CA2854571C

CA2854571C - Devices, systems and methods to treat heart failure

Info

Publication number: CA2854571C
Application number: CA2854571A
Authority: CA
Inventors: David Celermajer; Edward Mcnamara; Stephen Forcucci; Hiroatsu Sugimoto
Original assignee: Corvia Medical Inc
Current assignee: Corvia Medical Inc
Priority date: 2009-04-28
Filing date: 2010-03-08
Publication date: 2017-02-28
Anticipated expiration: 2030-03-08
Also published as: CA2854571A1; CA2998009A1; CA2998009C

Abstract

Several unique intracardiac pressure vents, placement catheters, methods of placement and methods of treating heart failure are presented. The intracardiac pressure vents presented allow sufficient flow from the left atrium to the right atrium to relieve elevated left atrial pressure and resulting patient symptoms but also limit the amount of flow from the right atrium to the left atrium to minimize the potential for thrombus or other embolic material from entering the arterial circulation. Deployment of the interatrial pressure vent preferably occurs in a series of steps comprising first advancing the placement catheter through the septal opening, second deploying a first flange, third retracting the placement catheter to position the first flange against the septal wall, and fourth deploying a second flange on the other side of the septal wall from the first flange.

Description

W() 2010/129089 TITLE:
DEVICES, SYSTEMS AND METHODS TO TREAT HEART FAILURE
FIELD OF THE INVENTION

[0002] The present invention relates generally to devices and methods for treating heart failure. In particular, the invention relates to interatrial pressure vents, shunts and the like, which reduce elevated pressure on one side of the heart thus mitigating the symptoms that result, as well as placement devices, systems, and methods therefore.
BACKGROUND OF THE INVENTION

[0003] Heart failure is a common and potentially lethal condition affecting humans, with sub-optimal clinical outcomes often resulting in symptoms, morbidity and/or mortality, despite maximal medical treatment. In particular, "diastolic heart failure" refers to the clinical syndrome of heart failure occurring in the context of preserved left ventricular systolic function (ejection fraction) and in the absence of major valvular disease. This condition is characterized by a stiff left ventricle with decreased compliance and impaired relaxation, which leads to increased end-diastol ic - I -pressure. Approximately one third of patients with heart failure have diastolic heart failure and there are very few, if any, proven effective treatments.
100041 Symptoms of diastolic heart failure arc due, at least in a large part, to an elevation in pressure in the left atrium. In addition to diastolic heart failure, a number of other medical conditions, including systolic dysfunction of the left ventricle and valve disease, can lead to elevated pressures in the left atrium. Increased left atrial pressure often causes acute or chronic breathlessness amongst other problems.
In addition, a variety of heart conditions can lead to "right heart failure", which can result in enlargement of the liver (hepatomegaly), fluid accumulation in the abdomen (ascitcs) and/or swelling of the lower limbs.
100051 Frequently, patients with diastolic heart failure experience breathlessness due, in part, to elevated pulmonary venous pressure. These patients often feel worse when supine than when sitting or standing, implying that small changes in pulmonary venous pressure have a pronounced effect on symptoms.
[00061 In the past, strategies have been described for the relief of high pressure in the right atrium, such as thc creation of hole(s) in the native or surgically created septum between the left and right atria. These have been designed for the rare conditions of pulmonary hypertension or cavopulmonary connections for certain complex congenital heart diseases.
100071 Accordingly, there exists a need for devices and methods to treat heart failure particularly diastolic and/or systolic failure of the left ventricle and its consequences.
[00081 Furthermore, there also still exists a need for devices to relieve high pressure in the left atrium and which will prevent or minimize the chance of the passage of thrombi, especially from the right atrium to the left atrium, and the resulting risk of systemic emboli.
SUMMARY OF INVENTION
100091 It is, therefore, a goal of this invention to effect a reduction in pulmonary venous pressure to case symptoms of diastolic heart failure. It is a further goal of this invention to create a controlled vent between the left atrium and right atrium to allow a sufficient amount of blood to pass from the left atrium to the right atrium but minimize blood flow from the right atrium to the left atrium.
100101 It is a further goal of this invention to create a controlled vent that will respond to pressure differences between the left and right atrium.

It is a furthcr goal of this invention to provide an interatrial pressure venting device that prevents thrombi from entering the left atrium.
100111 Thc present invention solves these and other needs by providing a venting device, which in some embodiments comprises a controlled opening or an extended tubular opening, between the left atrium and right atrium that allows an amount of.
blood to vent from thc left heart to the right heart, thereby reducing left atrial pressure and thc symptoms associated with diastolic heart failure.
100121 Several unique intracardiac pressure vents, placement catheters, methods of placement and methods of treating heart failure are presented. The intracardiac pressure vents presented allow sufficient flow from the left atrium to the right atrium to relieve elevated left atrial pressure and resulting patient symptoms but also limit the amount of flow from the right atrium to the left atrium to minimize the potential for thrombi or other embolic material from entering the arterial circulation.
100131 In addition, the intracardiac pressure vents presented solve the problem of controlling flow in one direction but minimizing flow in another direction with very low changes in pressure across the device.
100141 Also, thc intracardiac pressure vents presented solve the problem of reducing calcium deposition, protein deposition and thrombi formation in a low pressure environment.
100151 Furthermore, the intracardiac pressure vents presented solve the problem of damage to the interatrial septum as well as the rest of thc left atrium from excessive pressure against the wall which can cause injury to the tissue and possibly adverse reaction by the patient or compromised function to the interatrial pressure vent.
100161 In addition, atrial arrhythmias are frequently seen in patients with heart failure and may, in part, be caused by chronically elevated left atrial pressure.
Therefore, relief of elevated left atrial pressure may lead to reduction of atrial fibrillation.
100171 The present invention provides interatrial pressure vents, placement catheters, methods for placing a device in the interatrial septum within the heart of a patient and methods for treatment of the symptoms of heart failure, particularly diastolic heart failure.
100181 In embodiments, the interatrial pressure vent comprises a body assembly and a flow control element; the body assembly comprises a flexible, substantially open mesh adapted for use in a patient. The flow control element attaches to at least one point of the body assembly and the flow control clement provides greater resistance to flow in one direction than it does in another dircction.
100191 In embodiments, the interatrial pressure vent comprises a body assembly and a flow control element; thc body assembly comprises a flexible, substantially open mesh adapted for use in a patient. The flow control clement attaches to at least one point of thc body assembly and is at least partially open to flow when there is no pressure differential across the flow control element.
100201 In embodiments, the interatrial pressure vent comprises a body assembly and a flow control element; thc body assembly comprises a core segment and at least one flange segment; the flange segment is integral with, or attached to at least one point adjacent to, an end of the core segment; the flange segment extends radially outward from thc center longitudinal axis of the core segment. The flow control element attaches to at least one point along the core segment and the flow control element provides greater resistance to flow in one direction than in the opposite direction.
100211 In embodiments, the interatrial pressure vent comprises a body assembly and a flow control element; the body assembly comprises a substantially cylindrical core segment and at least one flange segment; the flange segment is integral with, or attached at least to onc point adjacent to, an cnd of the core segment; thc flange segment extending radially outward from the center longitudinal axis of the core segment. The flow control element attaches to at least one point along the core segment and the flow control element provides greater resistance to flow in one direction than anothcr direction.
100221 In embodiments, the interatrial pressure vent comprises a body assembly and a flow control element. The body assembly comprises a substantially cylindrical core segment and at least one flange segment integral with, or attached to at least onc end of, the core segment; thc flange segment extending radially outward from the axis of the core segment. The flow control element attaches to at least one point along the core segment and the flow control element is at least partially open to flow when there is no pressure differential across the flow control element.
100231 In embodiments, the interatrial pressure vent comprises a body assembly and a flow control clement. The body assembly comprises a substantially cylindrical core segment and at least one flange segment integral with, or attached to at least one end of, the core segment and extedning away from the axis of thc core segment.
The

- 4 -HOW control element attaches to at least one point along the flange assembly and provides greater resistance to flow in onc direction than the other direction.
100241 In embodiments, the interatrial pressure vent comprises a body assembly and a flow control element. The body assembly comprises a substantially cylindrical core segment and at least one flange segment integral with, or attached to at least one end of, the core segment and extending away from thc axis of the core segment.
The flow control element attaches to at least one point along thc flange assembly and is at least partially open to flow when there is no pressure differential across the flow control element.
100251 In embodiments, the interatrial pressure vent comprises a body assembly and a flow control element. The body assembly comprises a substantially cylindrical core segment and at least one flange segment integral with, or attached to at least one end of, the core segment and extending away from the axis of the core segment.
The flow control element extends at least partly onto the flange assembly and creates a sealable contact to the atrial septum and provides greater resistance to flow in one direction than the other direction.
10026J In embodiments, the interatrial pressure vent comprises a body assembly and a flow control element. The body assembly comprises a substantially cylindrical core segment and at least one flange segment integral with, or attached to, at least one end of the core segment and extends away from the axis of the core segment.
The flow control element attaches to thc flange assembly and creates a sealable connection to the atrial septum and is at least partially open to flow when there is no pressure differential across the flow control element.
100271 In embodiments, the interatrial pressure vent comprises a body assembly with a first end and a second end and a flow control element; the body assembly comprises a core segment including at least one flange segment integral with, or attached to, at least one point adjacent to the first end of the core segment and at least one other flange segment integral with, or attached to, at least one point adjacent to thc second end of the corc segment; the flange segments extending radially outward from the center longitudinal axis of the core segment and thc flange segments oriented so they do not oppose each other when deployed. The flow control element attaches to at least one point along the core segment and the flow control element provides greater resistance to flow in one direction than it does in another direction.

- 5 -100281 In embodiments, thc interatrial pressure vent comprises a body assembly with a first end and a second end and a flow control clement; the body assembly comprises a core segment including at least one flange segment integral with, or attached to, at least one point adjacent to the first end of the core segment and at least one other flange segment integral with, or attached to, at least one point adjacent to the second end of the core segment; the flange segments extending radially outward from the center longitudinal axis of the core segment and the flange segments oriented so they do not oppose each other when deployed. The flow control element attaches to at least one point along the core segment and the flow control element is at least partially open to flow when there is no pressure differential across the flow control element.
100291 In embodiments, the intcratrial pressure vent comprises a body assembly with a first end and a second end and a flow control element comprised of at least one leaflet; the body assembly comprises a substantially cylindrical core segment and a number of flange segments integral with, or attached to, at least one point on each side of the body segment and extending radially outward from thc center longitudinal axis of the core segment; thc number of flange segments on either side of thc core segment being a whole multiple of the number of leaflets.
100301 In embodiments, the interatrial pressure vent comprises a body assembly with a first end and a second end and a flow control element comprised of at least one leaflet; the body assembly comprises a substantially cylindrical core segment and a number of flange segments integral with, or attached to, at least one point on each side of the body segment and extending radially outward from the center longitudinal axis of thc core segment; the number of flange segments being a whole multiple of the number of leaflets. The flow control clement attaches to at least one point of the body assembly and the flow control element provides greater resistance to flow in one direction.than another direction.
100311 In embodiments, the interatrial pressure vent comprises a body assembly with a first end and a second end and a flow control element comprised of at least one leaflet; the body assembly comprises a substantially cylindrical core segment and a number of flange segments integral with, or attached to, at least one point on each side of the body segment and extending radially outward from the center longitudinal axis of the core segment; the number of flange segments being somc multiple of the number of leaflets. The flow control element attaches to at least one point of the body

- 6 -assembly and is at least partially open to flow when there is no pressure differential across the flow control element.
100321 In embodiments, an implant system comprises an interatrial pressure vent and placement catheter for treating heart failure. The implant system is comprised of a body assembly and a flow control clement. The body assembly is comprised of a substantially cylindrical core segment and at least one flange segment integral with, or attached to, at least one end of the core segment and extending radially away from the core segment. The flow control element is attached to at least onc point along the core segment and provides greater resistance to flow in onc direction than the other direction. Thc placement catheter is comprised of an inner shaft and an outer shaft.
The inner shaft comprises an elongate tube and a handle component. The inner shaft also contains at least one lumen that extends along at least part of thc length of the inner shaft. The outer shaft comprises an elongate hollow tube or sheath and a different handle component that slideably interfaces with thc first handle component.
100331 In embodiments, an implant system comprises and interatrial pressure vent and placement catheter for treating heart failure. The implant system is comprised of a body assembly and a flow control element. The body assembly is comprised ()fa substantially cylindrical core segment and at least one flange segment integral with, or attached to, at least one end of the body assembly and extending radially away from the body segment. The flow control element is attached to at least one point along a flange and provides greater resistance to flow in one direction than the other direction.
The placement catheter is comprised of an inner shaft and an outer shaft. Thc inner shaft comprises an elongate tube and a handle component. The inncr shaft also contains at least one lumen that extends along at least part of the length of the inner shaft. The outer shaft comprises an elongate hollow tube (or sheath) and a different handle component that slideably interfaces with the first handle component.
100341 In embodiments, an implant system comprises and interatrial pressure vent and placement catheter for treating heart failure. The implant system is comprised of a body assembly and a flow control element. The body assembly is comprised of a substantially cylindrical core segment and at least one flange segment integral with, or attached to, at least onc end of thc body assembly and extending radially away from the body segment. The flow control clement is attached to at least one point along a flange and provides greater resistance to flow in one direction than the other direction.
The placement catheter is comprised of an inner shaft and an outcr shaft. The inner

