Shunt system and method with tissue growth prevention

Abstract

To provide a shunt system and a method with tissue growth prevention.SOLUTION: A shunt comprises a central flow portion configured to fit at least partially within an opening in a tissue wall. The tissue wall is situated between a first anatomical chamber and a second anatomical chamber and the opening represents a blood flow path between the first anatomical chamber and the second anatomical chamber. The central flow portion is further configured to maintain the blood flow path from the first anatomical chamber to the second anatomical chamber. The shunt further comprises a barrier configured to alter growth of tissue around the shunt.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] Related Applications This application claims priority to U.S. Provisional Application No. 62 / 975,024, filed February 11, 2020, entitled SHUNT SYSTEMS AND METHODS WITH TISSUE GROWTH PREVENTION, the entire disclosure of which is incorporated herein by reference.

[0002] The present invention relates generally to cardiac shunts and delivery systems and methods, and more particularly to shunts for reducing left atrial pressure. [Background technology]

[0003] Heart failure is a common and potentially fatal condition affecting humans, with suboptimal clinical outcomes often resulting in symptoms, morbidity, and / or mortality despite maximal treatment. Specifically, "diastolic heart failure" refers to the clinical syndrome of heart failure occurring in the presence of preserved left ventricular systolic function (ejection fraction) and the absence of major valvular disease. This condition is characterized by left ventricular stiffness, reduced compliance, and impaired relaxation, resulting in elevated end-diastolic pressure. Approximately one-third of patients with heart failure have diastolic heart failure, and few, if any, treatments have proven effective.

[0004] Symptoms of diastolic heart failure are at least in large part due to elevated left atrial pressure. Elevated left atrial pressure (LAP) is present in several cardiac conditions, including heart failure (HF). In addition to diastolic heart failure, several other medical conditions, including left ventricular systolic dysfunction and valvular disease, can increase left atrial pressure. Both heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF) can exhibit elevated LAP. It has been hypothesized that lowering LAP in both HF subgroups may advantageously reduce systolic preload on the left ventricle, i.e., left ventricular end-diastolic pressure (LVEDP). This may also relieve pressure on the pulmonary circulation, reducing the risk of pulmonary edema and improving breathing and patient comfort. Summary of the Invention [Means for solving the problem]

[0005] For purposes of summarizing the present disclosure, certain aspects, advantages, and novel features will now be described. It is to be understood that not necessarily all such advantages will be achieved in accordance with any particular embodiment. Thus, the disclosed embodiments may be implemented to achieve or optimize one advantage or group of advantages taught herein without necessarily achieving other advantages that may be taught or suggested herein.

[0006] Some implementations of the present disclosure relate to a shunt including a central flow section configured to fit at least partially within an opening in a tissue wall. The tissue wall is located between a first anatomical chamber and a second anatomical chamber, and the opening forms a blood flow path between the first anatomical chamber and the second anatomical chamber. The central flow section is further configured to maintain a blood flow path from the first anatomical chamber to the second anatomical chamber. The shunt further includes a barrier configured to alter growth around the shunt.

[0007] The shunt may further comprise one or more anchoring arms extending from the central flow section, The one or more anchoring arms may be configured to anchor to a tissue wall.

[0008] In some embodiments, the barrier extends from at least one of the one or more anchoring arms. The barrier may comprise one or more spikes extending from at least one of the one or more anchoring arms.

[0009] In some embodiments, the one or more spikes have a pointed end. The barrier may comprise a first spike and a second spike. The first spike may be configured to be located farther from the opening than the second spike.

[0010] In some embodiments, the barrier extends from the central flow section. The barrier may comprise a first portion configured to extend across a first side of the tissue wall. In some embodiments, the first portion is configured to extend at approximately 45 degrees across the first side of the tissue wall.

[0011] The barrier may include a second portion configured to extend across a second surface of the tissue wall, hi some embodiments, the first portion and the second portion form a single, continuous device.

[0012] The opening may have an elliptical shape, and the first portion may form at least a partial cone having a tapered elliptical shape, and the first portion extends across a complete ellipse of tissue on a first surface of the tissue wall. In some embodiments, the first portion does not extend across the opening.

[0013] The length of the first portion may be greater than the width and thickness of the first portion. In some embodiments, the first portion may have the shape of at least a partial oval ring with a hollow center configured to align with the opening. The shunt may further comprise one or more anchoring arms extending from the central flow portion. The one or more anchoring arms may be configured to anchor to a tissue wall. In some embodiments, a barrier extends from at least one of the one or more anchoring arms. The barrier may be configured to be located between the one or more anchoring arms and the tissue wall. In some embodiments, the central flow portion is further configured to prevent tissue ingrowth within the opening. The central flow portion may be configured to expand in response to expansion of the tissue wall.

[0014] Some implementations of the present disclosure relate to methods that include forming an opening in a tissue wall, treating an area of ​​tissue around the opening to prevent tissue ingrowth in the opening, and placing a shunt in the opening.

[0015] The region of tissue may have an oval shape and completely surround the opening, hi some embodiments, the shunt comprises a central flow portion configured to fit at least partially within the opening in the tissue wall.

[0016] The tissue wall may be located between the first anatomical chamber and the second anatomical chamber, and the opening may define a blood flow path between the first anatomical chamber and the second anatomical chamber. The central flow section may be further configured to maintain a blood flow path from the first anatomical chamber to the second anatomical chamber.

[0017] In some embodiments, the shunt further comprises a barrier configured to alter tissue growth around the shunt. Treating the region of tissue may include cauterizing the region of tissue.

[0018] Various embodiments are shown in the accompanying drawings for illustrative purposes, but these embodiments should not be construed as limiting the scope of the present invention. Furthermore, various features of different disclosed embodiments can be combined to form additional embodiments, and such additional embodiments are part of this disclosure. Reference numerals may be reused throughout the drawings to indicate correspondence between referenced elements. However, it should be understood that the use of like reference numerals in relation to multiple drawings does not necessarily imply that the associated embodiments are similar. Furthermore, it should be understood that the elements in each drawing are not necessarily drawn to scale, and that the depicted size of each element is presented for the purpose of illustrating aspects of the present invention. In general, some of the depicted elements may be relatively smaller than the elements illustrated in some embodiments or configurations. [Brief explanation of the drawings]

[0019] [Figure 1] 1A-1C illustrate several approaches for maneuvering guidewires and / or catheters within and around the heart to deploy an expandable shunt according to some embodiments. [Figure 2] 1A-1D illustrate a method for deploying an expandable shunt according to some embodiments. [Figure 3A] FIG. 10 is a side view of an opening through a tissue wall for placement of a shunt in the opening, according to some embodiments. [Figure 3B] FIG. 10 is a top view (e.g., from the left atrium) of an opening through a tissue wall for placement of a shunt in the opening, according to some embodiments. [Figure 4] 1A-1C illustrate a shunt having one or more barriers for preventing, containing, and / or inhibiting tissue growth at and / or around the opening in the shunt and / or tissue wall, according to some embodiments. [Figure 5]1A-1C illustrate a shunt having one or more barrier spikes for preventing, containing, and / or inhibiting tissue growth, according to some embodiments. [Figure 6] 10A-10C illustrate a method of preventing, inhibiting, and / or containing tissue growth comprising treating an area of ​​tissue around an opening according to some embodiments. [Figure 7] 1A-1C show a shunt having an upper barrier for preventing, containing, and / or inhibiting tissue growth, according to some embodiments. [Figure 8A] FIG. 1 illustrates a side view of a shunt having a lower barrier for preventing, containing, and / or inhibiting tissue growth, according to some embodiments. [Figure 8B] 1A-1C are top (e.g., left atrium) views of a shunt having a lower barrier for preventing, containing, and / or inhibiting tissue growth, according to some embodiments. [Figure 9] 1 is a flow diagram of an example process for delivering and / or anchoring a shunt to a human body according to some embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0020] The headings provided herein are for convenience of explanation only and do not necessarily affect the scope or meaning of the claimed invention.

