Systems and methods for treating cardiovascular impairment

Abstract

A method for implanting a device into a heart of a mammal may include a fluid conduit leading from an atrium into an aorta. The fluid conduit may also include a pump and a sensor in the atrium for feedback to the controller for operation of the pump. The outflow of the fluid contact may include a diffuser or fairing for managing the type and direction of flow into the aorta.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application No. 63 / 489,607, filed on March 10, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present disclosure relates to a support system and a method of performing treatment using the support system. Background Art

[0003] Heart failure can affect the heart's ability to provide adequate blood flow to the body's organs. Various conditions, such as coronary artery disease, scar tissue from a myocardial infarction, high blood pressure, and heart valve disease, can contribute to congestive heart failure. Drug interventions can dilate blood vessels and / or lower blood pressure to allow blood to flow more easily and the heart to pump more efficiently. If the damage to the heart is extensive, surgical or clinical intervention may be required. Summary of the Invention

[0004] In one aspect, a method for implanting a device into the heart of a mammal may include inserting a fluid conduit having an inflow portion and an outflow portion into a location in the cardiovascular system of the mammal, wherein the inflow portion is located within an atrium of the heart of the mammal and the outflow portion is located within a portion of the aorta of the cardiovascular system of the mammal, and the fluid conduit passes from the atrium into the aorta.

[0005] In another aspect, a system for improving blood flow in a mammal may include a fluid conduit having an inflow portion and an outflow portion, wherein the inflow portion is adapted to be positioned within an atrium of the heart of the mammal and the outflow portion is adapted to be positioned within a portion of an aorta of the cardiovascular system of the mammal, and the fluid conduit passes from the atrium into the aorta.

[0006] In some cases, the method may include anchoring the fluid conduit in the atrium such that the outflow portion enters the aorta downstream.

[0007] In some cases, the fluid conduit can be configured to be anchored in the atrium so that the outflow portion enters the aorta downstream.

[0008] In some cases, the method may include positioning the fluid conduit in the left atrium.

[0009] In some cases, the fluid conduit can be configured to be positioned in the left atrium.

[0010] In some cases, positioning the fluid conduit in the left atrium can include forming a vector path from a point on the atrial septum to the descending aorta.

[0011] In some cases, the fluid conduit can be configured to be positioned in the left atrium to form a vector path between a point on the atrial septum and the descending aorta.

[0012] In some cases, positioning the fluid conduit in the left atrium can include directing the outflow portion downstream into the descending aorta.

[0013] In some cases, the fluid conduit can be configured to be positioned in the left atrium including directing the outflow downstream into the descending aorta.

[0014] In some cases, the fluid conduits may be positioned for optimal cleaning.

[0015] In some cases, the method may include maintaining pressure in the left atrium at an optimal level for a given pathophysiology.

[0016] In some cases, the method may include providing pressure in the left atrium as feedback to a controller for the fluid conduit.

[0017] In some cases, the outflow portion may include a diffuser.

[0018] In some cases, the outflow portion may include a flow deflector.

[0019] In some cases, the fluid conduit may include a cage that is used to prevent contact with the wall of the left atrium to minimize thrombus formation and ingestion of thrombus into the pump.

[0020] In some cases, the fluid conduit may be configured to supply a diffuse fluid flow from the outflow portion.

[0021] In some cases, the fluid conduit can be configured to supply a diverging, spiraling fluid flow from the outflow portion.

[0022] In some cases, the fluid conduit can be configured to supply a fluid flow from the outflow portion at a velocity of less than 3.0 m / s, less than 2.8 m / s, less than 2.6 m / s, less than 2.4 m / s, less than 2.2 m / s, less than 2.0 m / s, less than 1.8 m / s, less than 1.6 m / s, less than 1.4 m / s, less than 1.2 m / s, or less than 1.0 m / s.

[0023] In some cases, the fluid conduit can be configured to provide a wall shear stress of less than 4500 dynes / cm from the outflow portion. 2 , less than 4000 dynes / cm 2 , less than 3500 dynes / cm 2 , less than 3000 dynes / cm 2 , less than 2500 dynes / 2 or less than 2000 dynes / cm2 of fluid flow.

