Electrode assembly patch for conductance and admittance measurements

Abstract

This disclosure aims to provide electrode assemblies, such as electrode assemblies for intravascular blood pumps. [Solution] Disclosed are electrode assembly patches configured for conductance and admittance measurement, and methods for manufacturing them. The technology provides a design and manufacturing method that enables conductance or admittance electrode assembly patches to be flexible, thin, and easily attached to intravascular blood pumps or other devices, with little or no change to the overall diameter, profile, and functionality of the device.

Description

Technical Field

[0005]

[0001] Cross - Reference to Related Applications This application claims priority to U.S. Provisional Application No. 63 / 088,784, filed Oct. 7, 2020; U.S. Provisional Application No. 63 / 173,709, filed Apr. 12, 2021; and U.S. Provisional Application No. 63 / 252,434, filed Oct. 5, 2021, the entire disclosures of which are incorporated herein by reference.

[0002] Technical Field The present disclosure relates to electrode assemblies, such as electrode assemblies for intravascular blood pumps.

Background Art

[0003] Background Intravascular blood pumps can be surgically or percutaneously introduced into a patient and used to deliver blood from one location in the heart or circulatory system to another location in the heart or circulatory system. For example, when deployed in the left heart, an intravascular blood pump can pump blood from the left ventricle of the heart into the aorta. Similarly, when deployed in the right heart, an intravascular blood pump can pump blood from the inferior vena cava into the pulmonary artery. Intravascular blood pumps can be driven by a motor located outside the patient via an elongated drive shaft or by an internal motor located within the patient. Some intravascular blood pumps can operate in parallel with the native heart to supplement cardiac output and partially or fully relieve the burden on the components of the heart.

Summary of the Invention

[0004] Brief Summary The present technology relates to an electrode assembly configured for conductance and admittance measurements, and a method of manufacturing the electrode assembly. In that regard, the present technology describes an electrode assembly adapted to be used with intravascular blood pumps and other devices where real - time ventricular volume measurements may be relevant.

[0005] In one embodiment, an electrode assembly patch that can be attached to an intravascular device is A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and It is equipped with.

[0006] In one embodiment, the first, second, third, and fourth electrode tabs extend outward from the first side of the strip in a first direction.

[0007] In one embodiment, the electrode assembly patch further comprises a first stabilizing tab extending outward from a second side of the strip in a second direction opposite to the first direction, and a second stabilizing tab extending away from the first stabilizing tab and outward from the strip in a second direction.

[0008] In one embodiment, the electrode assembly may further include a first nonconductive tab extending outward from the strip and a second nonconductive tab extending outward from the strip.

[0009] The first and second nonconductive tabs may be configured to ensure the separation and / or proper alignment of the electrode tabs (when the intravascular device is enclosed).

[0010] In addition, or alternatively, the first and second nonconductive tabs may be configured to enhance the adhesion of the electrode assembly patch and may be further configured to stabilize the electrode assembly patch when attached to a portion of an intravascular blood pump or other device.

[0011] The first and second non-conductive tabs may be non-conductive stabilizer tabs.

[0012] In one embodiment, the first stabilizing tab is positioned laterally between the first electrode tab and the second electrode tab.

[0013] In one embodiment, the second stabilizing tab is positioned laterally between the third electrode tab and the fourth electrode tab.

[0014] The second side may be the opposite of the first side.

[0015] In one embodiment, the electrode assembly patch is configured to be flexible.

[0016] The electrode assembly patch may have a sandwich configuration.

[0017] The electrode assembly patch may contain two or more layers; for example, the electrode patch may contain four layers.

[0018] The electrode assembly patch may have a multilayer structure.

[0019] The layers of the electrode patch assembly may be fused or welded to each other, for example, by thermoforming, or they may be bonded to each other.

[0020] The electrode assembly patch may include a substrate, such as a non-conductive substrate.

[0021] The electrode assembly patch may comprise one or more non-conductive layers and one or more conductive layers.

[0022] The base layer may be a non-conductive layer.

[0023] The electrode assembly may include an outer layer.

[0024] The outer layer of the electrode assembly patch may include one or more exposed electrodes.

[0025] In one aspect, the electrode assembly patch is configured to have a two-dimensional configuration in the non-deployed state and is further configured to have a three-dimensional configuration in the deployed state.

[0026] <0​​​​​​​​​​​​​​​​​​​​​​​​​​​​In one embodiment, the electrode assembly patch comprises four layers, each having a thickness of 5 μm.

[0034] In one embodiment, a system for determining admittance or conductance is: An intravascular device configured to be inserted into the patient's heart, A flexible electrode assembly patch attached to at least a portion of an intravascular device, comprising two or more electrodes configured to determine admittance and / or conductance, and It is equipped with.

[0035] In one embodiment, the flexible electrode assembly patch is A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and Includes.

[0036] In one embodiment, the first, second, third, and fourth electrode tabs extend outward from the first side of the strip in a first direction.

[0037] In one embodiment, the system further comprises a first stabilizing tab extending outward from a second side of the strip in a second direction opposite to the first direction, and a second stabilizing tab extending away from the first stabilizing tab and outward from the strip in a second direction.

[0038] In one embodiment, the flexible electrode assembly patch includes a strip having a proximal end and a distal end.

[0039] In one embodiment, the system further comprises a controller electrically connected to the electrode assembly patch, the controller being A current source and Memory and Coupled to memory, and An alternating current is supplied to the electrodes of the first electrode tab and the fourth electrode tab. Measure the voltage passing through the electrodes of the second electrode tab and the third electrode tab, and The admittance or conductance is determined based on the measured voltages of the second and third tabs. One or more processors configured as such It is equipped with.

[0040] In one embodiment, a system for determining admittance or conductance comprises an intravascular device configured to be inserted into the patient's heart, and an electrode assembly patch attached to at least a portion of the intravascular device. The electrode assembly patch is A first nonconductive layer configured to adhere to a portion of the intravascular device; a second layer having one or more wires; a third nonconductive layer configured to electrically insulate the one or more wires; and a fourth layer including one or more electrodes. It includes a multilayer structure that has the following features.

[0041] In one embodiment, the first nonconductive layer may be formed from a polymer material configured to be bonded, joined, and / or thermoformed to a portion of an intravascular device.

[0042] In one embodiment, each of the one or more wires is separated by a non-conductive material.

[0043] In one embodiment, one or more wires are formed from a conductive material.

[0044] In one embodiment, the conductive material includes platinum, gold, silver, and / or copper.

[0045] In one embodiment, one or more electrodes within the fourth layer are at least partially exposed.

[0046] In one embodiment, the multilayer structure includes four sandwich layers.

[0047] In one embodiment, the layers are bonded, joined, and / or thermoformed to one another.

[0048] In one embodiment, the electrode assembly patch is A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and Includes.

[0049] In one embodiment, the first, second, third, and fourth electrode tabs extend outward from the first side of the strip in a first direction.

[0050] In one embodiment, the system further comprises a first stabilizing tab extending outward from a second side of the strip in a second direction opposite to the first direction, and a second stabilizing tab extending away from the first stabilizing tab and outward from the strip in a second direction.

[0051] In one embodiment, the electrode assembly patch includes a strip having a proximal end and a distal end.

[0052] In one embodiment, the system further comprises a controller electrically connected to the electrode assembly patch, the controller being A current source and Memory and Coupled to memory, and An alternating current is supplied to the electrodes of the first electrode tab and the fourth electrode tab. Measure the voltage passing through the electrodes of the second electrode tab and the third electrode tab, and The admittance or conductance is determined based on the measured voltages of the second and third tabs. One or more processors configured as such It is equipped with.

[0053] In one embodiment, a method for forming a system for determining admittance or conductance includes the steps of wrapping and / or covering with a flexible electrode assembly patch at least a portion of an intravascular device configured to be inserted into a patient's heart; and attaching the flexible electrode assembly patch to a portion of the intravascular device.

[0054] For example, the cannula of an intravascular blood pump can be formed at least partially by an electrode assembly patch.

[0055] For example, the cannula may be formed at least partially by wrapping and / or enclosing an electrode assembly patch.

[0056] The cannula may have a support structure, and the electrode assembly patch may be wrapped around and / or enclose the support structure.

[0057] The support structure may comprise one or more strands or coils of shape memory material such as nitinol.

[0058] The electrode assembly patch can form a liquid-tight outer shell of the cannula.

[0059] In one embodiment, the attachment process includes thermoforming a flexible electrode assembly patch onto a portion of the intravascular device.

[0060] In one embodiment, the flexible electrode assembly patch includes a multilayer structure.

[0061] In one embodiment, the flexible electrode assembly patch is A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and Includes.

[0062] In one embodiment, the first, second, third, and fourth electrode tabs extend outward from the first side of the strip in a first direction.

[0063] In one embodiment, the flexible electrode assembly patch further comprises a first stabilizing tab extending outward from a second side of the strip in a second direction opposite to a first direction, and a second stabilizing tab extending away from the first stabilizing tab and outward from the strip in a second direction.

[0064] In one embodiment, the flexible electrode assembly patch includes a two-dimensional configuration before it is wrapped around and / or encloses the intravascular device. [Brief explanation of the drawing]

[0065] [Figure 1] Figure 1 shows a schematic perspective view of an exemplary intravascular blood pump configured for left ventricular support, according to the sphere of this disclosure. [Figure 2] Figure 2 shows a schematic perspective view of an exemplary intravascular blood pump configured for right heart support, according to the sphere of this disclosure. [Figure 3] Figure 3 is a functional block diagram of an exemplary system according to the aspects of this disclosure. [Figure 4A] Figure 4A shows a schematic top view of an exemplary electrode assembly patch according to the aspects of this disclosure. [Figure 4B] Figure 4B shows the selected dimensions of the electrode assembly patch in Figure 4A according to the aspect of this disclosure. [Figure 4C] Figure 4C shows a schematic cross-sectional view of the electrode assembly patch of Figure 4A along line XX, according to the aspect of this disclosure. [Figure 4D] Figure 4D shows a schematic cross-sectional view of the electrode assembly patch of Figure 4A along line YY, according to the plane of this disclosure. [Figure 4E] Figure 4A shows a schematic cross-sectional top view of the electrode assembly patch attached to the cannula of an intravascular pump. [Figure 5] A schematic perspective view is shown of the exemplary application of the electrode assembly patch of Figure 4A to a portion of the exemplary intravascular blood pump of Figure 1, according to the sphere of this disclosure. [Figure 6A]Figure 6A shows a schematic top view of an exemplary electrode assembly patch according to the aspects of this disclosure. [Figure 6B] Figure 6B shows the selected dimensions of the electrode assembly patch in Figure 6A according to the aspect of this disclosure. [Figure 7A] Figure 7A shows a schematic top view of an exemplary electrode assembly patch according to the aspects of this disclosure. [Figure 7B] Figure 7B shows the selected dimensions of the electrode assembly patch in Figure 7A according to the aspect of this disclosure. [Figure 8] Figure 8 shows a schematic top view of an exemplary electrode assembly patch according to the aspects of this disclosure. [Modes for carrying out the invention]

[0066] Detailed explanation Aspects of this disclosure will be described in detail with reference to diagrams that identify similar or identical elements by similar reference numbers. It should be understood that these aspects of the disclosure are merely examples and can be embodied in various forms. Well-known functions or structures are not described in detail to avoid obscuring the disclosure with unnecessary detail. Therefore, certain structural and functional details disclosed herein should not be construed as limitations, but merely as representative grounds for teaching those skilled in the art how to use this disclosure in various ways in substantially any appropriately detailed structure.