[0021] overview In vertebrates, the heart is a hollow, muscular organ with four pumping chambers—the left and right atria and the left and right ventricles—each with its own one-way valve. Biological heart valves are identified as the aortic, mitral (or bicuspid), tricuspid, and pulmonary valves, each attached to an annulus with a dense fibrous ring attached directly or indirectly to atrial and ventricular muscle fibers. Each annulus defines a flow orifice. The four valves ensure that blood does not flow in the wrong direction during the cardiac cycle, i.e., blood does not backflow through the valves. Blood flows from the venous system and right atrium through the tricuspid valve to the right ventricle, then from the right ventricle through the pulmonary valve to the pulmonary artery and lungs. Oxygen-rich blood then flows from the left atrium through the mitral valve to the left ventricle, and finally from the left ventricle through the aortic valve to the aortic / arterial system.

[0022] Heart failure is a common and potentially fatal condition affecting humans, with suboptimal clinical outcomes often resulting in symptoms, morbidity, and / or mortality despite maximal treatment. Specifically, "diastolic heart failure" refers to the clinical syndrome of heart failure occurring in the presence of preserved left ventricular systolic function (ejection fraction) and the absence of major valvular disease. This condition is characterized by left ventricular stiffness, reduced compliance, and impaired relaxation, resulting in elevated end-diastolic pressure. Approximately one-third of patients with heart failure have diastolic heart failure, and few, if any, treatments have proven effective.

[0023] Symptoms of diastolic heart failure are at least largely due to elevated left atrial pressure. Elevated left atrial pressure (LAP) is present in several cardiac conditions, including heart failure (HF). In addition to diastolic heart failure, several other medical conditions, including left ventricular systolic dysfunction and valvular disease, can increase left atrial pressure. Both heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF) can exhibit elevated LAP. It has been hypothesized that lowering LAP in both HF subgroups may advantageously reduce systolic preload on the left ventricle, i.e., left ventricular end-diastolic pressure (LVEDP). This may also relieve pressure on the pulmonary circulation, reducing the risk of pulmonary edema and improving respiratory and patient comfort.

[0024] Pulmonary hypertension (PH) is defined as elevated mean pressure in the main pulmonary arteries. PH can develop due to many different causes, but all patients have been shown to have a high mortality rate. Fatal PH occurs in the very small arterial branches of the pulmonary arteries and is called pulmonary arterial hypertension (PAH). In PAH, cells inside small arteries proliferate due to injury or disease, narrowing the arterial interior surface area and thickening the arterial walls. As a result, these small pulmonary arteries narrow and stiffen, thereby restricting blood flow and increasing upstream pressure. This elevated pressure in the main pulmonary arteries is a common link between all forms of PH, regardless of the underlying cause. Despite previous attempts, improved methods are needed to reduce elevated pressure in the left atrium, as well as other affected heart chambers, such as the pulmonary artery.

[0025] The present disclosure provides methods and devices that can reduce elevated LAP by shunting blood from a first anatomical chamber (e.g., the left atrium) to a second anatomical chamber (e.g., the coronary sinus). While some embodiments herein may be described with respect to treating LAP and / or similar problems, the described shunting devices and methods may be used to treat other problems, including dialysis. Some embodiments include a shunt that defines an open pathway between the left atrium and the coronary sinus. However, this method can be used to place shunts between other heart chambers, such as between the pulmonary artery and the right atrium. The term "shunt" is used herein in its broad, ordinary sense and may include any shunting means and / or means for shunting blood between and / or from one anatomical chamber and / or blood flow path to another. The shunt may be configured to prevent early collapse of the open pathway and to prevent tissue ingrowth on at least the interior surface of the open pathway. In some embodiments, the shunt may be expandable so that it can be compressed, delivered through a low-profile sheath or tube, and removed to resume the expanded state. Some methods may include utilizing a deployment catheter that can first create a puncture hole in the tissue wall between the left atrium and the coronary sinus. The catheters described herein may include any delivery means and / or means for delivering one or more implants into a patient's body.

[0026] Furthermore, in some embodiments, the shunt may be configured to expand in response to tissue wall expansion after delivery. For example, some patients, and particularly HF patients, may experience amyloidosis, a protein disorder in which amyloid deposits in the heart can harden and / or thicken the heart wall. Shunt implants with maximum tissue wall thickness specifications may not be configured to accommodate a certain level of tissue growth / expansion. For example, some shunt implants may have a wall thickness specification of approximately 4 mm. However, many amyloidosis patients may experience tissue wall thicknesses that continue to increase beyond 4 mm, thus creating patency issues for the shunt implant after implantation. Therefore, it may be advantageous for the shunt implant to include elements configured to form a physical barrier to tissue growth and / or for the shunt implant to be delivered in conjunction with devices and methods for preventing and / or inhibiting tissue growth. For example, the barrier may include walls, spikes, rings, or other devices that may extend from and / or be attached to the shunt to prevent, inhibit, and / or contain tissue growth at and / or around the opening in the shunt and / or tissue wall. In some embodiments, the shunt implant may also be at least partially expandable and / or configured to "grow" in response to tissue growth.

[0027] Thus, the shunt implants described herein may include a central flow section and / or anchoring arms that may be configured to attach to various mechanical components configured to prevent and / or inhibit tissue growth. Optional anchoring means and / or means for anchoring the shunt implant and / or portions of the shunt implant may be included. In some embodiments, the shunt implant may be delivered using methods configured to prevent and / or inhibit tissue growth around and / or near the shunt implant. The shunt implant may incorporate various mechanical systems to prevent and / or inhibit tissue growth. Details of these methods, implants, and deployment systems are described below.

[0028] 1 illustrates several access routes for maneuvering guidewires and catheters in and around the heart 1 to deploy the expandable shunt of the present application. For example, an access route may begin from above via the subclavian vein 11 or jugular vein 12 into the superior vena cava (SVC) 15, the right atrium (RA) 5, and from there into the coronary sinus (CS) 19. Alternatively, an access route may begin in the femoral artery 13 and enter the heart 1 through the inferior vena cava 14. Other access routes may also be used, each generally utilizing a percutaneous incision through which the guidewire and catheter are inserted into the vasculature, usually with a sealed introducer, from which the physician controls the distal end of the device from outside the body.

[0029] Figure 2 illustrates a method for deploying various implants 10, including the expandable shunts described herein, in this case, by introducing a catheter 16 through the subclavian or jugular vein, through the SVC 15, and into the coronary sinus 19. After the guidewire forms a pathway, an introducer sheath may be advanced into the patient's vasculature along the guidewire, typically with the use of a dilator. Figure 2 illustrates the deployment catheter 16 extending from the SVC 15 to the coronary sinus 19 of the heart 1, with the deployment catheter 16 passing through the introducer sheath, which forms a hemostatic septum to prevent blood loss.

[0030] In one embodiment, the deployment catheter 16 may be approximately 30 cm in length, and the guidewire may be somewhat longer than 30 cm for ease of use. In some embodiments, the deployment catheter may serve to prepare the opening in the wall of the left atrium 2, and a separate placement or delivery catheter is used to deliver the expandable shunt. In other embodiments, the deployment catheter may be used as a full-function puncture hole preparation and shunt placement catheter. In this application, the terms "deployment catheter" or "delivery catheter" are used to refer to catheters or introducers that have one or both of these functions.

[0031] The coronary sinus 19 is primarily adjacent to and surrounds the left atrium 2, allowing for a variety of acceptable placements for the stent. The site selected for stent placement may be an area of ​​thinner or less dense tissue in a particular patient, as previously determined by non-invasive diagnostic means such as a CT scan or radiographic techniques such as fluoroscopy or intravascular ultrasound (IVUS).