- 7 -shaft comprises an elongate tube with at least one flange or circumferential groove formed in the outer diameter and a handle component. The inner shaft also contains at least one lumen that extends along at least part of the length of the inner shaft. The outer shaft comprises an elongate hollow tube (or sheath) and a different handle component that slideably interfaces with the first handle component.
100351 In other embodiments, the invention comprises a device for treating a heart condition in a patient comprising a body element having a core segment defining a passage, a first annular flange comprising a plurality of flange segments, and a second annular flange comprising a plurality of flange segments. In embodiments, at least a portion of one of the flange segments is either more or less flexible than the remaining portion of the flange segment or other portions of the body element, including but not limited to the cylindrical core segment.
100361 In other embodiments, the device comprise a third or intermediate annular flange for better adherence to the septa! wall.
[00371 In other embodiments, the device comprises a flow control clement configured to aim the flow of blood in a desired direction.
100381 In other embodiments, thc invention is configured to be more easily retrieved during deployment. Such embodiments can include among other elements a at least one extended flange segment in one of the annular flanges that is able to be retained within a placement catheter when the other portions of the device are deployed.
100391 In embodiments, the method of placing the interatrial pressure vent into position may comprise a sequence of steps to locate and gain access, to a vascular channel leading to the heart, placing an introducer catheter via this channel into one of the atriums of the heart, locating the interatrial septum between the left and right atriums, creating an opening in the interatrial septum, advancing a placement catheter containing an interatrial pressure vent into one of thc atriums and then through the opening created in the interatrial septum between the right and left atriums, and then controllably deploying the interatrial pressure vent so it is securably connected to the interatrial septum.
[00401 Deployment of the interatrial pressure vent preferably occurs in a series of steps comprising first advancing the placement catheter through thc scptal opening, second deploying a first flange, third retracting the placement catheter to position the first flange against the septal wall, and fourth deploying a second flange on the other side of thc scptal wall from the first.flange.

- 8 -

9 100411 In embodiments where the device disclosed herein is implanted into the atrial septum, the introducer catheter may be placed through the inferior vena cava via a femoral vein to the right atrium.
100421 Other pathways arc available including placing the introducer catheter through the superior vena cava via a jugular vein; through the aorta, via a femoral artery, past the aortic valve and into the left atrium; through the aorta, via a brachial artery, past thc aortic valve and into the left atrium; through the superior vcna cava via a basilica vein; through the superior vena cava via a cephalic vein;
intraoperatively, through an opening created in the right atrium either for this reason or during a procedure performed for some other purpose; intraoperatively through an opening created in the left atrium either for this reason or during a procedure performed for some other reason; or via a guidewire that is positioned through the interatrial septum and located in the pulmonary artery.
100431 Regarding the placement catheter, in some embodiments the placement catheter is designed to function as thc introducer catheter and the placement catheter, eliminating thc need for a catheter exchange. While in other embodiments, the introducer catheter, the placement catheter, or both arc constructed to be exchanged over only part of thcir length to avoid the necessity of handling a guidewire that is at least twice as long as the catheter. Still in other embodiments, the introducer catheter or the placement catheter, or both has a pre-shaped curve to enable orientation of the placement catheter substantially orthogonal to the septal wall. The catheter may be curved between 30 and 45 away from the catheter axis at a point between 5 and 15 centimeters away from the distal end of the placement catheter.
100441 In embodiments of the invention where the inventive device is to be placed in the atrial septum, an opening in the septum can be performed using the introducer catheter in a separate procedure from the interatrial pressure vent placement procedure. Access through the opening can be maintained via a wireguide positioned in the right atrium or the pulmonary artery. The opening can be formed using the placement catheter via a distal tip segment that is part of thc placement catheter.
100451 Thc opening may be predilated using a balloon or other dilating device either as part of the procedure described or as a separate procedure.
100461 In another aspect, the opening is formed and dilated as part of a single, unified procedure with the interatrial pressure vent placement procedure. This may be accomplished by integrating a balloon or othcr dilating component as part of thc placement catheter and dilating the opening as part of placing the interatrial pressure vent. For example, this could be accomplished using a balloon that can be folded to achieve a small loaded profile and will have a suitable pressure capacity and suitable durability to dilate the septum opening and the interatrial pressure vent together.
100471 The opening that is fonned in the interatrial septum may be formed by pushing a catheter tip through the septum at the location of septum primum.
Because this septum is normally very thin, the distal tip may be pushed directly through without significant force.
100481 In an alternate method, the opening in the interatrial septum can be formed with a cutting tool that is advanced through the introducer catheter or the placement catheter. The tool preferably comprises a blade and a shaft. The blade contains at least two surfaces and one edge. The edge is sharpened and formed at an angle so that the blade slices as it is advanced into and through the septum.
100491 In yct another method, the opening in the interatrial septum can be formed with a cutting tool that is advanced through the introducer catheter or thc placement catheter. rlhe tool preferably comprises a blade and a shaft. Thc blade contains at least two surfaces and two separate edges that arc sharpened at an angle so that the blade slices as it is advanced into and through the septum and the septum is cut generally in an x shaped opening.
100501 In yet another method, thc opening in the interatrial septum can be formed with a punching tool that is advanced through the introducer catheter or the placement catheter. The punching tool preferably comprises a cutting assembly and a shaft. The cutting assembly preferably comprises a hollow, conical shape with a sharpened edge along the base circumference. The cutting assembly is connected at least to one point on the shaft and is generally oriented so the apex of the cone is pointed away from the shaft.
[00511 In one method, the cutting assembly can be operated by advancing the conical assembly through the interatrial septum and then pulling it back to form an opening that is generally circular.
100521 In another method, the cutting assembly can be operated by advancing thc conical assembly through the interatrial septum and then rotating it as it is pulled pack to create a circular cutting action against the interatrial septum.
100531 In another embodiment, the cutting tool can be formed of at least one cutting member and one shaft. The cutting member is connected at least to one point

- 10 -along the shaft and the other end of the cutting member is adjustably positioned so it can lay alongside the shaft or at some angle away from the shaft. To place the cutting tool, the cutting member is placed alongside the shaft and then advanced through the septum. Then the cutting member would be adjusted to a second position, radially further away from the shaft than the first position, and the shaft would be positioned so the cutting member exerts lateral stress against the septum. The cutting member could be designed to slice the septum in this manner. In another method, the cutting tool could be rotated once thc shaft and cutting member were repositioned so the slicing motion would cut a generally circular hole through the septum.
100541 In embodiments, the cutting member is round wire.
100551 In another embodiment, the cutting member can be connected to one output of a power supply, capable of supplying a suitable signal to the cutting member, the other output of which is connected to a ground plate placed against thc patient's skin. An appropriate electric potential can be placed between the cutting member and ground plate to cause a concentrated current density near the wire to aid in cutting through the septum tissue.
100561 In another embodiment, the cutting member is a section of tubing sliced lengthwise and appropriately formed to create a cutting edge. During placement, the cutting member is controllably positioned to lie against the shaft as the shaft is advanced through the placement catheter and through the opening created in the interatrial septum. Once positioned, the placement catheter is retracted and the shaft is positioned within the septum. Once positioned in this manner, the cutting member can be controllably adjusted to a second position, radially further away from the shaft than the first position, and the shaft positioned so the cutting member exerts lateral stress against the septum.
100571 In yet another method, an opening is created in the interatrial septum which is smaller than the diameter of the outer surface of the body of the interatrial pressure vent according to the present invention such that, when the interatrial pressure vent is initially deployed within the interatrial septum, there is some compression from the septum against the body of the interatrial pressure vent.
100581 Referring now to the placement catheter used to position and controllably place the interatrial pressure vent; in one aspect, thc placement catheter consists ()fan inner member and an outer member.

- 11 -PCT/ll S2010/026574 100591 In embodiments, the outer member is comprised of a tubing member and a first handle component, the outer shaft is less than about 16 F in diameter and formed of a material suitably smooth and resilient in order to restrain the stowed interatrial pressure vent and allow smooth stowing and deployment, such as PTFE, FEP, Tefzel, PVDF, I IDPE or other suitable materials.
100601 In embodiments, the inner member is comprised of at least one tubing member with an inner lumen through at least part of the tubing member, and a second handle component attached to the proximal end, with the second handle component slideably attached to the first handle component.
100611 In embodiments, the handle components are interconnected via an inclined, helical lever to enable advancement of the inner member relative to the outer member by rotating the outer shaft handle while holding the inner shaft handle.
100621 In embodiments, the handle components comprise a locking mechanism that prevents the handle component from moving in relationship to each other beyond a certain predetermined length 100631 In embodiments, the handle components contain at least two locking mechanisms that prevents the handle component from moving in relationship to each other beyond two different predetermined length 100641 In embodiments, the inner member contains a stiffening element adjacent to the distal arca.
100651 In embodiments, a system for treating heart failure in a patient consists of an interatrial pressure vent and placement device. The interatrial pressure vent comprises a body section and a flow control element. The body section comprises a core section and at least one flange segment. The flange segment comprises a midsection adjacent to the body and an end section that has a greater wall thickness than the midsection. The placement device comprises an inner shaft and an outer shaft. The inner shaft comprises an outside diameter and an internal lumen extending at least partly toward the proximal end from the distal end. The outer shaft contains an outside diameter and an inside diameter. The inner shaft contains a necked portion or circumferential groove along at least part of its length of smaller diameter than at least a portion of the inncr member distal to the necked portion; the space formed between the outside of the necked portion and the inside of the outer shaft being sufficient to contain a folded or otherwise compressed interatrial pressure vent of the present invention and the space formed between the outside of the non-necked portion

- 12 -and the inside of the outer shaft being insufficient to contain the interatrial pressure vent.
[00661 In embodiments, a system for treating heart failure in a patient consists of an interatrial pressure vent and placement device. The interatrial pressure vent comprises a body section and a flow control clement. The body section comprises a core section and at least one flange segment. The flange segment comprises a midsection adjacent to the body and an end section located radially further away than thc midsection and with a larger dimension in thc radial dircction than the midsection.
The placement device comprises an inner shaft and an outer shaft. The inner shaft contains an outside diameter and an internal lumen extending at least partly toward the proximal end from the distal end. The outer shaft contains an outside diameter and an inside diameter. The inner shaft contains a first necked portion or circumferential groove comprising a length and a diameter; the diameter of the first necked portion of thc inner shaft being smaller than at least a portion of the inner member distal to the necked portion and the inner shaft also containing a second necked portion, proximal to the first necked portion and of a length sufficient for containing end section of thc flange segment and a diameter smaller than the first necked portion; the space formed between thc outside of the first necked portion and the inside of the outer shaft being sufficient to contain the folded or otherwise compressed interatrial pressure vent of thc present invention except for thc end section of the flange segment; the space formed between the outside of the non-necked portion and the inside of the outcr shaft being insufficient to contain the interatrial pressure vent and the space formed between the outside of the second necked portion and the inside of the outer shaft being sufficient to contain the end section of the flange segment.
100671 In another aspect, the inner member comprises a first necked portion along at least part of its length of smaller diameter than at least a portion of the inner member distal to the first necked portion and second necked portion, along a second part of its length proximal to the first necked portion and smaller than the first necked portion. The space between the outside of the necked portion and the inside of the outer sheath.
100681 Referring now to the body assembly of the interatrial pressure vent, in one aspect, thc body comprises a core segment and at least one flange segment.

- 13 -100691 In embodiments, thc body assembly comprises a core segment; a first flange comprising at least one flange segment at one end of the core segment;
and a second flange comprising at least one flange segment at the opposite end from the first flange of the core segment.
100701 In embodiments, the body assembly comprises a core segment, comprising a self expanding mesh; a first flange, at one end of the core segment; and a second flange at the opposite cnd of the core segment from thc first flange.
100711 In embodiments, thc body assembly is comprised of a core segment, comprising a balloon expandable mesh; a first flange at one end of the core segment;
and a second flange at the opposite end of thc core segment from the first flange.
100721 In embodiments, the body assembly is comprised of a core segment; a first flange at one end of thc core segment; and a second flange at the opposite end of the core segment from the first flange; each flange oriented to extend substantially radially outward relative to the center axis the flange segment.
100731 In embodiments, the body assembly is comprised of a core segment; a first flange at one end of the core segment; and a second flange at thc opposite end of the core segment from the first flange; each flange oriented to extend substantially radially outward from thc core segment; and at least one flange extending beyond 900 relative to the ccntcr axis of the core segment.
100741 In embodiments, the body assembly is comprised of a core segment; a first flange at one end of the core segment; and a second flan.gc at the opposite end from the first flange of the core segment; each flange oriented to extend substantially radially outward from thc core segment; the first flange formed with a smaller radius of curvature than thc second flange.
100751 In embodiments the interatrial pressure vent comprises a flow control clement biased to allow flow from one atrium of a patient to the other atrium of the patient with lower resistance than in thc reverse direction.
100761 In embodiments the interatrial pressure vent comprises a flow control clement biased that remains at least partially open when there is no pressure differential across the vent.
[0077] In embodiments, the interatrial pressure vent comprises an integral filter to prevent embolic particles larger than about 2mm from passing beyond the filter in the direction of flow.