[0067] To provide an overall understanding of the systems, methods, and devices described herein, specific illustrative examples are provided. While intravascular blood pumps can be described in various examples, it will be understood that improved forms of this technology may also be adapted and applied to other types of medical devices, including electrophysiological studies and catheter ablation devices, angioplasty and stent placement devices, angiography catheters, peripherally inserted central venous catheters, central venous catheters, midline catheters, peripheral catheters, inferior vena cava filters, abdominal aortic aneurysm treatment devices, thrombectomy devices, TAVR delivery systems, cardiac treatment and assisted cardiac devices including balloon pumps, cardiac assisted cardiac devices implanted using surgical incisions, and any other venous or arterial-based introduction catheters and devices. As is well known, intravascular blood pumps can be surgically or percutaneously introduced into a patient to deliver blood from one location in the heart or circulatory system to another location in the heart or circulatory system. For example, when deployed in the left heart, an intravascular blood pump can pump blood from the left ventricle of the heart into the aorta. When deployed in the right heart, an intravascular blood pump can pump blood from the inferior vena cava into the pulmonary artery.

[0068] The inventors recognized the advantage of enabling continuous measurements while an intravascular blood pump is operating. For example, this advantage can be realized by determining ventricular volume while the intravascular pump or other device remains in the patient's heart. In some cases, ventricular volume may be used to improve the functionality of the intravascular blood pump and other devices. Ventricular volume may also be used to assess cardiac function and cardiac unloading.

[0069] According to embodiments described herein, ventricular volume may be determined using conductance or admittance methods. Such real-time ventricular volume measurements may then be used to generate a pressure-volume loop from which the level of cardiac function and cardiac unloading can be assessed. In some embodiments, ventricular volume may be assessed without the need to insert a dedicated conductance or admittance catheter.

[0070] In consideration of the above, the inventors have recognized the advantages of an electrode assembly patch (also referred to herein as the “patch”) that can be attached to or attached to an intravascular blood pump, for example, to the cannula of such a pump, for measuring ventricular volume. As to be understood, although illustrated and described as attachable to an intravascular blood pump, such an electrode assembly patch may, in other embodiments, be attachable to other suitable medical devices, such as a part of a catheter device. As to be further understood, although illustrated and described for measuring ventricular volume, the electrode assembly patch may be configured to measure other suitable parameters. Alternatively, the electrode assembly patch may be configured for tissue ablation. For example, such an electrode assembly patch may be attached to or attachable to a catheter ablation device.

[0071] As described herein, electrode assembly patches may be configured to maintain proper alignment and separation of one or more electrodes on the electrode assembly patch. For example, in some embodiments, an electrode assembly patch may include one or more internal electrodes for measuring voltage and one or more external electrodes configured to induce current (one of the electrodes being used as ground). In such embodiments, the electrode assembly patch may allow the distance between the internal electrodes to be maintained fixed relative to each other and to be maintained at a predetermined distance that is as large as possible. In some embodiments, the electrode assembly patch may also allow the distance between the internal electrodes and the external electrodes to be fixed relative to each other. In some embodiments, the electrode assembly patch may allow the electrodes to be arranged in series. The electrode assembly patch may also be configured not to encircle the entire circumference of the device when attached to the device (e.g., not to include an annular shape).

[0072] In some embodiments, the electrode assembly patch includes a flexible structure. For example, as disclosed herein, the electrode assembly patch may wrap around the outside of a device (e.g., a cannula), be folded around the outside of the device (e.g., a cannula), be wound (e.g., spirally), or otherwise positioned to install the electrode assembly patch on the device. In such embodiments, the electrode assembly patch may have a two-dimensional configuration when unfolded and a three-dimensional configuration when unfolded.

[0073] In some embodiments, the electrode assembly patch may include a multilayer structure. In such embodiments, the electrode assembly patch may allow the wiring to be completely enclosed and routed through the multilayer structure to a desired location on the device (e.g., to the discharge cage). In such embodiments, at least a portion of the electrode may be exposed. In some embodiments, the electrode assembly patch may also include a non-conductive layer.

[0074] In some embodiments, the electrode assembly patch is configured to be thin such that there is little or no change in the outer diameter of the device (e.g., cannula) after the electrode assembly patch is attached. In such embodiments, the thin configuration may result in little or no change in the overall profile and functionality of the device.

[0075] In some embodiments, the electrode assembly patch may be configured to facilitate attachment to the device (e.g., to the cannula). For example, as described herein, the electrode assembly patch may be thermoformed, bonded, joined, or otherwise appropriately attached to the outer surface of the device (e.g., to the cannula).

[0076] In some embodiments, the electrode assembly patch may include one or more tabs that allow for proper attachment of the electrode assembly patch to the device and proper spacing between electrodes. In some embodiments, the tabs may also provide mechanical stability to the electrode assembly patch while it is attached to the device.

[0077] Figure 1 shows an exemplary intravascular blood pump 100 adapted for left ventricular support in accordance with the present disclosure. In this regard, the intravascular blood pump 100 includes an elongated catheter 102, a motor 104, a cannula 110, a blood inflow cage 114 positioned at or near the distal end 112 of the cannula 110, a blood outflow cage 106 positioned at or near the proximal end 108 of the cannula 110, and an optional non-traumatic extension 116 positioned at the distal end of the blood inflow cage 114.

[0078] The motor 104 is configured to rotate an impeller (not shown) to generate sufficient suction force to draw blood into the cannula 110 through the blood inflow cage 114 and to drain blood from the cannula 110 through the blood outflow cage 106. In this regard, the impeller may be positioned distal to the blood outflow cage 106, for example, within the proximal end 108 of the cannula 110, or within a pump housing 107 coupled to the proximal end 108 of the cannula 110. In some aspects of this technology, instead of the impeller being driven by the internal motor 104, the impeller may be coupled to an elongated drive shaft driven by a motor located outside the patient.

[0079] The catheter 102 may house wires connecting the motor 104 to one or more electrical controllers or other sensors. Alternatively, if the impeller is driven by an external motor, an elongated drive shaft may pass through the catheter 102. The catheter 102 may also function as a conduit for one or more wires (e.g., wire 502 in Figure 5, later described) that connect the electrodes described herein to one or more controllers (e.g., included in controller 302 in Figure 3, later described) located outside the patient's body, a power supply, etc. The catheter 102 may also include a purge fluid conduit, a lumen configured to receive a guidewire, and the like.

[0080] The blood inflow cage 114 includes one or more openings or openings configured to allow blood to be drawn into the cannula 110 when the motor 104 is operating. Similarly, the blood outflow cage 106 also includes one or more openings or openings configured to allow blood to exit the intravascular blood pump 100 and out of the cannula 110. The blood inflow cage 114 and the blood outflow cage 106 may be made of (one or more) any suitable biocompatible material. For example, the blood inflow cage 114 and / or the blood outflow cage 106 may be formed from a biocompatible metal such as stainless steel or titanium, or a biocompatible polymer such as polyurethane. In addition, the surfaces of the blood inflow cage 114 and / or the blood outflow cage 106 may be treated in a variety of ways, including but not limited to etching, texturing, or coating or plating with another material. For example, the surfaces of the blood inflow cage 114 and / or the blood outflow cage 106 may be laser textured.

[0081] The cannula 110 may include a flexible hose portion. For example, the cannula 110 may be composed at least partially of polyurethane material. In addition, the cannula 110 may include shape memory material. For example, the cannula 110 may comprise a combination of polyurethane material and one or more strands or coils of shape memory material such as nitinol. The cannula 110 may be formed to include one or more bends or curves in its relaxed state, or it may be configured to be straight in its relaxed state. In this regard, in the exemplary arrangement shown in Figure 1, the cannula 110 has a single pre-formed anatomical bend 118 based on the portion of the left heart where it is intended to operate. Despite this bend 118, the cannula 110 may still be flexible and thus be able to be straightened (e.g., during insertion on a guidewire) or further bent (e.g., in patients with narrower anatomical dimensions). Furthermore, in this regard, the cannula 110 may include a shape memory material configured to allow the cannula 110 to have different shapes (e.g., straight or nearly straight) at room temperature, and to form a bent portion 118 when the shape memory material is exposed to the heat of the patient's body.

[0082] The non-traumatic extension 116 can assist in stabilizing and positioning the intravascular blood pump 100 in the correct position within the patient's heart. The non-traumatic extension 116 may be solid or tubular. If tubular, the non-traumatic extension 116 may be configured to allow a guidewire to be passed through the non-traumatic extension 116 in order to further assist in positioning the intravascular blood pump 100. The non-traumatic extension 116 may be of any suitable size. For example, the non-traumatic extension 116 may have an outer diameter in the range of 4 to 8 Fr. The non-traumatic extension 116 may be made of at least partially flexible material and may have any suitable shape or configuration, such as a straight configuration, a partially curved configuration, or a pigtail-shaped configuration as shown in the example in Figure 1. The non-traumatic extension 116 may also have sections with different rigidities. For example, the non-traumatic extension 116 may include a proximal section having sufficient rigidity to prevent buckling, thereby holding the blood inflow cage 114 in a desired position, and a distal section that is softer and has lower rigidity, thereby providing a non-traumatic tip for contact with the patient's heart wall and enabling guidewire loading. In such a case, the proximal and distal sections of the non-traumatic extension 116 may be made of different materials or of the same material that has been treated to provide different rigidities.

[0083] Notwithstanding the foregoing, as previously stated, the non-traumatic extension 116 is of arbitrary construction. In this regard, the technology may also be used with intravascular blood pumps and other intracardiac devices that include extensions of different types, shapes, materials, and qualities. Similarly, the technology may be used with intravascular blood pumps and other intracardiac devices that do not have any type of distal extension.

[0084] The intravascular blood pump 100 may be inserted percutaneously. For example, when used for left ventricular support, the intravascular blood pump 100 may be inserted by catheterization through the femoral or axillary artery into the aorta, across the aortic valve, and into the left ventricle. Once positioned in this manner, the intravascular blood pump 100 can deliver blood from a blood inflow cage 114, which may be placed in the left ventricle, to a blood outflow cage 106, which may be placed in the ascending aorta, through a cannula 110. In some aspects of this technology, the intravascular blood pump 100 may be configured such that a bend 118 abuts against a predetermined part of the patient's heart when the intravascular blood pump 100 is in the desired position. Similarly, a non-traumatic extension 116 may be configured to abut against different predetermined parts of the patient's heart when the intravascular blood pump 100 is in the desired position.

