cardiac assist devices

Abstract

A cardiac assist device (1) includes a cup element (2), an inner balloon element (5), and a tube element (6). The cup element (2) has a cup wall (2a), one or more inflow openings (3), and an outflow element (4) having an opening (4a). The inner balloon element (5) is positioned inside the cup element (2) and is free from the outflow element (4). The tube element (6) is arranged to inflate and deflate the inner balloon element (5) during operation. During operation in a pumping mode of operation, the combination of the first material, the dimensions of the cup wall (2a), and the dimensions of the outflow element (4) provides a containment force by the cup element (2) that counteracts an outwardly directed force of the inner balloon element (5).

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates to a cardiac assist device comprising a cup element, an inner balloon element, and a tube element. [Background technology]

[0002] (Background technology) U.S. Patent Publication No. US-B-5,169,378 describes an intraventricular assist pump. The pump comprises a body pump or outer chamber with a double-lumen wall that is inflatable and variable stiffness, i.e., an expandable but static outer cup. In operation, the (inflatable) outer chamber is rigid and static during operation. A valve orifice section or flexible constriction of the pump is provided that conforms to the "open" or "closed" state or position of the aortic or pulmonary valve, avoiding the need for a valve to pump blood from the pump. An inner balloon with a gradual wall thickness is provided, causing a sequential rhythm of inflation and deflation.

[0003] International Patent Publication No. WO 2015 / 131879 (Patent Document 2) discloses a catheter device for conducting fluids, particularly bodily fluids, in a directed manner. The catheter device is described as being positioned within the aorta and includes an outer shell having an interior and a frame, the outer shell having at least three openings and designed as a fluid line in the area between the first opening and the second opening, and an anti-reflux valve arranged in the second opening. During operation, the outer shell is in an expanded state and is completely rigid (e.g., implemented as a stent). The anti-reflux valve includes a valve film that is at least partially fastened to the outer shell so that the second opening can be completely covered by the valve film.

[0004] International Patent Application No. WO2020 / 022905 (Patent Document 3) discloses a cardiac support device for circulatory assistance, which has a chamber body with a first opening. A dynamic volume body is provided to increase and decrease the internal volume of the chamber body. Blood outflow during operation is directed using a directional flow structure. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Patent No. 5,169,378 [Patent Document 2] International Publication No. 2015 / 131879 [Patent Document 3] International Publication No. 2020 / 022905 Summary of the Invention [Means for solving the problem]

[0006] (Summary of the Invention) The present invention seeks to provide an improved cardiac assist device that allows for proper and efficient operation.

[0007] According to the present invention, there is provided a cardiac assist device as defined above, comprising: a cup element having a cup wall comprising a first material and defining an internal cup volume; one or more inflow openings arranged in the cup wall to allow a first fluid (such as blood) to flow into the cup element during operation; and an outflow element fluidly connected to the cup wall and having an opening for discharging the first fluid during operation. An inner balloon element is present, having a balloon wall comprising a second material and defining an internal balloon volume, and the inner balloon element is positioned inside the cup element, the inner balloon element being separated from the outflow element. A tube element is provided in fluid communication with the inner balloon element to inflate and deflate the inner balloon element during operation, creating a pumping mode of operation and a filling mode of operation, respectively. During operation in the pumping mode of operation, the combination of the first material, the dimensions of the cup wall, and the dimensions of the outflow element provides a containment force by the cup element that counteracts an outwardly directed force of the inner balloon element.

[0008] Embodiments of the present invention allow for very good and efficient operation of a cardiac assist device with a very limited number of components. [Brief explanation of the drawings]

[0009] The invention will be discussed in more detail below with reference to the accompanying drawings.

[0010] [Figure 1] 1A and 1B show cross-sectional views of a first embodiment of the present invention.

[0011] [Figure 2] 2A-2D show cross-sectional views of a second embodiment of the present invention.

[0012] [Figure 3] FIG. 3A shows a perspective view of a third embodiment of the present invention, and FIG. 3B shows a cross-sectional view of an alternative embodiment of the skeletal structure to the embodiment shown in FIG. 3A. [Figure 4]FIG. 4 shows a side view of a further embodiment of a cardiac assist device according to the present invention. [Figure 5] FIG. 5 shows a cross-sectional view taken along line VV in FIG. [Figure 6] FIG. 6 shows a cross-sectional view taken along line VI-VI in FIG. [Figure 7] 7A and 7B show cross-sectional views along line VII-VII in FIG. 4 in two operating states. [Figure 8] 8A-C show perspective views (partially) of still further embodiments of the present invention. [Figure 9] FIG. 9 shows an exploded perspective view of a one-way valve used in a further embodiment of the present invention. [Figure 10] FIG. 10 shows a side view of yet a further embodiment of a cardiac assist device in accordance with the present invention. [Figure 11] FIG. 11 shows a perspective view of an embodiment of a cardiac assist device, with details regarding the retrieval element.

