Patent Description:
During the past decade, the number of coronary deaths in the United States has steadily decreased thanks to advancements in medical science and treatment, but the relative number of heart failure deaths has increased, indicating that more people are living with a high risk of heart failure than ever before. Generally, heart failure occurs when the heart cannot supply enough blood to the body. As a result, lower volume output leads to a higher filling pressure in the left heart to help compensate for the lack of output. Lower volume output also causes lower organ perfusion, including a reduction in kidney or renal perfusion. Reduced kidney perfusion can result in a retention of excess fluid. An acute decompensation episode is when fluid levels rise and/or vascular blood distribution declines to a state that causes the patient to experience fatigue and dyspnea (trouble breathing). If left untreated, this may result to serious complications and death.

It has been observed that heart failure primarily initiates as a result of left-side heart issues. In a normal healthy heart, oxygenated blood is first carried from the pulmonary veins, through the left atrium, into the left ventricle, and into the aorta, after which the blood is carried throughout the body. Thereafter, deoxygenated blood is carried from the two vena cavae into the right atrium, through the right ventricle, and into the pulmonary arteries, which then carry the blood into the lungs for oxygenation. The pumping performance of the left ventricle can be affected by the thickening/thinning of the left ventricular wall or by the aortic/mitral valve damage, causing less blood to be pumped to the rest of the body.

Advancements in effective treatment of heart failure in patients, including diagnosing and proactively avoiding the onset of heart failure, remain to be realized. Relevant prior art is disclosed in <CIT>, <CIT>, <CIT> and <CIT>.

According to the present invention there is provided an implantable medical device, comprising:.

Further aspects of the invention are defined in the dependent claims.

The foregoing Examples are just that, and should not be read to limit or otherwise narrow the scope of any of the inventive concepts otherwise provided by the instant disclosure. While multiple examples are disclosed, still other embodiments will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative examples. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature rather than restrictive in nature.

Persons skilled in the art will readily appreciate that various aspects of the present disclosure can be realized by any number of methods and apparatuses configured to perform the intended functions. It should also be noted that the accompanying drawing figures referred to herein are not necessarily drawn to scale, but may be exaggerated to illustrate various aspects of the present disclosure, and in that regard, the drawing figures should not be construed as limiting.

This disclosure is not meant to be read in a restrictive manner. For example, the terminology used in the application should be read broadly in the context of the meaning those in the field would attribute such terminology.

With respect terminology of inexactitude, the terms "about" and "approximately" may be used, interchangeably, to refer to a measurement that includes the stated measurement and that also includes any measurements that are reasonably close to the stated measurement. Measurements that are reasonably close to the stated measurement deviate from the stated measurement by a reasonably small amount as understood and readily ascertained by individuals having ordinary skill in the relevant arts. Such deviations may be attributable to measurement error or minor adjustments made to optimize performance, for example. In the event it is determined that individuals having ordinary skill in the relevant arts would not readily ascertain values for such reasonably small differences, the terms "about" and "approximately" can be understood to mean plus or minus <NUM>% of the stated value.

Certain terminology is used herein for convenience only. For example, words such as "top", "bottom", "upper," "lower," "left," "right," "horizontal," "vertical," "upward," and "downward" merely describe the configuration shown in the figures or the orientation of a part in the installed position. Indeed, the referenced components may be oriented in any direction. Similarly, throughout this disclosure, where a process or method is shown or described, the method may be performed in any order or simultaneously, unless it is clear from the context that the method depends on certain actions being performed first.

Various examples relate to noninvasive methods of monitoring cardiac pressure (e.g., left atrial pressure, or "LAP") in heart failure patients. Such monitoring may facilitate early warning of acute decompensation events, improved options for controlling cardiac pressure (e.g., LAP), among other potential advantages. Some examples relate to a heart failure management device that provides both titratable device-based therapy and hemodynamic monitoring. In some implementations, the heart failure management device includes a controllable cardiac shunt (e.g., intra-atrial shunt) and a sensor system for continuous noninvasive cardiac pressure measurement (e.g., LAP measurement), where flow through the shunt is controlled based upon cardiac pressure measurements from the sensor system. In some examples, the heart failure management device operates initially in a monitoring mode, and if symptoms worsen, controllable cardiac shunt is operable to modify cardiac pressure.