[0032] Some methods for reducing LAP include utilizing a shunt through the interatrial septum between the left atrium 2 and the right atrium 5. This is an advantageous approach because the two structures are adjacent and transseptal access is a common method. However, emboli can potentially migrate from the right to the left side of the heart, creating a risk of stroke. This event is thought to occur primarily during discrete events such as coughing, sneezing, the Valsalva maneuver, or defecation, when right atrial pressure exceeds left atrial pressure. The anatomical location of the septum naturally allows emboli to move freely between the atria when a shunt is present and the pressure gradient is reversed. This is mitigated by valve or filter elements within the shunt, but emboli may still traverse it.

[0033] Shunting to the coronary sinus 19 has several notable advantages, primarily that the coronary sinus 19 is significantly less likely to harbor emboli for several reasons. First, blood leaving the coronary vasculature and flowing into the right atrium 5 has just passed through the capillaries and is therefore essentially filtered blood. Second, the mouth of the coronary sinus 19 in the right atrium 5 is often partially covered by a pseudovalve called the Thebesian valve. The Thebesian valve is not always present, and several studies have found that it is present in over 60% of hearts and acts as a biological "watchdog" for the coronary sinus, preventing emboli from entering if right atrial pressure suddenly rises. Third, the pressure gradient between the coronary sinus 19 and the right atrium 5, where emboli enter, is very low, meaning that emboli in the right atrium 5 are likely to remain lodged there. Fourth, if an embolus enters the coronary sinus 19, a much greater gradient exists between the right atrium 5 and the coronary vasculature than between the right atrium 5 and the left atrium 2. The embolus will most likely travel further along the coronary vasculature until right atrial pressure returns to normal, and then the embolus will return directly to the right atrium 5.

[0034] Some additional benefits of placing a shunt between the left atrium 2 and the coronary sinus 19 are that this anatomy is less mobile (more stable) than the septum, thus preserving the septum for later transseptal access for alternative treatments, which may provide other therapeutic benefits in some cases. By routing left atrial blood into the coronary sinus 19, sinus pressure may be slightly elevated. This allows blood in the coronary vasculature to move through the heart at a slower rate, increasing perfusion and oxygen transfer, and may also help necrotic myocardium recover through more efficient perfusion and oxygen transfer. The Neovasc Reducer is a device designed to do exactly this. Preserving transseptal access is also a significant advantage, as HF patients often have several other comorbidities, such as atrial fibrillation (AF) and mitral regurgitation (MR), and some therapies to treat these conditions require a transseptal approach.

[0035] Shunts may also be placed between other heart chambers, such as between the pulmonary artery and the right atrium 5. Shunts may desirably be implanted within the wall of the pulmonary artery by approaching from above and passing a catheter through the pulmonary artery using the deployment device described herein. As discussed above, pulmonary hypertension (PH) is defined as an increase in mean pressure within the main pulmonary artery. Blood flows through the shunt in the direction from the pulmonary artery into the right atrium 5 when a pressure difference causes blood to flow in that direction, thereby attenuating pressure and reducing damage to the pulmonary artery. The purpose is to attenuate pressure spikes within the pulmonary artery. Shunts may also extend from the pulmonary artery to other heart chambers (e.g., the left atrium 2) and / or blood vessels. While not preferred or illustrated, shunts may further include one-way valves to prevent backflow or check valves to only allow blood above a specified pressure. This application discloses novel shunts for maintaining a flow path between heart chambers. Some shunts described herein may be at least partially expandable. Furthermore, in some embodiments, shunts may have various elements and / or may be used in combination with devices having various barriers to prevent, inhibit, and / or contain tissue growth. As used herein, the term "barrier" is used in accordance with its broad, ordinary meaning and may include any feature of a shunt and / or configured for use with a shunt to at least partially prevent, inhibit, reduce, contain, and / or otherwise alter tissue growth in and / or around the shunt. The shunts described herein may have various elements to simplify and / or enhance the delivery procedure for a surgeon. For example, the shunt may be at least partially flexible, compressible, and / or resilient to allow it to be shaped and / or molded as needed / desired to conform to openings and / or tissue walls having various sizes and / or shapes.

[0036] FIG. 3A is a side view, and FIG. 3B is a view from above (e.g., left atrium 2) of an opening (i.e., puncture hole) 311 through a tissue wall 308 (e.g., between the coronary sinus 19 and left atrium 2) within which a shunt is placed. As shown in FIG. 3A, a shunt deployment or delivery catheter 350 may be advanced to the tissue wall 308 between two cavities (e.g., the coronary sinus 19 and left atrium 2). A first side 301 of the tissue wall 308 may lie in plane with a first anatomical chamber (e.g., the left atrium 2) and / or a second side 303 of the tissue wall 308 may lie in plane with a second anatomical chamber (e.g., the coronary sinus 19). The catheter 350 may have a soft and / or tapered distal tip 352. A delivery catheter 350 may be advanced through an opening 311 in the tissue wall 308, for example, into the left atrium 2. The opening may be formed in any of a variety of ways. One exemplary method is described below.

[0037] First, a guidewire may be advanced into the coronary sinus 19, for example, from the right atrium through the ostium or opening of the coronary sinus 19. A puncture catheter may be advanced along the guidewire. The puncture catheter may be introduced into the body through the proximal end of an introducer sheath. The introducer sheath may allow access to a specific vascular pathway (e.g., the carotid artery or subclavian vein) and may have a hemostatic valve therein. The surgeon can manipulate the puncture catheter to the implantation site while holding the introducer sheath in a fixed position. A puncture catheter having a puncture needle including a sharp tip is advanced along the catheter and punctures the wall 308, for example, into the left atrium 2. A puncture expander may be advanced along the guidewire and penetrate the tissue wall 308 into the left atrium 2. The puncture expander may be, for example, an elongated inflatable balloon. The puncture expander may expand radially outward to widen the puncture hole through the tissue wall 308.

[0038] The shunt may be delivered through the lumen of the catheter 350. During delivery, the shunt may be in a collapsed configuration to facilitate delivery. For example, the shunt may be rolled, bent, twisted, and / or otherwise formed to have a minimal profile to facilitate delivery through the catheter 350. The shunt may be positioned within the annular space between the inner and outer sheaths of the catheter 350. The inner sheath may be retracted so that the shunt is positioned in close engagement with the tissue wall 308. Radiopaque markers may be provided to facilitate placement of the catheter 350 and / or shunt. By forming an opening between the left atrium 2 and the coronary sinus 19, blood can flow from the left atrium 2 (typically >8 mmHg) to the coronary sinus 19 (typically <8 mmHg).

[0039] FIG. 4 illustrates a shunt 400 having one or more barriers 404 for preventing, containing, and / or inhibiting tissue growth at and / or around the opening in the shunt 400 and / or tissue wall, according to some embodiments. As used herein, the term “barrier” may refer to any portion of material configured to form a barrier and / or obstruction between at least a portion of the tissue and at least a portion of the opening in the shunt and / or tissue wall 408. The shunt 400 may comprise any of a variety of elements and / or components configured to maintain an opening in the tissue wall 408 and / or allow blood flow through the tissue wall 408. In some embodiments, the shunt 400 may comprise a central flow portion 402 that may be configured to be at least partially located within the opening in the tissue wall 408. In some embodiments, the shunt 400 may comprise multiple separate components that may be attached, connected, and / or otherwise joined to form a single device. For example, the central flow portion 402 may include multiple components to form a generally tubular shape that may approximate the shape of the opening in the tissue wall 408. For example, the opening may have a generally oval (e.g., circular) shape (see, e.g., FIG. 3B ), and the central flow portion 402 may be configured to form a generally cylindrical and / or tubular shape to fit within and / or press against the surface of the tissue wall 408 at the opening.