[0013] [Figure 12] FIG. 12 shows a cross-sectional view of an embodiment of a cardiac assist device of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] (Description of the embodiment) The present invention seeks to provide an intraluminal cardiac assist device that more closely approximates the heart's natural function. The resulting cardiac assist device, according to embodiments of the present invention, can function to provide circulatory assistance in a patient by pumping blood from a cardiovascular lumen (e.g., the left ventricular cavity) with a sufficiently high stroke volume and efficient placement.

[0015] In an embodiment of the present invention, two pump mechanisms are implemented that work together to make the function of the cardiac assist device more efficient.

[0016] 1A and 1B show two cross-sectional views of a first embodiment of a cardiac assist device 1 of the present invention, where Fig. 1A shows the cardiac assist device 1 at the start of a pumping mode of operation and Fig. 1B shows the cardiac assist device 1 at the start of a filling mode of operation, the two operating modes alternating. The cardiac assist device 1 has, for example, a generally elliptical or oval outer shape with a longitudinal axis of symmetry.

[0017] The cardiac assist device 1 comprises a cup element 2 and an inner balloon element 5, which inflates during a pumping mode of operation and deflates during a filling mode of operation. The inner balloon element 5 has a balloon wall 5a, and the cup element 2 has a cup wall 2a, which has an inflow opening 3, allowing a first fluid (blood) to enter the space between the cup wall 2a and the balloon wall 5a. The cup element 2 further comprises an outflow element 4, which is fluidly connected to the cup wall 2a and has an opening 4a for discharging the first fluid during operation. A tube element 6 is in fluid communication with the inner balloon element 5 and serves to inflate and deflate the inner balloon element 5 during operation, creating the pumping and filling modes of operation, respectively. As shown in FIG. 1A, the cup element 2 has an inner cup volume Vc1, which is substantially the same during the pumping and filling modes of operation. The inner balloon element has an initial inner volume Vb1 at the start of the pumping mode of operation, as shown in Figure 1A, and an expanded inner volume Vb2 at the start of the filling mode of operation, as shown in Figure 1B. The obtainable stroke volume SV of the cardiac assist device 1 of this embodiment is therefore Vb2-Vb1.

[0018] To obtain this pumping and filling mode of operation, one or more inlet openings 3 need to be blocked during the pumping mode of operation and open during the filling mode of operation, which can be achieved as explained below or by a further group of embodiments, where one or more inlet openings 3 are equipped with a one-way valve.

[0019] Furthermore, in one group of embodiments, the outflow element 4 has a tube-like structure. The tube-like structure can be sized long enough to extend through the aortic valve when the cardiac assist device 1 is positioned in the left ventricle (e.g., having a length of at least 20 mm) and ensure that the opening 4 a is present in the aorta during operation. Additionally or alternatively, the outflow element 4 is a directional flow element. This allows for obtaining a directed flow of the first fluid during a pumping mode of operation, e.g., directed toward the aortic valve during operation.

[0020] The cardiac assist device 1 of the present invention indeed combines two pumping mechanisms in order to obtain the smallest possible external volume of the cardiac assist device 1 with the highest possible stroke volume and with the least possible obstruction of the outflow of the first fluid through the outflow element 4. This is made possible by a (dynamic) balance of forces during the alternating pumping and filling operating modes.

[0021] More specifically, during operation in the pumping mode of operation, the combination of the first material of the cup wall 2a, the dimensions of the cup wall 2a, and the dimensions of the outflow element 4 provide a containment force by the cup element 2 that counteracts the outwardly directed force of the inflated inner balloon element 5. These structural features of the cup wall 2a (first material properties, dimensions (thickness, radius, surface area) of the cup wall 2a, and dimensions of the outflow element 4 (area of ​​the openings 4a, diameter and / or length of the outflow element 4) determine the containment force. It should be noted that additional parameters such as the rate of volume change of the stroke volume, the resistance across the outflow element 4, the viscosity of the first fluid, and / or back pressure from the environment outside the cardiac assist device (such as aortic pressure in the case of use of a ventricular assist type cardiac assist device 1) may be relevant during operation. However, these may be taken into consideration when setting the structural features of the cup element 2.

[0022] Furthermore, during the filling mode of operation, the structure and materials of the cup element 2 ensure that the shape of the cup wall 2a remains substantially the same (i.e., with the inner cup volume Vc1) to counteract the force generated by the deflating inner balloon element 5. It should be noted that additional parameters in this case may be relevant during operation, such as the resistance across the total inlet surface area of ​​the inlet openings 3 in the cup wall 2a, the speed of deflating the inner balloon element 5, and the viscosity of the first fluid. Again, these additional parameters may be taken into consideration when selecting the structural features of the cup element 2 for the overall design of the cardiac assist device 1.