<FIG> shows an implantable medical device <NUM>, according to some embodiments. As shown, the implantable medical device <NUM> has a control unit <NUM> and an occlusion assembly <NUM> controlled and maintained by the control unit <NUM>. The occlusion assembly <NUM> is configured to be implanted in an organ wall (e.g., a septum of a heart) and includes one or more sensor assemblies <NUM> as well as an actuation mechanism <NUM>. The control unit <NUM> includes a receiver <NUM> which receives from the sensor assemblies <NUM> physiologic parameter information data as measured by the sensor assemblies <NUM>, and a processing unit <NUM> coupled to the receiver <NUM> which is optionally configured to analyze the physiologic parameter information received by the receiver <NUM>.

The processing unit <NUM> can be a central processing unit (CPU), a system-on-a-chip (SoC), or any suitable processor. In some examples, the processing unit <NUM> completes analysis of the physiologic parameter information and determines to send a control signal to the actuation mechanism <NUM> associated with the occlusion assembly <NUM> to control the physiologic parameter within the heart.

The purpose of the actuation mechanism <NUM> is to open the occlusion assembly <NUM> to allow for a flow of fluid therethrough. In some embodiments, the actuation mechanism <NUM> is configured to activate when the sensor assemblies <NUM> detect certain conditions within the heart. In one example, the occlusion assembly <NUM> may be placed in a wall separating two chambers of the heart, such as the atrial wall. When the sensor assemblies <NUM> detect a differential between the blood pressure measurements within the left atria (also known as the "left atrial pressure" or LAP) and the right atria (also known as the "right atrial pressure" or RAP) beyond a threshold value, the actuation mechanism <NUM> may be activated in response to the elevated blood pressure differential to reduce the differential between the left and right atrium blood pressures. In some examples, the sensor assemblies <NUM> detect a single physiological measurement. In some examples, the sensor assemblies <NUM> detect a relative or absolute measurement.

In one example, the pressure measurements taken by the sensor assemblies <NUM> can be converted into a ratio of LAP to RAP. In general practice, an ideal ratio of LAP to RAP is <NUM>:<NUM> is desirable. Therefore, any ratio that is significantly smaller or larger than the desired ratio would pose a threat to the health of the heart, so the actuation mechanism <NUM> is activated to let some of the blood flow from one atrium to the other atrium, as appropriate, to bring the ratio closer to the desirable ratio. In another example, the threshold value may be determined by the physician who then decides under which conditions should the actuation mechanism <NUM> be activated. In another example, data from a single sensor assembly may be reported and this data used by a physician (or algorithm) to determine whether the actuation mechanism should be activated. It should be noted that other physiologic measurements may be used to make this decision, as explained below.

In some embodiments, the control unit <NUM> is configured to be located external to the body, as shown in <FIG> for example. For example, the receiver <NUM> is optionally configured to receive the information wirelessly and the processing unit <NUM> is optionally configured to send the control signal wirelessly. The actuation mechanism <NUM> may be activated in response to receiving the control signal, such as an activation signal transmitted by the processing unit <NUM>. In this example, the actuation mechanism <NUM> may also be coupled to a receiver capable of receiving such signal from an external source.

<FIG> shows an implantable medical device <NUM>, according to some embodiments. The implantable medical device <NUM> includes a fluid shunt <NUM> adapted to extend through an organ wall <NUM> (e.g., a septum) separating a first cavity <NUM> (e.g., a first heart chamber) and a second cavity <NUM> (e.g., a second heart chamber) within a body of a patient. In some examples, the cavities are the left and right atria or the left and right ventricles, for example. In another example, one or more of the cavities are an aorta, a vena cava, or other vascular structure.