[0024] In some cases, the fluid conduit can be configured to supply a fluid flow from the outflow portion at a rate of less than 10 L / min, less than 8 L / min, less than 6 L / min, less than 4 L / min, less than 3 L / min, less than 2 L / min, or less than 1 L / min.

[0025] In some cases, the fluid conduit can be configured to supply a fluid flow from the outflow portion at a flow rate greater than 0.30 L / min, greater than 0.40 L / min, greater than 0.50 L / min, greater than 0.60 L / min, greater than 0.70 L / min, or greater than 0.80 L / min.

[0026] In some cases, the system can be configured to maintain pressure in the left atrium at an optimal level for a given pathophysiology.

[0027] In some cases, the fluid conduit may include a pump.

[0028] In some cases, the pump may include a tubular core.

[0029] In certain instances, the portion of the aorta may be the descending aorta.

[0030] In some cases, the system can include a pressure sensor and a controller for the fluid conduit. The pressure sensor can be configured to provide the pressure in the left atrium as feedback to the controller.

[0031] The details of one or more embodiments of the disclosure are set forth in the accompanying drawings and the description below. Other aspects, features, and advantages will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a schematic diagram of the support system.

[0033] Figures 2A-2C is a schematic diagram of the pump supporting the system.

[0034] Figures 3A-3D Schematic and cross-sectional views of the pump supporting the system as viewed from various sides.

[0035] Figure 4 is a schematic diagram of the pump location in the support system.

[0036] Figure 5 is a schematic diagram of the pump positioned in the atrium.

[0037] Figure 6 is a schematic diagram showing the flow from the pump into the spiral in the downstream portion of the aorta.

[0038] Figure 7 is a schematic diagram of a fluid conduit with a supporting system of sensors.

[0039] Figures 8A-8B is a schematic diagram showing the effect of catheter shape on fluid dynamics.

[0040] Like reference numerals in the various drawings denote like elements. DETAILED DESCRIPTION

[0041] Exemplary configurations will now be described more fully with reference to the accompanying drawings. The exemplary configurations are provided so that the present disclosure will be thorough and fully convey the scope of the present disclosure to those of ordinary skill in the art. Specific details, such as examples of specific components, devices, and methods, are set forth to provide a full understanding of the configurations of the present disclosure. It will be apparent to those of ordinary skill in the art that specific details need not be employed, that the exemplary configurations can be embodied in many different forms, and that the specific details and exemplary configurations should not be construed as limiting the scope of the present disclosure.

[0042] The terms used herein are only used to describe the purpose of specific exemplary configurations and are not intended to be restrictive. As used herein, unless the context clearly indicates otherwise, the singular articles "a", "an" and "the" may also be intended to include plural forms. The terms "comprises", "comprising", "including" and "having" are inclusive and therefore specify the presence of features, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components and / or groups thereof. Unless specifically determined to be the order of execution, the method steps, processes and operations described herein should not be interpreted as necessarily requiring them to be performed in the specific order discussed or shown. Additional or alternative steps may be adopted.

[0043] When an element or layer is referred to as being "on top of," "engaged to," "connected to," "attached to," or "coupled to" another element or layer, it may be directly on, engaged, connected, attached to, or coupled to the other element or layer, or there may be intermediate elements or layers. In contrast, when an element is referred to as being "directly on top of," "directly engaged to," "directly connected to," "directly attached to," or "directly coupled to" another element or layer, there may be no intermediate elements or layers. Other terms used to describe the relationship between elements should be interpreted in the same manner (e.g., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the relevant listed items.

[0044] The terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or sections in this article. These elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply an order or sequence. Therefore, without departing from the teaching of the exemplary configuration, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section.

[0045] Described herein are systems and methods for assisting circulation through the atria of a mammalian heart. For example, systems and methods for permanently or temporarily improving blood flow performance in the atria may include assisting blood flow through the left atrium to the aorta. In certain embodiments, a pump may assist blood flow from the left atrium to the descending portion of the aorta.

[0046] Importantly, a percutaneously placed pump can be placed toward the descending aorta rather than toward the ascending aorta. In order to achieve a therapeutic effect, it is important to minimize damage to the aortic intima. Additionally, it is important to design the pump so that it operates only within a safe operating window. In doing so, the atrial system can improve the quality of life of individuals in various states of heart failure or other compromised cardiac conditions, which can benefit from enhanced blood flow from the atria to the descending aorta. For example, the pump can be a percutaneous pump (as described herein) or a surgically supported pump.