[0023] Thus, in general terms, the present invention provides a cardiac assist device 1 comprising a cup element 2 having a cup wall 2a comprising a first material and defining an inner cup volume Vc1, one or more inflow openings 3 arranged in the cup wall 2a to allow a first fluid to enter the cup element 2 during operation, and an outflow element 4 connected in fluid communication with the cup wall 2a and having an opening 4a for discharging the first fluid during operation. There is an inner balloon element 5 comprising a second material and having a balloon wall 5a defining inner balloon volumes Vb1, Vb2, positioned inside the cup element 2 and separate from the outflow element 4, and a tube element 6 in fluid communication with the inner balloon element 5 for inflating and deflating the inner balloon element 5 during operation to create a pumping mode and a filling mode of operation, respectively. During operation in the pumping mode of operation, the combination of the first material, the dimensions of the cup wall 2a, and the dimensions of the outflow element 4 provides a containment force by the cup element 2 that counteracts the outwardly directed force of the inner balloon element 5.

[0024] In one group of embodiments, during the pumping and filling modes of operation, the cup element 2 has a substantially constant inner cup volume Vc1.

[0025] 1A and 1B, the cup element 2 further comprises a skeletal (or reinforcing) structure 7b, for example as an integral part of the cup wall 2a, to provide rigidity to the cup wall 2a. In other words, in a further embodiment, the cup element 2 comprises skeletal structures 7a, 7b that are integrated with the cup wall 2a.

[0026] In a further group of embodiments, the cup element 2 has a dynamic inner cup volume Vc1-Vc2, as shown in the exemplary embodiment shown in cross section in Figures 2A-2D. The cup wall 2a will cooperate synchronously with the inflating / deflating balloon element 5 during operation to obtain an even more effective stroke volume SV. In turn, Figures 2A-2D show that there are two main actions within the cardiac assist device 1: in Figure 2A, the cup element 2 remains fully open (i.e., at a maximum inner cup volume Vc1) until the inner balloon element 5 is fully deflated and the inner volume is filled with a first fluid via one or more inflow openings 3. Figure 2B then shows the next step in the sequence, where the cup wall 2a is reduced (or tightened) to a minimum inner cup volume Vc2 and the inner balloon element 5 is inflated from an inner balloon volume Vb1 to Vb2, thereby combining the two forces Fc and Fb for the pumping mode of operation. Subsequently, the inner balloon element 5 is again allowed to deflate, again filling the inner volume of the cardiac assist device 1 with the first fluid (filling operating mode), which continues again with an increase in the inner cup volume to its maximum level Vc1 (FIG. 2D). A new cycle can then begin again.

[0027] In one group of embodiments, the varying dynamic volume of the cup element 2 is achieved by appropriate selection of the structural features of the cup element 2, such as selection of the first material, the dimensions of the cup wall 2a, and the dimensions of the outflow element 4.

[0028] In a further group of embodiments, this dynamic volume of the cup element 2 is obtained by having flexible skeletal structures 7a, 7b arranged to control the cup volume during operation. It should be noted that the skeletal structure 7b shown in the exemplary embodiment of Figures 1A and 1B can also be applied to the exemplary embodiment shown in Figures 2A-2D.

[0029] In further embodiments, the flexible skeletal structures 7a, 7b comprise hollow channels that can be expanded and contracted, for example, to obtain varying inner cup volumes Vc1-Vc2. To this end, the hollow channels are in fluid communication with the tubing elements 6. Alternatively, the cardiac assist device 1 further comprises a secondary tubing element in communication with the hollow channels. All of these components enable operation of the cardiac assist device 1 according to these embodiments using relatively high pressures, for example, 0.5 to 20 bar. This is higher than prior art systems (see, for example, U.S. Patent Publication No. US-B-5,169,378), which operate using inflation pressures of 0.5 to 1 bar, potentially resulting in faster and more robust operation of the cardiac assist device 1.

[0030] In a further group of embodiments, the skeletal structures 7a, 7b comprise a shape-memory material to obtain a containment force that counteracts the inflation force of the inner balloon. The shape-memory material may, for example, be in the form of a wire and include Nitinol as the memory material. For example, the skeletal structure 7b may be implemented as a helical wire that is in turn contained within the cup wall 2a, as shown in the embodiment of Figures 1A and 1B.

[0031] FIG. 3A shows a perspective view of yet another embodiment of the cardiac assist device 1 of the present invention. In this embodiment, the skeletal structure 7b comprises a spiral wire element integrated with the cup wall 2a. FIG. 3B shows a cross-sectional view of a further embodiment, in which the skeletal structure 7a, 7b comprises a spine element 7a and multiple rib elements 7b arranged along the longitudinal direction of the cardiac assist device 1, each attached to the spine element 7a on one side. The rib elements 7b extend, for example, in a generally perpendicular manner from the spine element 7a to form a thoracic cage-type skeletal structure. An added advantage of this embodiment is that the rib elements 7b are easily folded, allowing for easier entry and exit of the cardiac assist device (e.g., into the left ventricle via a vascular catheter) before operation. In yet another alternative embodiment, the spine element 7a and / or the rib elements 7b may be partially solid (e.g., nitinol) and partially open (e.g., hollow polyurethane material).

