Implantable artificial heart

Abstract

An implantable total artificial heart is disclosed. The artificial heart includes a first delivery chamber, a second delivery chamber, and an actuator disposed between the first delivery chamber and the second delivery chamber. The actuator is configured to operate between a first operating state and a second operating state. Further, the artificial heart includes a plurality of first wires wound around the first delivery chamber and the actuator, and / or a plurality of second wires wound around the second delivery chamber and the actuator. Each of the plurality of first and second wires is configured to pressurize the first and second delivery chambers in response to the operation of the actuator for receiving fluid into the first and second delivery chambers and for discharging fluid from the first and second delivery chambers. The configuration of the artificial heart is compact, improves durability, reduces stress on the blood, and mimics the natural movement of human tissue, resulting in fewer side effects.

Description

Technical Field

[0001] The present disclosure generally relates to artificial hearts, and more particularly to implantable artificial hearts.

Background Art

[0002] Cardiogenic shock is a clinical condition accompanied by symptoms including shortness of breath, lack of strength, and swelling of the ankles. Gradually, severe cardiogenic shock situations include severe weight loss, muscle wasting, weakening of other organs (especially the kidneys or liver), immune response disorders, and deterioration of health through the risk of infection, ultimately leading to death. Generally, cardiogenic shock is caused by a disorder in the pumping function of myocardial tissue, resulting in a decrease in blood supply to tissues and organs, thereby causing a shortage in the supply of nutrients to the body, especially a shortage in the supply of oxygen.

[0003] Current treatments for cardiogenic shock are mostly based on drugs and cardiac surgical treatments such as heart transplantation and bypass surgery. Specifically, in drug-based treatments, some drugs have been found to be ineffective or even harmful, and drug treatment has limited benefits for severely damaged myocardium. Furthermore, the mortality rate of patients suffering from cardiogenic shock has not changed. Other treatments include cardiac resynchronization therapy. A typical treatment for end-stage cardiogenic shock is donor-based heart transplantation. Due to the shortage of donor organs, many patients are on the waiting list but do not receive organs. Furthermore, there has been intensive research in the fields of cell therapy and gene therapy, but their clinical applications seem to be almost non-existent.

[0004] In light of the above, artificial hearts configured to replace the functions of a human heart have been researched and developed. Mechanical circulatory assist devices are primarily used to support one side of the heart (most commonly the left side). These devices can be used as a bridge to transplantation or as a definitive treatment. Biventricular heart failure requires support or replacement of both ventricles (a "total artificial heart"). Conventional total artificial hearts are designed to be implanted as a temporary treatment, serving as a bridge to overcome the waiting period for a heart transplant. Furthermore, the construction of such artificial hearts is complex, as they involve the modification of complex medical devices, thereby limiting their use as a permanent solution. Conventional total artificial hearts also pose biocompatibility issues, resulting in blood interacting with rigid components, thereby increasing the risk of negative side effects such as thromboembolic events and unwanted bleeding events.

[0005] The present disclosure is directed to overcoming one or more of the limitations set forth above, or any other limitations associated with devices known in the art. Summary of the Invention [Problem to be solved by the invention]

[0006] The goal is to provide an implantable total artificial heart that is compact, durable, and mimics the natural movement of human tissue to potentially reduce stress on the blood, resulting in fewer side effects. [Means for solving the problem]

[0007] To better address one or more of these concerns, a first aspect of the present disclosure provides an implantable total artificial heart (hereinafter referred to as an artificial heart). The artificial heart includes a first delivery chamber defined with a first inlet and a first outlet. The artificial heart further includes a second delivery chamber positioned adjacent to the first delivery chamber and defined with a second inlet and a second outlet. The artificial heart further includes an actuator disposed between the first delivery chamber and the second delivery chamber. The actuator is configured to operate between a first operating state and a second operating state. The artificial heart also includes a plurality of first wires wound around the first delivery chamber and the actuator, and / or a plurality of second wires wound around the second delivery chamber and the actuator. Each of the plurality of first and / or second wires is configured to pressurize the first and / or second delivery chambers upon movement of the actuator between a first operating state and a second operating state for receiving fluid into and pumping fluid out of the first and second delivery chambers. The configuration of the artificial heart helps improve the durability of the artificial heart and helps mimic the natural movement of human tissue to potentially reduce stress on the blood and result in fewer side effects.