[0085] Figure 2 shows an exemplary intravascular blood pump 200 adapted for right heart support in accordance with the present disclosure. In this regard, the intravascular blood pump 200 includes an elongated catheter 202, a motor 204, a cannula 210, a blood inflow cage 214 positioned at or near the proximal end 208 of the cannula 210, a blood outflow cage 206 positioned at or near the distal end 212 of the cannula 210, and an optional non-traumatic extension 216 positioned at the distal end of the blood outflow cage 206.

[0086] Similar to the exemplary blood pump in Figure 1, the motor 204 is configured to rotate an impeller (not shown) to generate sufficient suction force to draw blood into the cannula 210 through the blood inflow cage 214 and to drain blood from the cannula 210 through the blood outflow cage 206. In this regard, the impeller may be located distal to the blood inflow cage 214, for example, within the proximal end 208 of the cannula 210, or within a pump housing 207 coupled to the proximal end 208 of the cannula 210. Again, in some aspects of this technology, instead of the impeller being driven by the internal motor 204, the impeller may be coupled to an elongated drive shaft driven by a motor located outside the patient.

[0087] The cannula 210 in Figure 2 may serve the same purposes as the cannula 110 in Figure 1, and may have the same properties and features as described above. However, in the exemplary arrangement shown in Figure 2, the cannula 210 has two pre-formed anatomical bends 218, 220 based on the portion of the right heart in which it is intended to operate. Again, despite the presence of the bends 218, 220, the cannula 210 may still be flexible and thus be able to be straightened (e.g., during insertion on a guidewire) or further bent (e.g., in patients with narrower anatomical dimensions). Furthermore in this regard, the cannula 210 may include a shape memory material configured to allow the cannula 210 to have different shapes (e.g., straight or nearly straight) at room temperature, and to form the bends 218 and / or 220 when the shape memory material is exposed to the heat of the patient's body.

[0088] The catheter 202 and non-traumatic extension 216 in Figure 2 may serve the same purposes as those described above with respect to the catheter 102 and non-traumatic extension 116 in Figure 1, and may have the same properties and features. Similarly, the blood inflow cage 214 and blood outflow cage 206 in Figure 2 are similar to the blood inflow cage 114 and blood outflow cage 106 in Figure 1, except that they are located at the opposite end of the cannula from those in Figure 1, and therefore may have the same properties and features described above.

[0089] Similar to the exemplary blood pump in Figure 1, the intravascular blood pump 200 in Figure 2 may also be inserted percutaneously. For example, when used for right heart support, the intravascular blood pump 200 may be inserted by catheterization through the femoral vein into the inferior vena cava, through the right atrium, across the tricuspid valve, into the right ventricle, and through the pulmonary valve into the pulmonary artery. When positioned in this manner, the intravascular blood pump 200 can deliver blood from a blood inflow cage 214, which may be placed in the inferior vena cava, to a blood outflow cage 206, which may be placed in the pulmonary artery, through a cannula 210.

[0090] As described herein, an intravascular pump may be configured to assess ventricular volume (and thus cardiac function and cardiac unloading) via one or more electrodes that induce an electric current and one or more electrodes that measure voltage while remaining in the patient's heart. Figure 3 is a functional block diagram of an exemplary system according to the aspects of this disclosure. In the example of Figure 3, the system 300 includes an intravascular blood pump 318 and a controller 302. The intravascular blood pump 318 can take any form, including those shown in the exemplary intravascular blood pumps 100 and 200 in Figure 1 or Figure 2, respectively. As shown in the example of Figure 3, the intravascular blood pump 318 in Figure 3 may include one or more pressure sensors 322 and a motor 324. The intravascular blood pump 318 may include an attached electrode assembly patch 320, such as the electrode assembly patches 400, 600, 700, and 800 shown in Figures 4A, 4B, 6A, 6B, 7A, 7B, and 8.

[0091] As described herein, the electrode assembly patch 320 may include one or more electrodes. For example, as shown in Figure 4D, the electrode assembly patch 400 may include at least two electrodes configured to supply (e.g., induce) current (e.g., electrodes 454a, 454d in Figure 4D, electrodes of electrode tabs 606a, 606d in Figure 6, electrodes of electrode tabs 706a, 706d in Figure 7, and electrodes 806a, 806d in Figure 8, as will be described further below) and at least two electrodes configured to measure voltage (e.g., electrodes 454b, 454c in Figure 4D, electrodes of electrode tabs 606b, 606c in Figure 6, electrodes of electrode tabs 706b, 706c in Figure 7, and electrodes 806b, 806c in Figure 8, as will be described further below).

[0092] In some embodiments, one or more pressure sensors 322 may include any suitable type of pressure sensor or combination of pressure sensors configured to measure the pressure on or near the electrodes of the electrode assembly patch 320. Thus, in some aspects of the Art, (one or more) pressure sensors 322 may be a single pressure sensor located at or near the distal end of a cannula (e.g., cannulas 110 and 210). Similarly, in some aspects of the Art, (one or more) pressure sensors 322 may be a combination of pressure sensors whose readings can be combined to derive an estimated pressure near the electrode set of the electrode assembly patch 320.

[0093] In the example in Figure 3, the controller 302 may include a memory 306 for storing instructions 308 and data 310, an instrument interface 312 with the intravascular blood pump 318, a current source 314, a power supply 316, and one or more processors 304 coupled to a voltage measurement unit 317. The instrument interface 312 may be any suitable type of interface between the controller 302 and the intravascular blood pump 318 that can supply current from the current source 314 to the electrodes of the electrode assembly patch 320, receive voltage readings from the electrodes of the electrode assembly patch 320, receive pressure readings from (one or more) pressure sensors 322, and supply power to the motor 324 from the power supply 316. The current source 314 may be any instrument capable of providing a suitable current for performing conductance or admittance measurements. For example, the current source 314 may be configured to supply substantially constant alternating currents of 10 μA and 100 μA at 20 kHz. As can be understood, in some aspects of this technology, the current source 314 and the power supply 316 may be implemented as a single unit configured to supply power to the motor 324 and also to supply appropriate current to the electrodes of the electrode assembly patch 320.

[0094] The controller 302 may take any form. In this regard, the controller 302 may consist of a single modular unit, or its components may be distributed among two or more physical units. The controller 302 may further include any other components commonly used in connection with computing devices, such as a user interface. In this regard, the controller 302 may have a user interface that includes one or more user inputs (e.g., buttons, touchscreens, keypads, keyboards, mice, microphones, etc.), one or more electronic displays (e.g., monitors or information displays with screens, any other electrical devices that operate to display one or more lights, etc.), one or more speakers, chimes, or other audio output devices, and / or one or more other output devices such as vibration elements, pulse elements, or tactile elements.

[0095] One or more processors 304 and memory 306 described herein may be implemented on any type of computing device (one or more), including customized hardware or any type of general-purpose computing device. Memory 306 may be any non-temporary type capable of storing information accessible by one or more processors 304, such as a hard drive, memory card, optical disc, solid-state drive, tape memory, or similar structure.

[0096] Instruction 308 may include programming configured to receive and process readings from the electrode set 320 and one or more pressure sensors 322. In this regard, instruction 308 may include programming necessary to calculate the voltage drop and / or phase shift between the voltage reading electrodes of the electrodes of the electrode assembly patch 320 (for example, electrodes 454b, 454c in Figure 4D, electrodes of electrode tabs 606b, 606c in Figure 6, electrodes of electrode tabs 706b, 706c in Figure 7, and electrodes 806b, 806c in Figure 8) (using, for example, the voltage measurement unit 317); calculate conductance or admittance based on the readings received from the electrodes of the electrode assembly patch 320 and one or more pressure sensors 322; estimate ventricular volume based on the conductance or admittance calculation; generate a pressure-volume loop based on the estimated ventricular volume; generate an estimate of cardiac function based on the generated pressure-volume loop; and / or generate an estimate of ventricular unloading provided by the operation of the intravascular blood pump 318 based on the generated pressure-volume loop. The controller 302 may be further configured to store in memory 306 readings from the electrode set 320 and one or more pressure sensors 322, as well as calculations based on the readings. In some embodiments, the controller 302 may also be configured to transmit readings from the electrodes of the electrode assembly patch 320 and / or generated estimates of ventricular unloading or cardiac function to an external device, for example, a user interface (not shown) and / or a cloud-based storage device in which the readings and / or generated estimates can be stored.

[0097] Data 310 may include any relevant data for operating the intravascular blood pump 318. For example, data 310 may include lookup tables and other data related to the interpretation of signals from the intravascular blood pump 318, calibration and / or interpretation of signals from electrodes of the electrode assembly patch 320 or one or more pressure sensors 322, etc.

[0098] Figure 4A shows an exemplary electrode assembly patch 400 in a aspect of the present disclosure. As shown in Figure 4D, the exemplary electrode assembly patch 400 is configured as a multilayer strip 404 extending longitudinally (for example, in the direction of line YY) from a proximal end 402 to a distal end 410.

[0099] In some embodiments, as shown in Figures 4A and 4B, the electrode assembly patch 400 may include one or more tabs extending outward from the strip. For example, one or more tabs may extend outward from a first side of the strip in a first direction, and one or more tabs may extend outward from a second opposite side of the strip in a second opposite direction. In some embodiments, the tabs may extend to the left and right of the strip.

[0100] As shown in Figures 4A and 4B, in some embodiments, the tabs may be perpendicular to the strip. In other embodiments, one or more tabs may extend at other suitable angles relative to the strip. For example, the tabs may extend at ±45 degrees with respect to the transverse axis of the strip. In some embodiments, as shown in Figures 4A and 4B, the tabs may be positioned parallel to one another. As can be understood, in other embodiments, one or more tabs may extend in a direction non-parallel to another tab (or possibly more tabs).

[0101] As shown in Figure 4A, the tabs labeled 406a, 406b, 406c, and 406d, extending to the right of strip 404, are electrode tabs. For the purposes of this specification, an electrode tab includes a tab in which an electrode extends at least partially. As described herein, the electrode may induce an electric current in some embodiments and / or measure a voltage in other embodiments. In some embodiments, the tabs labeled 408a and 408b, extending to the left of the strip, are non-conductive stabilizer tabs. In some embodiments, non-conductive stabilizer tabs may be used to ensure the separation and / or proper alignment of the electrode tabs (when encasing an intravascular device) and to enhance and stabilize the adhesion of the electrode assembly patch when attached to a part of an intravascular blood pump or other device (e.g., using thermoforming, bonding, adhesive, etc.).

[0102] In some embodiments, as shown in Figure 4E, when attached to the intravascular device, the electrode tab (e.g., electrode tab 406a in Figure 4E) is configured to enclose only a portion of the intravascular device 470. That is, in such embodiments, the electrode tab does not surround the entire circumference of the device. In other words, in such embodiments, the electrodes of the electrode assembly patch do not form a closed ring when the electrode assembly patch is attached to the device (e.g., the distal end of the electrode tab is separated from the adjacent portion of the strip).

[0103] The example in Figure 4A shows all electrode tabs extending to the right of strip 404 and all stabilizer tabs extending to the left of strip 404, but it will be understood that any suitable arrangement may be used. For example, in some aspects of this technology, the orientation of each tab may be reversed from that shown in Figure 4A. Similarly, in some aspects of this technology, the tabs labeled 406a, 406b, and 408b may extend to the left of strip 404, respectively, and the tabs labeled 408a, 406c, and 406d may extend to the right of strip 404, respectively.