[0032] In yet a further group of embodiments, the cardiac assist device further comprises a control unit 10 arranged to control the fluid flow of the second fluid through the tube element 6 during operation. This is capable of periodically inflating / deflating the inner balloon element 5 to obtain the pumping and filling operation modes described above. The second fluid can be (compressed) air, gas, liquid, water, etc. The tube element 6 is implemented, for example, as a catheter (capable of carrying the second fluid), allowing the use of remote control of the inflation / deflation of the inner balloon element 5 by a remote pressure source. If present, the hollow channels of the above-described skeletal structures 7a, 7b can also be controlled in this manner. For example, when using high-pressure fluid, the hollow channels eventually become rigid, providing shape consistency for the cup element 2. By adding resistance elements and selecting the dimensions of the inner volume of the hollow channels versus the inner balloon 5, the same second fluid source and control unit 10 can be used to first inflate the skeletal structures 7a, 7b and subsequently the inner balloon element 5.

[0033] In a still further embodiment, the cup element 2 comprises an expandable skeleton structure 7a, 7b, the internal volume of which is smaller than the (possible) internal volume of the inner balloon element 5, e.g., 1 cc versus 20 cc. This allows the expandable skeleton 7a, 7b and the inner balloon element 5 to be connected to a single (remote) pressure source via the tubing element 6, as the smaller volume will ensure inflation of the skeleton structure first, followed by inflation of the inner balloon element 5. In a further embodiment, to implement the operational use of an embodiment of the invention with a dynamic inner cup volume, the control unit 10 is arranged to independently control the inner cup volumes Vc1, Vc2 and the inner balloon volumes Vb1, Vb2.

[0034] The control unit 10 may be configured to apply specific synchronized timing between inflating / deflating the cup element 2 and inflating / deflating the inner balloon element 5. The cup element 2 may change its inner cup volume from Vc1 to Vc2 immediately before, simultaneously with, or immediately after the change in inner balloon volume from Vb1 to Vb2. In specific embodiments, the maximum inner cup volume Vc1 may be timed prior to (just before) the inflation of the inner balloon element 5, thus ensuring optimal stroke volume.

[0035] Furthermore, in still further exemplary embodiments, the frequency of pumping may be set by the control unit 10 to obtain optimal performance. This frequency of pumping may be controlled in synchronization with the actual (sensed) heart rate. Still further, the frequency of pumping may be higher, for example, 2 to 10 times higher than the actual heart rate, to obtain a higher flow of the first fluid.

[0036] In a further embodiment, as shown in the exemplary embodiment of Figure 3, the pipe element 6 is provided in contact with the outflow element 4 along a predetermined length thereof. This off-center positioning of the pipe element 6 allows for generally unobstructed flow of the first fluid into the outflow element 4 and out through the openings 4a.

[0037] In a further embodiment, the combination of the cup element 2 and the inner balloon element 5 is adjustable in delivery mode, with the maximum diameter of the combination being less than 7 mm, e.g., less than 5 mm. This allows, for example, a cardiac assist device to be delivered to the left ventricle via the aorta and a conventional catheter system in a reliable and safe manner. The combination is, for example, elongated in delivery mode and elliptical in operating mode.

[0038] 3A, the tube element 6 is a multi-lumen (e.g., dual-lumen) catheter. One of the lumens 6a is used, for example, for inflation / deflation of the inner balloon element 5, and the additional lumen 6b provides space for a guide wire 8 extending further along or from the cardiac assist device 1, for example, for proper positioning of the cardiac assist device 1 within the left ventricle.

[0039] In a further alternative embodiment, the inner balloon element 5 comprises a multi-stage balloon assembly having at least two balloon parts with different stiffness materials. The multi-stage balloon assembly may, for example, be a shaped balloon or with controlled volume expansion (or directional thrust). Furthermore, the shaped balloon 5 may be positioned relative to the outflow element 4 so that directional expansion occurs from the apex of the cup element 2 toward the outflow element 4. Alternatively, or in addition, the shaped balloon 5 may be sized and positioned to block the inflow opening 3 during the initial stages of inflation, thereby creating a one-way valve assembly. In other words, one of the two balloon parts is positioned to block one or more inflow openings 3 during the pumping mode of operation.

[0040] FIG. 4 shows a side view of yet another embodiment of a cardiac assist device 1 according to the present invention, having a cup element 2 and an outflow element 4 similar to the embodiments described above. In this exemplary embodiment, the skeletal structure 7b is provided as a wire mesh structure, e.g., using nitinol or another shape-memory material. As an example, the skeletal structure 7b is manufactured similarly to a laser-cut stent. In this embodiment, the skeletal structure 7b allows the diameter of the cardiac assist device 1 to decrease when it is stretched along its longitudinal axis (see also the description with reference to FIGS. 10 and 11 ). Once positioned within the heart, the shape of the cup element 2 returns to its intended shape, and the wire mesh structure ensures the shape of the cup element 2, which has an internal volume Vc1. During operation (both expansion and contraction), the skeletal structure 7b in this embodiment provides radial rigidity that maintains the internal volume Vc1. At the end of the cup element 2, the skeletal structure 7b and further local components of the cardiac assist device 1 are held together and protected by an end cap 19, which is, for example, shaped or rounded to provide as little damage as possible to the (cardiac) tissue during use of the cardiac assist device 1.