[0008] In an embodiment, the artificial heart includes at least one check valve disposed in each of the first inlet, the first outlet, the second inlet, and the second outlet, the check valves facilitating selective flow of fluid through the first inlet, the first outlet, the second inlet, and the second outlet based on an operating sequence of the artificial heart.

[0009] In an embodiment, the outer surfaces of the first delivery chamber, the second delivery chamber, and the actuator are defined with a plurality of passages. Each of the plurality of passages is configured to fix at least one first wire among the plurality of first wires and at least one second wire among the plurality of second wires. Further, each of the plurality of passages is configured to guide at least one first wire and at least one second wire with respect to the operation of the actuator between the first operating state and the second operating state.

[0010] In an embodiment, the first operating state corresponds to the contraction condition of the actuator regarding the depressurized state of the first delivery chamber and the second delivery chamber for passive drawing in of fluid into the first delivery chamber and the second delivery chamber, and the second operating state corresponds to the expansion condition of the actuator regarding the pressurized state of the first delivery chamber and the second delivery chamber for sending out of fluid from the first delivery chamber and the second delivery chamber.

[0011] In an embodiment, the first delivery chamber and the second delivery chamber are made of a fluid-tight inelastic material. These materials assist the artificial heart in mimicking the operation of the natural heart and in improving the durability of the artificial heart.

[0012] In an embodiment, the inner surfaces of the first delivery chamber and the second delivery chamber that come into contact with the fluid are made of a biocompatible material. The biocompatible material assists in reducing complications when implanted inside the body.

[0013] In an embodiment, the artificial heart includes a pump fluidly connected to the actuator, and the pump is configured to selectively operate the actuator in a pulsating manner between the first operating state and the second operating state.

[0014] In an embodiment, the artificial heart includes a control device communicatively connected to the pump, and the control device is configured to control the operation of the pump to provide a pulsating flow of the driving fluid to the actuator.

[0015] The above summary is illustrative only and not intended to be limiting in any way. In addition to the exemplary aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

[0016] The present invention is set forth in the appended claims, which embrace various improvements and equivalents thereof as would be apparent to those skilled in the art. The present disclosure, as well as the manner of use, further objects and advantages of the present invention, will be best understood by reference to the following detailed description of embodiments when read in conjunction with the accompanying drawings. Here, one or more embodiments will be described by way of example only, with reference to the accompanying exemplary drawings in which like reference numerals represent like elements.

Brief Description of the Drawings

[0017]

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DETAILED DESCRIPTION OF THE INVENTION

[0018] The drawings depict embodiments of the present disclosure for illustrative purposes only. Those skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein can be used without departing from the principles of the present disclosure described herein.

[0019] While embodiments in the present disclosure may take various improved and alternative forms, specific embodiments are shown by way of example in the drawings and described below. However, it should be understood that the specific embodiments are not intended to limit the present disclosure to the disclosed specific forms, and conversely, the present disclosure is intended to cover all improvements, equivalents, and alternatives within the scope of the present disclosure.

[0020] It is noted that those skilled in the art will be inspired by the present disclosure and will improve various features of the implantable artificial heart. Therefore, such improvements are part of the present disclosure. Thus, the drawings show only specific details regarding the understanding of the embodiments of the present disclosure that are not so detailed as to obscure the present disclosure for those skilled in the art who will benefit from the description herein.

[0021] As used in the present disclosure, the terms "comprising", "including", or any other variations thereof are intended to cover non-exclusive inclusion such that an implantable artificial heart including a listing of components may include not only those components but also other components not explicitly listed or other components inherent to such a device. In other words, one or more elements in a device following "comprising" do not exclude, without limitation, the presence of other elements or additional elements in the system or device.

[0022] In the following detailed description, embodiments of the present disclosure are described with reference to the accompanying drawings that form a part of this description, and those drawings are shown using specific embodiments that are examples in which the present disclosure may be implemented. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present disclosure, and it is understood that other embodiments may be utilized and changes may be made without departing from the scope of the present disclosure. Therefore, the following description should not be construed in a limiting sense.

