present, due to excessive friction. The physician may then use the balloon catheter to help guide the extension catheter through such a bend. The procedure requires placing a balloon distal to the guide extension catheter, then inflating the balloon, and then pushing the guide catheter over the balloon catheter while deflating the balloon catheter. However, in some cases, the balloon catheter and guide catheter may move relative to the vessel wall and may cause intimal damage due to excessive shear.
In summary, if a strongly curved vessel needs to be studied by means of a catheter, existing catheters may be limited in their application and may pose an excessive risk to the health status of the patient and may excessively prolong catheter-based interventions.
Thus, there is a need to improve upon currently existing catheters, particularly guide extension catheters.
These drawbacks are at least partially overcome by a guiding extension catheter according to claim 1, 15 or 20.
Disclosure of Invention
The (rolling membrane) guiding extension catheter according to the invention comprises a rolling membrane and an outer shaft (e.g. a guiding catheter).
According to a first aspect of the invention, the guiding extension catheter comprises or consists of a rolling diaphragm, an outer shaft, an inner shaft at least partially arranged or arrangeable within the outer shaft, and wherein the rolling diaphragm is connected to the inner shaft and optionally a connecting element for (at least temporarily) connecting the rolling diaphragm to the outer shaft.
The first portion of the rolling membrane is connected to the inner shaft, and the catheter further comprises a connecting element for temporarily (e.g. releasably) connecting the second portion of the rolling membrane to the outer shaft.
The rolling film may be adapted to roll out in a distal direction. The rolling membrane may be adapted to roll in a proximal direction. The rolling film may be configured such that the rolling film extends in the longitudinal direction to a greater extent than it extends in the radial direction (i.e., a direction perpendicular to the longitudinal direction along which the rolling film is rolled).
In some embodiments, the first portion of the rolling film may be the distal end of the rolling film if the rolling film is fully rolled out. Thus, the rolling membrane may be configured to exit the outer shaft in a distal direction. Additionally or alternatively, the second portion of the rolling membrane may be a proximal portion of the rolling membrane if the rolling membrane is fully rolled in.
In some preferred embodiments, the outer shaft may be a guide catheter.
The connecting element is connected to the proximal portion of the rolling membrane and/or the connecting element is adapted such that the connecting element is connectable to the outer shaft.
By providing the catheter with a connecting element for temporarily connecting the proximal portion of the rolling membrane to the outer shaft, a contextually and non-permanently extending of the catheter can be facilitated. This may advantageously increase the field of possible applications for which the catheter may be used. For example, if the catheter may not be able to pass through a lesion in a patient's blood vessel, the catheter may additionally be provided with a suitable extension (e.g. by means of an outer shaft and a connecting element to connect the rolling membrane) so that the lesion may be passed through without damaging the inner wall of the respective blood vessel of the patient. In combination with a rolling membrane that may be adapted to safely and atraumatically propagate along a patient's blood vessel, the connected rolling membrane may be utilized to facilitate a guide extension catheter that may be released in an undesirable situation. For example, in case the film cannot be completely rolled out, it may be useful to make a (releasable) connection at this (proximal) end of the film (which would be distal if the film were completely rolled out).
The connecting element may be adapted to be inserted into the outer shaft and to establish a connection between the rolling diaphragm and the outer shaft. The connecting element can be connected to the rolling membrane by clamping. In some examples, welding, gluing, etc. may also be used. The connection between the rolling membrane and the outer shaft may be liquid and/or fluid tight.
The connecting element and the rolling membrane may be made of the same material (combination). Alternatively, the connecting element and the rolling membrane may differ in at least one constituent material.
The connection between the connecting element and the rolling membrane may be temporary. However, in some examples, the connection between the connecting element and the rolling membrane may be permanent.
The connecting element may include a first diameter at the proximal portion of the connecting element and a second diameter at the distal portion of the connecting element, the first diameter may be equal to or less than the inner diameter of the outer shaft, and the second diameter may be less than the first diameter at the proximal portion of the connecting element. This may enable a force fit of the connecting element with the outer shaft.