[0041] To prevent excessive stretching of the outer surface of the cup element 2 during operation, the skeletal structure 7b has a wire mesh structure and is provided with one or more circumferential restraining elements 11. The restraining elements 11 are, for example, made from a non-compliant material and ensure a local maximum radius of the cup element 2.

[0042] Figure 5 shows a cross-section along line VV in Figure 4, and Figure 6 shows a cross-section along line VI-VI in Figure 4. In one group of embodiments, cup wall 2a comprises inner layer 12 and / or outer layer 13. Inner and / or outer layers 12, 13 can be made of a compliant, high-extension material or a non-compliant material (or a combination of compliant and non-compliant materials). Furthermore, outer layer 13, which spans across wire mesh skeletal structure 7b (and restraining element 11), also provides a smoother outer surface, thereby minimizing interference with cardiac tissue (during insertion and operation).

[0043] 4-6, the cup element 2 further comprises a transvalvular section 14, which is in communication with the outflow element 4. In use, this section (through which the skeletal structure 7b extends) can be positioned, for example, at the level of the aortic valve, to provide a permanently open passageway from the inner volume Vc1 of the cup element 2 to the outflow element 4.

[0044] 7A and 7B show cross-sectional views along line VII-VII in FIG. 4 in two operating states, illustrating the operation of the outflow element 4, which includes a collapsible tubular element 15. The collapsible tubular element 15 is made of a material that provides radial rigidity (the collapsible tubular element 15 has a maximum diameter even when fluid is pumped therethrough at high pressures and / or velocities) and sufficient flexibility to allow the collapsible tubular element 15 to be collapsed to act as a one-way valve. The open position of the collapsible tubular element 15 is shown in FIG. 7A, and the closed position is shown in FIG. 7B. The collapsible tubular element 15 has a length of, for example, 0.5 to 4 cm, e.g., 2 cm, and a diameter of, for example, 5 to 15 mm, e.g., 12 mm. The collapsible tubular element 15 is made of a flexible material, such as, for example, Tecotane 85.

[0045] In the exemplary embodiment shown, the outflow element 4 comprises an outflow skeletal structure 7c formed by expansion of the skeletal structure 7b. This provides partial support for the outflow element 4 and is compatible with the intended function of the collapsible tubular element 15 and the intended retrieval mechanism function. Additionally or alternatively, the collapsible tubular element 15 is at least partially fixed to the outflow skeletal structure 7c. Additionally or alternatively, the collapsible tubular element 15 may comprise an outer end formed to still further improve one-way valve function, for example, by providing angulation of the upper end of the collapsible tubular element 15 (e.g., at 40 degrees in the longitudinal direction of the cardiac assist device 1).

[0046] This exemplary embodiment of the cardiac assist device 1 has a rigid part (cup element 2) positioned in the ventricle during operation, a transvalvular section 14 that passes through the aortic valve during operation, and a one-way valve mechanism formed by the collapsible tubular element 15 of the outflow element 4. During systole, the rigid part converts energy provided by the action of the inner balloon element 5 and pushes the fluid towards the outflow element 4. Already at the end of this phase, as the fluid flow decreases and the ejection ends, the collapsible tubular element 15 starts to close, causing the pressure inside the collapsible tubular element 15 to be lower than the ambient pressure. During diastole, the outflow framework 7c prevents the outflow element 4 from collapsing, and the collapsible tubular element 15 remains closed, thus preventing a possible backflow of fluid.

[0047] 4, 7A, and 7B, an attachment element 16 is provided at the upper end of the skeletal structure 7b (or even just the upper end of the outflow skeletal structure 7c), which is useful in use when retrieving the cardiac assist device 1. FIG. 10 shows a side view of parts of yet a further embodiment of a cardiac assist device 1 according to the present invention, which plays a role in positioning and retrieving the cardiac assist device. A wire 16a can be attached to the attachment element 16 of the skeletal structure 7b / outflow skeletal structure 7c. This attachment to the tip of the outflow element 4 allows tension to be applied on the cup element 2 while it retracts, stretching the cup element 2 and reducing its width.

[0048] 11 shows a perspective view of an embodiment of cardiac assist device 1, with details regarding the retrieval elements. In this perspective view, inner balloon element 5 and tube element 6 are also shown, as well as guidewire 8 and outer shaft 18 (forming part of a catheter used to position and retract cardiac assist device 1).

[0049] The tapered shape of the outflow element 4 (more specifically, the outflow skeletal structure 7c) allows the cardiac assist device 1 to be retracted into the outer shaft 18. The tube element 6 acts as a fastener for the end cap 19 (which is also attached to the inner balloon element 5) and can allow sufficient force to be applied to stretch the cardiac assist device 1 to reduce its diameter so as to (again) fit into the outer shaft 18.