[0023] Figure 1 shows a schematic view of an implantable total artificial heart (100) (hereinafter referred to as the artificial heart). The artificial heart (100) can be implantable into the circulatory system of a human body. The artificial heart (100) can include a first delivery chamber (101) and a second delivery chamber (102) positioned adjacent to each other. The first delivery chamber (101) is defined with a first inlet (108) and a first outlet (109), and the second delivery chamber (102) is defined with a second inlet (110) and a second outlet (111). The first inlet (108) and the second inlet (110) can each be configured to allow fluid flow into the first delivery chamber (101) and the second delivery chamber (102). Here, the fluid flow can refer to blood and blood vessels, and assist in the circulation of blood through the body of the subject (and thus the patient). Further, the first outlet (109) and the second outlet (111) can each be configured to allow fluid flow out of the first delivery chamber (101) and the second delivery chamber (102). In an embodiment, the first delivery chamber (101) and the second delivery chamber (102) are made of a fluid-tight non-stretchable material, and the inner surface in contact with the fluid (and thus blood) can be made of a biocompatible material having properties similar to those of human tissue. By way of example, the soft non-stretchable material can be, but is not limited to, woven Gore-Tex (registered trademark) (such as used in clinically applicable aortic grafts), woven Dyneema fibers, etc. The sizes of the first delivery chamber (101) and the second delivery chamber (102) of the artificial heart can be customized according to the requirements of the subject (and thus the patient). In the illustrated embodiment, the first delivery chamber (101) and the second delivery chamber (102) include a U-shaped cross-sectional profile, but since they can include any geometric profile or cross-section based on requirements, the U-shaped cross-sectional profile cannot be construed as a limitation.

[0024] As is apparent from FIG. 1, furthermore, the artificial heart (100) includes at least one check valve (106) disposed at each of a first inlet (108), a first outlet (109), a second inlet (110), and a second outlet (111). The at least one check valve (106) is structured such that the check valves (106) disposed at the first inlet (108) and the second inlet (110) open during the flow of fluid to the first delivery chamber (101) and the second delivery chamber (102), the check valves (106) disposed at the first outlet (109) and the second outlet (111) are closed, the check valves (106) disposed at the first inlet (108) and the second inlet (110) close during the flow of fluid from the first delivery chamber (101) and the second delivery chamber (102), and the check valves (106) disposed at the first outlet (109) and the second outlet (111) can be selectively operated to open. In an embodiment, the at least one check valve (106) can operate passively based on the pressure acting on the check valve (106). By way of example, the at least one check valve (106) can close when the pressure after the at least one check valve is higher than the pressure before it, and the at least one check valve (106) can open when the pressure after the at least one check valve is lower than the pressure before it. In the illustrated embodiment, one check valve is disposed at each of the first inlet (108), the first outlet (109), the second inlet (110), and the second outlet (111). However, this should not be construed as a limitation since two or more check valves (106) may be disposed at each of the first inlet (108), the first outlet (109), the second inlet (110), and the second outlet (111). By way of example, the at least one check valve (106) can be, but is not limited to, a clinically used biological or mechanical valve. Furthermore, the artificial heart (100) can include an actuator (103) that can be disposed between the first delivery chamber (101) and the second delivery chamber (102). The actuator (103) can be configured to operate between a first operating state and a second operating state.In the illustrated embodiment, as can be seen in FIGS. 1 and 3, the actuator (103) is defined to include a cylindrical contour, but the actuator (103) cannot be considered as a limitation since it may include any other geometric contour based on requirements. In the embodiment, the first operating state can correspond to the contraction condition of the actuator (103) (as seen in FIG. 1), and the second operating state can correspond to the expansion condition of the actuator (103) (as seen in FIG. 2). In the embodiment, the artificial heart (100) can include a pump (not shown in the figure) that can be fluidly connected to the actuator (103). The pump can be configured to direct a driving fluid, such as a medical liquid or air, from or towards the actuator (103) in order to operate the actuator (103) to the first and second operating states, respectively.