[0047] Generally, one aspect of the systems and methods described herein is to provide a support system for improving blood flow in a mammal. The support system can be an atrioventricular support system. For example, the support system can decompress the heart and assist systemic blood flow. The support system can include a fluid conduit. The fluid conduit can include a fluid conduit having an inflow portion and an outflow portion. The inflow portion can be adapted to be positioned within an atrium of a mammal's heart. The outflow portion can be adapted to be positioned within a portion of an aorta of a mammal's cardiovascular system. For example, the fluid conduit can pass from the atrium into the aorta. Reference Figure 1 , the fluid conduit 10 can pass from the atrium 12 to the aorta 14.

[0048] The connection between the atrium and the aorta can be achieved using a connector. The connector can have a proximal region, a distal region, and an intermediate region between the proximal region and the distal region. When viewed from the proximal end or the distal end, the intermediate region of the catheter can define an inner cavity. The proximal region and the distal region can be configured to fix the connector in the cardiovascular system. In some cases, the proximal region and the distal region can include a covering. The inner cavity defined by the intermediate region of the catheter can be supported by a tubular core, which can include, for example, a septum or a valve. The size of the catheter can be adapted to allow a needle or dilator to pass through the intermediate region via the inner cavity, and then allow the catheter and needle to be inserted into a delivery sheath for placement in the cardiovascular system.

[0049] Any suitable material can be used to construct the connector or regions of the connector. For example, the connector can be constructed as a single piece or as multiple pieces (e.g., having separate proximal and distal regions). In some cases, the connector can be constructed from a compressible, expandable, or malleable material (e.g., a balloon or shape memory alloy (nickel titanium (Nitinol))). The construction material can allow the proximal and distal regions of the catheter to deform or compress within the delivery sheath, but regain their original shape (e.g., a lip, edge, or disc) when the sheath is withdrawn. After the expandable catheter is positioned, the expandable region can be filled with any suitable material for providing long-term stability (e.g., a polymer capable of cross-linking, thermosetting, or hardening). In some cases, the connector can be constructed from a magnetic or paramagnetic material (e.g., to fix cardiovascular The tubular core may be constructed of any material that will support the intermediate region (e.g., polymer and / or metal). The septum or valve within the tubular core may be configured to prevent or control blood flow. In some cases, the septum may be adapted to be punctured to allow blood flow (e.g., after pump placement). Examples of connectors are described, for example, in U.S. Patent No. 10,137,229, which is incorporated herein by reference in its entirety.

[0050] In certain embodiments, the catheter can include a connector. The catheter can be constructed of an expandable or ductile material. The ductile material can be nitinol. The fluid conduit can have a proximal region and a distal region, each of which can be independently adjustable.

[0051] In certain embodiments, the fluid conduit can include an intermediate region. The intermediate region can include a pump having a tubular core. The tubular core of the conduit can include a diaphragm or a valve.

[0052] In certain embodiments, the fluid conduit may include a pump. Figure 2A 3A-D, the fluid conduit 10 may include a pump having a control line 20 and a controller 200 connected to the body 30, which are schematically shown in FIG2 and also referred to elsewhere herein when describing its function. The control line 20 may be a percutaneous lead from an externally worn motor controller and rechargeable battery system (which, for some embodiments, collectively form the controller 200). In some embodiments, the control line 20 is coupled to the pump from the external system component via the subclavian artery. Alternatively, for some embodiments, an implantable battery and controller (collectively forming the controller 200) may be used, which are powered via transcutaneous electron transfer (TET).

[0053] The body 30 may be a tubular core. The body 30 may include one or more inflow portions 40. The pump may have an outflow portion 50. Figure 2A -C and 3A-D, the fluid conduit 10 passes from the atrium to the aorta at the tissue interface 60. The outflow of the fluid conduit 10 may include a diffuser 75 and / or a flow shield 70.

[0054] The diffuser 75 can be a fitting from the outflow 50 that disrupts the flow of fluid from the outflow 50. In some embodiments, the diffuser 75 is a fixed vane within the flow path of the blood through and out of the outflow 50. The disruption caused by the diffuser 75 can create turbulent and non-laminar flow in the blood and can be shaped to create / maintain a spiraling flow.