[0040] One or more walls 404 may be configured to extend outwardly from the central flow section 402 and / or from one or more anchoring arms 414 of the shunt 400. For example, the wall 404 may extend from and / or be attached to the central flow section 402, while the one or more walls 404 may extend from and / or be attached to at least one of the one or more anchoring arms 414. In some embodiments, the one or more walls 404 may extend outwardly from the V-shaped central flow section 402. For example, the first wall 404a may extend from the central flow portion 402 in a first direction (e.g., on the first surface 401 of the tissue wall 408), and the second wall 404b may extend from the central flow portion 402 in a second direction (e.g., on the second surface 403 of the tissue wall 408), forming a first angle 410 between the first wall 404a and the second wall 404b. For example, the first angle 410 may be approximately 90 degrees. In some embodiments, the wall 404 may comprise an elongated sheet that curves at a central portion of the wall 404 to form a first portion (i.e., the first wall 404a) and a second portion (i.e., the second wall 404b) that extend outward from the central flow portion 402 in different directions, forming the first angle 410 of separation between the walls 404. Thus, the first wall 404a and the second wall 404b may comprise a single, continuous device.

[0041] In some embodiments, the wall 404 may comprise a sheet of material having a relatively small thickness 416 compared to the width 418 of the wall 404 and / or may have a relatively small thickness 416 and / or width 418 compared to the length 420 of the wall 404. However, the wall 404 may have a thickness 416, width 418, and / or length 420. Each wall 404 may have a common thickness 416, width, and / or length 420, or individual walls 404 may have different thicknesses 416, widths, and / or lengths 420. As shown in FIG. 4 , the shunt 400 may comprise multiple distinct walls 404 having distinct and / or finite widths 418. However, in some embodiments, the walls 404 may have a generally conical shape, and the widths 418 of the walls 404 may extend generally elliptically, forming a complete ellipse or nearly a complete ellipse. For example, each of the first wall 404a and / or the third wall 404c may extend non-linearly until they join together to form a generally conical shape. For example, the walls 404 may have a generally elliptical shape, forming a perfect or nearly perfect elliptical tissue shape above the tissue wall (e.g., forming a perfect elliptical tissue shape on the first surface 401 of the tissue wall 408). Thus, the first wall 404a and the third wall 404c may extend laterally (e.g., along the first line 430) to form a single continuous wall 404 (e.g., having at least a partial conical shape) around the first surface 401 of the tissue wall 408. Similarly, the second wall 404b and the fourth wall 404d may extend to form a single continuous wall. Additionally, the walls 404 may have a generally tapered shape, with the diameter of the wall 404 increasing as the wall 404 extends further from the central flow section 402 and / or the opening. The wall 404 may have only a partial conical shape, as it may have a hollow center configured to align with the opening in the tissue wall 408. Thus, the wall 404 may not extend across the opening in the tissue wall 408.

[0042] Furthermore, the first wall 404a, the second wall 404b, the third wall 404c, and the fourth wall 404d may form a double cone or a partial double cone, and the apex of the double cone may be a true apex at or near the central flow section 402, and / or there may be no apex and the double cone shape of the wall 404 may have a hollow center that approximates an opening in the tubular-shaped central flow section 402 and / or tissue wall 408.

[0043] The walls 404 may be configured to prevent, inhibit, and / or contain tissue growth around the shunt 400. Each wall 404 may extend outward from the central flow portion 402 across a portion of the tissue wall 408. For example, the first wall 404a may extend across a portion of the first surface 401 of the tissue wall 408. As shown in FIG. 4, the first wall 404a may extend at a second angle 412 from the first surface 401 of the tissue wall 408. In some embodiments, the first wall 404a may extend in a generally parallel or perpendicular direction to the tissue wall 408. While the first wall 404a and / or the other walls 404 are shown as having a generally straight shape, each wall 404 may have a curvature and / or may bend at various points as desired. The walls 404 may be configured to extend at any angle across the tissue wall 408 (e.g., the first surface 401 of the tissue wall 408). For example, the wall 404 may be configured to extend such that the second angle 412 between the first wall 404a and the first surface 401 of the tissue wall is approximately 45 degrees.

[0044] In some embodiments, the wall 404 may be configured to at least partially penetrate and / or pass through the tissue wall 408. For example, the wall 404 may extend outward from the central flow portion 402 into the tissue wall 408. The wall 404 may be partially embedded in the tissue wall 408 and / or a portion of the tissue wall 408 may protrude from the tissue wall 408.

[0045] As the tissue wall 408 thickens and / or otherwise expands (e.g., growing inward toward the central flow portion 402), tissue may be forced against the wall 404. The wall 404 may be at least partially composed of a solid material and / or may be composed of a mesh of interconnected material that is dense enough to prevent and / or at least partially inhibit tissue growth through the wall 404.

[0046] Any of the one or more anchoring arms 414 may include one or more anchoring mechanisms, which may be located, for example, at the end of the anchoring arm. Suitable anchoring mechanisms may include any device configured to penetrate and / or otherwise firmly contact a tissue wall. For example, the anchoring mechanism may include one or more of a barb, a hook, a nail, and a screw. When the shunt 400 is positioned in the tissue wall 408, the anchoring mechanism may be configured to interact with the tissue wall 408 to firmly hold the shunt 400 in place.

[0047] Various elements of the shunt 400, including the central flow section 402 and / or the anchoring arms 414, described herein may apply to shunt devices described and / or shown in other figures of the present application. For example, any description regarding the shunt 400 shown in FIG. 4 may equally apply to the shunt 500 in FIG. 5, the shunt 700 in FIG. 7, and / or the shunt 800 in FIGS. 8A and 8B described herein. Furthermore, it should be understood that other shunts shown and / or described with respect to other figures may not include the wall 404 as shown in FIG. 4, although the wall 404 may be added to shunts described with respect to other figures. Similarly, various elements described with respect to other figures herein may be added to the shunt 400 in FIG. 4 and / or other figures herein even if the shunt 400 is not shown and / or described with respect to each figure.

[0048] In some embodiments, the shunt 400 may be configured to be movable between an expanded configuration and a collapsed (e.g., generally tubular) configuration to facilitate passage through a catheter lumen. For example, the central flow section 420 may be configured to be rolled, bent, twisted, or otherwise compressed to fit within a catheter lumen. The central flow section 402 may be configured to expand to a predefined shape and / or size during and / or after delivery within the body. The shunt 400 may further comprise one or more anchoring arms 414, which may include flanges, arms, anchors, and / or other devices. The one or more anchoring arms 414 may be configured to at least partially collapse to facilitate passage through a catheter lumen and may be configured to expand during and / or after delivery within the body to contact and / or attach to a tissue wall 408. Expansion of the shunt 400 may be initiated, for example, by retracting the outer sheath of the catheter relative to the inner sheath. The shunt 400 may be folded (e.g., crimped) into a generally tubular configuration between two straightened sheaths with the anchoring arms 414 configured to open under spring force when the outer sheath restraining the inner sheath is retracted. Rather than expanding in a circular fashion, the anchoring arms 414 may expand in generally opposite directions in a common plane to form a T. Radiopaque markers may be provided on the anchoring arms 414 to facilitate direct placement within the left atrium.

[0049] The pair of anchoring arms 414 (e.g., first anchoring arm 414a and second anchoring arm 414b) may form a clamping (i.e., pinching) pair of anchoring arms. The pair of anchoring arms 414 may be configured to apply a compressive force to the tissue wall 408 to hold the shunt 400 in place. The amount of compressive force may be sufficient to hold the shunt 400 in place, while being relatively small to avoid damage to the tissue wall 408. For example, the gap separating the pair of anchoring arms may be calibrated to avoid excessive clamping and / or necrosis of tissue. The anchoring arms 414 may be configured to secure the shunt 400 generally on opposite sides of the tissue wall 408 (e.g., a first anchoring arm 414a disposed on the first side 401 of the tissue wall 408 and a second anchoring arm 414b disposed on the second side 403 of the tissue wall 408) and / or generally on opposite sides of an opening in the tissue wall 408. The central flow section 402 may be configured to be aligned generally perpendicular to the tissue wall 408 to maintain an open flow path between the chambers on each side of the tissue wall 408 (e.g., the coronary sinus and the left atrium).