[0025] Referring further to FIG. 1, the artificial heart (100) may include a plurality of first wires (104) and a plurality of second wires (105). The plurality of first wires (104) are wound around the first delivery chamber (101) and the actuator (103), and the plurality of second wires (105) are wound around the second delivery chamber (102) and the actuator (103). In the illustrated embodiment, as best seen in FIGS. 2 and 4, the plurality of first wires (104) and the plurality of second wires (105) are wound around the first delivery chamber (101), the second delivery chamber (102), and the actuator (103) in a cross-sectional configuration, and the plurality of first wires (104) and the plurality of second wires (105) cross at a portion between the first delivery chamber (101) and the actuator (103) and at a portion between the second delivery chamber (102) and the actuator (103). However, this cannot be construed as a limitation since the plurality of first wires (104) and the plurality of second wires (105) can be wound around the first delivery chamber (101), the second delivery chamber (102), and the actuator (103) in any configuration such as a helix based on requirements. The plurality of first wires (104) and the second wires (105) can be configured to selectively pressurize and depressurize the first delivery chamber (101) and the second delivery chamber (102) in response to the movement of the actuator (103) between the first operating position and the second operating position. That is, the plurality of first wires (104) and the plurality of second wires (105) can be configured to depressurize the first delivery chamber (101) and the second delivery chamber (102) when the actuator (103) is in the first operating position (and thus in a contracted condition) to passively draw fluid into the first delivery chamber (101) and the second delivery chamber (102). Further, the plurality of first wires (104) and the plurality of second wires (105) are configured to pressurize the first delivery chamber (101) and the second delivery chamber (102) when the actuator (103) is in the second operating position (and thus in an expanded condition) to pump fluid out of the first delivery chamber (101) and the second delivery chamber (102).

[0026] In an embodiment, the first delivery chamber (101), the second delivery chamber (102), and the actuator (103) can be defined with a plurality of passages (107) on the outer surface. By way of example, the plurality of passages (107) can be, but are not limited to, slots, grooves, tunnels, tubes, etc. The plurality of passages (107) can be configured to fix at least one first wire of the plurality of first wires (104) and at least one second wire of the plurality of second wires (105). Further, the plurality of passages (107) are configured to guide at least one first wire and at least one second wire for scanning between the first operating state and the second operating state of the actuator (103) in order to selectively pressurize and depressurize the first delivery chamber (101) and the second delivery chamber (102) to create a pulsatile flow of fluid.

[0027] In an embodiment, the artificial heart (100) can include a control device (not shown in the figure) that can be communicatively coupled to the pump. The control device can be configured to control the operation of the pump to provide a pulsatile flow of the driving fluid to the actuator (103). This configuration assists the artificial heart (100) to mimic the heartbeat of a natural human heart.

[0028] In an embodiment, the first delivery chamber (101) can act as the right ventricle of a human heart, the second delivery chamber (102) can act as the left ventricle of a human heart, and the actuator (103) can act as a diaphragm. The actuator (103) can be operated at a desired interval between its first operating position and its second operating position such that the first delivery chamber (101) and the second delivery chamber (102) mimic the pulsation of a natural heart by depressurizing and pressurizing in correspondence with the operating interval of the actuator (103).

[0029] The configuration of the artificial heart (100) of the present disclosure makes the artificial heart (100) compact, unlike conventional total artificial hearts that use heavy mechanical components.

[0030] In an embodiment, the first delivery chamber (101) and the second delivery chamber (102) may include an inner layer or an outer layer. The inner layer, which can be in contact with the fluid, can be made of a biocompatible material, and the outer layer can be made of a soft inelastic material.

[0031] In an operational embodiment, as seen in FIG. 1, the actuator (103) can be in a first operating position where the actuator (103) is in a contracted condition. Due to the contracted state of the actuator (103), the plurality of first wires (104) and the plurality of second wires (105) are in a relaxed state, thereby exerting a minimum pressure or no pressure on the first delivery chamber (101) and the second delivery chamber (102). This results in the first delivery chamber (101) and the second delivery chamber (102) being in a decompressed state, which can facilitate the passive drawing in of fluid into the first delivery chamber (101) and the second delivery chamber (102). The fluid is passively drawn into the first delivery chamber (101) and the second delivery chamber (102) through the first inlet (108) and the second inlet (110) respectively, while the check valves (106) disposed at the first inlet (108) and the second inlet (110) are open and the check valves (106) disposed at the first outlet (109) and the second outlet (111) are closed. As an example, in the installed state of the artificial heart (100) in a human body, the first delivery chamber (101) can be configured to draw deoxygenated blood from the body, and the second delivery chamber (102) can be configured to draw oxygenated blood from the lungs. In an embodiment, the first delivery chamber (101) and the second delivery chamber (102) can remain in a decompressed state until the fluid fills the first delivery chamber (101) and the second delivery chamber (102). When the first delivery chamber (101) and the second delivery chamber (102) are filled with fluid, the actuator (103) can be actuated from the first operating position to a second operating position (as seen in FIG. 3).