The ease of insertion and sliding characteristics of the coupling element into and within the outer shaft may be facilitated if the first diameter of the proximal portion of the coupling element is adapted to be smaller than the inner diameter of the outer shaft. This may contribute to the simplicity and overall convenient usability of the catheter.
Alternatively, the first diameter may be adapted to be larger than the inner diameter of the outer shaft. At least the proximal end portion of the connecting element may be adapted to be flexible such that the proximal end portion of the connecting element may be slightly compressed before inserting the connecting element into the lumen of the outer shaft. Since at least the proximal end portion of the connecting element may try to relax back to its original diameter, a pushing force may be applied to the inner wall of the outer shaft, which pushing force may be accompanied by friction/shear forces, so that the connecting element may be locked in the outer shaft, preferably by clamping.
By making the distal portion of the connecting element smaller in diameter than the corresponding proximal portion, easy insertion of the connecting element into the outer shaft may be facilitated.
The connecting element may be connected to the distal portion of the rolling membrane.
The connecting element, preferably the proximal (proximal) portion of the connecting element, may be connected to the distal (distal) portion of the rolling membrane. The proximal (proximal) portion of the rolling membrane may be connected to the inner shaft. Additionally or alternatively, the distal end portion of the connecting element may be connected to the rolling membrane. The connecting element may generally be provided with an inner cavity.
By adapting the connecting element such that it is connectable to the distal portion of the rolling membrane, preferably at the proximal end portion of the connecting element, it may be facilitated that the rolling membrane is at least partially accommodated in the lumen of the connecting element. This may help to protect the rolling membrane if the catheter needs to exert a certain pushing force in distal direction to pass the (micro) occlusion without damaging the rolling membrane.
The connecting element may comprise an annular element for applying a radial force to the distal portion of the rolling diaphragm and the outer side of the outer shaft or the inner side of the outer shaft.
The annular element may be provided as a ring. The annular element may comprise a slideway. The annular element may comprise a diameter that is larger than the inner diameter of the outer shaft. By pressing the annular element in a radial direction, the diameter of the annular element may be reducible.
By inserting the ring element into the inner cavity of the outer shaft and placing a portion of the rolling diaphragm between the ring and the inner side of the outer shaft, the ring may exhibit a radial force on the rolling diaphragm and the inner side of the outer shaft, thereby locking the rolling diaphragm in the outer shaft.
The connecting element may be adapted to be placed on the outer shaft and to establish a clamping connection between the rolling diaphragm and the outer shaft.
The annular element may comprise a diameter smaller than the outer diameter of the outer shaft. The ring element may thus tend to reduce its diameter when placed on the outer shaft, and may thus exhibit radial forces on the outer side of the outer shaft, which may advantageously be used for clamping the rolling diaphragm to the outer side of the outer shaft.
By adapting the connecting element such that it can be placed on the outer shaft, the rolling diaphragm can be clamped on the outer side of the outer shaft. With this configuration, insertion of medical equipment (as will be described further below) from the lumen of the outer shaft into the rolling membrane may be supported.
The connecting element may comprise a hydrophilic coating and/or an expandable coating so as to expand if exposed to a liquid. If the connecting element is inserted into the lumen of the outer shaft, the coating may be located between the connecting element and the inner side of the outer shaft.
The hydrophilic coating may be a hydrogel (e.g., polyvinylpyrrolidone). The coating may exhibit sealing capability at least when exposed to a liquid such that, for example, liquid is prevented from passing through if the coating is in contact with at least one other contact surface.
By providing the connecting element with a hydrophilic coating, the connecting element can be moved/slid to a desired target position without being affected by friction if the expandable liquid has been exposed to the liquid. Thus, a single coating may provide two advantageous effects, sealing capability, while still supporting the movability of the connecting element.
The rolling membrane may also comprise a sealing element, preferably a haemostatic valve, at its proximal portion.
By providing the rolling membrane with a hemostatic valve at a proximal portion of the rolling membrane, a firm and sterile insertion of the medical device into the lumen of the rolling membrane may be facilitated. Alternatively, the fluid supply to the rolling membrane may be facilitated, allowing for expansion of the rolling membrane.