- 14 -100781 In other embodiments, the interatrial pressure vent comprises a tubular flow element which extends a distance beyond the core segment so as to prevent embolic particles from entering the left atrium.
100791 In embodiments, thc interatrial pressure vent comprises at least one movable flap that responds to pressure changes between the right and left atrium.
[0080i In embodiments, the body assembly may beconstructed from preformed wire braid. The wire braid may beformed from nitinol with a martensite/austenite transition temperature is below 37 C so it remains in its superelastic, austenitic phase during use. The transition temperature is below about 25 -II- 5 C. The wire should have a diameter of at least about 0.0035 (about 2 lbs of breaking strength at 200 ksi tensile). The wire should have a very smooth surface to reduce thrombogenicity or irritation response from the tissue. Thc surface finish may be 63 uin RA or better.
This surface may be obtained either by mechanical polishing, by clectropolishing or a combination. In embodiments, the surface may be cleaned with detergents, acids and/or solvents to remove residual oils or contamination and then controllably passivated to insure minimal corrosion.
[0081] In embodiments, the body assembly may be formed from grade 1 titanium.
In embodiments, the body may be fonned of grade 6 titanium. In embodiments, the body may be formed of grade 9 titanium. In embodiments, thc body may be formed of 316L stainless steel. In embodiments, the body may be formed of 416L stainless steel. In embodiments, the body may be formed of nitinol or Elgiloy. In embodiments, the body is formed of platinum iridium. In embodiments, thc body may be formed of a cobalt chromium alloy. In embodiments, the body may be formed of MI335N. In embodiments, the body may be formed of Vitalium (TRADEMARK). In embodiments, the body may be formed of Ticonium (TRADEMARK). In embodiments, the body may be formed of Stellite (TRADEMARK). In embodiments, the body may bc formed of tantalum. In embodiments, thc body may be formed of platinum. Materials disclosed with reference to the body or any component of the device disclosed herein are not meant to be limiting. The skilled artisan will appreciate that other suitable materials may be used for the body or any other component of the device.
[0082] In embodiments, the body assembly is preferably formed from a length of cylindrical tubing that is precut with slots at specific locations and then formed in a

- 15 -series of processes to produce a shape suited for the purpose of containing a flow control clement within thc interatrial septum.
[00831 As an example, a first process might be to stretch the cylinder to expand its internal diameter to a uniform target dimension. This can be done with a balloon or a standard tubing expander consisting of a segmented sleeve and tapered conical inserts that increase the diamcter of the sleeve when the cones arc advanced toward the center. In order that the shape of the stretched tubing be preserved, thc cylinder should be annealed while held into this stretched shape by heating it beyond 3000 to 600 for at least about 20 minutes to allow the internal stresses to be relieved. A
second process might be to form one flange end shape using a similar process as the first process but using a tool shape specially designed for the first flange shape. A
third process might be to form thc second flange end shape using a similar process as the first process but using a tool specially designed for thc third flange shape. These shapes must be annealed using a similar. process as the first shape, either in separate steps or altogether.
100841 In embodiments, the internal diameter of the finished interatrial pressure vent is larger than about 5 mm to enable adequate venting of the left atrium and minimize damage to blood components from excessive shear stress, but enabling the interatrial pressure vent to stow in a placement catheter of smaller than about I4F.
[0085] In embodiments, the flow control element opening is at least about 50 sq.
mm.
100861 In embodiments, the flow control clement opening is 50 sq.mm. +- 10 sq.
mm.
[00871 In another embodiment, the cylindrical section is formed with an inside diameter of between 3 and 15 mm.
f 0088] The internal diameter of the body segment is preferably a constant dimension along the center, longitudinal axis of the interatrial pressure vent and is long enough to isolate the flow control element from deflection or damage as a result of contact with other structural elements of the heart.
100891 In embodiments, the body segment is formed into a substantially toroidal shape, the inner diameter tapering down and then up again from one side of the implant to the other.
[00901 In embodiments, the length of thc body section may be about 4 mm.

- 16 -100911 In embodiments, the length of the body section may be between about mm and about 40 mm.
[00921 In yct other embodiments, the flange segment may comprise at least a single loop which is oriented to the cylindrical shape by at least about 90' relative to the central axis of the cylinder and projected outward to a distance away from the center axis of greater than the opening in the atrial septum but at least about 3mm further than thc diameter of the inner cylinder.
[00931 In embodiments, the flange segment is formed of multiple struts that extend radially outward, with respect to the center aspect of the cylinder.
100941 In embodiments, the flange struts each comprise a substantially triangular shape that is wider adjacent to the body section than at the outer cdgc of the strut.
100951 In embodiments, the flange struts comprise a substantially triangular shape that is wider adjacent to the body section than at the outer edge of the strut and contains an integral hole at thc outer edge for containing a radiopaque marker.
100961 In embodiments, the flange struts comprise a substantially triangular shape that is wider adjaccnt to the body section than at thc outer edge of thc strut and whose outer edge is rounded to reduce trauma against the tissue it contacts.
100971 In embodiments, the flange struts are formed from a single beam of material that project outward from the center longitudinal axis of the body section.
100981 In embodiments, the flange segment is formcd of spiral shaped flange struts that arc coplanar and substantially orthogonal to thc central axis of thc cylinder.
100991 In embodiments, the flange segment is formed of at least one looping mcmbcr that attaches to at least one portion of thc body section.
[01001 In embodiments, the flange is preferably formed to automatically recover substantially to its preformed shape following partial deployment of the interatrial pressure vent from the placement catheter. In this manner, the interatrial pressure vent will resist being pulled back through the septa' opening.
101011 In embodiments, the flow control element device may be a tissue valve, a synthetic valve or a combination. The flow control element can be formed from animal or human tissue, such as bovine pericardial tissue. The procedures for obtaining these tissues and preparing thcm for use as implanted valve components are well known to those skilled in the art. The flow control element could be a trilcaflet valve, or also a bilcaflet valve, or also a simple flap valve. The flow control element

- 17 -could also be a ball and socket valve, a duckbill valve, a butterfly valve, or any other valve component known to those skilled in the art.
101021 In embodiments, thc flow control element can be biased by adding a separate component that is attached to at least one point along the body or flange segment and contacts against at least one point of the flow control clement surface at least at some point during its duty cycle. The component can bc preformed to controllably affect the flow control element behavior. For example, in one embodiment, the flange segment can be a looped wire formed from nitinol and connected to the body section and cantilevered against the surface of thc flow control element facing the left atrium and formcd so that the surface of the flow control element is biased to be slightly open when the pressure is equal in the left atrium and right atrium. Biasing can also be accomplished by varying the stiffness of thc material of the valve or components thereof.
101031 In embodiments, a flange segment could be formed out of a helical winding of nitinol, with a core wire to connect one end of the flange segment to the other end.
101041 In embodiments, the flow control element can be preshaped to resist moving against pressure in one direction.
101051 In embodiments, the flow control element could be biased to remain open at a predetermined pressure, or at a neutral pressure.
101061 In embodiments, the interatrial pressure vent consists of a body section and a flow control element; the body section comprising a cylindrical core segment and two flanged end sections; the flow control element being sealably secured to at least three points along the body section; thc flanged end sections each comprising at least one flange segment that extends radially outward from the body section;
the flow control clement comprising at least one movable clement that allows fluid passage in one direction with lower resistance than another direction.
101071 In embodiments, the body section is elliptical in shape, or cylindriod and designed to offset asymmetric stress created by a linear septa! opening.
101081 In embodiments, the formed metal flange segments consist of at least two flange segments, with at least one on each side of the septum.
101091 in embodiments, the flange segments arc positioned so they do not pinch the septum between them, thereby reducing possible pressure necrosis.

- 18 -WO 2010/129()89 10110] In embodiments, the flange segments arc shaped so the wall thickness perpendicular to the septum is less than the wall thickness parallel to thc septum, thereby increasing flexibility without decreasing strength.
101111 In embodiments, the flange segments are formed so the radius of curvature at the end is greater than about 0.03 inches.
101121 In embodiments, there is a radiopaque marker, preferably tantalum or platinum alloy, formed around, or integral with, the flange segment end to increase radiopacity and increase the area of contact between thc flange segment and septum.
[0113] In embodiments, the flange on the left atrium side of the septum is bent at a shorter radius of curvature than the right atrium side.
10114] In embodiments, the flange on one side of thc interatrial septum is formed to return to greater than a 90 angle relative to the axis of thc center cylinder.
101151 In embodiments, holes are preformed at a location along the cylindrical section for suture sites for securing the valving device.
101161 The above summary of the invention is not meant to be exhaustive.
Other variations and embodiments will become apparent from the description and/or accompanying figures disclosed herein and below. The embodiments described above employ elements of each other and are meant to be combined with each other.
For example, embodiments of flow control element may be used with differing configurations of thc body clement, flange, or segment thereof. While certain combinations arc disclosed, the invention is not so limited BRIEF DESCRIPTION OF DRAWINGS
101171 The present invention will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying figures. Understanding that these figures merely depict exemplary embodiments of thc present invention they arc, therefore, not to bc considered limiting of its scope. It will be readily appreciated that the components of the present invention, as generally described and illustrated in the figures herein, could be arranged and designed in a wide variety of different configurations.
Nonetheless, the invention will be described and explained with additional specificity and detail through the use of the accompanying figures in which:
Figure] is a schematic cross-sectional view of a patient's heart with an interatrial pressure vent of the present invention in situ;

- 19 -Figurc2 is an end view of the interatrial pressure vent of Figure 1 in situ as seen along line 2-2 of Figure 1;
Figure 2A is a end-on close up view of a flange segment of an embodiment of the present invention;
Figure 2B is an enlarged side cross-sectional view of an embodiment of the invention to illustrate variations in flexibility in a flange;
Figurc3 is a cross-sectional side view taken along line 3-3 of Figure 2;
Figure 4 is perspective view of thc body assembly of the interatrial pressure vent by itself;
Figure5 is a right side view of the body assembly of Figure 4;
Figure6 is a distal end view of the body assembly of Figure 4;
Figure7 is an enlarged fragmentary cross-sectional view taken along line 7-7 of Figure 6;
Figures 7A through 7C arc a side elevational views of embodiments of the device in the stowed position;
Figura is a side elevational view of the interatrial pressure vent of Figure 1 in a collapsed configuration prior to loading in a placement catheter;
Figure9 is a side view of the distal end of a placement catheter in its open position;
Figure 10 is a side view of the distal end of a placement catheter in its open position and with an interatrial pressure vent in its stowed configuration and in position over the inner shaft of the catheter;
Figure 1 1 is a side view of thc distal end of a placement catheter in a closed configuration with an interatrial pressure vent in its stowed configuration loaded onto the placement catheter;
Figure 11A is a side view of another embodiment of a placement catheter with an interatrial pressure vent stowed therein;
Figurel2 is an exploded perspective view of the proximal and distal ends of a placement catheter;
Figure 13 is a cutaway view of a heart of a patient and the distal end of a placement catheter in position across the interatrial septum;
Figure 14 is a schematic cross sectional side view of the proximal and distal end of a placement catheter in a closed position and positioned across the interatrial septum of the heart of a patient;

- 20 -WO 201()/129089 PCT/U
S201(1/(126574 Figurel5 is a view similar to Figure 14 but showing the distal cnd of the placement catheter in a partially open position and the distal flange segments of thc interatrial pressure vent deployed;
Figure16 is a view similar to Figure 15 but showing thc distal flange segments of the intcratrial pressure vent in position against the wall of the interatrial septum;
Figurel7 is an enlarged cross-sectional detail view of the distal end of the placement catheter of Figure 16 but showing the distal flange segments of the interatrial pressure vent being retracted from the interatrial septum as if it were determined to be in an undesirable position by imaging the radiopaque markers and going to be redeployed;
Figurel8 is a view similar to Figure 16 but showing further deployment of the interatrial pressure vent by releasing the proximal flange segments if imaging determines a correct positioning of the distal flange segments;
Figurel9 is an enlarged cross-sectional detail view of the placement;
catheter of Figure 18 but showing the intcratrial pressure vent fully released in position and the placement catheter being removed;
Figure 19A is schematic depiction of another embodiment of a placement catheter system and interatrial pressure device along with the deployment process therefor;
Figure 19B is schematic depiction of anothcr embodiment ()fa placement catheter system and deployment process therefor;
Figure20 is a side elevational view of an alternate embodiment of an interatrial pressure vent body with slanted flange segment ends;
Figure21 is a side elevational view of an alternate embodiment of an interatrial pressure vent body with staggered flange segment ends;
Figure 22 is a perspective view of an alternate embodiment of an interatrial pressure vent body with an integrated retrieval means and thrombus clot strainer;
Figure 23 is a right side view of the body assembly of Figure 22;
Figure 24 is an end view of an alternate embodiment of interatrial pressure vent;
Figure 25 is a cross-sectional side view taken along line 25-25 of Figure 24;