[0050] 8A-C show perspective views (of a portion) of still further embodiments of the invention relating to the inflow openings 3 of the cardiac assist device 1, and FIG. 9 shows an exploded perspective view of an implementation of one-way valves 12, 17 used in further embodiments of the invention. In these embodiments, one or more of the inflow openings 3 are provided with one-way valves 17.

[0051] Figure 8A shows the cup wall 2a of the cup element 2, which is provided with a row of inlet openings 3 (given as thick lines), and Figure 8B shows the leaf-like element 17 cooperating with the outer surface 2a to act as a one-way injection valve. In Figure 8C the mutual positioning is shown, with the leaf-like element 17 attached to the inner surface of the cup wall 2a along the dotted lines, thereby creating a cooperating area in the region below the row of inlet openings 3.

[0052] FIG. 9 shows an exploded view of a simplified embodiment of a one-way inlet valve implementation. The cup wall 2a is formed by a skeletal structure 7b (partially shown), an inner layer 12 (with an inlet opening 3), and leaf-like elements 17. The leaf-like elements 17 are positioned to allow for closure of the inlet opening 3. The resulting bonded area has dimensions of, for example, 0.5 to 4 mm, e.g., 2.5 mm, allowing for sufficiently rapid opening and closing of the formed one-way inlet valve. The inlet opening 3 has a diameter of at least 2 mm, e.g., 3.5 mm. The bonded area also provides directional inflow of fluid into the inside of the cup element 2, helping the spiral flow to close the one-way inlet valve in a sufficiently rapid manner. Multiple such one-way inlet valve lines can be provided in parallel along the longitudinal direction of the cup wall 2a, with the added benefit of increasing the directional and spiral flow inside the cup element 2. The inlet openings 3 may also have an orientation in the same direction to obtain an even more directed inflow of fluid. In this manner, the fluid flow over the leaf-like elements 17 helps to close them faster.

[0053] 12 shows a cross-sectional view of an embodiment of the cardiac assist device of the present invention, illustrating a further embodiment of the inside of the inner balloon element 5. In this embodiment, during operation, the inner balloon volume Vb2 is smaller than the inner cup volume Vc1. During inflation, this will ensure that the inner balloon element 5 does not trap or encapsulate any fluid between the inner balloon element 5 and the inner surface of the cup element 2. During deflation, fluid will be present between the inner balloon element 5 and the inner surface of the cup element 2, preventing a "vacuum" in the area between the two surfaces and their possible sticking.

[0054] In the exemplary embodiment shown, the inner balloon element 5 is positioned distally within the cup element 2, i.e., closer to the end cap 19 than the outflow element 4. This will prevent an increase in outflow resistance created by the inner balloon element 5 itself.

[0055] Additionally or alternatively, the inner balloon element 5 may have a conical shape, which causes a predetermined flow of fluid towards the outflow element 4.

[0056] Using one or more of the features described above with reference to Figure 12 or the previous figures, it is possible to inflate the inner balloon element 5 in two phases, for example, using variable compliance of the material of the inner balloon element 5, using a specific shape (e.g., a cone), or using a combination thereof.

[0057] In the above described embodiment, a tube element 6 is used in communication with the inner balloon element 5. A fluid (air or helium) may be used to inflate and deflate the inner balloon element 5. In order to obtain a sufficiently high frequency and timing control of the inflation / deflation action, the tube element 6 may be equipped with specific technical features. For example, in order to keep the flow resistance sufficiently low, a thickness of 4 to 8 mm of the tube element 6 may be used. 2 , e.g., 5.3 mm 2 An inner diameter of 100 to 150 cm (for example, 110 cm) is advantageous. 2 This may be combined with an optimized expansion area of ​​the inner balloon element 5. Furthermore, the material of the tube element 6 may be selected to simultaneously obtain a sufficiently high radial stiffness (e.g., to allow high speed helium flow in both directions) and a sufficiently high longitudinal push / pull strength to allow placement, positioning, and retrieval of the cardiac assist device 1.

[0058] The present invention has been described above with reference to several exemplary embodiments, as shown in the drawings. Modifications and alternative implementations of several parts or elements are possible and fall within the scope of protection, as defined in the appended claims.