The catheter may further comprise an actuating element for actuating the sealing element. The actuating element can be inserted into the lumen of the rolling membrane from the proximal direction.
The handling element may be adapted to push the sealing element in a distal direction (from a proximal direction). Additionally or alternatively, the handling element may be adapted to pull the sealing element in a proximal direction (from the proximal direction). Additionally or alternatively, the handling element may be adapted to be rotatable about its longitudinal axis, for example in order to rotate the sealing element.
The steering element may allow steering the sealing element from a remote location (e.g., from outside the patient), which may facilitate simplified steering of the catheter, particularly when inserted into the patient.
The sealing element may be adjustable in diameter by means of an actuating element.
The sealing element may be provided with a variable diameter. The variable diameter of the sealing element may be mechanically manipulated. The sealing element may be remotely manipulated from outside the patient.
By providing the sealing element in an adaptable manner, the sealing element can be easily adapted to the situation needs. For example, when the sealing element is to be inserted into, for example, an outer shaft, the sealing element may be set to a small diameter such that the sealing element does not unintentionally obstruct the insertion. However, when the sealing element has been successfully inserted into, for example, an outer shaft and pushed to a desired target location, the diameter of the sealing element may be increased so that the desired sealing performance is exhibited.
The rolling film may be adapted to form an inner cavity at least when the rolling film is in the rolled-out state.
If the rolling membrane is in an at least partially rolled state, the inner cavity of the rolling membrane can be effectively occupied by the rolling membrane folded therein. In some exemplary implementations, the inner shaft may not enter the lumen of the rolling film when the rolling film is in the rolled-out state.
Forming a lumen in the rolling membrane may allow for the delivery of a medical device (e.g., another catheter and/or stent, etc.) and/or medical drug to a target site, which may preferably be distal to the distal-most tip of the rolling membrane. Delivery may preferably be based on inserting the device and/or the drug to be delivered into the lumen of the rolling membrane from the proximal direction of the rolling membrane and pushing the device and/or the drug in the distal direction, as seen when the rolling membrane is fully rolled out.
The connecting element may be adapted to pressure tightly seal the expandable volume of the rolling diaphragm.
A pressure-tight seal may be understood as a seal that may not allow fluid particles to penetrate from, for example, a volume proximal to the connecting element to a volume distal to the connecting element up to a certain threshold pressure.
If the connection between the rolling membrane and the outer shaft is adapted for pressure sealing and/or fluid sealing, the rolling membrane may be inflatable, e.g. from the proximal direction of the connecting element, e.g. by supplying a pressurized liquid and/or gas. By means of the connecting element, the rolling membrane may in particular be inflatable if combined with the outer shaft.
A second aspect of the invention relates to a method for using a guide extension catheter, preferably a catheter as described above. The method may include providing an outer shaft and providing a rolling membrane connected to the inner shaft at a first portion of the rolling membrane. The method may further comprise releasably/temporarily connecting the second portion of the rolling membrane to the outer shaft, preferably via a connecting element, such that the rolling membrane can be rolled out along the longitudinal axis of the outer shaft.
By means of the above-described method, the catheter can be adapted more simply to the situation needs, even when partially inserted into the blood vessel of the patient.
The method may further include inserting the distal end of the outer shaft into the blood vessel and at least partially rolling out the distal end of the rolling membrane along the blood vessel such that a lumen may be formed in the rolling membrane to facilitate delivery of the medical device and/or medical drug from the proximal end of the rolling membrane to the distal end of the rolling membrane.
By operating the catheter according to the aforementioned method, the synergistic effect of the extension catheter and the rolling membrane can be advantageously used. This may improve the user experience of the members of the medical staff and may reduce the risk of the patient, for example due to movement of the catheter in the distal direction.
A third aspect of the invention relates to a guide extension catheter comprising or consisting of a rolling diaphragm, a proximal shaft and an outer shaft, preferably a guide catheter. The proximal shaft may be considered as an inner shaft which is arranged partly within the outer shaft, preferably within the guiding catheter. The proximal shaft may include a lumen.