-21-Figure 26 shows and alternate embodiment wherein the core segment 106 is ovular rather than circular and thus the core segment is a cylindroid or elliptic cylinder rather than a simple cylinder;
Figure 27 is schematic depiction of another embodiment of a placement catheter system and interatrial pressure device along with the deployment process therefor;
Figure 27A is a side clevational view of the embodiment described in connection with Figure 27 in the stowed position;
Figures 28A through 28C depict other embodiments of the device that direct the flow of blood in a desired direction;
Figure 29 is an end-on view from the RA side of embodiments of exit profiles of the flow control element; and Figure 30 is a side view of an embodiment of the device having a tube-like extension into the RA side of the heart.
DETAILED DESCRIPTION OF INVENTION:
101181 Certain specific details are set forth in the following description and Figures to provide an understanding of various embodiments of the invention.
"Those of ordinary skill in the relevant art will understand that they can practice other embodiments of the invention without one or more of thc details described below.
Finally, while various processes are described with reference to steps and sequences in the following disclosure the steps and sequences of steps should not be taken as required to practice all embodiments of invention.
101191 As used herein, the terms "subject" and "patient" refer to any animal, such as a mammal like livestock, pets, and preferably a human. Specific examples of "subjects" and "patients" include, but are not limited, to individuals requiring medical assistance, and in particular, requiring treatment for symptoms of heart failure.
101201 As used herein, the term "pressure differential" means the difference in pressure between two points or selected spaces; for example between one side of a flow control element and another side of the flow control element.
101211 As used herein, the term "embolic particle" means any solid, semi¨solid, or undissolved material, that can be carried by the blood and cause disruption to blood flow when impacted in small blood vessels., including thrombi

- 22 -101221 As used herein, the terms "radially outward" and "radially away"
means any direction which is not parallel with the central axis. For example, considering a cylinder, a radial outward member could be a piece of wire or a loop of wirc that is attached or otherwise operatively coupled to the cylinder that is oriented at some angle greater than 0 relative to the center longitudinal axis of the cylinder.
101231 As used herein, the term "axial thickness" means the thickness along an axis parallel to the center longitudinal axis of a shape or component.
101241 As used herein, the term "axial direction" means direction parallel to the center longitudinal axis of a shape or component.
101251 As used herein, a "scalable connection" is an area where components and/or objects meet wherein thc connection defines provides for an insubstantial leakage of fluid or blood through the subject area.
101261 As used herein, thc term "lumen" means a canal, duct, generally tubular space or cavity in thc body of a subject, including veins, arteries, blood vessels, capillaries, intestines, and thc like.
101271 As used herein, thc tcrm "sealably secured" or "sealably connected"
means stably interfaced in a manner that is substantially resistant to movement and provides resistance to the flow of fluid through or around the interface.
101281 As used herein, the term "whole multiple" means the product contains no decimal.
101291 The present invention provides structures that enable several unique intracardiac and intraluminal valve devices and placement catheters therefor.
In some embodiments directed toward the intra-cardiac setting, these valve devices arc intended to allow sufficient flow from thc left atrium to the right atrium to relieve elevated left atrial pressure and resulting patient symptoms but also prevent the amount of flow from the right atrium to the left atrium to minimizc the potential for thrombi or other embolic material from entering the arterial circulation.
101301 However, it should be appreciated that the invention is applicable for use in other parts of the anatomy or for other indications. For instance, a device such as that described in this disclosure could be placed between the coronary sinus and the left atrium for the same indication. Also, a pressure vent such as is described in this disclosure could be placed between the azygous vein and the pulmonary vein for the same indication.

- 23 -Referring now to Figurel, one embodiment of invention is shown where the invention is used as an interatrial pressure vent. Figure 1 depicts the heart of a human subject. "LA" refers to the left atrium, and "RA" refers to the right atrium.
Thc interatrial septum is depicted as 107. Interatrial pressure vent 100 includes a body element 101 and flow control element 104, embodiments of which will be described in further detail below. The body element 101 comprises flanges 102 and 103. In this and other embodiments described herein, flanges 102 and 103 may be - annular flanges, which define a gap 2000 into which the septum 107 fits.
In embodiments, after insertion, the interatrial pressure vent is securely situated in an opening created in the intcratrial septum. Arrow F in Figurcl shows the direction of flow. It can be thus seen that a build up of pressure in the LA can be vented, by way of thc inventive device, to thc RA.

Referring now to Figure2, an embodiment of the interatrial pressure vent of the present invention is illustrated. Interatrial pressure vent 100 includes body element 101 comprising a substantially open mesh and including a substantially cylindrical core segment (shown end on) 106 and substantially annular flanges and 103. Flanges 102 and 103 may be comprised of any number of flange segments (or "flange elements" or "flange members") 102a-102h and 103a-103h, that are attached adjacent to the end of the core segment and extend radially outward from longitudinal axis of the core segment and flow control element 104. "Flange segments" may also be referred to as "legs" herein. The flanges 102 and 103 (and thus thc segments which comprise them 102a-h and 103a-h) in this and all embodiments disclosed herein, may also be integral with the core segment. That is, they need not be necessarily "attached" thereto but may be fabricated from the same material that defines the core segment (including in the manners described above and herein) and thus may be contiguous therewith. The flow control element may be attached to the body element, for example at locations 105. The flange segments in this and any embodiment of any annular flange may be formed of two individual strut elements or also can be formed of a single clement. The flange segments may be generally rectangular in cross section, circular in cross section, oval in cross section or some other geometric shape.
101331 In embodiments, the flange segments are designed to be more flexible than the core segment. In such embodiments, the increased flexibility may be achieved in several ways. In embodiments, a dimension of the surface of the strut elements that

- 24 -makc up the flange segments is altered relative to the corresponding dimension of the struts (or elements, or members) that make up the core segments. Figures 2A
illustrate such embodiments. Figure 2A shows an example flange segment 103a viewed end on. As shown, the end-facing dimension of strut element of 103x has a width D. By decreasing the width D in relation to the width of the outward-facing dimension of the struts that comprise the core segment, an increased flexibility of the flanges in relation to the core segment or othcr flange members (or portions thereof) can be achieved. Figure 2B shows an enlarged fragmentary cross-sectional of an embodiment of thc device substantially shown in Figure 6. Thc view is takcn along line 7-7 of Figure 6. In this figure, the cross hatched arca shows the area of increased flexibility. It can be seen that one area of thc flange segment is thus morc flexible than another arca. In embodiments where the strut elements are circular, then in a similar fashion, the diameter of the strut element could be made to have a diameters less than thc diameter of the strut (or similar elements) comprising the mesh-like configuration of the core segment. In embodiments where the flange element is made from a different section of material and is attached to the core segment, the segment material could be chosen to have a greater flexibility than the corc segment (or remaining portion of the flange segment or flange itself as the case may be).
The choice of materials based on their flexibility will be apparent to those skilled in the art. In the ways described above, the flange segments can achieve greater flexibility than the core segment (or the remaining portion of the flange segment or the flange itself as thc case may be) thereby reducing probability of damage to the tissue of the septum while allowing the core segment to maintain a strong outward force against the septal opening and thus decrease the probability that the device could become dislodged.
101341 In embodiments having an open-mesh configuration for the body element 101, the body element can be formed from a number of materials suitable for use in a patient, such as titanium, nitinol, stainless steel, Elgiloy, mp34n, Vitalium, Mobilium, Ticonium, Platinore, Stellite, tantalum, platinum, or other resilient material.
Alternatively, in such embodiments, the body element 101 can be formed from a polymer such as PTFE, UHMPE, HDPE, polypropylene, polysulfone, or other biocompatible plastic. Thc surface finish of the body element may be smooth with no edges or sharp discontinuities. In other embodiments, the surface finish is textured to induce tissue response and tissue in growth for improved stabilization. In

- 25 -embodiments, thc open mesh of body element 101 can be fabricated from a resorbable polymer such as polylactic acid, polyglycolic acid, polycaprolactonc, a combination of two or more of these or a variety of other resorbable polymers that are well known to those skilled in the art.
10135] In embodiments, the structure of the body element may be uniform and monolithic.
101361 In other embodiments, the body element (mesh or monolithic) comprises porous materials to encourage tissue ingrowth or to act as a reservoir for containing one or morc compounds that will be released over time after implant to address numerous issues associated with the product performance. These compounds can be used to diminish calcification, protein deposition, thrombus formation, or a combination of some or all of these conditions. The compound can also be used to stimulate an irritation response to induce tissue ingrowth. In embodiments, the compound can be an anti-inflammatory agent to discourage tissue proliferation adjacent to the device. Numerous agents arc available for all of such uses and arc familiar to those who arc skilled in the art.
10137] In embodiments, the material that comprises the body may be multilaycred comprising a coating of resorbable polymer or semipermeable polymer that may comprise various compounds that may be released, and in some embodiments in a controlled manner over time, after implant to address numerous issues associated with product performance.
10138] The mesh can be formed from wire that is pre-bent into the desired shape and then bonded together to connect the component elements either by welding them or adhesively bonding them. They could be welded using a resistance welding technique or an arc welding technique, preferably while in an inert gas environment and with cooling control to control the grain structure in and around thc weld site.
These joints can be conditioned after the welding procedure to reduce grain size using coining or upset forging to optimize fatigue performance.
10139J 1n other embodiments, the mesh can be formed from a hollow tube that has been slotted using, for example, a machining laser or water drill or other method and then expanded to form the open structure. If a sufficiently elastic and resilient material, such as nitinol, is used, the structure can be preformed into the finished shape and then elastically deformed and stowed during delivery so the shape will be elastically recovered after deployment. The surface of the finished assembly must be

- 26 -carefully prepared to insure is passivatcd and free of surface imperfections that could be nidus for thrombus formation.
[01401 In embodiments, the flow control clement 104 is a tissue valve such as a tricuspid valve, a bicuspid valve or a single flap valve formcd from pericardial tissue from a bovine, porcine, ovine or other animal. Any number of cusps may be used.
The flow control element is formed using a number of processing steps and auxiliary materials such as arc well known in the art.
10141J The flow control element 104 can also be a ball valve, a duckbill valve, a leaflet valve, a flap valve, a disc in cage type valve, a ball in cage type valve or other type of valve formed from a polymer or polymers or a combination of polymers, ceramics and metals such as dacron, teflon, polyurethane, PET or other suitable polymer; titanium, stainless steel, nitinol, MP35N, elgiloy, or other suitable metal;
zirconia, silicone nitride, or other suitable ceramic. Valves or portions thereof may comprise different stiffness/flexibly properties with respect to othcr valves or portions thereof in the flow control element.
101421 The flow control element 104 preferably extends to a point along the flange assembly 103 to enable creation of a sealable connection to the septum wall after placement. This is more particularly shown in Figure 3 where it can be seen that in embodiments, the flow control clement extends beyond the length of thc core segment and is folded and attachcd to the core segment so as to create a lip that extends in a dircction center of the opening in the vent. When the device is abutted against the septa' wall, this lip forms said sealable connection and thus can reduce the likelihood that blood can flow through the septal opening via pathways between the outer surface (septal-facing surface) of the interatrial pressure venting device and the septa! opening. The flow control clement 104 is attached to the body element 101.
This can be accomplished by using a suture material, such as silk, nylon, polypropylene, polyester, polybutylester or other materials such as arc well known to those skilled in the art. In embodiments, flow control clement 104 can be attached to body element 101 using adhesive bonding agents such as cyanoacrylate, polymethylmethacrylate, or other materials such as arc well known to those skilled in the art. In other embodiments, flow control element 104 can be attached to body element 101 via staples, rivets, rings, clamps or other similar methods as are well known to those skilled in the art.