[0050] The components of the shunt 400 may be configured to naturally self-expand due to the inherent elasticity and / or flexibility of each component. For example, various components (e.g., the central flow section 402, the anchoring arms 414, and / or the wall 404) may be constructed of a resilient material such as Nitinol. In some embodiments, the central flow section 402 may be fabricated by laser cutting a Nitinol tube. The central flow section 402 may have a wall thickness of between about 0.1 mm and about 0.3 mm.

[0051] As shown in FIG. 4 , the central flow section 402 may be comprised of generally thin struts 407 in a generally parallelogram configuration that may form an array of parallelogram-shaped cells 409 or openings. However, the central flow section 402, including struts 407 and / or cells 409, may have any shape, size, and / or orientation. For example, the struts 407 may have a generally thicker design than that shown in FIG. 4 to minimize the size of the cells 409, thereby further preventing tissue ingrowth within the central flow section 402. Instead of a generally parallelogram shape, the cells 409 may have a generally oval, triangular, hexagonal, or other shape. Furthermore, the central flow section 402 may not include cells 409. In some embodiments, the shape of the struts 407, cells 409, and / or central flow section 402 may generally facilitate collapsibility and / or expandability of the central flow section 402 for passage through a lumen of a catheter.

[0052] Flow portion 402 may be configured to form a generally cylindrical or other shape to approximate the shape of the opening. In some embodiments, the opening may widen generally evenly in all directions from the puncture point to form a generally circular opening having a diameter. Thus, flow portion 402, including struts 407, may have an at least partially rounded and / or circular shape around (i.e., into) the opening along its longitudinal axis.

[0053] In some embodiments, the expandable shunt 400 may be in a compressed and / or possibly expandable configuration during delivery. For example, during delivery, the central flow section 402, anchoring arms 414, and / or walls 404 may be folded, bent, and / or otherwise compressed to have a minimal shape to facilitate passage through a delivery catheter. After delivery, the central flow section 402, anchoring arms 414, and / or walls 404 may be configured to unfold, open, and / or expand (e.g., to form the configuration shown in FIG. 4). In some embodiments, at least a portion of the central flow section 402, anchoring arms 414, and / or walls 404 may be composed of nitinol and / or a similar material with shape-memory properties, such that the shunt 400 may naturally assume a predetermined configuration after being removed from the delivery catheter.

[0054] Additionally, the central flow portion 402 and / or the anchoring arms 414 may be configured to expand in response to growth and / or expansion of the tissue wall 408. The first anchoring arms 414a and the second anchoring arms 414b may be configured to further separate from one another to some extent, for example, to accommodate growth of the tissue wall 408 as the tissue wall 408 expands (i.e., thickens). In some embodiments, the central flow portion 402, the anchoring arms 414, and / or the wall 404 may be configured to stretch in response to expansion of the tissue wall 408. For example, the central flow portion 402, the anchoring arms 414, and / or the wall 404 may be at least partially constructed of a flexible and / or elastic material that allows for some stretching. The shunt 400 may be configured to stretch to accommodate expansion of the tissue wall 408 as the tissue wall 408 expands.

[0055] While each of Figures 4-8 may depict medical implants and / or processes that include elements for preventing, containing, and / or inhibiting tissue growth at or near the medical implant, these elements may be used independently of one another or in combination with one another. For example, a shunt 400 as shown in Figure 4 may include a wall 404 for managing tissue growth without any additional elements for managing tissue growth. Alternatively, for example, the wall 404 and / or other elements described herein may be utilized in combination with other elements. For example, the shunt 400 may include one or more spikes (shown in Figure 5) and / or barriers (shown in Figures 7 and 8) extending from the wall 404 and / or other regions of the shunt 400. As another example, the tissue wall 408 may be treated (as shown in Figure 6) before the shunt 400 and / or any other shunt described herein is delivered.

[0056] 5 shows a shunt 500 having one or more barrier spikes 504 for preventing, containing, and / or inhibiting tissue growth, according to some embodiments. The shunt 500 may include a central flow portion 502 and / or one or more anchoring arms 514 similar to the central flow portion 502 and anchoring arms 514 described above with respect to FIG. 4. The anchoring arms 514 may be configured to extend from the central flow portion 502 to contact and / or attach to the first surface 501 and / or the second surface 503 of the tissue wall 508.

[0057] The shunt 500 may further comprise one or more spikes 504, which may include needles, rods, bumps, and / or other protrusions that may extend from the anchoring arms 514 and / or the central flow portion 502. While FIG. 5 shows two spikes 504 extending from each anchoring arm 514, any number of spikes 504 may extend from an anchoring arm 514 and / or one or more spikes 504 may extend from the central flow portion 502. In some embodiments, the spikes 504 may be composed of a different material than the anchoring arms 514 and / or the central flow portion 502, or the spikes 504 may represent separate components from the anchoring arms 514 and / or the central flow portion 502 and may be attached to the anchoring arms 514 and / or the central flow portion 502.

[0058] In some embodiments, the spike 504 may be an overall thin device and may have a base portion 505 that contacts the anchoring arms 514 and / or the central flow portion 502. The spike 504 may extend from the base portion 505 to an end portion 507. In some embodiments, the distance from the base portion 505 to the end portion 507 (i.e., the length of the spike 504) may exceed the thickness of the spike 504. However, the spike 504 may have any thickness, and the length of the spike 504 may be less than the thickness of the spike 504. Although the spike 504 is shown extending generally perpendicular to the tissue wall 508, it may extend at any angle from the shunt 500 and / or the tissue wall 508. For example, the spike 504 may extend diagonally away from the central flow portion 502 and / or opening or diagonally toward the central flow portion 502 and / or opening.

[0059] The ends 507 of the spikes 504 may be generally pointed, rounded, and / or have any other shape. In some embodiments, the ends 507 may be sharp enough to penetrate tissue. For example, as the tissue wall 508 grows / expands, the tissue may extend at least partially over the anchoring arms 514 and / or central flow portion 502. The tissue may contact the spikes 504, which may be sufficiently stiff so that the tissue cannot penetrate the spikes 504 but must grow over them. The ends 507 may be configured to penetrate and / or press against the tissue as the tissue extends over the ends 507 of the spikes 504, causing the tissue to retract and / or stop growth over the shunt 500 in at least one direction.

[0060] In some embodiments, the spikes 504 may be positioned at multiple levels. For example, the first spike 504a may be positioned near the distal end of the anchoring arm 514 (i.e., distal from the central flow portion 502), and the second spike 504b may be positioned near the central flow portion 502. That is, the first spike 504a may be farther from the central flow portion 502 and / or opening than the second spike 504b. As the tissue wall 508 grows / expands, the tissue may contact the second spike 504b after passing the first spike 504a.

[0061] Spike 504 may have various elements for penetrating and / or possibly inhibiting tissue growth. For example, spike 504 may include multiple smaller spikes 504 that may extend generally perpendicularly from spike 504. Thus, as tissue grows onto spike 504, the smaller spikes may penetrate and / or press against the tissue to provide an additional barrier to the tissue. Similarly, spike 504 may have a raised surface and / or be coated with a gritty or similar abrasive material to provide an obstacle to tissue growth.

[0062] The various embodiments and / or elements of the embodiments described herein may be combined. For example, one or more spikes 504 may extend from the wall 404 described herein with respect to FIG.

[0063] 6 illustrates a method of preventing, inhibiting, reducing, and / or containing tissue growth, according to some embodiments, including treating one or more regions 604 of tissue around and / or near an opening 611 in a tissue wall 608. The method may include firing, cutting, removing, cauterizing, scarring, and / or otherwise treating one or more regions 604 of tissue. The regions 604 of tissue may include a portion of an outer surface of the tissue wall 608 (e.g., on the left atrial or coronary sinus surface of the tissue wall 608) and / or on an inner surface of the tissue wall 608 (e.g., within the opening 611 in the tissue wall 608).