The rolling film includes a first portion and a second portion. The first portion may be disposed at a distal end of the rolling membrane and the second portion may be disposed at a proximal end of the rolling membrane. The rolling membrane may be configured to form an inner rolling membrane lumen in a rolled-in state and/or a rolled-out state of the rolling membrane. The inner rolling membrane lumen has a larger diameter than the conventional inner shaft. Thus, the diameter of the rolling membrane lumen enables guiding (medical and/or sensing) equipment through the rolling membrane lumen (e.g. whenever the rolling membrane function is not required).
The proximal shaft may be connected to the second portion of the rolling diaphragm. Preferably, the proximal shaft may be connected to the rolling membrane such that the proximal shaft at least partially accommodates the second end of the rolling membrane in the lumen of the proximal shaft. In other words, the rolling membrane may be connected to the inside of the proximal shaft. Thus, the proximal shaft may not limit the inner diameter of the inner rolling membrane lumen. The proximal shaft may have a push-pull function, i.e. pushing the rolling membrane in the distal direction (towards the patient) and pulling the rolling membrane in the proximal direction (towards the operator/doctor).
The outer shaft, preferably the guiding catheter, may be adapted to at least partially enter the body of the patient with a portion I of the outer shaft. The outer shaft, preferably the guiding catheter, may further be adapted to be at least partially retained outside the patient's body with a portion of the outer shaft.
The diameter of the outer shaft (preferably the guiding catheter) may be increased at its proximal portion (at the portion O resting outside the body) compared to its distal portion. The diameter of the guide catheter may be increased at its proximal portion such that the proximal shaft cannot enter the distal portion of the guide catheter. Because the outer shaft (preferably the guide catheter) has a smaller diameter at its distal portion than at its proximal portion, it impedes insertion of the proximal shaft into the distal portion of the outer shaft. Thus, the length of the rolling membrane in the rolled-out state away from the outer shaft (preferably the guiding catheter) may be defined by the length of a distal portion of the outer shaft (preferably the guiding catheter), which distal portion has a smaller diameter than a proximal portion of the outer shaft. The proximal shaft may be adapted to remain outside the patient during use of the catheter with the patient. In other words, the proximal shaft may be adapted not to enter the body of the patient.
The rolling film may be adapted to roll out in a distal direction. The rolling membrane may be adapted to roll in a proximal direction. The rolling film may be configured such that the rolling film extends in the longitudinal direction to a greater extent than it extends in the radial direction. In some embodiments, the first portion of the rolling film may be the distal end of the rolling film if the rolling film is fully rolled out. Thus, the rolling membrane is configured to leave the outer shaft, preferably the guiding catheter, in the distal direction.
An outer shaft, preferably a guide catheter, accommodates at least a portion of the rolling diaphragm. At least a distal portion of the outer shaft, preferably the guiding catheter, may be connected to the first portion of the rolling membrane.
The proximal shaft may be adapted to push the rolling membrane in the distal direction D and/or to pull the rolling membrane in the proximal direction P. The lumen of the proximal shaft may be connected to the lumen of the rolling membrane so that, for example, medical devices and/or medical drugs may be fed from the proximal portion of the catheter to the distal portion of the catheter.
The rolling membrane may have a smaller wall thickness than the inner shaft. Thus, it is less damaging to the inner rolling membrane lumen than the conventional inner shaft.
The proximal end of the rolling membrane may be connected to the inner side of the proximal shaft, and wherein the distal end of the rolling membrane may be connected to the outer shaft, preferably to the guiding catheter. The outer shaft may house at least a portion of the rolling diaphragm.
At the proximal portion of the outer shaft (preferably the guiding catheter), the outer shaft may terminate in a sealing element. The sealing element may preferably be a haemostatic valve. The proximal shaft may extend at least partially through the sealing element.
A fourth aspect of the invention relates to a guide extension catheter comprising or consisting of a rolling diaphragm, an outer shaft (e.g., a guide catheter), the rolling diaphragm extending partially through the outer shaft, and wherein a proximal portion of the rolling diaphragm is slidably connected to a sealing valve and a distal portion of the rolling diaphragm is connected to a connecting element.