- 27 -WO 2010/129()89 101431 As mentioned above, flow control clement can be made of material selected for its flexibility/stiffness. In embodiments where a loose valve is desired that resonates more closely with the cycle of the heart, a however stiffness material may be chosen. In embodiments where it is desired to open the valve when thc pressure differential reaches a selected value, the material of thc flow control element can be selected and/or processed in a manner to open at the desired differential. The leaflets or sections of the flow control clement itself may also comprise areas of variable stiffness, and or may be more flexible or less flexible than other leaflets or components of the flow control element.
01441 Figure 3 shows the device implanted in the atrial septum of the heart of a patient. As can be seen from thc figure, the core segment 106 can be formed contiguously with flanges 102 and 103 and thus flange segments 102a-102h and 103a-103h respectively. In the embodiment shown, flow control element 104 is contained within thc core segment 106 so it does not extend beyond thc face of thc body element 101, thereby insulating it from contact from other body structures or peripheral tissue. in embodiments, the core segment 106 can be extended to protrude beyond the interatrial septum 107 and thc flange assembly 102 and/or 103 on at least one side of the interatrial septum 107 and can be formed with a shape that extends to create a lip in the manner described above. In embodiments, thc ends of the flange assemblies 102, 103 arc formed to lie at a parallel angle to and against thc septal wall along at least a part of its length to increase the area of contact and thereby decrease the stress concentration against thc scptal wall.
101451 Referring now to Figure 4, an embodiment of the body clement of the present invention is shown. This perspective view of thc body clement 101 shows how, in embodiments, the ends of flange segments 102a-102h, 103a-103h arc rounded at their distal ends 115 and 116 to reduce stress concentrations against the interatrial septum after placement. This rounded shape can easily be formed as part of the integral shape of thc flange segment. In othcr embodiments , the thickness of the segment in this area may be decreased to decrease the stress further against the interatrial septum, which is similar to embodiments described above. Also similar to embodiments described above, if thc segment is round, the diameter can be decreased in order to increase flexibility. Also, as described above a different material of higher flexibility could be used for the end portions of the segments.

- 28 -[01461 While rounded shapes at the ends of thc flange segments reduce stress on the septum, other variations on this theme are contemplated. Figures 7A
through 7C
illustrate embodiments where the shape of thc end portions of the flange segments has configurations to achieve less stress against the septal wall ¨ among other goals.
Figure 7A is a side elevational view of embodiment of the pressure venting device in its stowed configuration. Core segment 106 of body element 101 is shown and, in this embodiment, is integral with flanges 103 and 102. The individual flange segments are not labeled; however, it is easily seen that flange 103 comprises segments substantial similar to those described above. There is no eyelet or opening at the end of the segment in the embodiment shown. Flange 102 shows an embodiment where the flange segment is not comprised of a triangular or multi-strut arrangement as described above but rather a single-member segment. Any flange of the present invention may be constructed with single-member segment. An example single member is referred to as 103s. In this example, at the end of each single-member flange segment (102s) for example, there is an eyelet. Figure 7B shows an embodiment similar to that shown in Figure 7A where the end of the segments 102s are not eyelets but rather pads. Figure 7C shows another embodiment where the ends of the segments 102 arc paddle shaped. Other smooth-edged shapes could be used, and it should be understood that such shapes and configurations apply to all manner of flange segment ends, not only single-member segments. This would include the ends of flange segments shown and described herein, for example with reference to Figures 2 through 7.
[01471 Figures 7A-C also show embodiments having at least one flange segment being longer than the other flange segments. Again, while represented as single-member flange segments they need not be and as such a configuration with at least one longer segment may apply to any flange-segment configuration disclosed herein.
Thc benefits and purpose of having at least one longer flange segment will be described more fully below.
101481 ln embodiments, the outer ends of thc flange segments 102a-102h, 103a-103h arc formed with integral marker holes or slots 109 and 110 (shown in Figs 3 and 7 for example) in which markers 118 and 119 can be positioned so the device may morc easily be visualized using radiographic imaging equipment such as with x-ray, magnetic resonance, ultrasound or other imaging techniques. Markers as disclosed herein may be applied to the ends of any segments, not just those with holes or eyelets

- 29 -WO 2010/129()89 therein. A radiopaque marker 118 and 119 can be swaged, riveted, or otherwise placed and secured in the hole and thereby dimensioned to be flush with the end of the segment. Markers may also be simply attached or to end of a segment not having a hole. in all embodiments having markers, flange ends 115 and 116 arc more visible when imaged. In other embodiments, the markers 118 and 119 can be bonded with an adhesive agent such as cyanoacrylatc or epoxy or a variety of other materials that are available and suitable for implant as are well known. The markers may be proud (as shown for example in Figure 7) or flush with the end of the flange segment.
The radiopaqu.c marker 118 and 119 may be formed of tantalum, tungsten, platinum irridium, gold, alloys of these materials or other materials that are known to those skilled in the art. Also markers 118 and 119 comprising cobalt, fluorine or numerous other paramagnetic materials or other MR visible materials that arc known to those skilled in the arts can be incorporated together with the radiopaque materials, or in alternating locations of the flange segments to enable both x-ray and MR
imaging of the interatrial pressure vent. Alternatively, the ends of the flange elements 102a-102h and 103a-103h can be wrapped with a foil made of the same marker materials. In embodiments, thc radiopaque material can be laminated to thc flange segments and bonded through a welding process or using an adhesive such as cyanoacrylate or numerous other adhesives known to those skilled in the art.
10149] Suture rings 117 can be formed in the body element to locate and fix the attachment site along the body element to the flow control element. The suture rings can be circular holes formed into thc structure or they could also be some other shape such as rectangular or triangular and also can be formed as a secondary step, for example by standard machining techniques, using a secondary laser machining step, or with electro-chemical etching. Preferably the connection between a segment and any other segment of the body element arc formed with as large a radius as possible to increase resistance to fatigue failure. Also, preferably, all edges of the formed device are rounded to improve biocompatibility and hemocompatibility.
101501 The pattcrn of suture rings as well as which of the rings are selected during suturing may affect the properties of the flow control element. For example, in embodiments where it is desired to have the flow element loose and flappable, less suture rings may be utilized and, in such embodiments, RA-side end of the flow control element may contain relatively less sutures than the LA side. In other embodimentsõ it may be desirable to keep the flow control element affixed to the

-30-core segment for a increased length of the segment thereby reducing the amount of flow control element material that affecting flow. Still in other embodiments the top or bottom portion the flow element at the RA side may be sutured in such a way so as to allow the top or bottom portion of the flow control element to affect flow more than the other portion respectively. Embodiments discussed below where the flow is "aimed"
may utilize suturing patterns effective to enable the desired flow control element configuration.
[0151] Retuning to the flange segments, in an embodiment, the interatrial pressure vent 100 is comprised of an equal number of flange segments on each side of the interatrial septum. In embodiments, there are eight flange segments on each side of the core segment.
In another aspect there are an equal number of suture rings and flange segments on one side of the interatrial pressure vent. In other embodiments, there are seven flange segments on each side of the core segment. In other embodiments, there are six flange segments on each side of the core segment. In other embodiments, there are five flange segments on each side of the core segment. In other embodiments there are four flange segments on each side of the core segment. In other embodiments there are three flanges on each side of the core segment. In other embodiments there are two flanges on each side of the core segment. In other embodiments, there is one flange on each side of the core segment. Still in other embodiments there are more flange segments as compared to flange segments. And in other embodiments, there are more flange segments as compared to flange segments. As can be seen there are a number of variations for the number of flange segments and the scope of the claims should not be limited by these particular embodiments, but should be construed in a manner consistent with the specification as a whole.
[0152] Referring now to Figure 5, the body element of an embodiment of the present invention is displayed in side view. The flange segments can be formed to produce a gap G (also referred to as an annular gap) between the ends of flange segments on one side of the body and flange segments on the other side of the body, when the device is in its "native" or un-deployed state. When the device is deployed, it flexes to accommodate the tissue and as such the gap may expand when tissue is positioned therein. In embodiments, this gap is slightly smaller than the thickness of the interatrial septum. In other embodiments, the gap can be larger than the thickness of the interatrial septum. In other embodiments the gap can be zero. In another aspect the gap can be negative: in this case the flange segments on each side of the

-31-body can be formed to cross each other in order to exert more pressure between the deployed flange segments and the interatrial septum. Also shown in Figure 5 are radiopaque markers 118 and 119, which in embodiments arc shown to be located adjacent to the end of the flange segments.
101531 Referring now to the embodiment shown in Figure 6, the flange segments 102a-102h are oriented so they arc not directly opposed to flange segments 103a-103h on the opposite side of the body element so that after placement there is no pinching points thereby reducing the chance for tissue injury. In embodiments, flange segments 102a-102h are arranged midway between adjacent ends of flange segments 103a-103h. In embodiments the length of flange segments 102a-102h arc similar to the length of flange segments 103a ¨ 103h. However in othcr embodiments the length of flange segments 102a-102h are identical to thc length of flange segments 103a ¨
103h; the length of flange segments 102a-10211 arc longer than 103a-I03h; and thc length of flange segments 102a-102h are shorter than flange segments 103a-103h.
101541 Referring now to Figure 7, in embodiments having radiopaque markers it can be seen that thc radiopaque markers 118 and 119 may be placed into the marker holes 109 and 110 (or placed on the ends of flange segments that do not have holes) to locate the ends of the flange segments 102a-102h and 103a-103h with a non-invasive imaging technique such as with x-ray or MR1 during or aftcr the procedure. In embodiments, the markers 118 and 119 can be formed to be flush in an axial direction with the outer surface and thc inner surface of the flange segments 102a-102h and 103a-103h. In another aspect, the markers 118 and 119 can be formed to extend in an axial direction beyond the outer surface of the flange segments 102a-102h and 103a-103h, away from the interatrial septum. In embodiments, the markers 118 and can be formed to extend in an axial direction beyond the inside of the flange segments 102a-102h and 103a-103h, toward the interatrial septum. In embodiments, thc markers 118 and 119 can be formed to extend in an axial direction beyond the inside and the outside of the flange segments 102a-102h and 103a-103h. In embodiments, the markers 118 and 119 can be formed to be recessed in an axial direction within the surface of the inside of the flange segments 102a-102h and 103a-103h. In embodiments, the markers I 18 and 119 can be formed to be recessed in an axial direction within thc outside of the flange segments 102a-102h and 103a-103h.
In embodiments, the markers 118 and 119 can be formed to be recessed in an axial direction within both the inside and the outside of the flange segments 102a-102h and

- 32 -WO 2()10/129089 PCT/US2010/02657:1 103a-103h. In embodiments, the markers 118 and 119 can bc formed to extend in a radial direction within the width of the flange segments 102a-102h and 103a-103h. In embodiments, the markers 118 and 119 can be formed to extend in a radial direction flush with the width of the flange segments 102a-102h and 103a-103h.
[01551 Referring now to Figure 8, an interatrial pressure vent 100 of thc present invention is shown in its stowed configuration. In embodiments, the interatrial pressure vent can be collapsed to a substantially cylindrical shape for stowing in a delivery catheter during placement. Flange segments 102a-IO2h and 103a-103h can be fabricated to be substantially equal in length. Thc "stowed position" is not meant to apply only to devices having flange segments of equal length but rather to all embodiments of the venting device disclosed herein. Devices having flange segments of varying length and orientation such as those described herein arc also designed to stow in substantially the same manncr as shown in Figure 8. In an embodiment seen in Figure 20, flange segments 202a-202h and 203a-203h are formed on a slanted angle so that, when marker elements are secured to the ends of thc flange segments, the flange segments can be stowed into a smaller volume. In embodiments 300 seen in Figure 21, flange segments 302a-302h are formed of alternating length to allow stowage into a smaller volume.
(01561 Referring now to Figure 9, an embodiment of thc distal end of the placement catheter 111 of thc present invention is shown in its open position.
The inner shaft 112 is fabricated with a center lumen 136 of sufficient diametcr to contain a guidcwirc 138 or also for use in injecting contrast or other liquid.
Commonly, thc lumen would be sized for a guidewire of 0.010", 0.011", 0.014", 0.018", 0.021", 0.028", 0.035", 0.038", 0.042" or 0.045". This lumen 136 can also be used to measure pressure at the distal end of the catheter using other equipment and techniques that are well known to those skilled in the art. The lumen 136 preferably extends through the entire length of the inner shaft 112. Alternatively, the guidewire lumen 136 can extend for a shorter length in the proximal direction and then through a side holc (not shown) of the inner sheath. A corresponding side hole (not shown) is placed on the outer shaft 113 adjacent to the side hole in the inner shaft 112 to create a pathway between the center lumen 136 of the inner shaft 112 and the outside of thc outer shaft 113. In this way it is possible to pass a guidcwire from this distal end of the inncr lumen 136 through the side hole and exchange the catheter over a guidewire