In some examples, the fluid shunt <NUM> includes a first portion <NUM> adapted to extend into the first cavity <NUM>, a second portion <NUM> adapted to extend into the second cavity <NUM>, and an intermediate portion <NUM> interconnecting the first portion <NUM> and the second portion <NUM>. The fluid shunt <NUM> also has a lumen <NUM> extending through the intermediate potion <NUM> between first portion <NUM> and the second portion <NUM>. The lumen <NUM> is adapted to provide a fluid path between, or to fluidly couple, the first cavity <NUM> with the second cavity <NUM>.

In some embodiments, the first portion <NUM> includes a first flange <NUM>. The first flange <NUM> may be annular in shape, having a first aperture <NUM> and including a first flange support <NUM> and a first flange cover <NUM>. The first flange support <NUM> can be a resilient framework including one or more frame elements, which may be wound, woven, braided, cut, or otherwise formed. In various examples, the first flange support <NUM> is formed of a shape memory material, such as a shape memory alloy (e.g., a nickel-titanium alloy). The first flange cover <NUM> optionally includes a membrane material (e.g., an ePTFE membrane) or other biocompatible material as desired. In some examples, the first flange cover <NUM> is configured to promote or inhibit tissue ingrowth and/or is biodegradable under physiologic conditions over time.

<FIG> show different embodiments and examples of the flanges as previously introduced. <FIG> shows the first flange <NUM> according to an embodiment where the first flange <NUM> engages with the organ wall <NUM> and is attached to an antenna <NUM>. A sensor assembly <NUM> attaches to the antenna <NUM>, and the antenna <NUM> is operative to send the physiologic measurement information provided by the sensor assembly <NUM>. In some embodiments, an occlusion assembly <NUM>, as explained below, is also attached to the antenna <NUM>. The antenna <NUM> is operative to receive the control signal sent to the occlusion assembly <NUM>, or more specifically to the actuation mechanism <NUM> of the occlusion assembly <NUM>. In one example, the implantable medical device <NUM> has a second flange <NUM> at the second portion <NUM> with a second flange cover <NUM> to prevent fluid flow between the lumen <NUM> and a second cavity <NUM>. In some embodiments, the first flange cover <NUM> and/or the second flange cover <NUM> include a composite membrane material, such as a polymer membrane. In one example, the polymer membrane is expanded polytetrafluoroethylene (ePTFE). In another example, the membrane can be any other suitable fluoropolymer, thermoplastic polymer, elastomer, biopolymer, fabric, textile, etc. In some examples, the second flange <NUM> has a configuration that is similar, if not identical, to that of the first flange <NUM>.

<FIG> show a first frame portion <NUM> according to an embodiment. In some examples, the first frame portion <NUM> forms part of the first flange <NUM> of the implantable medical device <NUM>. The first frame portion <NUM> may be covered by, or otherwise support flange cover <NUM> which may be configured to be impermeable to bodily fluids such as blood under physiologic conditions to act as a separator to help prevent fluid flow between the lumen <NUM> and the first cavity <NUM>. As shown, the first frame portion <NUM> can include one or more outer lobes (e.g., a first outer lobe 406a, a second outer lobe 406b, and a third outer lobe 406c) and an inner frame portion <NUM> (which in this example defines three inner lobes 402a, 402b, and 402c). Each of the lobes 406a, 406b, and 406c may be attached to the inner frame portion <NUM> such that the lobes are equally spaced around the inner frame portion <NUM>. In some instances, the lobes may be attached to the inner frame portion <NUM> and/or to adjacent lobes at attachment points 408a, 408b, and 408c. For example, in some instances, the first lobe 406a is attached to the second lobe 406b at attachment point 408a, the second lobe 406b is attached to the third lobe 406c at attachment point 408b, and the third lobe 406c is attached to the first lobe 406a at attachment point 408c. Although <FIG> are described with reference to three lobes and three attachment points, the first frame portion <NUM> can have any number of lobes and respective attachment points as desired.