[0059] (Item 1) A cardiac assist device (1), comprising: A cup element (2), a cup wall (2a) comprising a first material and defining an interior cup volume (Vc1); one or more inlet openings (3) arranged in the cup wall (2a) to allow a first fluid to enter the cup element (2) during operation; an outflow element (4) connected in fluid communication with the cup wall (2a) and having an opening (4a) for discharging the first fluid during operation; a cup element (2) having an inner balloon element (5) having a balloon wall (5a) comprising a second material and defining an inner balloon volume (Vb1, Vb2), the inner balloon element (5) being positioned inside the cup element (2) and separated from the outflow element (4); a tube element (6) in fluid communication with the inner balloon element (5) for inflating and deflating the inner balloon element (5) during operation to create a pumping mode of operation and a filling mode of operation, respectively; Equipped with During operation in the pumping mode of operation, the combination of the first material, the dimensions of the cup wall (2a), and the dimensions of the outflow element (4) provides a containment force by the cup element (2) that counteracts the outwardly directed force of the inner balloon element (5). (Item 2) 2. The cardiac assist device according to item 1, wherein the cup element (2) has a substantially constant inner cup volume (Vc1) during the pumping and filling modes of operation. (Item 3) 3. The cardiac assist device according to item 1 or 2, wherein the cup element (2) comprises a skeletal structure (7a, 7b) integrated with the cup wall (2a). (Item 4) 4. A cardiac assist device according to any one of items 1-3, wherein the skeletal structure (7a, 7b) has a wire mesh structure and is provided with one or more circumferential restraining elements (11). (Item 5) 5. The cardiac assist device according to any one of items 1-4, wherein the cup wall (2a) comprises an inner layer (12) and / or an outer layer (13). (Item 6) 6. The cardiac assist device according to any one of items 1-5, wherein the cup element (2) further comprises a transvalvular section (14) in communication with the outflow element (4). (Item 7) 7. The cardiac assist device according to any one of items 1-6, wherein the outflow element (4) comprises a collapsible tubular element (15). (Item 8) 8. A cardiac assist device according to any one of items 3-7, wherein the skeletal structure (7a, 7b) comprises a shape memory material. (Item 9) 9. The cardiac assist device according to any one of items 3-8, wherein the outflow element (4) comprises an outflow skeletal structure (7c) formed by an extension of the skeletal structures (7a, 7b). (Item 10) 10. A cardiac assist device according to any one of items 7-9, wherein the foldable tubular element (15) is at least partially fixed to the outflow framework (7c). (Item 11) 11. The cardiac assist device according to any one of items 1-10, further comprising a control unit (10) arranged to control fluid flow through said tubing elements (6) during operation. (Item 12) 12. The cardiac assist device according to any one of items 1-11, wherein the tube element (6) is provided in contact with the outflow element (4) along a predetermined length thereof. (Item 13) 13. The cardiac assist device according to any one of items 1-12, wherein the combination of the cup element (2) and the inner balloon element (5) is adjustable to a delivery mode in which the maximum diameter of the combination is less than 7 mm, e.g., less than 5 mm. (Item 14) Item 14. The cardiac assist device of item 13, wherein the combination is elongated in the transport mode and oval in the operating mode. (Item 15) 15. The cardiac assist device according to any one of items 1-14, wherein the tube element (6) is a multi-lumen catheter. (Item 16) 16. The cardiac assist device according to any one of items 1-15, wherein the inner balloon volume (Vb2) is smaller than the inner cup volume (Vc1) during operation. (Item 17) 17. The cardiac assist device according to any one of items 1-16, wherein the inner balloon element (5) is positioned distally within the cup element (2). (Item 18) 18. The cardiac assist device according to any one of items 1-17, wherein the inner balloon element (5) has a conical shape. (Item 19) 19. The cardiac assist device according to any one of items 1-18, wherein the inner balloon element (5) comprises a multi-stage balloon assembly having at least two balloon parts with different stiffness materials. (Item 20) 20. The cardiac assist device according to any one of items 1-19, wherein the one or more inflow openings (3) are provided with a one-way valve (17). (Item 21) 4. The cardiac assist device according to item 3, wherein the skeletal structures (7a, 7b) are flexible skeletal structures arranged to control the cup volume during operation. (Item 22) 22. The cardiac assist device according to item 21, wherein the flexible skeletal structure (7a, 7b) comprises a hollow channel. (Item 23) 23. The cardiac assist device according to item 22, wherein the hollow channel is in fluid communication with the tube element (6). (Item 24) 24. The cardiac assist device according to item 22 or 23, wherein the cardiac assist device (1) further comprises a secondary tube element communicating with the hollow channel. (Item 25) 12. The cardiac assist device according to item 11, wherein the control unit (10) is arranged to independently control the inner cup volume and the inner balloon volume. (Item 26) 20. The cardiac assist device according to item 19, wherein one of the two balloon parts is positioned to block the one or more inflow openings (3) in the pumping mode of operation.

Claims

1. 1. A cardiac assist device, comprising: the cardiac assist device comprises a cup element, an inner balloon element, and a tube element; The cup element is a cup wall comprising a first material, the cup wall defining an interior cup volume, the cup wall comprising a skeletal structure including a wire mesh structure, an inner layer spanning across an interior of the wire mesh structure, and an outer layer spanning an exterior of the wire mesh structure; one or more inlet openings for allowing a first fluid to enter the cup element during operation; an outflow element connected to the cup wall, the outflow element having an opening for discharging the first fluid during operation; and the inner balloon element has a balloon wall, the balloon wall comprising a second material and defining an inner balloon volume, the inner balloon element being positioned inside the cup element and separated from the outflow element; the tube element is connected to the inner balloon element, the tube element being for inflating and deflating the inner balloon element during operation to create a pumping mode of operation and a filling mode of operation, respectively; During operation in the pumping mode of operation, the combination of the first material and the dimensions of the cup wall and the dimensions of the outflow element provides a containment force by the cup element, which counteracts an outwardly directed force resulting from inflation of the inner balloon element.