[0055] In some embodiments, the shroud 70 changes the axial longitudinal flow output from the outflow portion 50 aligned with the longitudinal axis of the body 30 by an angle (i.e., greater than zero degrees and less than ninety degrees) relative to the longitudinal axis of the body 30. The shroud 70 may include extended sides oriented toward the center of the longitudinal axis of the body 30 to extend in the longitudinal direction past and beyond opposite sides of the shroud 70. The resulting orifice of the shroud 70 may have a shape such as Figure 3B and 3DThe non-circular or teardrop shape is shown and is not formed in a transverse plane relative to the longitudinal axis at the distal end of the body 30. As shown, the flow director can thus redirect flow from the outflow to reduce the impact of the flow on the tissue of the aorta. In Figure 8B In the case of the fluid conduit 10 having a flow director 70 (e.g., as shown in Figures 3A-3D The flow from the fluid conduit 10 having a flow director 70 (e.g., as shown in Figure 8A The flow director or diffuser can cause the fluid flow pattern to be directed downstream into the descending portion of the aorta.

[0056] In certain embodiments, the fluid conduit can be configured to be positioned in the left atrium, as shown in the example of Figure 1

[0057] In certain embodiments, the portion of the aorta can be the descending portion of the aorta.

[0058] In certain embodiments, as shown in Figure 1 The fluid conduit 10 can be disposed along a vector path 104 between the fossa ovalis 102 on the atrial septum 100 to a place where the aorta 14 is descending and is passing externally to the left atrium 12 in closest proximity. The point on the atrial septum 100 defining the origin of the vector path 104 can be at or near the fossa ovalis 102. The fluid conduit 10 can be oriented to follow the vector path 104 within the atrium 12 and then be directed downstream into the descending portion of the aorta 14. The vector path 104 can be a limit of the angular orientation of the fluid conduit 10 relative to the predefined vector range (e.g., up to a 5 degree difference, an 8 degree difference, or a 10 degree difference from the ideal orientation defined by the vector path 104) as the fluid conduit 10 travels along the predefined vector range to the descending aorta 14. The orientation of the outflow of the fluid conduit is used to control the direction and nature of the flow that is most tolerable for patient safety and / or hemocompatibility and / or to minimize damage to the inner surface of the aorta. Such a location and orientation can reduce complex physiological factors, including thrombosis.

[0059] In certain cases, the systems and methods protect the aortic wall. In certain cases, the systems can include structures to reduce physical contact with the aortic wall. In certain cases, the methods can include generating a fluid flow pattern that reduces damage to the aortic wall.

[0060] In certain embodiments, the fluid conduit can be configured to be anchored in the atrium such that the outflow enters downstream into the aorta. For example, as shown in Figure 5 ​As shown, the fluid conduit 10 can be secured in the wall 24 of the atrium 12 via a connector 22 such that the fluid conduit 10 extends into the downstream portion of the aorta 14. The fluid conduit 10 can include a cage 16 that can position the fluid conduit 10 in the atrium 12 and prevent contact with the atrium wall 24 to prevent occlusion, minimize thrombosis, and / or prevent ingestion of thrombi into the pump. The cage 16 can define an open structure having a diameter larger than the outer diameter of the fluid conduit 10, such as a shaped wire and / or mesh.

[0061] The fluid conduit can provide a diffused fluid outflow. For example, the fluid conduit 10 can be configured to supply a diffused, spiral fluid flow from the flow shroud 70 of the fluid conduit 10. Figure 6 The spiral flow 77 entering the downstream portion of the aorta 14 from the pump may affect the performance of the system. For example, the spiral flow 77 may be clockwise relative to the direction of fluid flow. Alternatively, the spiral flow 77 may be counterclockwise relative to the direction of fluid flow. Other non-laminar flow patterns may be beneficial to the performance of the support systems and methods described herein.