[0104] The example in Figure 4A shows an electrode assembly patch having both electrode tabs and stabilizer tabs, but in other embodiments, the electrode assembly patch may include only electrode tabs. As can be understood, in such examples, the electrode tabs may have any suitable arrangement relative to the strip.

[0105] As shown in Figure 4A, the strip 404 may have a tapered section at or near the proximal end 402. In such embodiments, the strip 404 may be wider at or near the proximal end 402 than at the distal end 410 (or another suitable portion of the strip). In some embodiments, the wider portion at or near the proximal end 402 may be used to weld or join an external wire (e.g., wire 504 in Figure 5) to a contact located at or near the proximal end 402 (e.g., contacts 462a-462d in Figure 5). If one or more wires are welded to each contact, a further layer of non-conductive material may be applied over the weld to electrically insulate the exposed wire and / or weld from the ambient fluid.

[0106] The exemplary electrode assembly patch 400 in Figure 4A is shown with four electrode tabs, but in some aspects of this technology, the electrode assembly patch 400 may be implemented with additional or fewer electrode tabs (for example, so that the total number of electrode tabs is 2, 6, 8, 10, 12, etc.). In addition, although the exemplary electrode assembly patch 400 is shown having four layers in Figures 4C and 4D, any other number of layers and conductor arrangements may be used.

[0107] The exemplary electrode assembly patch 400 in Figure 4A may be fitted to any suitable intravascular blood pump, and its dimensions may be customized to suit the device to which the electrode assembly patch 400 is attached. In this regard, Figure 4B shows a copy of the exemplary electrode assembly patch 400 of Figure 4A, annotated to show various features and dimensions to which the assembly may be modified to fit different intravascular blood pumps or other devices. For illustrative purposes, each of the features and dimensions shown in Figure 4B is described below using the assumption that the electrode assembly patch will be attached (e.g., thermoformed, bonded, glued, etc.) to the outer surface of the cannula of the intravascular blood pump (e.g., cannula 110 in Figure 1). It is further assumed that the cannula has a length of at least 70 mm and a diameter of approximately 14 Fr (4.67 mm). Figures 4A and 4B show the same exemplary electrode assembly patch 400, but for clarity, elements identified in Figure 4A are again not identified in Figure 4B.

[0108] Using the above assumptions, the electrode assembly patch 400 in Figure 4B may have a total length 428 of 70 mm. The proximal end 402 of the strip 404 may have a contact patch that has a width 420 of 6 mm and a length 422 of 2.5 mm, and then tapers to a width 442 of 3 mm. The tapered section may have a length 424 of 2.5 mm and a taper angle 426 of approximately 149°.

[0109] The four electrode tabs may each have a width of 3 mm, and may be arranged such that the first tab and the second tab (406a and 406b in Figure 4A) and the third tab and the fourth tab (406c and 406d in Figure 4A) are separated by a distance of 3 mm, and the second tab and the third tab (406b and 406c in Figure 4A) are separated by a distance of 10 mm. Thus, the set of four electrode tabs may have a total length of 28 mm. In some aspects of this technology, it may be desirable to maximize the distance between the second tab and the third tab (406b and 406c in Figure 4A). Thus, if the dimensions of the intravascular blood pump and / or the patient's anatomical form allow for an increase in the distance, it may be advantageous to do so, provided that all four electrode tabs can still fit within the volume to be measured (e.g., the patient's left ventricle).

[0110] The length 444 of each electrode tab may be configured such that when the tab wraps around the outside of the cannula, the end of each tab approaches the left edge of the strip but does not overlap. In this regard, assuming a cannula with a diameter of 14Fr has a circumference of approximately 14.66 mm and the strip has a width 442 of 3 mm, each electrode tab may have a length 444 of 11.5 mm such that a gap of approximately 0.16 mm remains when the tab wraps around the cannula. Avoiding overlap is not essential to this technique, but it will be understood that it may provide advantages in certain cases. For example, if the electrode assembly patch 400 is thermoformed onto a portion of an intravascular blood pump, overlap may cause the end of the electrode tab to melt together with a portion of the strip, which may form a short circuit between the electrode (e.g., electrode 454a in Figure 4C) and one of the conductors for another electrode (e.g., wires 456b, 456c, or 456d in Figure 4C). Similarly, since the material of the electrode assembly patch 400 may not adhere to itself strongly enough to adhere to the cannula (or any other part of the intravascular blood pump to which it may be attached), overlaps can create fragile areas where the tab may peel off and begin to delaminate. Furthermore, avoiding overlaps may be desirable to minimize the overall diameter of the intravascular blood pump and / or to achieve a smoother outer profile when the electrode assembly patch 400 is attached to the surface of the intravascular blood pump.

[0111] In the examples in Figures 4A and 4B, the first stabilizer tab (408a in Figure 4A) is positioned to fit between the distal ends of the first and second electrode tabs (406a and 406b in Figure 4A) when the electrode assembly patch 400 encloses the intravascular blood pump, and the second stabilizer tab (408b in Figure 4A) is positioned to fit between the distal ends of the third and fourth electrode tabs (406c and 406d in Figure 4A). Thus, in this example, the length 440 of each stabilizer tab may be 5 mm, and the width 434 may be 2.5 mm. Using a width 434 of 2.5 mm makes it possible to leave a space of 0.25 mm between the edge of each stabilizer tab and the two adjacent electrode tabs. Here again, leaving a space between the edge of the stabilizer tab and the adjacent electrode tab may be advantageous in order to avoid overlaps during manufacturing that could negatively affect the overall diameter and / or smoothness of the outer profile or create a weakness in the junction between the electrode assembly patch 400 and the cannula.

[0112] Although each electrode tab is shown in Figure 4A as having the same width and length, it will be understood that the width and / or length of the tabs may vary from tab to tab (or between subsets of tabs). Similarly, although each stabilizer tab is shown in Figure 4A as having the same width and length, it will be understood that the width and / or length of the tabs may vary from tab to tab. Also, although each electrode and each stabilizer tab is shown as having a uniform width, in other embodiments, one or more tabs may have a width that varies between the proximal and distal ends (see, for example, the electrode tabs in Figure 6A). For the purposes of this specification, the proximal end of a tab is the end of the tab closest to the strip.

[0113] Figures 4C and 4D show exemplary cross-sectional views of the electrode assembly patch of Figure 4A, according to the aspects of this disclosure. More specifically, Figure 4C shows an exemplary cross-sectional view of the electrode assembly patch of Figure 4A along line XX, thus showing a cross-section extending from the left edge 450 of the strip 404 to the right edge 452 of the electrode tab 406a. Figure 4D shows an exemplary cross-sectional view of the electrode assembly patch of Figure 4A along line YY, thus showing a longitudinal cross-section extending from the proximal end 402 to the distal end 410 of the electrode assembly patch of Figure 4A.

[0114] As shown in the example in Figure 4C, the electrode assembly patch may comprise four sandwich layers (labeled 1-4 in Figures 4C and 4D). Layer 1 may be a non-conductive (dielectric) layer configured to adhere to a specific part of the intravascular blood pump (or other device) and electrically insulate the second layer from the surface to which the electrode assembly patch is attached. For example, if the electrode assembly patch is attached to a flexible cannula (e.g., cannula 110 in Figure 1) of an intravascular blood pump (e.g., intravascular blood pump 100 in Figure 1), Layer 1 may be made from a polymer (e.g., a polyamide film) suitable for adhesion, bonding, or thermoforming to the cannula.

[0115] Layer 2 may include wires 456a to 456d, each of which passes between a contact patch (e.g., contact patch 462a) near the proximal end 402 of the electrode assembly patch and its respective electrode (454a to 454d). Wires 456a to 456d may be formed from any suitable metal or other conductive material such as platinum, gold, silver, or copper. As shown in Figure 4C, each of the wires 456a to 456d may be separated and isolated by a nonconductive material (all white areas in layers 1 to 4 represent nonconductive materials). In addition, the nonconductive material may also be used to fill the space between wire 456d and the left edge 450 of strip 404, and between 456a and the right edge of strip 404, so that wires 456a and 456d also remain insulated from the ambient fluid.

[0116] In some aspects of this technology, one or more portions of the nonconductive material in layer 2 may be obtained as a result of inserting nonconductive strips before fusing the layers of the electrode assembly patch together (e.g., using thermoforming). Similarly, in some aspects of this technology, when the layers of the electrode assembly patch are fused together using thermoforming, one or more portions of the nonconductive material in layer 2 may be obtained as a result of the nonconductive material melting and flowing into layer 2 from one or more adjacent layers (e.g., layer 1 or layer 3) during thermoforming. Here again, the nonconductive material may be a polymer (e.g., polyamide) or other suitable nonconductive material, including any of the nonconductive materials used in the other layers.

[0117] Layer 3 may be another non-conductive layer configured to electrically insulate wires 456a to 456d from layer 4, except where conductive bridges are provided to connect one of the wires (e.g., wire 456a) to its respective contact patch (e.g., contact patch 462a) or its respective electrode (e.g., electrode 454a). For example, as shown in Figures 4C and 4D, a conductive bridge 458a is provided in the portion of layer 3 near the electrode tab 406a for electrically connecting wire 456a to electrode 454a. Similarly, as shown in Figure 4D, a conductive bridge 460a is provided in the portion of layer 3 near the proximal end 402 for electrically connecting wire 456a to contact patch 462a. Again, the conductive bridges (e.g., 458a, 460a) may be formed from any suitable metal or other conductive material such as platinum, gold, silver, copper, etc.

[0118] As described above, one or more portions of the nonconductive material in layer 3 may be obtained from the insertion of nonconductive strips before the layers of the electrode assembly patch are fused together (e.g., using thermoforming). Similarly, in some aspects of the art, when the layers of the electrode assembly patch are fused together using thermoforming, one or more portions of the nonconductive material in layer 3 may be obtained as a result of the nonconductive material melting and flowing into layer 3 from one or more adjacent layers (e.g., layer 2 or layer 4) during thermoforming. Here again, the nonconductive material in layer 3 may be a polymer (e.g., polyamide) or other suitable nonconductive material, including any of the nonconductive materials used in the other layers.

[0119] Layer 4 may include electrodes 454a to 454d, each of which may be positioned to coincide with a corresponding electrode tab (406a to 406d). As shown in Figure 4D, each of electrodes 454a to 454d may be separated and isolated by a nonconductive material. Similarly, Figure 4C shows a small amount of nonconductive material between the left end of electrode 454a and the left edge 450 of strip 404, and another small amount of nonconductive material between the right end of electrode 454a and the right edge 452 of electrode tab 406a. However, in some aspects of the art, electrode 454a may extend along its entire length from the left edge 450 of strip 404 to the right edge 452 of electrode tab 406a.