- 33 -that is less then twice the length of the catheter 111 while securing the guidcwirc position during exchange.
101571 In embodiments, the inncr shaft 112 is configured with a waist section 120 to contain the folded interatrial pressure vent 100 between thc gap formed in the space outside of this section of inner shaft 112 and the inside of the outer shaft 113. The inner shaft 112 is may bc formed to contain at least onc circumferential groove 114 at the proximal end of waist section 120 that forms a recess between thc inside of the outer shaft 113 and the smallest diameter of the groove that is greater than the gap formed in the space between the waist section 120 and the inside of the outer shaft 113. Radiopaque markers 118 can extend in a radial direction past the outer surface of the flange segments 102a-102h and in embodiments, when interatrial pressure vents of the present invention are is folded into thcir stowed configuration and placed into position over inner shaft 112, radiopaque markers 118 are dimensioned to fit into groove 114. Other similarly dimensioned sections may be used; that is, that which fits into the groove need not necessarily be a radiopaque marker. In embodiments, whcn interatrial pressure vents of the present invention are stowed in this manncr, the gap between waist section 120 and the inside of outer shaft 113 is not sufficient to allow radiopaque markers 118 beyond thc distal end of groove 114 unless the outer sheath 113 is retracted beyond the proximal end of groove 114.
101581 The inner shaft 112 may be formed with a groove 121 on the distal end of the waist section 120 adjacent to thc location of the distal end of the interatrial pressure vents of the present invention are radiopaque markers 119 (or similar dimensioned members) can extend in a radial direction past the outer surface of the flange segments 102a-102h and in embodiments, when interatrial pressure vents of the present invention are folded into its stowed configuration and placed into position over inner shaft 112, radiopaque markers 119 are dimensioned to fit into groove 121.
In another aspect, the inner shaft 112 may be formed with a circumferential groove 114 on thc proximal end of waist section 120 and a circumferential groove 121 on the distal end of the waist section 120 The inner shaft can be formed of a variety of polymers or metals or combinations of polymers and metals that are suitable for use in a patient. The inner shaft can be fabricated from a single length of PTFE, UHMWPE, FEP, HDPE, LDPE, polypropylene, acctal, Delrin, nylon, Pebax, other thermoplastic rubber, aliphatic or aromatic polyurethane, or a variety of other engineering resins that arc well known to those skilled in the art. In embodiments, the

- 34 -inner shaft can be fabricated using multiple layers of two or three of the above-mentioned polymers to combine desirable properties of each. For example, the outer surface could be composed of polyurethane to enable easier bonding of auxiliary components to the inner shaft. The inner layer could be PTFE to convey better lubricity to the inncr shaft. In embodiments, the inner shaft and or the outer shaft could be coated on the inner and or outer surface with a coating material that conveys specific properties to the shaft like antithrombogcnicity or lubricity. There arc numerous available coating materials suitable for these purposes as are well known to those skilled in the art. The inner shaft can be compounded with a radiopacifier to increase the visibility of thc inner shaft under fluoroscopy using bismuth salts such as bismuth subcarbonate, bismuth oxychloride, bismuth trioxide, tungsten powder, molybdenum powder or other radiopacifier such as arc well known to those skilled in the arts. Similarly, the outer sheath can be fabricated from the same set of materials as the inner sheath, in the same manner and using the same coatings.
Embodiments described below in connection with a flange rather than circumferential groove operate in substantially the same manner as described above and hcrcin, except the device does not necessarily have projections that fit into and are retained by the grooves.
101591 Referring now to Figure 10, a folded representative intcratrial pressure vent 100 of thc present invention is shown in its stowed position with the placement catheter 111 of the present invention shown in its open position. In practice, if the body of the intcratrial pressure vent is fabricated of nitinol or other elastic material, when the placement catheter is in its fully open position, thc flange segments 102a-102h and 103a-103h would automatically recover into a shape like that shown in, for example, Figure 4, hence this Figure is shown to illustrate the position of the intcratrial pressure vent 100 relative to the waist section 120 and grooves 114 and 121. When radiopaque markers (or similarly dimensioned members) 118 extend beyond the thickness of the inside of body segment 101 of intcratrial pressure vent 100, they form a projection within intcratrial pressure vent 100 that can be captured within groove 114 to secure the position of the intcratrial pressure vent 100 during placement. During deployment, the outer shaft 113 of placement catheter 111 is retracted a sufficient distance to reveal the distal portion of the intcratrial pressure vent 100 allowing the flange segments 103a-103h to dilate radially away from the central longitudinal axis of body 101. By capturing the radiopaque 118 markers

-35-within the groove 114, the device can be repositioned easily without further deployment, or the device can be completely retracted and removed from the patient without deployment as indicatcd in Figure 17.
101601 Referring now to Figure 11, an interatrial pressure vent 100 of the present invention is shown completely stowed within thc placement catheter 111 of the present invention.
101611 Figure 11A shows an embodiment of the placement catheter similar in operation to those described herein but operative to engage an interatrial pressure vent by way of a slightly different mechanism than described above in connection with circumferential grooves. This figure shows a schematic depiction of a stowed interatrial vent. Rather than having the grooves as described above, this embodiment of a placement catheter comprises an inner shaft having a flange or member (rather than a groove) which has a diameter larger than that of the inner shaft to grip and hold an end of thc interatrial vent device as shown. As shown in the figure, the flange and its segments (collectively referred to in thc figure as 102) wrap around thc ball-shaped flange 3000 and allow the interatrial pressure vent to be moved with the placement device in the manners described herein.
101621 Referring now to Figure 12, a placement catheter 111 of the currcnt invention is shown. It should be noted that while the inner shaft is depicted as having grooves in Figure 12, thc inner shaft may comprise the flange 3000 as described above in connection with Figure 11A. The skilled artisan will appreciate that the operation of the device is substantially similar whether grooves or flanges arc utilized.
The placement catheter 111 comprises a first handle component 128 that can be attached to outcr shaft 113. The first handle component can be attached to the outer shaft 113 using a variety of adhesive methods such as solvent bonding using a solvent for both the handle and outer shaft material; an organosol consisting of a solvent and polymer in solution that is compatible with both the outer shaft and the first handle component; a polymerizablc adhesive, such as polyurethane, cyanocrylate, epoxy or a variety of other adhesives as are well known to those skilled in the art. The first handle component can be fabricated from a variety of metals such as aluminum, stainless steel, titanium or a number of other metals and alloys as arc well known to those skilled in the art. In embodiments, the first handle component 128 is fabricated from a polymer such as polycarbonate, or a variety of engineering resins, such as Lexan, or others as arc well known to those skilled in the art. The first handle

- 36 -component comprises hand grip section 124 and tubular shaft section 125. The tubular shaft section 125 can contain kcyway 122 that is formed or machined into the shaft section. The keyway is preferably formed with three linear sections; a first linear section 131, a second linear section 132 and a third linear section 133. Each of these sections is formed to traverse along a path primarily parallel with the center axis along the length of the first handle component but each is displaced radially from one another by at least about half of thc width of the kcyway. The placement catheter 111 also can comprise a second handle component 129 that can be attached to inner sheath 112. The second handle component can be fabricated from the same variety of metals and polymers as the first handle component. The two handles can be fabricated from the same materials or from different materials. Thc second handle component can be attached to the inner sheath in the same manner and using the same materials as the first handle component attaches to the outer sheath. In embodiments, the second handle component can contain threaded hole126 for containing set screw 127.
The sct screw can be twisted to capture the inner shaft against the second handle component. The second handle component 129 also can comprise a second hand grip section 134 and second tubular shaft section 130. The second tubular shaft section can contain key 123 that is formed or machined of suitable dimension to adapt to keyway 122 of first handle component 128. When assembled, second handle component 129 can be slideably moved relative to first handle component 128 in a manner controlled by the shape and length of the key way 122. As the second handle 129 is advanced relative to thc first handle 128, it can be appreciated that he inner sheath 112 will slide in a distal dircction out from the outer sheath 113. It can be appreciated that whcn the second handle component 129 is assembled, the key 123 is slid into the first linear section 131 and advanced until it hits the edge of thc keyway formed between the first linear section 131 and the second linear section 132.
In order for the second handle component 129 to advance further, it must be rotated and, once rotated, it can be advanced further but will stop when the key 123 hits thc edge of the keyway formed between the second linear section 132 and the third linear section 133. The keyway dimensions arc preferably selected with consideration for the combination of lengths of other components in the placement device. A
first position, defined as the position when the key 123 is in contact with the proximal edge formed between the first linear section 131 and the second linear section 132, is preferably determined so, when fully assembled and with the interatrial vent in its

-37-WO 2()10/129089 stowed position within the placement catheter, the outer shaft 113 will completely cover the length of the interatrial pressure vent 100 as is desired during catheter placement. The keyway dimensions can also be selected to result in a second position, defined as thc position when the key 123 is in contact with the distal edge formed between thc second linear section 132 and third linear section 133. The second position would preferably be selected to reveal the full length of flange segments 103a-103h but retain flange segments 102a-102h within the outer shaft of the catheter. The length of the third linear section 133 would preferably be selected so that, when the second handle component 129 was advanced completely against the first handle component 128, the full length of thc interatrial vent 100 would be uncovered by the outer shaft 113 and the device would be deployed. A variety of other configurations of the first and second handle components could be used for this same purpose. The first handle component tubular shaft section 125 and the second handle component tubular shaft section 130 could be threaded (not shown) so the first handle component 128 could be screwed into the second handle component 129.
Alternatively, gear teeth (not shown) could be formed in the first tubular shaft section 125 of the first handle component 128 and a gear wheel (not shown) could be incorporated into the second shaft tubular section 130 of the second handle component 129. The gear wheel would preferably be chosen to mesh with the gear teeth and the second handle component 129 could be advanced toward the first handle component 128 by rotating the gear wheel. A variety of other design configurations could be utilized to control the relative location between the first handle component and thc second handle component as are well known to those skilled in the art.
101631 Figures 13 through 17 show embodiments of a system for treating heart failure of the present invention. More specifically Figures 12 through 19 show how the placement catheter is introduced and positioned in a patient and methods for placing the interatrial valve in a patient. The interatrial pressure vent 100 is presterilized and packaged separately from the placement catheter 111.
Sterilization can be performed by exposing the device to a sterilizing gas, such as ethylene oxide, by exposing the device to elevated temperature for an adequate period of time, by using ionizing radiation, such as gamma rays or electron beam or by immersing the device in a fluid that chemically crosslinks organic molecules, such as formaldehyde or gluteraldehyde and then rinsed in sterile water or sterile saline. For each of these sterilization methods, consideration must be given to compatibility of thc materials so

-38 -device performance is not adversely affected as a result of the sterilization process.
Also, the packaging design and materials must be carefully considered with the sterilization procedure, post sterilization handling and storage, environmental exposure during storage and shipment, and ease of handling, opening, presentation and use during the procedure.
101641 In embodiments, interatrial pressure vent 100 can be assembled using components that have been pre-sterilized using one of the above methods or others that are well known and the final assembly may be accomplished in an aseptic manner to avoid contamination.
101651 In embodiments, the intcratrial pressure vent 100 can be supplied non-sterile and be sterilized around the time of use using onc of the above methods or by other methods well known by those skilled in the art.
101661 Similarly, the placement catheter 111 may be pre-sterilized and packaged separately from the interatrial pressure vent 100. Sterilization can be performed using a similar method to the interatrial pressure vent 100 or using a different method from the same choices or using some other method as is well known by those skilled in the art.
101671 In embodiments, an interatrial pressure vent 100 and the placement catheter 111 can be supplied pre-sterile and in the same package. In another aspect, the interatrial pressure vent 100 and thc placement catheter 111 can be preloaded and supplied pre-sterile.
101681 Prior to insertion, the interatrial pressure vent 100 is preferably folded and stowed onto the placement catheter 111. This can be accomplished in a sterile field and using aseptic techniques in the following steps. First the interatrial pressure vent 100 is presented to the sterile field and the placement catheter 111 is presented to the sterile field. Second, the interatrial pressure vent 100 and placement catheter 111 arc inspected for visible signs of damage, deterioration or contamination. Third, the second handle component 129 of thc placement catheter 111 is retracted fully so the outer shaft 113 exposes the inner shaft 112 to the maximum extent allowed.
Fourth, the interatrial pressure vent 100 is positioned in the correct orientation over the inner shaft 113 of the placement catheter 111 with the inncr shaft 113 oriented through the center of the flow control element 104. Fifth, the flange segments 102 a-h and 103 a-h arc folded away from each other and thc flange segments 102 a-h and 103 a-h and the core segment 106 are compressed radially to fold the interatrial pressure vent 100

- 39 -into a size and shape that will fit over and onto the waist section 120 of the inner shaft 112 with the distal ends 115 of flange segments 102a-h aligning with the proximal groove 114 of inner shaft 112. In embodiments comprising a flange as described in Figure 11A the flange segments 102 a-h and 103 a-h are folded away from each other and the flange segments 102 a-h and 103 a-h and the core segment 106 are compressed radially to fold thc intcratrial pressure vent 100 into a size and shape that will fit over the flange 3000 described on Figure 11A . This folding may be accomplished with the aid of an insertion tool (not shown) that retains the intcratrial pressure vent 100 in a stowed position on inncr shaft 112 and then advancing outer shaft 113 over the stowed interatrial pressure vent 100 and displacing the insertion tool, thereby leaving the outer shaft I 13 completely covering the interatrial pressure vent 100 and mating with the distal tapered tip 140 of the inner shaft 112. In other embodiments, this can be accomplished by hand using the fingers of one hand to hold the distal ends 115 of the flange segments 102a ¨ 102h in position at groove 114 of thc inner shaft 112 and advancing the outcr shaft 113 over the inncr shaft 112 enough to.hold the flange segments 102a-102h in place. Completion of the loading procedure is accomplished by progressively advancing the outcr shaft 113 until it completely covers the interatrial pressure vent 100 as shown in Figurcs11 and 11A. While the below discussion regarding placement of the interatrial pressure vent uses the placement device shown in Figures 9-11 as an example, the description on placement and thc procedure therefore is also meant to apply to embodiments where the inner shaft comprises a flange rather than grooves.
10169] Positioning of thc loaded interatrial valve 100 and placement catheter 111 in preparation for implanting the interatrial valve 100 in the patient can be accomplished by: first gaining vascular access; second, positioning a guidcwirc 121 in thc right atrium of thc patient; third, positioning an introducer (not shown) into thc patients right atrium; fourth, locating the interatrial septum; fifth, advancing the introducer through the interatrial septum and into the patient's left atrium;
sixth, advancing the guidewire 138 into the left atrium; seventh, retracting the introducer;
eighth, advancing the loaded placement catheter 111 and interatrial pressure vent 100 into position so thc distal end and approximately half of th.e stowed length of the interatrial pressure vent 100 is protruding through the interatrial septum and into the patient's left atrium as shown in Figure13.