[0062] In certain embodiments, the system may include one or more controllers for fluid conduits (e.g., Figure 2A In some embodiments, the device may include one or more sensors configured to provide pressure in the atrium as feedback to the controller. Figure 7 , the fluid conduit 10 that passes from the atrium 12 to the aorta 14 and is fixed via the wall 24 through the connector 22 may include sensors 120 and 122. Sensor 120 may be a pressure sensor on the surface of the fluid conduit 10 or deployed on an adjacent section of tissue. Sensor 122 may be an electrode sensor configured to monitor the activity of the myocardium. Each of the sensors can provide feedback to the controller, which in turn can adjust the speed of the pump and other characteristics that will control one or more of the chamber pressure, overall blood flow, fluid velocity, or a combination thereof. For example, monitoring pressure can reduce the onset of complications caused by the system. Examples of suitable sensors may include pressure sensors, electrical sensors (such as EKG sensors), or size sensors (such as ultrasound sensors).

[0063] refer to Figures 8A-8B , the fluid conduit design can have an impact on the flow dynamics at each of the inflow and outflow sections of the device. Figure 8AIn the embodiment of the present invention, the cannula 90 having an open tip (i.e., having a circular outlet formed at its distal end in a transverse plane relative to the longitudinal axis of the cannula) causes relatively more disturbance of the flow in the aorta 14 and even tends to inhibit or reverse some of the existing flow in the aorta 14. In addition, the flow into the atrium 12 of the cannula 90 causes relatively more chaotic flow in the atrium 12. By contrast Figure 8A and Figure 8B , using the fluid conduit 10 with the flow shield 70 provides more streamlined mixing with the existing flow in the aorta 14 , limited impact of the flow on the walls of the aorta 14 , and more streamlined flow in the fluid conduit 10 into the atrium 12 .

[0064] In some cases, the systems and methods described herein can be used as a percutaneous assist device for enhancing blood flow in a failing heart (e.g., a heart with congested atria or failing ventricles). In some cases, the methods provided herein can be used to position an assist device within a mammalian heart (e.g., within the aorta and left atrium of a human heart). The assist devices provided herein can be configured to reduce the risk of thrombosis and conform to the recipient's anatomy without causing damage to the heart or aorta.

[0065] The system and method can be used to treat various heart conditions. For example, the assist device provided herein can be used to support the function of the heart to treat congestive heart failure (e.g., left, right and bilateral failure), heart failure with preserved ejection fraction (diastolic heart failure or HFpEF), heart failure with reduced ejection fraction (systolic heart failure or HFrEF) or heart failure-induced arrhythmias (e.g., tachycardia and fibrillation). In some cases, the device can be combined to provide a complete cardiac system (e.g., left and right atrial devices), which can be used to supplement the failing heart. In some cases, the device provided herein can be used to support the damaged heart and maintain the circulation in the patient suffering from end-stage heart failure until a donor heart or artificial heart can be implanted (e.g., as a bridge to transplantation).

[0066] In some embodiments, the fluid conduit can be configured to supply a fluid flow from the outflow portion at a velocity of less than 3.0 m / s, less than 2.8 m / s, less than 2.6 m / s, less than 2.4 m / s, less than 22 m / s, less than 2.0 m / s, less than 1.8 m / s, less than 1.6 m / s, less than 1.4 m / s, less than 1.2 m / s, or less than 1.0 m / s. In some embodiments, the velocity can be greater than 0.01 m / s, greater than 0.05 m / s, greater than 0.1 m / s, greater than 0.2 m / s, greater than 0.3 m / s, or greater than 0.4 m / s. For example, the speed may be between 0.01 m / s and 3.0 m / s, between 0.05 m / s and 2.6 m / s, between 0.1 m / s and 2.4 m / s, between 0.2 m / s and 2.2 m / s, between 0.3 m / s and 2.2 m / s, or between 0.4 m / s and 2.0 m / s. In some cases, the maximum speed should not exceed 1.6 m / s.

[0067] In certain embodiments, the fluid conduit can be configured to provide a wall shear stress of less than 4500 dynes / cm from the outflow portion. 2 , less than 4000 dynes / cm 2 , less than 3500 dynes / cm 2 , less than 3000 dynes / cm 2 , less than 2500 dynes / cm 2 or less than 2000 dynes / cm 2 Importantly, the wall shear stress should be maintained below 4500 dynes / cm 2 To avoid tissue damage.