[0032] In the second operating position, the actuator (103) can be inflated to increase the surface area of the actuator (103). This can result in tightly stretching a plurality of first wires (104) and second wires (105), exerting a force on each of the first delivery chamber (101) and the second delivery chamber (102). Due to the exertion of the force, the first delivery chamber (101) and the second delivery chamber (102) are pressurized, thereby being able to exert pressure on the fluid inside the first delivery chamber (101) and the second delivery chamber (102). This results in the stored fluid being sent out from the first delivery chamber (101) and the second delivery chamber (102). As an example, in the installed state of the artificial heart (100) in a human body, the first delivery chamber (101) can be configured to send deoxygenated blood to the lungs, and the second delivery chamber (102) can be configured to send oxygenated blood to the body. Further, the selective pressurization and depressurization operations of the first delivery chamber (101) and the second delivery chamber (102) are continuously performed to draw in and send out the fluid (and thus blood) in a pulsating manner, thereby being able to mimic the function of a natural heart.

[0033] Referring to FIGS. 5a - 5c here, FIGS. 5a - 5c show schematic views of an implantable artificial heart (100) according to other embodiments of the present disclosure. As seen in FIGS. 4a - 4c, the implantable artificial heart (100) may include a first delivery chamber (101), a second delivery chamber (102), and an actuator (103) disposed between the first delivery chamber (101) and the second delivery chamber (102). Further, the artificial heart (100) may include a plurality of wires wound around the first delivery chamber (101) and the actuator (103), and a plurality of second wires (105) wound around the actuator (103) and the second delivery chamber (102). As seen in FIGS. 5a, 5b, and 5c, the actuator (103) may include a circular contour, a triangular contour, an inverted triangular contour, and any other geometric contour based on requirements. The operation of the artificial heart (100) depicted in FIGS. 5a - 5c is similar to the operation of the artificial heart (100) as described with respect to FIGS. 1 - 4.

[0034] Referring to FIGS. 6a - 6c here, FIGS. 6a - 6c show schematic views of an implantable artificial heart (100) according to other embodiments of the present disclosure. As seen in FIGS. 6a - 6c, the implantable artificial heart (100) may include a first delivery chamber (101), a second delivery chamber (102), and an actuator (103) disposed between the first delivery chamber (101) and the second delivery chamber (102). Further, the artificial heart (100) may include a plurality of wires wound around the first delivery chamber (101) and the actuator (103), and a plurality of second wires (105) wound around the actuator (103) and the second delivery chamber (102). As seen in FIGS. 6a - 6c, the first delivery chamber (101) and the second delivery chamber (102) may include a bowl - shaped contour, an inverted triangular contour, and a triangular contour. The operation of the artificial heart (100) depicted in FIGS. 6a - 6c is similar to the operation of the artificial heart (100) as described with respect to FIGS. 1 - 4.

Example

[0035] Various experiments have been conducted on the implantable total artificial heart of the present disclosure. The implantable total artificial heart has undergone several in vitro tests. In one exemplary iteration of the test, the implantable total artificial heart was able to deliver a cardiac output of 5.7 l / min under normal in vitro hemodynamic conditions. Also, it has been found that the pulse rate was in the range between 60 and 80 bpm. Furthermore, it was noted that the implantable total artificial heart is preload-dependent, i.e., the stroke volume (the amount of blood pumped out of the ventricle of the implantable total artificial heart per heartbeat) increases when the preload increases and is comparable to that of a native human heart. Additionally, it has been found that the implantable total artificial heart is somewhat afterload-dependent. Afterload is the pressure against which the heart must work to eject blood during ventricular contraction.

[0036] The implantable total artificial heart has undergone in vitro experiments in a mock circulation loop (MCL) developed based on the Windkessel model. The mock circulation loop mimics various systemic and pulmonary afterloads and preloads, as well as systemic and pulmonary peripheral resistances and the compliance of the human heart.