-40-WO 201(1/129089 101701 In embodiments, positioning of the loaded interatrial valve 100 and placement catheter 111 in preparation for implanting the interatrial valve 100 in the patient can be accomplished by: first gaining vascular access; second, positioning a guidewire 138 in the right atrium of the patient; third, advancing the loaded intcratrial valve 100 and placement catheter 111 over guidewire138 by inserting the guidcwire into and through lumen 136 and advancing placement catheter 111 into the patient's right atrium; fourth, locating the interatrial septum; fifth, advancing the placement catheter I 11 through the interatrial septum and into the patient's left atrium so the distal end and approximately half of the stowed length of the interatrial pressure vent 100 is protruding through the interatrial septum and into the patient's left atrium as shown in Figure13.
101711 Implanting interatrial pressure vent 100 into a patient can be accomplished, once the loaded interatrial pressure vent 100 and placement catheter 111 arc in position as shown in Figure14, by first, retracting first handle component 128 toward second handle component 129 while holding second handle component 129 until flange segments 103a-h arc fully uncovered as shown in Figure15, and as can be verified by visualizing thc markers 119 using fluoroscopy or MRI or using echocardiography; second, retracting the placement catheter 111 with partially deployed interatrial pressure vent 100 toward the patient's right atrium until the flange segments 103a- h are in contact with the left atrial side of thc interatrial septum, as shown in FigurcI6, and as can be verified using the same techniques mentioned or as can be perceived by the user based on the resistance felt against further proximal movement of thc placement catheter 111; fourth, continuing to retract the outer sheath 113 by retracting second handle 129 until the outer sheath 113 is retracted beyond the proximal end of groove 114 of inncr shaft 112 and also uncovers flange segments 102a- h, at which time the flange segments 102a -h of interatrial pressure vent 100 will deploy returning to the preloaded geometry and capture the interatrial septum between the flange segments 103a-h and flange segments 102a-h as shown in shown in Figurel8; fifth, thc inner sheath is retracted through the flow control clement 104 of interatrial pressure vent 100, into the patients right atrium as shown in Figurel9; fifth the second handle component 129 is advanced toward the first handle component 128 to reposition inner shaft 112 into the position relative to outer shaft 113 it was in during placement and the placement catheter is removed from the patient and the procedure is completed.

-41 -101721 In other embodiments, implanting intcratrial pressure vent 100 into a patient can be accomplished, once the loaded interatrial pressure vent 100 and placement catheter 111 are in position as shown in Figure14, by first, advancing second handle component 129 toward first handle component 130 whilc holding first handle component 128 until flange segments 103a-h arc fully uncovered as shown in FigureI5, and as can be verified by visualizing the markers 119 using fluoroscopy or MRI or using echocardiography; second, retracting thc placement catheter 111 with partially deployed interatrial pressure vent 100 toward the patient's right atrium until thc flange segments 103a- h arc in contact with the left atrial side of the interatrial septum, as shown in Figure16, and as can be verified using the same techniques mentioned or as can be perceived by thc user based on the resistance felt against further proximal movement of the placement catheter 11 1; fourth, continuing to retract the outer sheath 113 by retracting second handle 129 until the outer-sheath 113 is retracted beyond the proximal end of groove 114 of inner shaft 112 and also uncovers flange segments 102a- h, at which time the flange segments 102a -h of interatrial pressure vent 100 will deploy returning to the preloaded geometry and capture the interatrial septum between the flange segments 103a-h and flange segments 102a-h as shown in shown in Figurel8; fifth, the inner sheath is retracted through the flow control element 104 of interatrial pressure vent 100, into the patients right atrium as shown in Figurel9; fifth the second handle component 129 is advanced toward the first handle component 128 to reposition inner shaft 112 into the position relative to outer shaft 113 it was in during placement and the placement catheter is removed from the patient and the procedure is completed.
101731 For a variety of reasons, it may be necessary or desirable to remove interatrial pressure vent 100 and placement catheter III during any part of the procedure without further risk or injury to the patient. This is possible as follows: if, for any reason, it is desired for the device to be removed before outer shaft 113 is retracted and flange segments 103a-h are deployed, then the placement catheter III
with interatrial valve 100 can simply be retracted out through the same pathway as introduced.
[01741 If, following deployment of flange segments 103a-h it is necessary or desirable to remove the device, then thc intcratrial valve 100 can be retracted into the placement catheter 111 by advancing first handle 128 away from second handle 129, while holding second handle 129 stationary, thereby advancing outer sheath 113

- 42 -WO 2()10/129089 distally through thc interatrial septum and over the flange segments 103a-h.
In embodiments, radiopaque markers 118 placed in marker holes 109 are captured in groove 114 (see Figure17) and cannot fit in the gap between waist 120 of inner shaft 112 and inner surface of outer shaft 113, so as outer sheath 113 is advanced, flange segments 103a-h are forced to fold inward toward thcir stowed position and arc retracted back onto inner shaft 112 and within outer sheath 113. Once outer shaft 113 is fully advanced, catheter 111 can be retracted as shown in Figurc17 to be removed out through the interatrial septum and out through the same pathway as introduced.
[01751 Figure 19A is embodiment of thc invention designed to enhance the retrievability of the device. The procedure for implanting the device is substantially similar to that which is described above; however, thcrc are variations to the placement catheter and the device, which will be described below. As discussed in connection with Figures 7A through 7C, embodiments of the interatrial venting device comprise at least onc flange segment being longer than the other flange segments. The embodiment schematically shown in Figure 19A preferably works with such embodiments having at least onc flange segment that arc longer in relation to the other flange segments; thus the segments shown in the RA have the same reference number as the longer segments in Figures 7A through 7C, i.e., 102L.
In embodiments utilizing the techniq-ues shown in Figure 19A, the opening 113a of outer sheath 113 of placement catheter is angled or has a more surface area on one side relative to the other. The placement catheter is oriented during the procedure such that the angled opening (or thc plane of the opening itself) is at an angle more normal to the septa! wall 107. In the embodiment shown in Figure 19A, that angle appears to be around 45 degrees with respect to the septa! wall 107, but any angle which provides an more normal angle with respect to the septal wall may be used, and any opening which provides more surface area of thc outer sheath 113 on one side with respect to the other side may be used. Reference numerals 4000 through 4050 refer to steps in thc process described below. The process is largely similar to that described above or with respect to any well-known placement catheter system and process, therefore only the applicable differences will be described. As can bc seen at steps 4000 through 4020, the placement catheter is positioned and the device is in the beginning stages of deployment. At steps 4030 and 4040, the as the outer sheath 113 is retracted and on the RA side (or when the inner shaft is advanced while the outer sheath is on the RA side, which is not shown), the opening allows one of the longer

-43-flange segments 102L to be deployed after other flange segments have been deployed and are thus in contact with the septum 107. The at least one longer flange segment 102L is retained in the placement catheter system by way of the outer sheath 113, the length of which extends further on one side than the other due to the opening and thus covers the longer segment 102L while thc other shorter segments have been deployed.
In this way, the operator of the placement catheter can determine if thc interatrial device is in the proper position. If not, the operator can still retrieve the device up until the last point prior to full deployment, i.e., when at least one of the longer flange segments (102L for example) is still retained in the placement catheter by thc outer sheath 113. If it is in proper position, the deployment may commence.
[0176J Another deployment embodiment is now described in connection with Figure 19B. This deployment embodiment may be used with any embodiment of thc intcratrial vent described herein. Reference numerals 5000 through 5050 refer to steps in the process described below. At step 5000, the LA side of the device (generally referred to in this figure as 100) is deployed on the LA side of the heart.
Further deployment is shown at step 5010 and the outer sheath is retracted into the RA
side of thc heart, which allows flow control element 104 to exit the placement catheter.
Placement catheter is equipped with a balloon, which is in fluid communication, for example, with lumen 136 described above or guide wire 138. The skilled artisan will appreciate other configurations in which a balloon catheter may be provided in the placement catheter system. Upon deployment of the LA side flange or shortly thereafter, 'balloon 139 is inflated (shown in step 5020). The inflation of the balloon optionally coupled with a pulling-back motion of the placement catheter 111 holds thc device 100 against the LA side of the septa' wall 107 and thereby prevents thc device 100 from dislodging during deployment and/or moving in a direction away from the septa! wall. Step 5040 shows the full deployment of thc device 100 while the balloon 139 is inflated. When satisfactory deployment is achieved, thc balloon 139 is deflated and the placement catheter system is removed (shown at step 5050).
101771 Now referring to Figure20, an interatrial pressure vent 200 of the present invention is shown. In embodiments, flange segments 202a-h and 203 a-h can be formed with graduating length to reduce interference between flange segments 202a-h and 203a-h during handling, folding and loading. In embodiments, radiopaque markers 218 and 219 protrude into the inner cylindrical shape of the stowed position of thc interatrial pressure vent and each flange segment 202a-h and 203a-h differ in

- 44 -length by at least the width of the radiopaque markers 218 and 219. In embodiments, each flange segment 202a-h and 203a-h diffcr in length by at least at least 1 mm. In embodiments, each flange segment 202a-h and 203a-h differ in length by at least 2%
of thc overall length of interatrial pressure vent 200 in the position shown in Figure20.
(01781 Now referring to Figure 21, an interatrial pressure vent 300 of thc present invention is shown. In embodiments, flange segments 302a-h and 303a-h can be formed with alternating length to reduce interference between flange segments 202a-h and 203a-h during handling, folding and loading. In embodiments radiopaque markers 318 and 319 protrude into the inner cylindrical shape of the stowed position of thc intcratrial pressure vent 300 and alternating flange segments 302a, c, e, and g are longer than flange segments 302 b, d, f and h, and correspondingly, flange segments 303b, d, f and h arc longer than flange segments 303a, c, c and g by at least the width of the radiopaque marker. In embodiments, alternating flange segments 302a, c, c and g are longer than flange segments 302 b, d, f and h and, correspondingly, flange segments 303b, d, f and h are longer than flange segments 303a, c, c and g by at least 1 mm. In onc aspect the alternating flange segments 302a, c, e and g are longer than flange segments 302 b, d, f and h and, correspondingly, flange segments 303b, d, f and g are longer than flange segments 303a, c, c and g by at least 2% of the overall length of interatrial pressure vent 300 in the position shown in Figurc21.
10179j Referring now to Fig 22 and Fig 23, the body element 401 of an interatrial pressure vent with integral thrombus filter and retrieval cone 442 of the present invention is shown. In embodiments, conical struts 444 are affixed to body clement 401 at attachment points 446 and converge at apex 450. In embodiments, conical struts 444 comprise single beams of similar material to flange segments 402 and 403 and can bc attached to the body clement or formed at the same time as the body element using techniques described in this specification, and are thus integral with the remainder of the device. In embodiments the space between adjacent struts 444 is about 2mm. In embodiments, the space between adjacent struts 444 is about 4 mm.
As can be appreciated, conical struts 444 will protrude into the right atrium of the patient after implant and spaces between conical struts will function to block the passage of solid material larger than the space between adjacent struts 444.
This will provide the function of preventing emboli that are larger than the space between the adjacent struts 444 from passing from the right atrium to the left atrium.