The sealing valve and/or the connecting element may comprise a hydrophilic coating and/or an expandable coating to expand upon exposure to a liquid. The sealing valve may comprise at least one haemostatic valve, for example the sealing valve may be a Tuohy Borst valve.
The sealing valve may be limited in its distal movement by an outer catheter. For example, the distal end of the sealing valve and the proximal end of the outer catheter may form a positive connection (form-fit connection). To connect the outer shaft to the valve 611, the valve may include a shaft-shaped portion that points in a distal direction and includes an outer diameter that is slightly smaller in diameter than the inner diameter of the outer shaft. The shaft-shaped portion may be provided with an inner diameter of at least 4 Fr.
The outer shaft may be movably arranged on the rolling membrane. The outer shaft may be movable in a proximal direction, wherein the connecting element may (further) enter the outer shaft in a distal direction due to translation of the outer shaft. Said sliding movement of the connecting element may advantageously be supported by a preferably hydrophilic coating of the connecting element, which hydrophilic coating may reduce friction during sliding translation.
The rolling membrane may extend through a sealing valve (e.g., a Tuohy Borst valve). In some embodiments, the rolling membrane may be connected to a proximal shaft in a proximal portion of the rolling membrane.
The connecting element may be adapted to seal the distal portion of the catheter.
The guide extension catheter according to the present invention may synergistically combine the advantages of a guide extension catheter (as described above) and a rolling membrane for improving the catheter-based invention as described above.
The catheter may further comprise an outer shaft at least partially enclosing the rolling membrane, wherein at least a proximal portion of the outer shaft remains outside the patient during use of the catheter with the patient.
Drawings
The following drawings are provided to support an understanding of the present invention:
FIGS. 1A-1B are illustrations of an exemplary rolling film catheter without an inner shaft;
FIGS. 2A-2C are illustrations of an exemplary rolling membrane catheter having an inner shaft and an additional connecting element;
FIGS. 3A-3B are illustrations of an exemplary rolling membrane catheter having an inner shaft and an additional connecting element;
FIG. 4 is a diagram of exemplary components of a rolling film guide extension catheter;
FIG. 5 is a diagram of an exemplary combination of an outer shaft and a rolling diaphragm catheter;
figures 6A-6B are illustrations of an assembled rolling film guide extension catheter.
Detailed Description
Fig. 1A and 1B depict a first exemplary embodiment of a rolling film catheter in accordance with an aspect of the present invention.
Fig. 1A shows an exemplary embodiment of a catheter 100, the catheter 100 comprising a rolling membrane 101 (depicted in a rolled state). The rolling film 101 includes a first portion 102 and a second portion 103. The first portion 102 may be arranged in a distal portion of the rolling film 101, while the second portion 103 may be arranged in a proximal portion of the rolling film 101. The rolling film 101 may be configured to form the inner cavity 104 in a rolled-in state of the rolling film 101 and/or in a rolled-out state of the rolling film 101.
Catheter 100 may also include an outer shaft 105, and outer shaft 105 may house at least a portion of rolling diaphragm 101. The outer shaft 105 may be a guide catheter. The outer shaft 105 may be adapted to at least partially enter the patient's body using a portion I of the outer shaft 105. The outer shaft 105 may further be adapted to be at least partially retained outside the patient's body with a portion O of the outer shaft 105. The diameter of the outer shaft 105 may be increased at its proximal portion (at the portion O left outside the body) compared to its distal portion.
At least a distal portion of the outer shaft 105 may be connected to the first portion 102 of the rolling membrane 101. At a proximal portion of the outer shaft 105, the outer shaft 105 may terminate in a sealing element 106. The sealing element 106 may preferably be a hemostatic valve.