When present, the inner frame portion <NUM> can be any shape as desired. For example, in some instances, the inner frame portion <NUM> is substantially circular or substantially triangular (as shown in <FIG>). In some instances, the inner lobes 402a, 402b, and 402c may extend into the first, second and third lobes 406a, 406b, 406c to define the shape of the inner frame portion <NUM>. In some examples, the first frame portion <NUM> includes the sensor assembly <NUM> attached thereto. In some examples, the sensor assembly <NUM> is operatively coupled to the antenna <NUM> as shown in <FIG>.

Though not shown in <FIG>, and similarly to the first flange <NUM>, the second flange <NUM> of the implantable medical device <NUM> can include a second frame portion that has the same or a different number of lobes as the first frame portion <NUM>. For example, in some instances, the first and second frame portions each have three lobes. In other instances, the first frame portion <NUM> may include three lobes while the second frame portion includes two, four, five, or more lobes. In some instances, the first frame portion <NUM> can have lobes that are larger, smaller, and/or a different shape than the lobes of the second frame portion. Furthermore, in some examples, the first frame portion <NUM> can include one or more sensor assemblies (e.g., <NUM> and <NUM>) and the antenna <NUM>, as shown in <FIG>.

Furthermore, though not shown in <FIG>, in certain instances, the implantable medical device <NUM> may include a pattern of structural frame elements or other structural features that form the first flange <NUM> and/or the second flange <NUM>. The pattern of structural frame elements may be arranged (e.g., project from) inside inner lobes 402a, 402b, and 402c, and may be included in any of the lobes of devices discussed herein. If desired, the pattern of structural frame elements can be arranged to form an open cell pattern. For example, the pattern of structural frame elements can form a diamond cell pattern in the inner lobes 402a, 402b, and 402c that collapse and open during load and deployment of the implantable medical device <NUM> in a catheter. The pattern of structural frame elements may enhance radial strength during deployment and facilitate arrangement of the implantable medical device <NUM> in a deployed, or otherwise operative shape.

<FIG> shows the first flange cover <NUM> after the actuation mechanism <NUM> creates a first aperture <NUM> in the cover <NUM> to allow for fluid flow through the lumen <NUM>. In some embodiments, the first aperture <NUM> is formed through mechanical or interventional procedures. In some embodiments, the first aperture <NUM> is formed through non-invasive procedures.

Referring back to <FIG>, in some embodiments, the second portion <NUM> includes the second flange <NUM>. The second flange <NUM> may be annular in shape, having a second aperture <NUM> and including a second flange support <NUM> and a second flange cover <NUM>. The second flange support <NUM> can also be a resilient framework including one or more frame elements, which may be wound, woven, braided, cut, or otherwise formed. In various examples, the second flange support <NUM> is formed of a shape memory material, such as a shape memory alloy (e.g., a nickel-titanium alloy). The second flange cover <NUM> optionally includes a membrane material (e.g., an ePTFE membrane) or other biocompatible material as desired. In some examples, the second flange cover <NUM> is configured to promote or inhibit tissue ingrowth and/or is biodegradable under physiologic conditions over time.

In some embodiments, the intermediate portion <NUM> of the fluid shunt <NUM> includes a tubular member <NUM> and an intermediate support <NUM> configured to help maintain the shape of the tubular member <NUM> against compression and/or distortion forces exerted by the patient anatomy (e.g., the wall <NUM>) and/or physiologic processes (e.g., blood pressure). The intermediate support <NUM> can also be a resilient framework including one or more frame elements, which may be wound, woven, braided, cut, or otherwise formed. In various examples, the intermediate support <NUM> is formed of a shape memory material, such as a shape memory alloy (e.g., a nickel-titanium alloy). The tubular member <NUM> optionally includes a membrane material (e.g., an ePTFE membrane) or other biocompatible material as desired. In some examples, the tubular member <NUM> is configured to promote or inhibit tissue ingrowth and/or is biodegradable under physiologic conditions over time.