-45-10180I Referring again to Fig 22 and Fig 23, in embodiments thc shape of the conical struts 444 is not straight. In embodiments the shape of the conical struts 444 can be concave when viewed on end as depicted in Fig 22. In embodiments the conical struts can be curved in a direction away from the chord formed between the apex 450 and the attachment points 446. In embodiments there can be a hole 451 through apex 450 large enough to receive a retrieval snare (not shown). It can be appreciated that conical struts 444 and apex 450 can be used to aid retrieval of thc interatrial pressure vent from a patient at some timc after the implant procedure using a mcthod as follows: A catheter tube with an internal lumen at least as large as apex . 450 can be placed into the patients right atrium using standard techniques and imaging equipment. A retrieval snare can be fabricated from the proximal end of a guidcwire bent sharply by about 180 degrees and this snare can be inserted through the catheter tube and advanced into the patient's right atrium and with the assistance of fluoroscopy advanced through hole 451 or around conical struts 444. Once the retrieval snare is engaged in this manner, it will be possible to retract the interatrial pressure vent by advancing a catheter tube while holding slight tension on the snare and thereby guide the catheter tube over apex 450 and onto conical struts 444.
As the catheter tube continues to advance, with some tension on the snare it will be possible to force the conical struts inward, thereby forcing the flange segments 402 to begin folding inwards. When the conical struts are nearly completely in thc catheter tube, the catheter tube can be held in a stationary position and the snare wire retracted against it, thereby causing the attachment points 446 between the conical struts 444 and the flange segment 402 to be retracted into the catheter. Flange segments 402 can begin to be retracted into the catheter at this point and the distal ends of flange segments 402 can be diverted toward the patients left atrium but will also fold inward and into the catheter. Once the flange segments 402 are inside of the catheter tube, the snare can be held stationary and the catheter tube can be advanced further, through the interatrial septum and over flange segments 403. Once the flange segments arc retracted into the catheter, the catheter and snare can be moved together to retract thc interatrial pressure vent into the patient's right atrium and out through thc pathway through which it was introduced.
101811 Referring now to Figures 24 and 25 an alternate embodiment of interatrial pressure vent 500 is shown. In embodiments, flow control element 504 is comprised of leaflets 541a-c. Body element 501 is comprised of core segment 506 and flange

- 46 -segments 502a-I and 503a-I ( not fully visible in Fig 25); the number of flange segments being a multiple of the number of leaflets. This configuration improves the symmetry of strain against the flow control leaflets and also improves the uniformity of motion by the flow control element to changes in blood flow.
101821 In embodiments the number of leaflets comprising the flow control clement is three and the number of flange segments on each side of the core segment is twelve. In embodiments, the number of leaflets comprising the flow control clement is three and the number of flange segments on each side of the core segment is nine. In embodiments, the number of leaflets comprising the flow control element is three and thc number of flange segments on each side is six.
101831 In embodiments, the number of leaflets comprising thc flow control element is three and the number of flange segments on each side is three. In embodiments, the number of leaflets comprising the flow control element is three, the number of flange segments on one side of the core segment is twelve and the number of flange segments on the other side of the core segment is nine. In embodiments, the number of leaflets comprising the flow control element is three, the number of flange segments on one side of the core segment is twelve and the number of flange segments on the other side of the core segment is six.
101841 In embodiments, thc number of leaflets comprising the flow control element is three, the number of flange segments on one side of the core segment is twelve and the number of flange segments on thc other side of the core segment is three. In embodiments, thc number of leaflets comprising the flow control element is three, the number of flange segments on one side of the core segment is nine and the number of flange segments on the other side of the core segment is six. In embodiments, the number of leaflets comprising the flow control clement is three, the number of flange segments on one side of the core segment is ninc and the number of flange segments on the other side of the core segment is three.
101851 In embodiments, the number of leaflets comprising the flow control element is three, the number of flange segments on one side of the core segment is six and the number of flange segments on thc other side of the core segment is three. In embodiments, the number of leaflets comprising the flow control element is two and the number of flange segments on each side of thc core segment is twelve. In embodiments, the number of leaflets comprising the flow control element is two and the number of flange segments on each side of the core segment is tcn. In

- 47 -embodiments, the number of leaflets comprising the flow control element is two and thc number of flange segments on each side of the core segment is eight.
[01861 In embodiments, the number of leaflets comprising thc flow control element is two and the number of flange segments on each side of thc corc segment is six. In embodiments, the number of leaflets comprising thc flow control element is two and the number of flange segments on each side of the core segment is four. In embodiments, thc number of leaflets comprising the flow control element is two and the number of flange segments on each side of the core segment is two.
101871 In embodiments, the number of leaflets comprising the flow control element is two, the number of flange segments on one side of thc core segment is twelve and the number of flange segments on the othcr side of thc core segment is ten.
In embodiments, the number of leaflets comprising the flow control element is two, the number of flange segments on one side of the core segment is twelve and the number of flange segments on the other side of the core segment is eight. In embodiments, the number of leaflets comprising the flow control element is two, the number of flange segments on one side of the core segment is twelve and the number of flange segments on the other side of the core segment is six.
10188i In embodiments, the number of leaflets comprising thc flow control element is two, the number of flange segments on one side of the core segment is twelve and the number of flange segments on thc other side of the core segment is four. In embodiments, the number of leaflets comprising the flow control element is two, the number of flange segments on one side of thc core segment is twelve and the number of flange segments on the other side of the core segment is two. In embodiments, the number of leaflets comprising the flow control element is two, the number of flange segments on one side of thc core segment is ten and the number of flange segments on the other sidc of the core segment is eight.
f0189] In embodiments, the number of leaflets comprising thc flow control clement is two, the number of flange segments on one side of the core segment is ten and the number of flange segments on the other side of the core segment is six. In embodiments, the number of leaflets comprising the flow control element is two, the number of flange segments on one side of thc core segment is ten and the number of flange segments on the other side of the core segment is four. In embodiments, the number of leaflets comprising the flow control element is two, thc number of flange

- 48 -segments on one side of the core segment is ten and the number of flange segments on thc othcr side of the core segment is two.
101901 In embodiments, the number of leaflets comprising the flow control element is two, the number of flange segments on one side of the core segment is ten and the numbcr of flange segments on the other side of the core segment is two. In embodiments, the numbcr of leaflets comprising the flow control clement is two, the number of flange segments on one side of the core segment is eight and the number of flange segments on the other side of thc core segment is six. In embodiments, the number of leaflets comprising the flow control element is two, the number of flange segments on one side of the core segment is eight and thc number of flange segments on the other side of the core segment is four.
101911 In embodiments, the number of leaflets comprising thc flow control element is two, the number of flange segments on one sidc of the core segment is eight and the number of flange segments on the other side of the core segment is two.
In embodiments, the number of leaflets comprising the flow control element is two, the number of flange segments on one side of the core segment is six and the number of flange segments on the other side of the core segment is four. In embodiments, the number of leaflets comprising the flow control element is two, the number of flange segments on one side of the core segment is six and the numbcr of flange segments on the other side of the core segment is two.
101921 In embodiments, the number of leaflets comprising thc flow control element is two, the number of flange segments on one side of the corc segment is four and the number of flange segments on the other side of the core segment is two.
[01931 Figure 26 shows and alternate embodiment wherein the corc segment is ovular rather than circular and thus the core segment is a cylindroid or elliptic cylinder rather than a simple cylinder. This embodiment is more conducive to a bicuspid (or "duckbill", bivalve, or two-leaflet) configuration for the flow control element. The duckbill configuration is generally referred to as flow control clement 104 in this figure. Thc inventors have found that thc bi-valve configuration is able to open more fully when coupled with a corc segment in the shape of a cylindroid.
10194) Figures 27 and 27A show another embodiment of an interatrial device having intermediate flange segments for a more secured fit against the septa!
wall. In embodiments, the intermediate flange segments are part of another a third annular flange situated on the same side of the scptal wall as onc of the other flanges.

- 49 -Reference numerals 6000 through 6040 refer to steps in the deployment of such an embodiment and will be discussed in connection with the structural features of the embodiment to illustrate this embodiment's utility and operation. The deployment process is similar to those described above, and to any commonly-known catheter based delivery process and as such the details of thc process will not be discussed herein. Steps 6000 to 6020 show the deployment process steps proceeding in much the same manner as described herein. At step 6030, intermediate flange segments 602 and 604 of intermediate (or third) annular flange are deployed on the RA side.
In this embodiment, intermediate flange segments 602 and 604 arc shorter than the majority of the flange segments of the RA-side flange. As such, segments 602 and 604 arc deployed prior to other longer segments and contact the septa' wall 107 at points closer to the septal opening than thc contact points of the longer segments.
In this manner, the intermediate segments 602 and 604 (and the flange which they comprise) provide increased stability of the device. Any number of intermediate segments may be used although it is preferable to have at least two. As with other embodiments, the stiffness of thc intermediate segments may be altered so as to differ from other flange segments of the device to avoid damage to the septa' wall, i.e., lesser stiffness/greater flexibility, or to provide increased stability, i.e., greater stiffness/lesser flexibility.
The choice of stiffness/flexibility variations must be balanced against the desired goals.
101951 Figure 27A is a side elevational view of embodiment discussed in connection with Figure 27. In Figure 27A the pressure venting device in its stowed configuration. Flanges 10') and 103 ,,re shown with the flnge segments that comprise them (flange segments not individually labeled). Core segment is again shown as 106. At a point between the end of the core segment 106 and proximal end of thc RA side flange segment 102, the intermediate segments (collectively referred to as 600) emerge. Intermediate segments may be integral with the venting device or attached thereto in the manners described above.
101961 In other embodiments, the flow control element is configured to direct the blood flow in a desired direction. Figures 28A through 28C show such embodiments.
In Figure 28A interatrial device 100 is shown implanted in the atrial septum 107 of the heart in the same manner as shown in Figure I. Flow control element 104 is configured to aim the, shown in this figure as in the direction toward the superior \feria cava. Figures 28B and 28C show a more detailed view of embodiments that

- 50 -WO 2010/129()89 enable the flow to be directed in a desired direction. As shown in Figure 2813, flow control element comprises a baffle-like flange 104a that extends at a downward angle and in the corresponding direction. In use, such embodiment directs the flow downward. Figure 28C shows an embodiment where the flow is directed upward.
The valve material (e.g. material for leaflets) of the present invention can be sized and secured to thc 100 in manner to direct the flow. For example, the flow control element may contain a curved tubular member whose opening points toward the direction of flow, or the flow control element may otherwise comprise an opening directed at the arca of interest. In embodiments with baffles, the stiffness of the baffle 104a may be varied, for example, made stiffer. The length of thc baffle can also be varied depending on the desired flow direction. The baffle can be a separate member attached to the flow control element or it may be made of thc material and/or integral with the remainder of the flow control clement.
101971 Figures 29A
through C show exit profile shapes of the flow control element 104. In these figures, the flow control element 104 is being viewed from the RA side and thus the direction of flow is understood to coming out of the page at an angle substantially normal to the page. If the flow control element is a valve as described herein, folding and suturing patterns may be employed to achieved these exit profile shapes. In other embodiments, the end of the flow control clement may be provided with a plate, or a partially frustoconical end piece, having an opening defining the two-dimensional shape shown in the Figure. The skilled artisan will appreciate that other cxit profile shapes may be fashioned. The selection of an exit profile shape may provide advantages such as directing flow, preventing thrombi from moving across the septa] divide, and/or reducing injury to surrounding tissue.
101981 Another embodiment of the invention is shown in Figure 30. In this embodiment, thc core segment 106 and flanges 102 and 103 of the device arc substantially similar those described herein. Instead of the flow control elements described above (or in addition thereto) a tube-like member 700 is secured to the core segment 106. The tube member 700 is attached to the core segment 700 in a manner to allow thc RA end of tube to extend into the RA in an axial direction, thus the tube's length must be sufficient to extend a distance into the RA. It has been found that the tube 700 configured in this manner prevents embolic particles from entering thc tube and crossing over the septa] divide into the LA. The distance that the tube extends into the RA and beyond the plane of the RA-side flange opening (indicated

-51 -by dotted line) should be at least a lmm but may be up to 2cm in preferable embodiments. Even at relatively short lengths (such as where the tube extends only a few millimeters into the RA), the inventors have noted the surprisingly unexpected result of a reduction of embolic particles passing through. This is due to, in part, the tendency of embolic particles to collect along the surface of the septal wall and move toward the septa! opening (or opening of an implanted device) with each cycle of the heart. By extending away from the septal wall 107, the tube provides an effective barrier to the embolic particles that would otherwise travel toward and possibly through the septal opening.
[0199] Although the present invention has been described and illustrated in the foregoing exemplary embodiments, it is understood that the present disclosure has been made only by way of example, and the scope of the claims should not be limited by particular embodiments set forth herein, but should be construed in a manner consistent with the specification as a whole.

- 52 -

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR
PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A device for treating a heart condition in a patient, said device being configured to be implanted into the atrial septum of the patient's heart, the patient's heart comprising a left atrium and a right atrium, the device comprising:
a cylindrical core segment defining a passage;
a first annular flange adapted to engage a first surface of the atrial septum;
a second annular flange adapted to engage a second surface of the atrial septum, and a flow control element biased to be partially open when the pressure in the left atrium is equal to the pressure in the right atrium and to close upon an occurrence of a pressure differential between the left and the right atrium.

2. The device of Claim 1 wherein the flow control element comprises a valve.

3. The device of Claim 1 wherein the first surface of the atrial septum is in the right atrium.

4. The device of Claim 1 wherein the second surface of the atrial septum is in the left atrium.

5. The device of Claim 2 wherein the valve is adapted to be flappable during the cycle of the heart.

6. The device of Claim 2 wherein the valve is adapted to resonate with the cycle of the heart.

7. The device of Claim 1 wherein the pressure in the right atrium is greater than the pressure in the left atrium.

8. The device of Claim 7, wherein said pressure differential is at least 2mm Hg.