Catheter 100 may also include a proximal shaft 107. The proximal shaft 107 may extend at least partially through the sealing element 106. The proximal shaft 107 may include a lumen. The proximal shaft 107 may be connected to the second portion 103 of the rolling diaphragm 101. Preferably, the proximal shaft 107 may be connected to the rolling membrane 101 such that the proximal shaft 107 at least partially accommodates the second end 103 of the rolling membrane 101 in the lumen of the proximal shaft 107. In other words, the rolling membrane 101 may be connected to the inside of the proximal shaft 107. Thus, the proximal shaft 107 may not limit the inner diameter of the lumen 104 of the rolling diaphragm 101, and thus the inner diameter of the outer shaft (guide catheter) 105 itself.
The proximal shaft 107 may be adapted to remain outside the patient's body at all times, preferably in part O. The proximal shaft 107 may be adapted to push the rolling membrane 101 in the distal direction D and/or to pull the rolling membrane 101 in the proximal direction P. The lumen of the proximal shaft 107 may be connected to the lumen 104 of the rolling membrane 101 such that, for example, medical devices and/or medical drugs may be fed from the proximal portion of the catheter 100 to the distal portion of the catheter 100.
Fig. 1B shows an exemplary embodiment of the catheter 100 of fig. 1A, wherein the rolling film 101 has been fully rolled out in the distal direction D. The proximal shaft 107 may be retained within the outer shaft 105, particularly a portion of the outer shaft 105 that is external to the patient and may have an increased diameter.
Fig. 2A-B illustrate another embodiment of a catheter 200 according to an aspect of the present invention.
Notably, fig. 2A shows the outer shaft 205 in combination with the rolling diaphragm 201 for forming a rolling diaphragm guide extension catheter (RMGCE). The rolling film 201 may be provided with a length of between 1cm and 30cm (as seen in the fully rolled-out state of the rolling film 201).
The rolling membrane 201 may be connected to the inner shaft 208. The rolling membrane 201 may be connected to the inner shaft 208 in a distal portion of the inner shaft 208. The rolling membrane 201 may be connected to the inner shaft 208 at the outer side of the inner shaft 208. The rolling membrane 201 may be connected to the inner shaft 208 by welding, gluing, clamping and/or any other suitable method.
The catheter may also include a connecting element 209. The connection element 209 may be provided as a ring element, for example a ring such as a circlip 210, as exemplarily depicted in fig. 2C. In some exemplary embodiments, the connecting element 209 may be implemented as a resilient bracket-like structure. In some exemplary embodiments, the connection element 209 may be provided as a spring sealing element.
The connection element 209 may be placed at a distance from the distal end of the outer shaft 205 to allow the rolling diaphragm 201 to self-seal against the inside of the outer shaft 205. If the connection element 209 is provided as a spring sealing element, the spring sealing element must ensure a sufficient pressure loss for any liquid passing between the spring element and the outer shaft 205 (e.g. the guiding catheter) such that the pressure within the expandable volume of the rolling membrane 201 is higher than the pressure on the outer side of the rolling membrane 201.
The connecting element 209 may preferably be adapted to be slidable within the lumen of the outer shaft 205 and then secured therein. Alternatively, the connecting element 209 may also be adapted to be placed on the outside of the outer shaft 205 and clamp the rolling diaphragm 201 to the outer shaft 205.
In an exemplary embodiment of the catheter 200, when the rolling membrane 201 is fully rolled out, the portion of the rolling membrane 201 in contact with the connecting element 209 may form the proximal end of the rolling membrane. The inner shaft 208 may bring the portion of the rolling membrane 201 connected to the inner shaft 208 to a distal-most position.
Fig. 2B shows the outer shaft 205 and the connecting element 209 connected, wherein the connecting element 209 is adapted to be inserted into the lumen of the outer shaft 205. The connecting element is connected to the distal portion of the outer shaft.
The connecting element 209 may be provided as a ring element (as described above with reference to fig. 2A) and may be provided with a diameter that may be greater than the inner diameter of the outer shaft 205. When the connection element 209 is inserted into the lumen of the outer shaft 205, the connection element 209 may exert a force on the rolling diaphragm 201 and the inner side of the outer shaft 205 such that the rolling diaphragm 201 is at least temporarily connected to the outer shaft 205.
Fig. 3A and 3B depict another exemplary embodiment of a connecting element 309. The connecting element 309 is attached to the distal portion of the rolling membrane 301, and the proximal portion of the rolling membrane is preferably attached proximally to the inner shaft 308.