[0068] In certain embodiments, the fluid conduit can be configured to supply a fluid flow having a flow rate of less than 10 L / min, less than 8 L / min, less than 6 L / min, less than 4 L / min, less than 3 L / min, less than 2 L / min, or less than 1 L / min from the outflow portion. In certain embodiments, the flow rate can be greater than 0.30 L / min, greater than 0.40 L / min, greater than 0.50 L / min, greater than 0.60 L / min, greater than 0.70 L / min, greater than 0.80 L / min, greater than 1 L / min, greater than 2 L / min, greater than 3 L / min, greater than 4 L / min, or greater than 5 L / min. For example, the flow rate can be between 0.5 L / min and 10 L / min, between 1 L / min and 8 L / min, between 2 L / min and 6 L / min, or between 3 L / min and 5 L / min.

[0069] In certain embodiments, a suitable flow rate for partial support for HFrEF or HFpEF may be between 0.5 L / min and 3 L / min, eg, between 1.0 L / min and 3.0 L / min.

[0070] In certain embodiments, a suitable flow rate for complete support for HFrEF or HFpEF may be between 0.5 L / min and 10 L / min, eg, between 1 L / min and 8 L / min, preferably up to 6 L / min.

[0071] In certain embodiments, the method can include providing a pressure measurement or an estimate of the pressure in the left atrium as feedback to a controller for the fluid conduit. In certain embodiments, a sensor can provide pressure feedback to the controller. The controller can maintain the pressure in the left atrium at an optimal level for a given pathophysiology. In certain examples, the optimal level can be approximately 20 mmHg. In certain embodiments, relieving atrial pressure can improve the individual's physical function. Relief of atrial pressure and regulation of flow and other parameters can be performed by monitoring pulmonary capillary wedge pressure, left atrial pressure, pulmonary artery pressure, left ventricular end-diastolic pressure, VO2, six-minute walk parameters, or other physical characteristics.

[0072] Conventional left ventricular assist devices (LVADs) for HFrEF use a left ventricular apical cannula to unload the normally dilated left ventricle (LV). The support system described herein is designed for HFpEF / DHF and does not use an apical cannula. Apical cannulae in HFpEF patients may be at risk of flow obstruction due to overall LV cavity size and septal interference. Apical cannulae may also be undesirable due to the small intraluminal volume of the HFpEF LV coupled with the rigid, thickened LV wall. Alternatively, the support system described herein uses a left atrium to aorta (LA-Ao) approach to actively decompress the LA and reduce the risk of retrograde pulmonary congestion and the onset of right heart failure. Active decompression of the LA can result in a reduction in pulmonary capillary wedge pressure (PCWP) and central venous pressure (CVP).

[0073] Hemodynamics should be assessed at baseline before surgery. In an ideal world, PCWP would be monitored via an implanted pressure sensor and routinely checked at every hospital visit. Other methods used to assess the patient's condition are to measure vital signs and VO 2.maxExercise testing is performed using an ergonomic cycle while simultaneously performing the exercise test. Patients with heart failure (HFpEF) often have reduced exercise capacity. Active unloading of the LA and forward systemic flow is designed to increase exercise capacity in HFpEF patients, as demonstrated by reduced PCWP and increased six-minute walk time. Feedback can be provided to the controller via a wearable device (e.g., a smartwatch or other device).

[0074] Using the system described herein, an ideal target pressure in the LA can be maintained between 18 and 25 mmHg, for example, approximately 20 mmHg. The system utilizes a pressure sensor to maintain fill pressure to balance and actively decompress and prevent retrograde hyperemia.

[0075] The systems described herein can monitor LV filling pressure or a surrogate measure for filling pressure. In this way, the pump can proactively decompress the left atrium and prevent retrograde pulmonary and right ventricular loading by monitoring left atrial pressure (LAP), left ventricular pressure (LVP), PCWP, and right atrial pressure (RAP) in real time or near real time using sensors or other measuring devices.

[0076] Importantly, the system described herein can be used to treat either HFrEF or HFpEF, and is therefore a dual-purpose pump.

[0077] For example, the pressure can be reduced from a pulmonary artery wedge pressure of greater than 20 mmHg in HFrEF individuals to less than 20 mmHg, such as 10-15 mmHg.

[0078] In another example, the system can be used to maintain a pulmonary artery wedge pressure between 18 and 25 mmHg, such as approximately 20 mmHg, in individuals with HFpEF.