[0064] In some embodiments, one or more regions of tissue 604 may be treated before, during, and / or after placing the shunt at or near the opening 611. Various instruments used in treating one or more regions of tissue 604 may be delivered. For example, a laser or similar device may be used to remove and / or cauterize the region of tissue 604. Treatment of one or more regions 604 may include using electroablation and / or electrocautery instruments to create a controlled scar pattern and / or interrupt electrical conduction in the region of tissue 604.

[0065] As shown in FIG. 6 , the region 604 may have an elliptical (circular) shape and / or may approximate the shape of the opening 611 in the tissue wall 608. For example, the opening 611 may have a generally circular shape with a first radius 609, and the region 604 may similarly have a generally circular shape with a second radius 610 that may be larger than the first radius 609. However, one or more regions 604 may have any size and / or shape. For example, the region 604 may not comprise a perfect ellipse, but instead may include straight, jagged, curved, non-linear, etc. shapes that may be located at or near the anchoring location of the shunt implant. In some embodiments, multiple regions 604 may be formed. For example, multiple elliptical or semi-elliptical regions 604, each having a different size and / or radius, may form an elliptical or other shape. The one or more regions 604 may constitute multiple levels of treated tissue along a lateral axis extending from the opening 611. For example, the first region 604 of tissue may itself have one or more overlapping corrugations along a single axis extending from the opening 611. In another example, the first region 604 may be located a first distance along the transverse axis from the opening 611, and the second region 604 may be located a second distance along the transverse axis from the opening 611, where the second distance is greater than the first distance. In other words, the second region 604 may be located distal to the opening 611, and the first region 604 may be located proximal to the opening 611. In some embodiments, the region 604 may have any thickness 606 and / or may have any sized gap 612 between the opening 611 and the region 604.

[0066] In some embodiments, region 604 may be treated in connection with delivery of a shunt as described herein. The shunt may be at least partially disposed within opening 611. The shunt may have one or more anchoring arms configured to span and / or contact the tissue wall 608 around opening 611. In some embodiments, the anchoring arms of the shunt may be configured to extend across region 604 or not extend beyond the gap 612 between opening 611 and region 604. The shape and / or size of region 604 may be selected based on the shape and / or size of the shunt disposed in opening 611. For example, region 604, shaped to tightly surround at least a portion of the shunt, may be treated before and / or after the shunt is deployed. In this manner, region 604 may be configured to prevent tissue growth and / or ingrowth in and / or around the shunt.

[0067] 7 illustrates a shunt 700 having an upper barrier 704 for preventing, containing, and / or inhibiting tissue growth, according to some embodiments. In some embodiments, the upper barrier 704 may have an elliptical and / or torus shape. The upper barrier 704 may form a complete or partial ring around a hollow center of the ring. The hollow center may be configured to align with an opening in the tissue wall 708 and / or a flow path formed and / or maintained by the central flow portion 702 of the shunt 700. For example, the central flow portion 702 may define a flow path through the tissue wall 708, and the upper barrier 704 may be configured to surround but not obstruct (or only partially obstruct) the flow path.

[0068] 7 shows a cross-sectional view of the shunt 700, the upper barrier 704 is shown as having a partial elliptical shape. However, the upper barrier 704 may form a complete ellipse around the opening in the tissue wall 808. The upper barrier 704 may have any shape. For example, the upper barrier 704 may have a rectangular, triangular, pentagonal, octagonal, or other shape and / or may include a hole in the center of the upper barrier 704 to allow flow through it.

[0069] Although the upper barrier 704 is shown having a generally thin structure, the upper barrier 704 may have any thickness 706. Additionally, the upper barrier 704 may have a variable thickness 706. For example, the upper barrier 704 may have an at least partially rounded surface, in which case the cross section of the upper barrier 704 has an elliptical shape similar to a torus.

[0070] In some embodiments, the upper barrier 704 may be configured to extend from and / or be attached to the central flow portion 702 and / or one or more anchoring arms 714 of the shunt 700. For example, the upper barrier 704 may be attached to and / or extend from the first anchoring arm 714a and / or the second anchoring arm 714b. The first anchoring arm 714a and the second anchoring arm 714b may be located generally on opposite sides of an opening on the first surface 701 of the tissue wall 708 (or the second surface 703 of the tissue wall 708). In some embodiments, the upper barrier 704 may constitute the portion of the shunt 700 furthest from the first surface 701 of the tissue wall 708 and / or the second surface 703 of the tissue wall 708.

[0071] 7 shows only a single upper barrier 704, the shunt 700 may include multiple upper barriers 704. For example, the shunt 700 may include a second upper barrier 704 on the second surface 703 of the tissue wall 708, extending from and / or attached to the central flow portion 702 and / or one or more anchoring arms 714. Furthermore, although the upper barrier 704 is shown as extending from and / or attached to one or more proximal portions 716 of the anchoring arms 714, the upper barrier 704 may be configured to extend from and / or attach to any portion of the anchoring arms 714 and / or central flow portion 702. For example, the upper barrier 704 may be configured to be attached to and / or extend from one or more end portions 718 of the anchoring arms 714. In some embodiments, the hole in the central portion of the upper barrier 704 may be large enough that one or more proximal portions 716 of the anchoring arms 714 may be configured to fit into and / or pass through the hole when the upper barrier 704 is configured to extend from and / or be attached to the ends 718 of the anchoring arms 714.

[0072] Although upper barrier 704 is shown as having a generally flat structure, upper barrier 704 may have any shape and / or size. For example, upper barrier 704 may have a generally wavy structure, where high points (i.e., peaks) of upper barrier 704 are configured to fit over proximal portions 716 of the anchoring arms and low points (i.e., valleys) are configured to be near and / or press against tissue wall 708. In some embodiments, upper barrier 704 may be comprised of a generally flexible and / or resilient material such that upper barrier 704 fits snugly over anchoring arms 714 and / or central flow portion 702 and / or may be configured to at least partially flex around portions of anchoring arms 714 and / or central flow portion 702 to minimize gaps around and / or within anchoring arms 714 and / or central flow portion 702. For example, the upper barrier 704 may have a generally flexible structure and / or may be configured to approximate the contours and / or general shape of the anchoring arms 714 and / or central flow portion 702 when placed and / or positioned over the anchoring arms 714 and / or central flow portion 702. In some embodiments, the upper barrier 704 may be structurally rigid enough to at least partially resist growth and / or expansion of the tissue wall 708.

[0073] 8A and 8B show a shunt 800 having a lower barrier 804 for preventing, containing, reducing, and / or inhibiting tissue growth, according to some embodiments. FIG. 8A shows a side view of the shunt 800, and FIG. 8B shows a view of the shunt 800 from above (e.g., from the left atrium). In some embodiments, the lower barrier 804 may have an elliptical and / or torus shape. The lower barrier 804 may form a complete ring around a central hole, which may be aligned with a flow path formed and / or maintained by the central flow portion 802 of the shunt 800. For example, the central flow portion 802 may define a flow path through a tissue wall 808, and the upper barrier 804 may be configured to surround but not obstruct (or only partially obstruct) the flow path.

[0074] 8A shows a cross-sectional view of the shunt 800, with the lower barrier 804 shown as having a partial elliptical shape. However, the lower barrier 804 may form a complete ellipse around the opening in the tissue wall 808. The lower barrier 804 may have any shape. For example, the lower barrier 804 may have a rectangular, triangular, pentagonal, octagonal, or other shape and / or may include a hole in the center of the lower barrier 804 to allow flow through it.

[0075] The lower barrier 804 may be configured to be positioned between the one or more anchoring arms 814 and the tissue wall 808. For example, the one or more anchoring arms 814 may be configured to press the lower barrier 804 against the tissue wall 808. Although the lower barrier 804 is shown as having a generally thin structure, the lower barrier 804 may have any thickness. Furthermore, the lower barrier 804 may have a variable thickness. For example, the lower barrier 804 may have an at least partially rounded surface, in which case the cross section of the lower barrier 804 has an elliptical shape similar to a torus.