Fig. 3A shows an exemplary illustration of a connecting element 309 according to another aspect of the invention. In this exemplary embodiment, the connecting element 309 may be provided as a funnel-shaped element, which may include a first diameter at a proximal portion of the connecting element 309, which may be less than or equal to the inner diameter of the outer shaft 305 (in a resting state, i.e., in a state in which the connecting element 309 is not connected to the outer shaft 305).
Fig. 3B illustrates an exemplary combination of the outer shaft 305 and the connecting element 309, the outer shaft 305 may be configured as described above. The connecting element 309 may be inserted into the lumen of the outer shaft 305. The connecting element is connected to the proximal portion of the outer shaft. The connecting element 309 may be connected to the inner side of the outer shaft 305 and may be locked in the lumen of the outer shaft 305 by a proximal portion of the connecting element 309, which may be compressed in diameter and thus radially pressed against the inner side of the outer shaft 305 at its proximal side. Thereby, a temporary connection of the connecting element 309 and the outer shaft 305 may be facilitated.
The diameter of the connecting element 309 may generally be provided with a diameter that may allow the connecting element 309 to be inserted into the outer shaft 305 relative to the proximal portion of the connecting element 309. For example, if the rolling membrane 301 is provided as a 4Fr element and if the outer shaft is a 6Fr element, the proximal portion of the connecting element 309 may be provided with a Fr of 6Fr or less to form a seal between the outer shaft 305 and the connecting element 309.
Preferably, the outer shaft 305 may be provided with an inner diameter that is 1Fr larger than the diameter of the rolling membrane 301 to facilitate application of the parent-child technique (e.g., a smaller catheter may be inserted into the interior volume of a larger catheter). In a most preferred embodiment, the outer shaft 305 may be provided as a 6Fr component and the connecting element may be provided as a 4Fr component.
As shown in fig. 3A and 3B, by inserting the connecting element 309 into the outer shaft 305, a rolling membrane guide extension catheter (RMGCE) may be formed by a member of medical personnel. In a preferred embodiment RMGCE may be formed from any guide catheter that serves as the outer shaft 305.
Fig. 4 depicts another exemplary embodiment of a catheter 400, particularly a rolling film catheter, which may include an inner shaft (not shown) with additional tension locks for forming a rolling film guide extension catheter (RMGCE), RMGCE to be inserted into a guide catheter with the correct inner diameter. The catheter 400 may comprise a rolling membrane 401 extending axially from the distal direction D to the proximal direction P.
At the proximal end of the rolling membrane 401 (as seen in case the rolling membrane 400 is fully rolled out), the rolling membrane 401 may be connected to a sealing and/or connecting element 409. The sealing element 409 may include a hydrophilic coating and/or an expandable coating. The sealing element 409 may preferably comprise a sealing element. The sealing element may be provided as a spring sealing element.
Rolling membrane 401 may pass through valve 411, such as a Tuohy borst adapter. The valve 411 may preferably be placed outside the patient. The valve 411 may be provided with means 414 for providing a fluid (e.g. liquid and/or gas) to the expandable volume of the rolling membrane 401.
Catheter 400 may also include a steering element 412 disposed in lumen 404 of rolling membrane 401. The steering element 412 may be connected to the sealing element 409 and may extend or be operably coupled to a location outside the patient. The handling element 412 may be adapted to avoid that the sealing element 409 (and the rolling membrane 401) unintentionally enters the blood vessel of the patient too great a distance (in particular, if the rolling membrane 401 is inflated, the hydraulic pressure applied to the rolling membrane 401 pulls the sealing element 409 out of the guiding catheter). The manipulation member 412 may allow for placement of the sealing member 409 within, for example, an outer shaft (not shown).
Fig. 5 exemplarily shows that a rolling membrane 501 (e.g., rolling membrane 401 described above with reference to fig. 4) is inserted into an outer shaft 505 (e.g., a guide catheter, so as to form RMGCE) in five stages i) -v).