[0120] The upper surfaces of each electrode 454a-454d may be exposed so that they can be used to supply current to the surrounding fluid (e.g., blood in the patient's left ventricle) or to sense a voltage from the surrounding fluid. Here again, any suitable metal or other conductive material such as platinum, gold, silver, copper, etc., may be used for electrodes 454a-454d. In addition, electrodes 454a-454d may include a combination of conductive materials. For example, in some aspects of this technology, electrodes 454a-454d may be formed from gold and then coated or plated with a thin (e.g., 100 nm) top layer of platinum.

[0121] As described above, one or more portions of the nonconductive material in layer 4 may be obtained from the insertion of nonconductive strips before the layers of the electrode assembly patch are fused together (e.g., using thermoforming). Similarly, in some aspects of the art, when the layers of the electrode assembly patch are fused together using thermoforming, one or more portions of the nonconductive material in layer 4 may be obtained as a result of the nonconductive material melting and flowing from an adjacent layer (e.g., layer 3) into layer 4 during thermoforming. Again, the nonconductive material in layer 4 may be a polymer (e.g., polyamide) or other suitable nonconductive material, including any of the nonconductive materials used in the other layers.

[0122] Each of layers 1 to 4 may have any appropriate thickness. For example, in some aspects of this technology, each layer may have a thickness of 5 μm so that the electrode assembly patch may have a total thickness of 20 μm. Similarly, in some aspects of this technology, each layer may have a thickness of 1 to 10 μm. However, although Figures 4C and 4D show layers of equal thickness, in some aspects of this technology, one or more of the layers may have a different thickness from the others. Similarly, although the examples in Figures 4C and 4D show layers of constant thickness, in some aspects of this technology, the thickness of the layers may vary from left to right or from proximal to distal. For example, in some aspects of this technology, layers 1 and 2 may be formed using a first preformed sheet having a conductive film bonded to a non-conductive (dielectric) base that has been etched so that only selected patches of the conductive film remain, and layers 3 and 4 may be similarly formed from a second preformed sheet of a similar composition. In such cases, when the two sheets are joined together using thermoforming, the non-conductive material from layers 1 and 3 flows into the adjacent layers 2 and 4, bonding the two sheets together and sealing off any remaining conductive material in layers 2 and 4. As a result, the thickness of the electrode assembly patch may differ slightly between areas with and without the conductive film.

[0123] In addition, the thickness and material of layers 1-4 may be selected to obtain material properties suitable for a given application. For example, if the electrode assembly patch is to be attached to a flexible section of an intravascular blood pump, such as a cannula (e.g., cannula 110 in Figure 1), a relatively thin layer (e.g., 5 μm) may be used in the non-conductive portion, and a relatively flexible material (e.g., polyamide) may be used, so that the entire electrode assembly patch can bend together with the section of the intravascular blood pump to which it is attached.

[0124] Figure 5 shows an exemplary application of the electrode assembly patch of Figure 4A to a portion of the exemplary blood pump of Figure 1, according to a part of the present disclosure. In that regard, Figure 5 shows a wire 502 routed along the outside of the motor 104, along one of the supports of the blood outflow cage 106, the wire 502 spreading out to become individual wires 504, each of which connects to one of the different contacts 462a-462d. In some parts of the present technology, the wire 502 may travel within an elongated catheter 102 (not visible in Figure 5) and exit at a point near the proximal end of the motor 104. As described above, a coating or layer of nonconductive material may be applied over the contact patches 462a-462d to insulate them from the ambient fluid. Similarly, in some parts of the present technology, a coating or layer of nonconductive material may also be applied over the wires 504. In some aspects of this technology, the nonconductive material may be a polymer sleeve (e.g., a polyamide sleeve) that is thermoformed to cover the wires 504 and / or contacts 462a-462d.

[0125] As can be understood, the electrode assembly patch may be bonded to contacts located at other suitable locations on the intravascular pump. For example, in one embodiment, the electrode assembly patch may extend to cover at least a portion of the outflow cage 106 and extend into the catheter of the intravascular blood pump. In such embodiments, the contacts and electrode assembly patch may be located within the catheter of the intravascular blood pump for connection.

[0126] In the example of Figure 5, the electrode assembly patch of Figure 4A is attached to the flexible cannula 110. As can be understood, the proximal end 402 of the strip 404 may be positioned near the proximal end 108 of the cannula 110, and the distal end 410 of the strip 404 may be positioned near the distal end 112 of the cannula 110. For example, in some embodiments, the distal end may be positioned near an inlet cage (not shown) attached to the distal end of the cannula. In addition, the electrode tabs 406a-406d are positioned distal to a pre-formed anatomical bend 118 within the cannula 110. In some aspects of the art, the intravascular blood pump 100 may be configured such that the anatomical bend 118 rests on or near the aortic valve. In such cases, the electrode tabs 406a to 406d can be positioned within the patient's left ventricle while the pump is operating, by placing them distal to a pre-formed anatomical bend 118, so that they can be used to measure left ventricular volume.

[0127] In some aspects of this technology, the electrode assembly patch may be configured and / or attached so that the wires 456a-456d within the strip 404 pass along the sides of the cannula (as opposed to passing outside or inside the anatomical bend 118). The electrode assembly patch may be formed to be thin and flexible (as described above), but by attaching it in this manner, the stress on the wires 456a-456d that could lead to breakage may be reduced, and / or the possibility of delamination of the electrode assembly patch due to bending of the cannula 110 may be reduced.

[0128] The electrode assembly patch may be attached to the cannula 110 using any suitable method such as bonding, adhesive, or thermoforming. For example, in some aspects of this technology, the electrode assembly patch shown in Figures 4A to 4D may be formed using one or more polyamides as a non-conductive material and gold as a conductive material (with or without platinum plating on the upper surface of electrodes 454a to 454d), or it may be thermoformed onto the outer surface of the cannula 110. In such cases, the electrode assembly patch may be placed over the cannula 110, covered with heat-shrink tubing, and heated until the polyamide of layer 1 (and potentially some or all of the polyamide at the edges of other layers) fuses with the material of the cannula 110 (e.g., polyurethane).

[0129] Figure 6A shows another exemplary electrode assembly patch 600 according to a aspect of the present disclosure. Here again, the exemplary electrode assembly patch 600 may be configured as a multilayer strip 604 having any suitable number and configuration of layers, including configurations based on the configurations described above with respect to Figures 4C and 4D. Similar to the example in Figure 4A, the strip 604 extends longitudinally from the proximal end 602 to the distal end 610, with a series of electrode tabs 606a, 606b, 606c, 606d extending perpendicularly to the right and two stabilizer tabs 608a, 608b extending to the left. In the example in Figure 6A, the non-conductive stabilizer tabs are not positioned between the electrode tabs when a medical device is wrapped. In that regard, the stabilizer tabs may function to stabilize the electrode assembly patch and enhance adhesion when the electrode assembly patch is attached to a part of an intravascular blood pump or other device (e.g., using thermoforming, adhesive, glue, etc.), but they do not function as separator tabs. Similar to Figure 4A, the strip 604 has a tapered section near its proximal end 602, and as a result, the strip 604 has a wider portion at its proximal end 602 that can be used to weld or join an external wire to a contact placed thereon.

[0130] Again, while the example in Figure 6A shows all electrode tabs extending to the right of strip 604 and all stabilizer tabs extending to the left of strip 604, it will be understood that any suitable arrangement may be used. For example, in some aspects of this technology, the orientation of each tab may be reversed from that shown in Figure 6A. Similarly, in some aspects of this technology, the tabs labeled 606a, 606b, and 608b may extend to the left of strip 604, respectively, and the tabs labeled 608a, 606c, and 606d may extend to the right of strip 404, respectively. Furthermore, while the exemplary electrode assembly patch 600 in Figure 6A is shown with four electrode tabs, in some aspects of this technology, the electrode assembly patch 600 may be implemented with more or fewer additional sets of electrode tabs (for example, so that the total number of electrode tabs is 2, 6, 8, 10, 12, etc.). Again, as described above, the electrode assembly patch is shown with two stabilizer tabs, but it will be understood that the electrode assembly patch may not include stabilizer tabs, or may have more or fewer tabs. Also, the position of the tabs along the longitudinal axis of the strip may differ in other embodiments.

[0131] The exemplary electrode assembly patch 600 in Figure 6A may be fitted to any suitable intravascular blood pump, and its dimensions may be customized to suit the device to which the electrode assembly patch 600 is attached. In this regard, Figure 6B shows a copy of the exemplary electrode assembly patch 600 of Figure 6A, annotated to show various features and dimensions to which the assembly may be modified to fit different intravascular blood pumps or other devices. For illustrative purposes, each of the features and dimensions shown in Figure 6B is described below using the assumption that the electrode assembly patch will be attached (e.g., thermoformed, bonded, glued, etc.) to the outer surface of the cannula of the intravascular blood pump (e.g., cannula 110 in Figure 1). It is further assumed that the cannula has a length of at least 55 mm and a diameter of approximately 14 Fr (4.67 mm). Figures 6A and 6B show the same exemplary electrode assembly patch 600, but for clarity, elements identified in Figure 6A are again not identified in Figure 6B.

[0132] Using the above assumptions, the electrode assembly patch 600 in Figure 6B may have a total length 628 of 55 mm. The proximal end of the strip may have a contact patch that is 6 mm wide 620 and 2.5 mm long 622, then tapering to a width of 3 mm 638. The tapered section may have a length 624 of 2.5 mm and a taper angle 626 of approximately 149°.

[0133] The four electrode tabs may each have a width of 3 mm, and may be arranged such that the first tab and the second tab (606a and 606b in Figure 6A) and the third tab and the fourth tab (606c and 606d in Figure 6A) are separated by a distance of 3 mm, and the second tab and the third tab (606b and 606c in Figure 6A) are separated by a distance of 10 mm. Thus, the set of four electrode tabs may have a total length of 28 mm. Again, in some aspects of this technology, it may be desirable to maximize the distance between the second tab and the third tab (606b and 606c in Figure 6A). Thus, if the dimensions of the anatomical form of the pump and / or patient allow for an increase in the distance, it may be advantageous to do so, provided that all four electrode tabs can still fit within the volume to be measured (e.g., the patient's left ventricle).

[0134] Similar to Figure 4B, the length 640 of each electrode tab can be configured such that when the tab wraps around the outside of the cannula, the end of each tab approaches the left edge of the strip but does not overlap. In this regard, assuming a cannula with a diameter of 14Fr has a circumference of approximately 14.66 mm and the strip has a width of 3 mm 638, each electrode tab may have a length 640 of 11.5 mm such that a gap of approximately 0.16 mm remains when the tab wraps around the cannula. Here again, as mentioned above, it will be understood that avoiding overlap is not essential to this technique, but it can provide advantages in certain cases.

[0135] In the examples of Figures 6A and 6B, the first stabilizer tab (608a in Figure 6A) is positioned proximal to the first electrode tab (606a in Figure 6A), and the second stabilizer tab (608b in Figure 6A) is positioned between the second electrode tab and the third electrode tab (606b and 606c in Figure 6A) to stabilize and enhance the adhesion of the electrode assembly patch in the region between the second and third electrode tabs. The stabilizer tabs in Figures 6A and 6B do not need to fit within the distance 644 between the first and second electrode tabs or between the third and fourth electrode tabs, and therefore may have a wider range of dimensions than those in Figures 4A and 4B. In this example, we assume that each stabilizer tab has a length 636 of 5 mm and a width 630 of 3 mm.