[0076] In some embodiments, the lower barrier 804 may be configured to extend from and / or be attached to the central flow portion 802 and / or one or more anchoring arms 814 of the shunt 800. For example, the lower barrier 804 may be attached to and / or extend from the first anchoring arm 814a and / or the second anchoring arm 814b. The first anchoring arm 814a and the second anchoring arm 814b may be located generally on opposite sides of an opening 811 on the first surface 801 of the tissue wall 808 (or the second surface 803 of the tissue wall 808). In some embodiments, the central flow portion 802 and / or the anchoring arms 814 may be configured to hold the lower barrier 804 in place by pressing the lower barrier 804 against the tissue wall 808. Additionally or alternatively, the lower barrier 804 may have various elements configured to interact with the tissue wall 808 and hold the lower barrier 804 in place. For example, the outer surface of the lower barrier 804 may have raised and / or contoured structures configured to grip and / or penetrate the surface of the tissue wall 808. In another example, the lower barrier 804 may comprise one or more nails, screws, hooks, barbs, and / or other elements configured to attach to and / or penetrate the tissue wall to firmly hold the lower barrier 804 in place. In some embodiments, the anchoring elements (e.g., nails, screws, hooks, barbs) for anchoring the lower barrier 804 to the tissue wall 808 may be delivered separately.

[0077] 8A and 8B show only a single lower barrier 804, the shunt 800 may include multiple lower barriers 804. For example, the shunt 800 may include a second lower barrier 804 that presses against the second surface 803 of the tissue wall 808. The lower barrier 804 may have a structure that is sufficiently rigid to oppose and / or resist tissue growth at and / or around the lower barrier 804.

[0078] Delivery Process 9 is a flow diagram of an example process 900 for delivering and / or anchoring a shunt to a human body according to some embodiments. Process 900 includes, at block 902, forming an opening in a tissue wall. As described herein, the opening may be formed by using one or more of a guidewire, a puncture catheter, an introducer sheath, a puncture sheath, and / or a puncture expander. The opening may form a blood flow path between two anatomical chambers (e.g., the left atrium and the coronary sinus). The opening may be formed in any of a variety of ways. One exemplary method is as follows:

[0079] A guidewire may first be advanced from the right atrium and fed into the coronary sinus, for example, through the ostium or opening of the coronary sinus. A catheter may be advanced along the guidewire. The catheter may be introduced into the body through the proximal end of an introducer sheath. The introducer sheath may allow access to a specific vascular pathway (e.g., the jugular vein or subclavian vein) and may have a hemostatic valve therein. The surgeon can manipulate the puncture catheter to the implantation site while holding the introducer sheath in a fixed position. A puncture sheath having a puncture needle with a sharp tip may be advanced along the catheter to puncture the wall and insert into, for example, the left atrium. A puncture expander may be advanced along the guidewire to penetrate the tissue wall and insert into the left atrium. The puncture expander may be, for example, an elongated inflatable balloon. The puncture expander may expand radially outward to widen the puncture hole through the tissue wall. In some embodiments, the opening may have a generally circular shape.

[0080] The implant may be delivered through the lumen of the catheter. During delivery, the implant may be in a collapsed configuration to facilitate delivery. For example, the implant may be bent, twisted, and / or otherwise formed to have a minimal profile to facilitate delivery through the catheter. The implant may be positioned within the annular space between the inner and outer sheaths of the catheter. The inner sheath may be retracted to position the implant in snug engagement with the tissue wall. Radiopaque markers may be provided to facilitate placement of the catheter and / or shunt. By forming an opening between the left atrium and the coronary sinus, blood can flow from the left atrium (typically >8 mmHg) to the coronary sinus (typically <8 mmHg). One or more implants may be delivered to and / or anchored to the first and / or second surfaces of the tissue wall 808.

[0081] At block 904, process 900 may include preparing a region of tissue around the opening. In some embodiments, preparing the tissue may include cauterizing, scarring, and / or otherwise treating the tissue to prevent, inhibit, and / or contain tissue growth in and / or around this region of tissue. In some embodiments, the treated region may completely surround the opening in the tissue wall. For example, the treated region may form a circular (or other shaped) region around the opening so that tissue growth around the entire opening can be managed.

[0082] The process 900 includes, at block 906, attaching a shunt to a delivery catheter. The shunt may be crimped and / or collapsed onto the exterior surface of the catheter and / or within the lumen of the delivery catheter during delivery. In some embodiments, the shunt may be configured to reside between the exterior surface of the catheter and a delivery sheath configured to at least partially cover the shunt. The sheath may be configured to at least partially prevent expansion of the shunt during delivery through various pathways in the body.

[0083] Process 900 includes advancing a delivery catheter to and / or near the opening at block 908. In some embodiments, the shunt may be configured to be at least partially curved to facilitate delivery to and / or near the opening. For example, the catheter and shunt may be at least partially curved to manipulate the catheter into the coronary sinus ostium and / or opening.

[0084] Process 900 includes placing a shunt within and / or around the opening at block 910. For example, the shunt may include a flow portion and / or tubing configured to be positioned within the opening and / or one or more anchoring mechanisms configured to anchor the flow portion to a portion of the tissue wall outside the opening. In some embodiments, the shunt may include various barriers configured to prevent, inhibit, reduce, and / or contain tissue growth around the opening and / or around the shunt.

[0085] Additional Embodiments Depending on the embodiment, some acts, events, or functions of any of the processes or algorithms described herein may be performed in a different sequence, added, combined, or omitted entirely. Thus, in some embodiments, not all described acts or events are required to implement a process.

[0086] In particular, conditional terms used herein, such as "can," "could," "may," "may," "for example," and the like, are intended to have their ordinary meaning unless otherwise indicated or understood otherwise within the context in which they are used, and are generally intended to indicate that some embodiments include certain features, elements, and / or steps, and other embodiments do not include those features, elements, and / or steps. Thus, such conditional terms generally do not imply that features, elements, and / or steps are required for one or more embodiments, nor do they imply that one or more embodiments necessarily include logic for determining, with or without authorial input or direction, whether those features, elements, and / or steps are included in any particular embodiment or whether those features, elements, and / or steps should be performed in any particular embodiment. Terms such as "comprise," "include," "have," and the like are synonymous and used in their ordinary sense, and are used in an open-ended, inclusive manner and do not exclude additional elements, features, acts, operations, etc. Furthermore, the term "or" is used in an inclusive sense (and not an exclusive sense), whereby when the term is used, for example, to connect a list of elements, the term "or" means one, some, or all of the elements in the list. Connective language such as "at least one of X, Y, or Z" is understood to be used within the context of its general use to indicate that an item, term, element, etc., can be either X, Y, or Z, unless otherwise indicated. Thus, such connective language does not generally imply that a particular embodiment requires that at least one X, at least one Y, and at least one Z each be present.

[0087] In the foregoing description of embodiments, it should be appreciated that various features may be grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. However, this method of disclosure should not be interpreted as reflecting an intention that any claim requires more features than are expressly recited in that claim. Moreover, any component, feature, or step illustrated and / or described in a particular embodiment herein may be applied to or used in conjunction with any other embodiment. Furthermore, no component, feature, step, or group of components, features, or steps is necessary or essential to each embodiment. Accordingly, the scope of the invention as disclosed herein and claimed below is not intended to be limited by the specific embodiments described above, but rather should be determined solely by a fair reading of the following claims.

[0088] It should be understood that some ordinal numbers (e.g., "first" or "second") are provided for ease of reference and do not necessarily imply physical characteristics or order. Thus, herein, ordinal numbers (e.g., "first," "second," "third," etc.) used to modify an element, such as a structure, component, or operation, do not necessarily indicate a priority or order of that element relative to any other elements, but generally distinguish that element from another element having a similar or identical name (for the purposes of using the ordinal number). Furthermore, herein, indefinite articles ("a" and "an") may indicate "one or more" rather than "one." Furthermore, an action performed "based on" a condition or event may be performed based on one or more other conditions or events not explicitly stated.