[0037] In other iterations, to determine the preload sensitivity of the implantable total artificial heart, its preload was ranged from 4 mmHg to 18 mmHg. The preload was adjusted using an MCL setting filled with tap water. To maintain the same fluid height in the two preload tanks, a tube was placed as a shunt between both tanks. After testing each preload setting, the preload pressure was increased in 1 mmHg increments by adding more tap water to the preload tank. For each preload value, three runs consisting of 25 - 30 beats were performed using a pulse rate of 60 beats per minute (BPM) and a systolic time of 0.35 seconds. The pulmonary afterload and the systemic afterload were kept constant at mean pressures of 25 mmHg and 90 mmHg, respectively. Due to the change in stroke volume at different preload values, the resistance value was adjusted during the experiment to maintain a constant afterload. The mean stroke volume was calculated based on 6 beats for each of the three runs, and thus, overall based on 18 beats for each preload increment. To determine the afterload sensitivity of the implantable total artificial heart, the mean left afterload in the range between 50 - 120 mmHg was adjusted using an MCL setting filled with tap water. A shunt was placed between the two preload tanks and the total volume of water in the system was kept constant. The test was performed in one run where the left afterload was increased in approximately 10 mmHg increments by adjusting a resistance element that mimicked the systemic resistance. For each afterload, approximately 30 - 40 beats were captured at a pulse rate of 60 beats per minute and a systolic time of 0.3 seconds (the time period during which ventricular contraction occurs). The preload (6 mmHg) and the pulmonary resistance element were kept constant. The mean stroke volume was calculated based on three regions of 6 beats, and thus, overall based on 18 beats for each afterload increment. Additionally, a variable heart pulse rate test was performed to determine the effect of various pulse rates (30 - 100 BPM) on cardiac output. The MCL was filled with water and a shunt was placed between the two preload tanks. The test was started under optimal conditions with respect to pulse pressure, stroke volume, and the generated afterload at 60 BPM and a systolic time of 0.30 s. This test determined the settings of the pulmonary and systemic peripheral resistances.Subsequently, all pulse rates (30 - 100 BPM and a systolic time of 0.30 s) were tested without changing the resistance. The average stroke volume was calculated based on 10 beats for each run.

[0038] It was found that an implantable total artificial heart can achieve a maximum cardiac output of 5.7 L / min on the left side and 5.0 L / min on the right side under physiological hemodynamic conditions (Table 1, Figure 1). Intentionally, the cardiac output of the left ventricle was aimed to be made larger than that of the right ventricle. This is due to the large aortic pressure (left afterload), which is larger than the pulmonary artery pressure (right afterload), and a short circuit of some of the blood ejected by the left ventricle that directly refluxes to the left ventricle through the bronchial circulation. By adjusting the length of the wire around the right ventricle, it was possible to increase the left cardiac output relative to the right cardiac output.

[0039] The human heart balances its cardiac output by the Frank-Starling mechanism. When venous return (preload) increases in the human heart, an increase in cardiac contractility results in an increase in stroke volume. An implantable total artificial heart needs to have a similar mechanism that allows for an increased cardiac output when preload increases; otherwise, serious complications occur. Ideally, such a mechanism should operate passively to avoid the use of hardware and sensors that are bulky and prone to failure. In an implantable total artificial heart, soft materials are used, and a design is used where the ventricles are not fully expanded and filled at the end of diastole during normal operation, which essentially adds extensibility to the ventricles. It has been found that an implantable total artificial heart is sensitive to preload changes and passively increases stroke volume when venous return increases (Figs. 7a - 7f). For each mmHg increase in preload, the implantable total artificial heart pumps an extra 198 ml / min. This is within the range of the native human heart (241 ml / min / mmHg) (see Figs. 7a - 7f). For each mmHg increase in afterload, the left ventricle pumps less than 20 ml / min, which is less sensitive to afterload than the human heart (41 ml / min / mmHg). As the sensitivity of the implantable total artificial heart to afterload decreases, it becomes better at ensuring sufficient cardiac output over a wide range of afterloads. The resulting relevant experimental results were captured in the form of graph depictions in Figs. 7a - 7f.