[0136] As shown in Figures 6A and 6B, each of the stabilizer tabs 608a, 608b and each of the electrode tabs 606a-606d have a curved section (e.g., 646) that they join to the strip 604. In some embodiments, rounding the corners in this manner can reduce the possibility of tearing and / or delamination of the electrode assembly patch at these joints. Any suitable profile may be used for these curved sections. For example, in some aspects of the art, the curved sections may have a constant radius (e.g., 1 mm).

[0137] Figure 7A shows a further exemplary electrode assembly patch 700 according to aspects of the present disclosure. Here again, the exemplary electrode assembly patch 700 may be configured as a multilayer strip 704 having any suitable number and configuration of layers, including configurations based on the configurations described above with respect to Figures 4C and 4D. In the example of Figure 7A, the strip 704 extends longitudinally from the proximal end 702 to the distal end 708 and has a series of electrode tabs 706a, 706b, 706c, 706d, each electrode tab extending perpendicularly to the strip 704 in both left and right directions. As above, in other embodiments, the tabs may extend at other suitable angles with respect to the strip and other tabs. As shown in the example of Figure 7A, the strip 704 may be wider in sections near the proximal end of the strip (e.g., proximal to the first electrode strip 706a), which may help weld or bond an external wire to a contact patch placed thereon.

[0138] Unlike the exemplary electrode assemblies 400 and 600 in Figures 4A and 6A, the wider portion of the strip 704 at the proximal end 702 directly contacts the first electrode strip 706a. As a result, the exemplary electrode assembly patch of 700 may be shorter overall than the exemplary electrode assemblies 400 and 600 in Figures 4A and 6A, which may be advantageous when the electrode assembly patch needs to be attached to a shorter portion of an intravascular blood pump or other device, where the wires connected to each contact patch are routed within the lumen or wall of a cannula (e.g., cannula 110 in Figure 1). In contrast, the exemplary electrode assemblies 400 and 600 in Figures 4A and 6A may be advantageous when the electrode tabs (e.g., tabs 406a–406d in Figure 4A, tabs 606a–606d in Figure 6A) need to be positioned at a greater distance from where the wires connected to each contact patch protrude from the catheter (e.g., catheter 102 in Figure 1), because the portion of the strip (e.g., strip 404 in Figure 4A, strip 604 in Figure 6A) between the proximal end (e.g., proximal end 402 in Figure 4A, proximal end 602 in Figure 6A) and the first electrode tab (e.g., electrode tab 406a in Figure 4A, electrode tab 606a in Figure 6A) may be thinner, more flexible, more durable, and / or easier to attach to the cannula than when a standard wire (e.g., wire 502) is fixed to the cannula (e.g., cannula 110 in Figure 1).

[0139] The example in Figure 7A shows that all electrode tabs extend to both the left and right sides of strip 704, but any suitable arrangement may be used. For example, in some aspects of the art, all tabs may extend to the right side only, or to the left side only. Similarly, in some aspects of the art, the tabs labeled 706a and 706b may extend to the right side of strip 704, respectively, and the tabs labeled 706c and 706d may extend to the left side of strip 704, respectively, and vice versa. Furthermore, although the exemplary electrode assembly patch 700 in Figure 7A is shown with four electrode tabs, in some aspects of the art, the electrode assembly patch 700 may be implemented with more or fewer electrode tab sets (for example, so that the total number of electrode tabs is 2, 6, 8, 10, 12, etc.).

[0140] The exemplary electrode assembly patch 700 in Figure 7A may be fitted to any suitable intravascular blood pump, and its dimensions may be customized to suit the device to which the electrode assembly patch 700 is attached. In this regard, Figure 7B shows a copy of the exemplary electrode assembly patch 700 of Figure 7A, annotated to show various features and dimensions to which the assembly may be modified to fit different intravascular blood pumps or other devices. For illustrative purposes, each of the features and dimensions shown in Figure 7B is described below using the assumption that the electrode assembly patch is configured to be attached (e.g., thermoformed, bonded, glued, etc.) to the outer surface of the cannula of the intravascular blood pump (e.g., cannula 110 in Figure 1). It is further assumed that the cannula has a length of at least 30 mm and a diameter of approximately 14 Fr (4.67 mm). Figures 7A and 7B show the same exemplary electrode assembly patch 700, but for clarity, elements identified in Figure 7A are again not identified in Figure 7B.

[0141] Using the above assumptions, the electrode assembly patch 700 in Figure 7B may have a total length 730 of 30 mm. The proximal end of the strip may have a contact patch with a width 720 of 4 mm and a length 722 of 2 mm.

[0142] The four electrode tabs may each have a width of 3 mm, and may be arranged such that the first tab and the second tab (706a and 706b in Figure 7A) and the third tab and the fourth tab (706c and 706d in Figure 7A) are separated by a distance of 3 mm, and the second tab and the third tab (706b and 706c in Figure 7A) are separated by a distance of 10 mm. Here again, in some aspects of this technology, it may be desirable to maximize the distance 728 between the second tab and the third tab (706b and 706c in Figure 7A). Therefore, if the dimensions of the anatomical form of the pump and / or patient allow for an increase in the distance 728, it may be advantageous to do so, provided that all four electrode tabs can still fit within the volume to be measured (e.g., the patient's left ventricle).

[0143] Each electrode tab may extend 5.5 mm 732 to the left and right of the strip. Here again, this distance 732 can be chosen so that the ends of each tab are close to each other but do not overlap. In this regard, assuming that a cannula with a diameter of 14 Fr has a circumference of approximately 14.66 mm and the strip has a width of 3 mm 734, each electrode tab may extend 5.5 mm 732 to the left and right such that a gap of approximately 0.66 mm remains when the tab wraps around the cannula. Here again, as mentioned above, avoiding overlap is not essential to this technique, but it will be understood that it may offer advantages in certain cases.

[0144] Although the patch is illustrated and described as having tabs in which electrodes can extend, it will be understood that the electrode assembly patch may also consist only of a strip in which electrodes extend within different regions of the strip, as shown in Figure 8. For example, as shown in Figure 8, the electrode assembly patch 800 may include four electrodes (806a-806d). In some embodiments, the strip 804 may have a uniform thickness between its proximal end 802 and distal end 808 that is greater than the thickness of the strip shown in other exemplary patches (see, for example, Figures 4A and 6A). As above, the distance between electrodes may be maintained relative to each other through the electrode assembly patch 800 and may be the same as the distance described above with respect to the electrode assembly patch having tabs. The length of the electrodes may also be the same as the electrodes extending within the electrode tabs shown in the exemplary patches above.

[0145] From the above and with reference to the various figures, those skilled in the art will understand that certain modifications can be made to this disclosure without departing from its scope. While the figures illustrate several aspects of this disclosure, it is not intended to limit it thereto, and this disclosure is intended to have the same breadth as permitted in the art, and the specification should be read in the same manner. Therefore, the above description should not be construed as a limitation, but merely as an example of certain aspects of the art.

[0146] In some embodiments, the electrode assembly patch may be configured to form at least a portion of the cannula of an intravascular blood pump. For example, in some embodiments, the electrode assembly patch may form the outer layer of the cannula of an intravascular blood pump. In such embodiments, the electrode assembly patch may wrap around a support structure, be wrapped around a support structure, or otherwise be positioned. In one embodiment, the support structure may include one or more strands or coils of a shape memory material such as nitinol. In some embodiments, the cannula may include a multilayer structure comprising a polyurethane inner layer, a layer formed from the support structure (e.g., a nitinol coil), and an outer layer formed from the electrode assembly patch. In some embodiments, the non-conductive layer of the electrode assembly patch may also include polyurethane as the non-conductive material.

[0147] Example Implementation As already explained, the technologies described herein can be implemented in a variety of ways. In this regard, the above disclosure is intended to include, but is not limited to, the systems, methods, and combinations and partial combinations thereof described in the following categories of exemplary implementations.

[0148] Category A: A1. A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and An electrode assembly patch that can be attached to an intravascular device, equipped with the necessary components. A2. An electrode assembly patch A1, wherein the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab extend in a direction away from the first side of the strip in a first direction. A3. A first stabilizing tab extends outward from the second side of the strip in a second direction opposite to the first direction, A second stabilizing tab is provided, which is separated from the first stabilizing tab and extends in a direction away from the strip in the second direction. The A2 electrode assembly patch further enhances this feature. A4. An electrode assembly patch A3, wherein the first stabilizing tab is positioned laterally between the first electrode tab and the second electrode tab. A5. An electrode assembly patch A4, wherein the second stabilizing tab is positioned laterally between the third electrode tab and the fourth electrode tab. A6. A flexible electrode assembly patch, one of A1-A5 types. A7. One of the electrode assembly patches A1 to A6, configured to have a two-dimensional structure in an unfolded state and further configured to have a three-dimensional structure in an unfolded state. A8. Electrode assembly patches A1 to A7, each of the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab, each containing an electrode extending within the tab. A9. An electrode assembly patch of A8, wherein the electrode comprises either gold or platinum, or both. A10. An electrode assembly patch A1 to A8, wherein the second tab is separated from the first tab by a first distance, the third tab is separated from the second tab by a second distance, and the fourth tab is separated from the third tab by a first distance. A11. An electrode assembly patch of A10, wherein the second distance is greater than the first distance and the third distance. A12. An electrode assembly patch of any of A3 to A11, wherein each of the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab, and each of the first stabilization tab and the second stabilization tab, extends perpendicularly to the strip. A13. An electrode assembly patch of any of A3 to A12, wherein the width of the first stabilizing tab is less than or equal to a first lateral distance between the first electrode tab and the second electrode tab, and the width of the second stabilizing tab is less than or equal to a second lateral distance between the third electrode tab and the fourth electrode tab. A14. An electrode assembly patch, one of A1 to A13, comprising four layers, each having a thickness of 5 μm.

[0149] Category B: B15. An intravascular device configured to be inserted into the patient's heart, A flexible electrode assembly patch attached to at least a portion of the intravascular device, comprising two or more electrodes configured to determine admittance and / or conductance, and A system for determining admittance or conductance, comprising the following: B16. The aforementioned flexible electrode assembly patch A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and A B15 system including [this]. B17. A system of B16, wherein the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab extend in a direction away from the first side of the strip in a first direction. B18. A first stabilizing tab extends outward from the second side of the strip in a second direction opposite to the first direction, A second stabilizing tab is provided, which is separated from the first stabilizing tab and extends in a direction away from the strip in the second direction. The B17 system is further equipped with these features. B19. The flexible electrode assembly patch comprises a strip having a proximal end and a distal end, in the systems of B15-B18. B20. A controller electrically connected to the electrode assembly patch, A current source and Memory and The memory is coupled to and AC current is supplied to the electrodes of the first electrode tab and the fourth electrode tab. The voltage passing through the electrodes of the second electrode tab and the third electrode tab is measured, and The admittance or conductance is determined based on the measured voltages of the second and third tabs. One or more processors configured as such A controller equipped with A system from B15 to B19 that further includes these features.