2. The cardiac assist device of claim 1 , wherein the cup element has a substantially constant interior cup volume during the pumping and filling modes of operation.

3. The cardiac assist device of claim 1 or claim 2, wherein the skeletal structure is integral with the cup wall.

4. The cardiac assist device of any one of claims 1 to 3, wherein the cup element comprises one or more circumferential restraining elements.

5. The cardiac assist device of claim 1 , wherein the cup element further comprises a transvalvular section in communication with the outflow element.

6. The cardiac assist device according to any one of claims 1 to 5, wherein the outflow element comprises a collapsible tubular element.

7. The cardiac assist device according to any one of claims 1 to 6, wherein the skeletal structure comprises a shape memory material.

8. The cardiac assist device of any one of claims 1 to 7, wherein the outflow element comprises an outflow skeletal structure formed by an extension of the skeletal structure.

9. A cardiac assist device as described in any one of claims 1 to 5, wherein the outflow element comprises a foldable tubular element, the outflow element comprises an outflow skeletal structure formed by an extension of the skeletal structure, and the foldable tubular element is at least partially fixed to the outflow skeletal structure.

10. The cardiac assist device according to any one of claims 1 to 9, further comprising a control unit configured to control fluid flow through the tube elements during operation.

11. The cardiac assist device according to any one of claims 1 to 10, wherein the tube element is arranged to contact the outflow element along a predetermined length of the tube element.

12. 12. The cardiac assist device according to claim 1, wherein the combination of the cup element and the inner balloon element is adjustable to a delivery mode, in which the maximum diameter of the combination is less than 7 mm.

13. The cardiac assist device of claim 12 , wherein the combination is elongated in the delivery mode and oval in the operating mode.

14. The cardiac assist device according to any one of claims 1 to 13, wherein the tube element is a multi-lumen catheter.

15. The cardiac assist device of any one of claims 1 to 14, wherein the inner balloon volume is smaller than the inner cup volume during operation.

16. The cardiac assist device according to any one of claims 1 to 15, wherein the inner balloon element is positioned distally within the cup element.

17. The cardiac assist device according to any one of claims 1 to 16, wherein the inner balloon element has a conical shape.

18. The cardiac assist device of any one of claims 1 to 17, wherein the inner balloon element comprises a multi-stage balloon assembly having at least two balloon parts with different stiffness materials.

19. The cardiac assist device of any one of claims 1 to 18, wherein the one or more inflow openings comprise one-way valves.

20. The cardiac assist device of claim 1 , wherein the skeletal structure is a flexible skeletal structure configured to control the cup volume during operation.

21. The cardiac assist device of claim 20 , wherein the flexible skeletal structure comprises a plurality of hollow channels.

22. 22. The cardiac assist device of claim 21, wherein the plurality of hollow channels are in fluid communication with the tube element.

23. 23. The cardiac assist device of claim 21 or claim 22, further comprising a secondary tube element in communication with the plurality of hollow channels.

24. The cardiac assist device of claim 10 , wherein the control unit is configured to independently control the inner cup volume and the inner balloon volume.

25. 19. The cardiac assist device of claim 18, wherein one of the two balloon parts is positioned to block the one or more inflow openings in the pumping mode of operation.

26. 25. The cardiac assist device of claim 10, wherein the control unit is configured to inflate and deflate the inner balloon element at a pumping frequency.

27. 27. The cardiac assist device of claim 26, wherein the control unit is configured to set the frequency of the pumping in synchronization with a sensed heart rate.

28. 28. The cardiac assist device of claim 26 or claim 27, wherein the control unit is configured to set the frequency of pumping substantially higher than an actual heart rate.

29. 28. The cardiac assist device of claim 26 or claim 27, wherein the control unit is configured to set the pumping frequency at least twice as high as the actual heart rate.

30. 28. The cardiac assist device of claim 26 or claim 27, wherein the control unit is configured to set the pumping frequency at least 2 to 10 times higher than the actual heart rate.

31. 28. The cardiac assist device of claim 26 or claim 27, wherein the control unit is configured to set the pumping frequency 2 to 10 times higher than the actual heart rate.

32. The cardiac assist device according to any one of claims 1 to 31, wherein the inner balloon element is configured to be inflated and deflated at a pumping frequency substantially higher than an actual heart rate.

33. 33. The cardiac assist device of claim 32, wherein the pumping frequency is at least two times higher than the actual heart rate.

34. 33. The cardiac assist device of claim 32, wherein the pumping frequency is at least 2 to 10 times higher than the actual heart rate.

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