[0040] Figure 7a shows the pressure curves measured during the operation of an implantable total artificial heart in a simulated circulatory loop. AOP = aortic pressure, PAP = pulmonary artery pressure, LAP = left atrial pressure, RAP = right atrial pressure. Figure 7b shows the cardiac output curves measured during the operation of an implantable total artificial heart in a simulated circulatory loop. LCO = left cardiac output, RCO = right cardiac output. Figure 7c shows the relationship between changing left preload and left stroke volume measured during the operation (continuous line) of an implantable total artificial heart in a simulated circulatory loop that mimics the preload sensitivity (dashed line) of the native heart. Figure 7d shows the relationship between changing systemic afterload and left stroke volume measured during the operation of an implantable total artificial heart in a simulated circulatory loop (continuous line) and in the native heart (dashed line). Figure 7e shows the relationship between changing heart rate and left stroke volume measured during the operation of an implantable total artificial heart in a simulated circulatory loop. Higher heart rates reduce stroke volume. Figure 7f shows the relationship between changing heart rate and left cardiac output measured during the operation of an implantable total artificial heart in a simulated circulatory loop. Optimal performance is obtained between 60 and 80 bpm.

[0041] Furthermore, during various tests in the double circulation simulation circuit, a study was conducted to confirm the effect of wire placement on cardiac output. The right cardiac output of the implantable total artificial heart was reduced compared to the left cardiac output by changing the wire length of the right ventricle. The tests were performed on three prototypes that were exact replicas of each other. First, these prototypes were tested with the same wire configuration and the same wire length for both ventricles. Each ventricle has five wires that extend parallel and spaced apart at the same distance. These prototypes were tested in the double circulation simulation circuit under physiological conditions, and it was noticed that the measured cardiac output varied from prototype to prototype (Table 1). The left cardiac outputs were 76 ml, 68 ml, and 91 ml for the three prototypes, respectively, and the right cardiac outputs were 84 ml, 76 ml, and 125 ml, respectively. Furthermore, it should be noted that with the same wire configuration for the left and right ventricles, all three prototypes had a larger right ventricular output compared to the left ventricular output. There was a right cardiac output by loosening the wires of the right ventricle. This would result in complete filling of the right ventricle and reduced ejection. By loosening the wires, the right cardiac output could be successfully reduced to 79 ml, 66 ml, and 83 ml, respectively (Table 1). By loosening the wires of the right ventricle, the left ventricular cardiac output increased to 79 ml, 84 ml, and 95 ml, respectively, in all cases (Table 1).

[0042]

Table 1

[0043] Regarding the use of substantially any plural and / or singular terms herein, one of ordinary skill in the art can convert from plural to singular and / or from singular to plural as appropriate for the context and / or application. Various singular / plural changes may be explicitly stated herein for clarity purposes.

[0044] Generally, the terms used herein, and especially those used in the appended claims (e.g., the body of the appended claims), are generally intended to be “open” terms (e.g., the term “comprising” should be construed as “including but not limited to”, the term “having” should be construed as “having at least”, the term “including” should be construed as “including but not limited to”, etc.), which is understood by those skilled in the art. Where a specific number of introduced claim recitations is intended, it is further understood by those skilled in the art that such intent is explicitly recited in the claim, and where there is no such recitation, there is no such intent. For example, for the sake of assistance in understanding, the following appended claims may include the use of the preamble phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to limit any particular claim that includes such an introduced claim recitation to an invention that includes only one such recitation, even when the introduction of a claim recitation by an indefinite article “a” or “an” is included in the same claim as the preamble phrases “one or more” or “at least one” and an indefinite article such as “a” or “an” (e.g., “a” and / or “an” should typically be construed to mean “at least one” or “one or more”), and the same applies to the use of a definite article used to introduce a claim recitation. Also, even when a specific number of introduced claim recitations is explicitly recited, those skilled in the art will recognize that such recitation should typically be construed to mean at least the recited number (e.g., a bare recitation of “two recitations” without other modifiers typically means at least two recitations, or two or more recitations).Furthermore, in examples where conventional expressions similar to "at least one of A, B, and C, etc." are used, generally, such syntax is intended in the sense that those skilled in the art understand the conventional expression (for example, "a system having at least one of A, B, and C" includes, without limitation, a system having only A, only B, only C, A and B together, A and C together, B and C together, and / or A, B, and C together). In those examples, when a conventional expression similar to "at least one of A, B, or C, etc." is used, generally, such syntax is intended in the sense that those skilled in the art understand the conventional expression (for example, "a system having at least one of A, B, or C" includes, without limitation, a system having only A, only B, only C, A and B together, A and C together, B and C together, and / or A, B, and C together). It should be further understood by those skilled in the art that substantially any disjunctive words and / or phrases presenting two or more alternative terms, whether in the description, claims, or drawings, are to be understood as contemplating the possibility of including one of the terms, any of the terms, or both terms. For example, "A or B" is understood to include the possibility of "A" or "B" or "A and B". Although various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for illustrative purposes only and are not intended to be limiting.