[0150] Category C: C21. Intravascular devices configured to be inserted into the patient's heart; and An electrode assembly patch attached to at least a portion of the intravascular device, A first non-conductive layer configured to adhere to the portion of the intravascular device, A second layer having one or more wires, A third non-conductive layer configured to electrically insulate one or more of the aforementioned wires, A fourth layer containing a 100 electrode and Electrode assembly patch including a multilayer structure having A system for determining admittance or conductance, comprising the following: C22. The first nonconductive layer, Polymer material configured to be bonded, joined, and / or thermoformed to the portion of the intravascular device A C21 system that can be formed from. C23. A C21 or C22 system in which each of the one or more wires is separated by a non-conductive material. C24. A system of any of C21 to C23, wherein one or more of the aforementioned wires are formed from a conductive material. C25. A C24 system in which the conductive material includes platinum, gold, silver, and / or copper. C26. A system of any of C21 to C25, wherein one or more electrodes in the fourth layer are at least partially exposed. C27. A system C21 to C26 wherein the multilayer structure includes four sandwich layers. C28. A system of any of C21 to C27, wherein the layers are bonded, joined, and / or thermoformed to one another. C29. The electrode assembly patch, A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and A system including any of the C21-C28 systems. C30. A system of C29, wherein the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab extend in a direction away from the first side of the strip in a first direction. C31. A first stabilizing tab extends outward from the second side of the strip in a second direction opposite to the first direction, A second stabilizing tab is provided, which is separated from the first stabilizing tab and extends in a direction away from the strip in the second direction. The C30 system is further equipped with these features. C32. The electrode assembly patch comprises any of the C31-C31 systems, wherein the electrode assembly patch includes a strip having a proximal end and a distal end. C33. A controller electrically connected to the electrode assembly patch, A current source and Memory and The memory is coupled to and AC current is supplied to the electrodes of the first electrode tab and the fourth electrode tab. The voltage passing through the electrodes of the second electrode tab and the third electrode tab is measured, and The admittance or conductance is determined based on the measured voltages of the second and third tabs. One or more processors configured as such A controller equipped with The C16 system further incorporates these features.

[0151] Category D: D34. A method for forming a system for determining admittance or conductance, The steps of wrapping and / or enclosing with a flexible electrode assembly patch at least a portion of an intravascular device configured to be inserted into the patient's heart, and Steps to attach the flexible electrode assembly patch to the portion of the intravascular device. Methods that include... D35. The method of D34, wherein the attachment step includes thermoforming the flexible electrode assembly patch onto the portion of the intravascular device. D36. The method of D34 or D35 wherein the flexible electrode assembly patch includes a multilayer structure. D37. The aforementioned flexible electrode assembly patch A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and Any of the methods from D34 to D36, including the above. D38. The D37 method, wherein the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab extend in a direction away from the first side of the strip in a first direction. D39. The aforementioned flexible electrode assembly patch A first stabilizing tab extends outward from the second side of the strip in a second direction opposite to the first direction, A second stabilizing tab is provided, which is separated from the first stabilizing tab and extends in a direction away from the strip in the second direction. The D38 method further enhances this. D40. Before the flexible electrode assembly patch is wrapped around the intravascular device and / or encloses the intravascular device, the flexible electrode assembly patch includes a two-dimensional configuration, in any of the methods D34 to D39.

[0152] Category E: E41. An intravascular blood pump configured to deliver blood from a blood inlet to a blood outlet through a cannula; An electrode assembly coupled to at least a portion of the cannula, A strip extending from the proximal end to the distal end, A first tab extending perpendicularly away from the strip, having electrodes configured to supply current to the surrounding fluid, A second tab is positioned distal to the first tab and extends perpendicularly away from the strip, and is configured to measure the voltage in the ambient fluid. A third tab is positioned distal to the second tab and extends perpendicularly away from the strip, and is configured to measure the voltage in the ambient fluid. A fourth tab positioned distal to the third tab and extending perpendicularly away from the strip, the fourth tab being configured to supply current to the ambient fluid and An electrode assembly comprising; A controller electrically connected to the electrode assembly, A current source and Memory and The memory is coupled to and AC current is supplied to the electrodes of the first tab and the fourth tab, The voltage passing through the electrodes of the second tab and the third tab is measured, and The admittance or conductance is determined based on the measured voltages of the second and third tabs. One or more processors configured as such A controller equipped with An intravascular blood pump system equipped with this system. E42. System E41, wherein the second tab is distal to the first tab by a first distance, the third tab is distal to the second tab by a second distance, and the fourth tab is distal to the third tab by a first distance. E43. The electrode assembly, A fifth tab is positioned distal to the first tab and proximal to the second tab, and extends in a direction perpendicular to the strip, opposite to the first and second tabs, A sixth tab is positioned distal to the third tab and proximal to the fourth tab, and extends in a direction perpendicular to the strip, opposite to the third and fourth tabs. The E42 system is further equipped with these features. E44. A system of E43 configured such that the width of the fifth tab and the width of the sixth tab are less than or equal to the first distance. E45. A system of E44 in which the aforementioned first distance is 3 mm. E46. A system of E45, wherein the width of the fifth tab and the width of the sixth tab are 2.5 mm. E47. The E45 system, wherein the second distance is 10 mm. E48. The electrode assembly, A fifth tab is positioned proximal to the first tab and extends in a direction opposite to the first and second tabs, perpendicular to the strip, A sixth tab is positioned distal to the second tab and proximal to the third tab, and extends in a direction perpendicular to the strip, opposite to the third and fourth tabs. The E42 system is further equipped with these features. E49. The E48 system, wherein the aforementioned first distance is 3 mm. E50. A system of E49 in which the width of the fifth tab and the width of the sixth tab are 3 mm. E51. The E49 system, wherein the second distance is 10 mm. E52. A system of E41 in which the electrode assembly is configured to be flexible. E53. A system of E41 in which the electrodes of the first tab, the second tab, the third tab, and the fourth tab include either gold or platinum, or both. E54. The E41 system, wherein the electrode assembly comprises four layers, each layer having a thickness of 5 μm. E55. The E41 system, wherein the current source is configured to supply substantially constant alternating currents of 10 μA and 100 μA at 20 kHz.

[0153] Category F: F56. An intravascular device configured to be inserted into the patient's heart; An electrode assembly coupled to at least a portion of the intravascular device, A strip extending from the proximal end to the distal end, A first tab extending perpendicularly away from the strip, having electrodes configured to supply current to the surrounding fluid, A second tab is positioned distal to the first tab and extends perpendicularly away from the strip, and is configured to measure the voltage in the ambient fluid. A third tab is positioned distal to the second tab and extends perpendicularly away from the strip, and is configured to measure the voltage in the ambient fluid. A fourth tab positioned distal to the third tab and extending perpendicularly away from the strip, the fourth tab being configured to supply current to the ambient fluid and An electrode assembly comprising; A controller electrically connected to the electrode assembly, A current source and Memory and The memory is coupled to and AC current is supplied to the electrodes of the first tab and the fourth tab, The voltage passing through the electrodes of the second tab and the third tab is measured, and The admittance or conductance is determined based on the measured voltages of the second and third tabs. One or more processors configured as such A controller equipped with A system for determining admittance or conductance, comprising the following: F57. A system of F56, wherein the second tab is distal to the first tab by a first distance, the third tab is distal to the second tab by a second distance, and the fourth tab is distal to the third tab by a first distance. F58. The electrode assembly, A fifth tab is positioned distal to the first tab and proximal to the second tab, and extends in a direction perpendicular to the strip, opposite to the first and second tabs, A sixth tab is positioned distal to the third tab and proximal to the fourth tab, and extends in a direction perpendicular to the strip, opposite to the third and fourth tabs. The F57 system is further equipped with these features. F59. A system of F58 configured such that the width of the fifth tab and the width of the sixth tab are less than or equal to the first distance. F60. A system of the F59, wherein the aforementioned first distance is 3 mm. F61. A system of F60 in which the width of the fifth tab and the width of the sixth tab are 2.5 mm. F62. The F60 system, wherein the second distance is 10 mm. F63. The electrode assembly, A fifth tab is positioned proximal to the first tab and extends in a direction opposite to the first and second tabs, perpendicular to the strip, A sixth tab is positioned distal to the second tab and proximal to the third tab, and extends in a direction perpendicular to the strip, opposite to the third and fourth tabs. The F57 system is further equipped with these features. F64. The F63 system, wherein the aforementioned first distance is 3 mm. F65. A system of F64 in which the width of the fifth tab and the width of the sixth tab are 3 mm. F66. The F64 system, where the second distance is 10 mm. F67. A system of F56 in which the electrode assembly is configured to be flexible. F68. A system of F56 in which the electrodes of the first tab, the second tab, the third tab, and the fourth tab include either gold or platinum, or both. F69. The F56 system, wherein the electrode assembly comprises four layers, each layer having a thickness of 5 μm. F70. The F56 system, wherein the current source is configured to supply substantially constant alternating currents of 10 μA and 100 μA at 20 kHz.

Claims

1. A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and An electrode assembly patch that can be attached to an intravascular device, equipped with the necessary components.

2. The electrode assembly patch according to claim 1, wherein the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab extend in a direction away from the first side of the strip in a first direction.

3. A first stabilizing tab extends outward from the second side of the strip in a second direction opposite to the first direction, A second stabilizing tab is provided, which is separated from the first stabilizing tab and extends in a direction away from the strip in the second direction. The electrode assembly patch according to claim 2, further comprising:

4. The electrode assembly patch according to claim 3, wherein the first stabilizing tab is positioned laterally between the first electrode tab and the second electrode tab.

5. The electrode assembly patch according to claim 4, wherein the second stabilizing tab is positioned laterally between the third electrode tab and the fourth electrode tab.

6. An electrode assembly patch according to any one of claims 1 to 5, configured to be flexible.

7. An electrode assembly patch according to any one of claims 1 to 6, configured to have a two-dimensional structure in an unfolded state and further configured to have a three-dimensional structure in an unfolded state.

8. The electrode assembly patch according to any one of claims 1 to 7, wherein each of the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab includes an electrode extending within the tab.

9. The electrode assembly patch according to claim 8, wherein the electrode comprises gold or platinum, or both.

10. The electrode assembly patch according to any one of claims 1 to 8, wherein the second tab is separated from the first tab by a first distance, the third tab is separated from the second tab by a second distance, and the fourth tab is separated from the third tab by a first distance.

11. The electrode assembly patch according to claim 10, wherein the second distance is greater than the first distance and the third distance.

12. An electrode assembly patch according to any one of claims 3 to 11, wherein each of the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab, and each of the first stabilization tab and the second stabilization tab, extend perpendicularly to the strip.

13. The electrode assembly patch according to any one of claims 3 to 12, wherein the width of the first stabilizing tab is less than or equal to a first lateral distance between the first electrode tab and the second electrode tab, and the width of the second stabilizing tab is less than or equal to a second lateral distance between the third electrode tab and the fourth electrode tab.