Stage i) shows a rolling membrane 501, which may be configured as described above with reference to fig. 4.
Stage ii) shows the insertion of rolling diaphragm 501 into outer shaft 505. The maximum radius of the rolling membrane 501 may be configured to be smaller than the inner diameter of the outer shaft 505.
Stage iii) shows a scenario where the rolling diaphragm 501 is inserted into the outer shaft 505. The connecting and/or sealing element 509 (preferably provided with a hydrophilic and expandable coating) may have been exposed to a liquid such that sealing of the inner lumen of the outer shaft 505 may be exhibited. The seal may cause a preferably airtight separation of the distal volume portion of the lumen of the outer shaft 505 from the proximal volume portion of the lumen of the outer shaft 505. It may releasably connect the rolling membrane 501 to the outer shaft 505 (e.g., a proximal portion of the rolling membrane).
Stage iii) further depicts the blocking element 513, which may comprise a volume element configured to have a size exceeding the diameter of the outer shaft 505 such that the blocking element may not be able to enter the outer shaft 505, e.g., from the proximal direction P. This configuration may ensure that the steering element 512 does not accidentally enter the patient's blood vessel.
Stage iii) further depicts rolling film 501 in an at least partially rolled-out state.
Stage iv) depicts the rolling membrane 501 of stage iii) wherein the medical device 514 has been inserted into the lumen 504 of the rolling membrane 501. The medical device 514 may be, for example, a catheter, which may be inserted from the proximal direction P into the distal direction D through the lumen of the rolling membrane 501.
Stage v) depicts the rolling membrane 501 of stage iv) wherein the medical device 514 has been delivered to a location distal to the distal-most tip of the rolling membrane 501.
In general, the rolling membrane 501 may preferably evert into a narrow, tortuous vessel. Upon everting the rolling membrane 501 into the blood vessel (as shown in stage iii), the rolling membrane 501 may at least partially collapse (stage iv) and any catheter less than 4Fr may be pushed toward the target location.
Fig. 6A and 6B schematically illustrate a catheter 600 as described above with reference to fig. 4 and 5.
Fig. 6A shows a possible combination of rolling membrane 601 with outer shaft 605 (e.g., outer shaft 505 as described above with reference to fig. 5) and valve 611 (e.g., valve 411 as described above with reference to fig. 4). In fig. 6A, the rolling membrane 601 has been at least partially inserted into the outer shaft 605. The outer shaft 605 may be movable in a proximal direction P, wherein the connecting element 609 may further enter the outer shaft 605 in a distal direction due to translation of the outer shaft 605. The sliding movement of the connecting element 609 may advantageously be supported by a preferably hydrophilic coating of the connecting element 609, which may reduce friction during sliding translation.
Fig. 6B shows the catheter of fig. 6A, wherein the outer shaft 605 of fig. 6A has been contacted with the valve 611 by further moving the outer shaft 605 in the proximal direction, thereby forming RMGCE.
Fig. 6B also shows the rolling membrane 601 in an at least partially everted state.
In a preferred embodiment, rolling membrane 601 may comprise a diameter that is less than the diameter of a patient's blood vessel. Further, the diameter of the rolling membrane 601 may be larger than the inner diameter of the outer shaft 605 (at least in the rolled-out state of the rolling membrane 601).
In some embodiments, the rolling membrane 601 may be connected to a proximal shaft in a proximal portion of the rolling membrane 601.
Connecting element 609 may also be adapted to seal catheter 600 in the distal portion of catheter 600.
To connect the outer shaft 605 to the valve 611, the valve 611 may include a shaft-shaped portion oriented in the distal direction D and including an outer diameter having a diameter slightly smaller than an inner diameter of the outer shaft 605. The shaft-shaped portion may be provided with an inner diameter of at least 4 Fr.
In some exemplary embodiments, catheter 600 may be provided with an additional tube inside the lumen of rolling membrane 601 as an additional steering element 612 for steering connecting element 609. Valve 611 may be configured to be pressure-tight and may be adapted to seal against a proximal portion of catheter 600.
The volume element 613 may be similar to the volume element 513 outlined with reference to fig. 5.