[0089] Unless otherwise specified, all terms (including scientific and technical terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the exemplary embodiments belong. Terms as defined in commonly used dictionaries should be understood to have a meaning consistent with the meaning of the term in the context of the relevant art, and should not be construed in an idealized or overly formal sense unless explicitly defined.

[0090] Although several preferred embodiments and examples are disclosed below, the subject matter of the present invention extends beyond the explicitly disclosed embodiments to other alternative embodiments and / or alternative uses, as well as modifications and equivalents thereof. Accordingly, the scope of claims that may arise from the above embodiments is not limited by any of the specific embodiments described below. For example, in any method or process disclosed herein, the acts or operations of the method or process may be performed in any suitable sequence and are not necessarily limited to any particular sequence disclosed. Although various operations may be described as multiple discrete operations as may be useful in understanding some embodiments, the order of description should not be construed to imply that these operations are order dependent. Furthermore, structures, systems, and / or devices described herein may be embodied as integrated components or as separate components. For purposes of comparing various embodiments, several aspects and advantages of these embodiments will be discussed. It is not necessarily the case that all such aspects or advantages are achieved by any particular embodiment. Thus, for example, various embodiments may be implemented to achieve or optimize one advantage or group of advantages taught herein without necessarily achieving other aspects or advantages that may also be taught or suggested herein.

[0091] Spatially relative terms such as "outside," "inside," "top," "bottom," "lower," "upper," "vertical," "horizontal," and similar terms may be used herein for ease of description when describing the relationship between one element or component and another element or component illustrated in the figures. It should be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation, as well as the orientation shown in the figures. For example, if a device illustrated in the figures were turned over, a device positioned "below" or "below" another device might be positioned "above" the other device. Thus, the exemplary term "below" may include both a lower position and an upper position. Devices may be oriented in other directions, and thus the spatially relative terms may be interpreted differently depending on the orientation.

[0092] Unless expressly stated otherwise, comparison and / or quantitative terms such as "less," "more," "greater than," etc. are intended to encompass the concept of equivalence. For example, "less" can mean "less than" in the strictest mathematical sense as well as "less than or equal to."

[0093] The delivery systems described herein may be used to position catheter tips and / or catheters in various regions of the human heart. For example, the catheter tip and / or catheter may be configured to travel from the right atrium to the coronary sinus. However, the description may also refer to or generally apply to positioning the catheter tip and / or catheter from a first body cavity or lumen to a second body cavity or lumen, with the understanding that the catheter tip and / or catheter may be bent as it is positioned from the first body cavity or lumen into the second body cavity or lumen. A body cavity or lumen may refer to any of several fluid channels, blood vessels, and / or organ cavities (e.g., heart chambers). Furthermore, references herein to a “catheter,” “tube,” “sheath,” “steerable sheath,” and / or “steerable catheter” may refer to or generally apply to any type of elongated tubular delivery device with an inner lumen configured to slidably receive an instrument, such as an elongated tubular delivery device for placement within the atrium or coronary sinus, including, for example, a delivery catheter and / or cannula. It will be appreciated that other types of medical implant devices and / or procedures can be delivered to the coronary sinus using the delivery systems described herein, including, for example, ablation therapy, drug delivery, and / or coronary sinus lead placement. [Explanation of symbols]

[0094] 1. Heart 2 left atrium 5 Right atrium 10 Implants 11 Subclavian vein 12 carotid artery 13 femoral vein 14. Inferior vena cava 15 Superior vena cava 16 Catheter 19 Coronary sinus 301 First Side 303 Second Side 308 Organization Wall 311 Opening 350 Delivery Catheter 352 Distal tip 400 Shunt 401 First Side 402 Central flow section 403 Second Side 404 Wall 404a First Wall 404b Second Wall 404c The Third Wall 404d The Fourth Wall 406 Ring 408 Organization Wall 410 Longitudinal Axis 412 Second Angle 414 Fixed Arm 414a First fixing arm 414b Second fixing arm 416 Thickness 418 width 420 length 500 shunts 501 First Side 502 Central flow section 503 Second Side 504 Barrier Spike 505 base 506 Ring 507 End 508 Organization Wall 514 Fixed arm 604 area 608 Organization Wall 609 First Radius 610 Second Radius 611 Opening 612 Gap 701 Shunt 702 Central flow section 703 Second Side 704 Upper Barrier 708 Organization Wall 714 Fixed Arm 716 Proximal end 718 End 800 shunts 801 First Side 802 Central flow section 803 Second Side 804 Lower Barrier 808 Organization Wall 814 Fixed arm 814a First fixing arm 814b Second fixing arm

Claims

1. a central flow section configured to at least partially fit within and maintain an opening in a tissue wall, the tissue wall being located between a first anatomical chamber and a second anatomical chamber, the opening forming a blood flow path between the first anatomical chamber and the second anatomical chamber; a barrier configured to alter tissue growth around the shunt; A shunt comprising:

2. The shunt of claim 1 , further comprising one or more anchoring arms extending from the central flow section, the one or more anchoring arms configured to anchor to the tissue wall.

3. The shunt of claim 2 , wherein the barrier extends from at least one of the one or more anchoring arms.

4. The shunt of claim 3 , wherein the barrier comprises one or more spikes extending from at least one of the one or more anchoring arms.

5. The shunt of claim 4 , wherein the one or more spikes have pointed ends.

6. 6. The shunt of claim 4 or 5, wherein the barrier comprises a first spike and a second spike, the first spike being configured to be located farther from the opening than the second spike.

7. 7. The shunt of claim 1, wherein the barrier extends from the central flow section.

8. 8. The shunt of claim 1, wherein the barrier comprises a first portion configured to extend across a first surface of the tissue wall.

9. 9. The shunt of claim 8, wherein the first portion is configured to extend across the first surface of the tissue wall at an angle of approximately 45 degrees.

10. 10. The shunt of claim 8 or 9, wherein the barrier comprises a second portion configured to extend across a second surface of the tissue wall.

11. The shunt of claim 10 , wherein the first portion and the second portion form a single, continuous device.

12. 12. The shunt of claim 8, wherein the opening has an elliptical shape, the first portion forms at least a partial cone having a tapered elliptical shape, and the first portion extends across a complete ellipse of tissue on the first surface of the tissue wall.

13. The shunt of claim 12 , wherein the first portion does not extend across the opening.

14. 14. The shunt of any one of claims 8 to 13, wherein the length of the first portion is greater than the width and thickness of the first portion.

15. 15. The shunt of any one of claims 8 to 14, wherein the first portion has the shape of at least a partial elliptical ring configured with a hollow center aligned with the opening.

16. 16. The shunt of claim 15, further comprising one or more anchoring arms extending from the central flow section, the one or more anchoring arms configured to anchor to the tissue wall.

17. 17. The shunt of claim 16, wherein the barrier extends from at least one of the one or more anchoring arms.

18. 18. The shunt of claim 16 or 17, wherein the barrier is configured to be located between the one or more anchoring arms and the tissue wall.

19. 19. The shunt of any one of claims 1 to 18, wherein the central flow section is further configured to prevent tissue ingrowth within the opening.

20. 20. The shunt of any one of claims 1 to 19, wherein the central flow section is configured to expand in response to expansion of the tissue wall.

21. forming an opening in a tissue wall; treating an area of ​​tissue around the opening to prevent tissue ingrowth in the opening; and placing a shunt in the opening.

22. 22. The method of claim 21, wherein the region of tissue has an oval shape and completely surrounds the opening.

23. 23. The method of claim 21 or 22, wherein the shunt comprises a central flow portion configured to fit at least partially within and maintain an opening in a tissue wall, the tissue wall being located between a first anatomical chamber and a second anatomical chamber, the opening forming a blood flow path between the first anatomical chamber and the second anatomical chamber.

24. 24. The method of claim 23, wherein the shunt further comprises a barrier configured to alter tissue growth around the shunt.

25. 25. The method of any one of claims 21 to 24, wherein treating the area of ​​the tissue comprises calcining the area of ​​the tissue.

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