14. The electrode assembly patch according to any one of claims 1 to 13, wherein the patch comprises four layers, each layer having a thickness of 5 μm.

15. An intravascular device configured to be inserted into the patient's heart, A flexible electrode assembly patch attached to at least a portion of the intravascular device, comprising two or more electrodes configured to determine admittance and / or conductance, and A system for determining admittance or conductance, comprising the following:

16. The aforementioned flexible electrode assembly patch A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and The system according to claim 15, including the system described in claim 15.

17. The system according to claim 16, wherein the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab extend in a direction away from the first side of the strip in a first direction.

18. A first stabilizing tab extends outward from the second side of the strip in a second direction opposite to the first direction, A second stabilizing tab is provided, which is separated from the first stabilizing tab and extends in a direction away from the strip in the second direction. The system according to claim 17, further comprising:

19. The system according to any one of claims 15 to 18, wherein the flexible electrode assembly patch includes a strip having a proximal end and a distal end.

20. A controller electrically connected to the electrode assembly patch, A current source and Memory and The memory is coupled to and AC current is supplied to the electrodes of the first electrode tab and the fourth electrode tab. The voltage passing through the electrodes of the second electrode tab and the third electrode tab is measured, and The admittance or conductance is determined based on the measured voltages of the second and third tabs. One or more processors configured as such A controller equipped with The system according to any one of claims 15 to 19, further comprising the above.

21. Intravascular devices configured to be inserted into the patient's heart; and An electrode assembly patch attached to at least a portion of the intravascular device, A first non-conductive layer configured to adhere to the portion of the intravascular device, A second layer having one or more wires, A third non-conductive layer configured to electrically insulate one or more of the aforementioned wires, A fourth layer containing a 100 electrode and Electrode assembly patch including a multilayer structure having A system for determining admittance or conductance, comprising the following:

22. The first nonconductive layer, Polymer material configured to be bonded, joined, and / or thermoformed to the portion of the intravascular device The system according to claim 21, which may be formed from the above.

23. The system according to claim 21 or 22, wherein each of the one or more wires is separated by a non-conductive material.

24. The system according to any one of claims 21 to 23, wherein the one or more wires are formed from a conductive material.

25. The system according to claim 24, wherein the conductive material comprises platinum, gold, silver, and / or copper.

26. The system according to any one of claims 21 to 25, wherein one or more electrodes in the fourth layer are at least partially exposed.

27. The system according to any one of claims 21 to 26, wherein the multilayer structure comprises four sandwich layers.

28. The system according to any one of claims 21 to 27, wherein the layers are bonded, joined, and / or thermoformed to one another.

29. The electrode assembly patch, A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and A system according to any one of claims 21 to 28, including the system described in any one of claims 21 to 28.

30. The system according to claim 29, wherein the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab extend in a direction away from the first side of the strip in a first direction.

31. A first stabilizing tab extends outward from the second side of the strip in a second direction opposite to the first direction, A second stabilizing tab is provided, which is separated from the first stabilizing tab and extends in a direction away from the strip in the second direction. The system according to claim 30, further comprising:

32. The system according to any one of claims 31 to 31, wherein the electrode assembly patch includes a strip having a proximal end and a distal end.

33. A controller electrically connected to the electrode assembly patch, A current source and Memory and The memory is coupled to and AC current is supplied to the electrodes of the first electrode tab and the fourth electrode tab. The voltage passing through the electrodes of the second electrode tab and the third electrode tab is measured, and The admittance or conductance is determined based on the measured voltages of the second and third tabs. One or more processors configured as such A controller equipped with The system according to claim 16, further comprising:

34. A method for forming a system for determining admittance or conductance, The steps of wrapping and / or enclosing with a flexible electrode assembly patch at least a portion of an intravascular device configured to be inserted into the patient's heart, and Steps to attach the flexible electrode assembly patch to the portion of the intravascular device. Methods that include...

35. The method according to claim 34, wherein the attachment step includes thermoforming the flexible electrode assembly patch to the portion of the intravascular device.

36. The method according to claim 34 or 35, wherein the flexible electrode assembly patch includes a multilayer structure.

37. The aforementioned flexible electrode assembly patch A strip extending from the proximal end to the distal end, A first electrode tab extending outward from the strip, configured to supply current to the surrounding fluid, A second electrode tab, separated from the first electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A third electrode tab, separated from the second electrode tab, extending outward from the strip and configured to measure the voltage in the ambient fluid, A fourth electrode tab, separated from the third tab, extending outward from the strip and configured to supply current to the surrounding fluid, and The method according to any one of claims 34 to 36, including the method described in any one of claims 34 to 36.

38. The method according to claim 37, wherein the first electrode tab, the second electrode tab, the third electrode tab, and the fourth electrode tab extend in a direction away from the first side of the strip in a first direction.

39. The aforementioned flexible electrode assembly patch A first stabilizing tab extends outward from the second side of the strip in a second direction opposite to the first direction, A second stabilizing tab is provided, which is separated from the first stabilizing tab and extends in a direction away from the strip in the second direction. The method according to claim 38, further comprising:

40. The method according to any one of claims 34 to 39, wherein the flexible electrode assembly patch includes a two-dimensional configuration before it is wrapped around and / or encloses the intravascular device.

41. An intravascular blood pump, configured to deliver blood from a blood inlet to a blood outlet through a cannula; An electrode assembly coupled to at least a portion of the cannula, A strip extending from the proximal end to the distal end, A first tab extending perpendicularly away from the strip, having electrodes configured to supply current to the surrounding fluid, A second tab is positioned distal to the first tab and extends perpendicularly away from the strip, and is configured to measure the voltage in the ambient fluid. A third tab is positioned distal to the second tab and extends perpendicularly away from the strip, and is configured to measure the voltage in the ambient fluid. A fourth tab positioned distal to the third tab and extending perpendicularly away from the strip, the fourth tab being configured to supply current to the ambient fluid and An electrode assembly comprising; A controller electrically connected to the electrode assembly, A current source and Memory and The memory is coupled to and AC current is supplied to the electrodes of the first tab and the fourth tab, The voltage passing through the electrodes of the second tab and the third tab is measured, and The admittance or conductance is determined based on the measured voltages of the second and third tabs. One or more processors configured as such A controller equipped with An intravascular blood pump system equipped with this system.

42. The system according to claim 41, wherein the second tab is distal to the first tab by a first distance, the third tab is distal to the second tab by a second distance, and the fourth tab is distal to the third tab by a first distance.

43. The electrode assembly, A fifth tab is positioned distal to the first tab and proximal to the second tab, and extends in a direction perpendicular to the strip, opposite to the first and second tabs, A sixth tab is positioned distal to the third tab and proximal to the fourth tab, and extends in a direction perpendicular to the strip, opposite to the third and fourth tabs. The system according to claim 42, further comprising:

44. The system according to claim 43, wherein the width of the fifth tab and the width of the sixth tab are configured to be less than or equal to the first distance.

45. The system according to claim 44, wherein the first distance is 3 mm.

46. The system according to claim 45, wherein the width of the fifth tab and the width of the sixth tab are 2.5 mm.

47. The system according to claim 45, wherein the second distance is 10 mm.

48. The electrode assembly, A fifth tab is positioned proximal to the first tab and extends in a direction opposite to the first and second tabs, perpendicular to the strip, A sixth tab is positioned distal to the second tab and proximal to the third tab, and extends in a direction perpendicular to the strip, opposite to the third and fourth tabs. The system according to claim 42, further comprising:

49. The system according to claim 48, wherein the first distance is 3 mm.

50. The system according to claim 49, wherein the width of the fifth tab and the width of the sixth tab are 3 mm.

51. The system according to claim 49, wherein the second distance is 10 mm.

52. The system according to claim 41, wherein the electrode assembly is configured to be flexible.

53. The system according to claim 41, wherein the electrodes of the first tab, the second tab, the third tab, and the fourth tab include gold or platinum, or both.

54. The system according to claim 41, wherein the electrode assembly comprises four layers, each layer having a thickness of 5 μm.

55. The system according to claim 41, wherein the current source is configured to supply substantially constant alternating currents of 10 μA and 100 μA at 20 kHz.

56. An intravascular device configured to be inserted into the patient's heart; An electrode assembly coupled to at least a portion of the intravascular device, A strip extending from the proximal end to the distal end, A first tab extending perpendicularly away from the strip, having electrodes configured to supply current to the surrounding fluid, A second tab is positioned distal to the first tab and extends perpendicularly away from the strip, and is configured to measure the voltage in the ambient fluid. A third tab is positioned distal to the second tab and extends perpendicularly away from the strip, and is configured to measure the voltage in the ambient fluid. A fourth tab positioned distal to the third tab and extending perpendicularly away from the strip, the fourth tab being configured to supply current to the ambient fluid and An electrode assembly comprising; A controller electrically connected to the electrode assembly, A current source and Memory and The memory is coupled to and AC current is supplied to the electrodes of the first tab and the fourth tab, The voltage passing through the electrodes of the second tab and the third tab is measured, and The admittance or conductance is determined based on the measured voltages of the second and third tabs. One or more processors configured as such A controller equipped with A system for determining admittance or conductance, comprising the following:

57. The system according to claim 56, wherein the second tab is distal to the first tab by a first distance, the third tab is distal to the second tab by a second distance, and the fourth tab is distal to the third tab by a first distance.

58. The electrode assembly, A fifth tab is positioned distal to the first tab and proximal to the second tab, and extends in a direction perpendicular to the strip, opposite to the first and second tabs, A sixth tab is positioned distal to the third tab and proximal to the fourth tab, and extends in a direction perpendicular to the strip, opposite to the third and fourth tabs. The system according to claim 57, further comprising:

59. The system according to claim 58, wherein the width of the fifth tab and the width of the sixth tab are configured to be less than or equal to the first distance.

60. The system according to claim 59, wherein the first distance is 3 mm.

61. The system according to claim 60, wherein the width of the fifth tab and the width of the sixth tab are 2.5 mm.

62. The system according to claim 60, wherein the second distance is 10 mm.

63. The electrode assembly, A fifth tab is positioned proximal to the first tab and extends in a direction opposite to the first and second tabs, perpendicular to the strip, A sixth tab is positioned distal to the second tab and proximal to the third tab, and extends in a direction perpendicular to the strip, opposite to the third and fourth tabs. The system according to claim 57, further comprising:

64. The system according to claim 63, wherein the first distance is 3 mm.

65. The system according to claim 64, wherein the width of the fifth tab and the width of the sixth tab are 3 mm.

66. The system according to claim 64, wherein the second distance is 10 mm.

67. The system according to claim 56, wherein the electrode assembly is configured to be flexible.

68. The system according to claim 56, wherein the electrodes of the first tab, the second tab, the third tab, and the fourth tab include gold or platinum, or both.

69. The system according to claim 56, wherein the electrode assembly comprises four layers, each layer having a thickness of 5 μm.

70. The system according to claim 56, wherein the current source is configured to supply substantially constant alternating currents of 10 μA and 100 μA at 20 kHz.

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