[0045]

Table 2

Description of Reference Numerals

[0046] 100 Implantable artificial heart 101 First delivery chamber 102 Second delivery chamber 103 Actuator 104 First wire 105 Second wire 106 Check valve 107 Passageway 108 First inlet 109 First outlet 110 Second inlet 111 Second outlet

Claims

1. An implantable total artificial heart (100), a first delivery chamber (101) defined with a first inlet and a first outlet, a second delivery chamber (102) positioned adjacent to the first delivery chamber (101) and defined with a second inlet and a second outlet, an actuator (103) disposed between the first delivery chamber (101) and the second delivery chamber (102) and configured to operate between a first operating state and a second operating state, a plurality of first wires (104) wound around the first delivery chamber (101) and the actuator (103), and / or a plurality of second wires (105) wound around the second delivery chamber (102) and the actuator (103) being provided, each of the plurality of first wires (104) and / or the second wires (105) being configured to selectively pressurize and depressurize the first delivery chamber (101) and / or the second delivery chamber (102) in response to the operation of the actuator (103) between the first operating state and the second operating state for drawing fluid into the first delivery chamber (101) and the second delivery chamber (102) and for discharging fluid from the first delivery chamber (101) and the second delivery chamber (102), the total artificial heart (100).

2. The total artificial heart (100) according to claim 1, comprising at least one check valve (106) disposed at each of the first inlet, the first outlet, the second inlet, and the second outlet.

3. The total artificial heart (100) according to claim 1, wherein outer surfaces of the first delivery chamber (101), the second delivery chamber (102), and the actuator (103) are defined with a plurality of passages (107).

4. The total artificial heart (100) according to claim 3, wherein each of the plurality of passages (107) is configured to fix at least one first wire of the plurality of first wires (104) and at least one second wire of the plurality of second wires (105).

5. Each of the plurality of passages (107) is configured to guide the at least one first wire and the at least one second wire with respect to the operation of the actuator (103) between the first operating state and the second operating state, the artificial heart (100) according to claim 3.

6. The first operating state corresponds to a contraction condition of the actuator (103) regarding a reduced pressure state of the first delivery chamber (101) and the second delivery chamber (102) for passive drawing in of the fluid into the first delivery chamber (101) and the second delivery chamber (102), the artificial heart (100) according to claim 1.

7. The second operating state corresponds to an expansion condition of the actuator (103) regarding a pressurized state of the first delivery chamber (101) and the second delivery chamber (102) for sending out of the fluid from the first delivery chamber (101) and the second delivery chamber (102), the artificial heart (100) according to claim 1.

8. The first delivery chamber (101) and the second delivery chamber (102) are configured to store fluid, the artificial heart (100) according to claim 1.

9. The first delivery chamber (101) and the second delivery chamber (102) are made of a fluid-tight inelastic material, the artificial heart (100) according to claim 1.

10. Inner surfaces of the first delivery chamber (101) and the second delivery chamber (102) are made of a biocompatible material, the artificial heart (100) according to claim 1.

11. A pump fluidly connected to the actuator (103), the artificial heart (100) according to any one of claims 1 to 10, comprising a pump configured to selectively operate the actuator (103) in a pulsating manner between the first operating state and the second operating state.

12. A control device communicatively connected to the pump, the artificial heart (100) according to any one of claims 1 to 11, comprising a control device configured to control the operation of the pump to provide a pulsating flow of drive fluid / gas to the actuator (103).

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