[0079] In another example, a pressure sensor or rate control may be adjusted to ensure adequate filling of the left ventricle in a subject with HFpEF.

[0080] In certain cases, the systems and methods can regulate atrial pressure.

[0081] In some cases, the systems and methods can reduce central venous pressure to less than 15 mmHg.

[0082] In some cases, the systems and methods can reduce right atrial pressure to less than 12 mmHg.

[0083] In certain embodiments, the fluid conduit can be positioned for optimal cleaning. For example, native blood flow within the left atrium provides cleaning of the fluid conduit. It may be important to keep the fluid conduit and pump free of any clots or thrombi. For example, at least a portion of the fluid conduit components can be coated with a non-thrombogenic surface coating, such as a functionalized acrylate polymer, phosphorylcholine (PC), polyethylene glycol (PEG), or polyethylene oxide (PEO). Figure 1 As shown, proper positioning within the atrium can improve cleaning flow.

[0084] The mammal may be a human.

[0085] In certain embodiments, a percutaneous lead can provide control for the pump.The lead can be passed through the atrial septum and routed through the venous system to exit the body.

[0086] A number of embodiments have been described. However, it will be appreciated that various modifications can be made without departing from the spirit and scope of the present disclosure. Accordingly, other embodiments are within the scope of the following claims.

Claims

1. A method of implanting a device into the heart of a mammal, the method comprising: A fluid conduit having an inflow portion and an outflow portion is inserted into the cardiovascular system of the mammal, wherein the inflow portion is located in the atrium of the heart of the mammal and the outflow portion is located in the aorta of the cardiovascular system of the mammal, and the fluid conduit passes from the atrium into the aorta. The method of claim 1 , wherein the atrium is the left atrium.

3. The method of claim 1, wherein the atrium is the left atrium and the outflow portion enters the descending portion of the aorta. The method according to claim 1 , wherein the outflow portion comprises a diffuser or a flow deflector.

5. The method of claim 1, wherein the fluid conduit includes structure for preventing the body of the fluid conduit from contacting a wall of the atrium to minimize thrombus formation and ingestion of thrombus into the fluid conduit. The method of claim 1 , wherein the fluid conduit is configured to supply a spiral fluid flow from the outflow portion. The method of claim 1 , wherein the fluid conduit is configured to supply a fluid flow from the outflow portion at a velocity less than 3.0 m / s.

8. The method of claim 1 , wherein the fluid conduit is configured to provide a wall shear stress of less than 4500 dynes / cm from the outflow portion. 2 of fluid flow.

9. The method of claim 1, wherein the atrium is the left atrium, and the method further comprises maintaining a pressure in the left atrium between 18 and 25 mmHg to assist a mammal with HFpEF.

10. The method of claim 1, wherein the atrium is the left atrium, and the method further comprises reducing the pressure in the left atrium to between 10 and 15 mmHg to assist a mammal with HFrEF.

11. The method of claim 1 , further comprising providing a signal from a sensor in the left atrium indicative of pressure in the left atrium as feedback to a controller for the fluid conduit.

12. The method of claim 1, wherein the fluid conduit comprises a pump.

13. A system for improving blood flow in a mammal, the system comprising: a fluid conduit having an atrial inflow portion and an aortic outflow portion; a pump disposed in the fluid conduit; and A controller is configured to operate the pump to regulate blood flow from the atrium to the aorta through the fluid conduit.

14. The system of claim 13, wherein the atrial inflow is in the left atrium and the aortic outflow is in the descending portion of the aorta.

15. The system of claim 13, wherein the controller adjusts the rate of blood flow through the catheter from the atrium to the aorta or the velocity of fluid through the catheter from the atrium to the aorta.

16. The system of claim 13, wherein the aortic outflow comprises a diffuser.

17. The system of claim 13, wherein the aortic outflow comprises a flow shield.

18. The system of claim 13, wherein the fluid conduit includes a cage for preventing the body of the fluid conduit from contacting a wall of the atrium to minimize thrombus formation and ingestion of thrombus into the pump.

19. The system of claim 13, wherein the fluid conduit is configured to supply a spiral fluid flow from the aortic outflow.

20. The system of claim 13, further comprising a pressure sensor coupled to the atrial inflow, wherein the pressure sensor is configured to provide a pressure measurement in the atrium as feedback to the controller.

Images