As indicated generally in <FIG>, the implantable medical device <NUM> also includes the occlusion assembly <NUM>, as mentioned above, associated with the fluid shunt <NUM>. In some examples, the occlusion assembly <NUM> is adapted to selectively occlude flow through the lumen <NUM> of the fluid shunt <NUM>. For example, the occlusion assembly <NUM> can be configured to be activated (via physical, manual intervention or via remote or automatic means) to adjust flow through the lumen <NUM> of the fluid shunt <NUM>.

In some examples, the actuation mechanism <NUM> is configured to be actuated to permit fluid flow through the lumen <NUM>, or to permit increased or decreased fluid flow through the lumen <NUM>. In some examples, the actuation mechanism <NUM> is selectively activated to increase and decrease flow, for example by being actuatable to open or narrow the lumen <NUM>. The actuation mechanism <NUM> is optionally positioned at the first portion <NUM>, the second portion <NUM>, and/or the intermediate portion <NUM>. The actuation mechanism <NUM> may be "one-way" actuatable, in that the actuation mechanism <NUM> begins at a no-flow, or low-flow condition, and then can be opened (e.g., entirely or in stages), to increase flow. In other embodiments, the actuation mechanism <NUM> can both increase and decrease flow through the fluid shunt <NUM>.

In one example, the actuation mechanism <NUM> includes a needle or other suitable puncturing component to mechanically penetrate one or both of the flange covers <NUM> and <NUM>. In one example of an interventional procedure, a needle is led to the location of the implantable medical device <NUM> by a catheter, and the needle is used to form the first aperture <NUM> by puncturing the first flange cover <NUM> and the second aperture <NUM> by puncturing the second flange cover <NUM>. Other interventional procedures include mechanical, thermal, laser, ultrasound, and inductive methods.

In one example shown in <FIG>, the actuation mechanism <NUM> is attached to the antenna <NUM>. The membrane defining the first flange cover <NUM> is made of three flap elements <NUM>, <NUM>, and <NUM> that are under radial tension, with a wire <NUM> fixing the three flap elements together with a stitch <NUM> as shown to prevent the radial tension from causing the flap elements to move toward the outer edge of the first flange <NUM>. The sensor assembly <NUM> is located on the antenna <NUM>. Upon receiving the actuation signal from the control unit <NUM>, the actuation mechanism <NUM> pulls the wire <NUM> to cause the flap elements <NUM>, <NUM>, and <NUM> to be pulled back toward the outer edge, thereby creating the first aperture <NUM> as shown in <FIG>. The wire <NUM> can be made of any suitable material. In some examples, the wire <NUM> is a thread made of polymers such as nylon or PTFE. In some examples, the wire <NUM> is made of a conductive material, such as stainless steel or nickel-titanium alloy, among others. In one example, the same actuation mechanism may also be attached to the second flange cover <NUM>, with the second flange cover <NUM> also made of similar flap elements. In one example, the number of flap elements may be two. In other examples, the number of flap elements may be four or more.

Various additional or alternative actuation mechanisms are contemplated. In some examples, the wire <NUM> is conductive, and upon receiving the actuation signal from the control unit <NUM>, the occlusion assembly <NUM> applies a voltage to the wire <NUM> to cause the wire <NUM> to undergo electrolytic degradation. After undergoing sufficient degradation, the wire <NUM> breaks or dissolves and can no longer hold the flap elements <NUM>, <NUM>, and <NUM> together. As such, the flap elements <NUM>, <NUM>, and <NUM> retract or open from the initial position shown in <FIG>, thereby creating the first aperture <NUM> as shown in <FIG>.

In some examples, the actuation mechanism <NUM> is external to the body, such as an extracorporeal energization unit <NUM>. <FIG> illustrates the implantable medical device <NUM> or <NUM>. Energy is inductively supplied to the implantable medical device using the extracorporeal energization unit <NUM> in a treatment system according to an embodiment. The energization unit <NUM> can include an extracorporeal induction energy source which supplies power to the implanted medical device so that electrical energy can electrolytically degrade an element <NUM> thereby forming the first aperture <NUM>, converting the device to an open configuration. In some examples, the control unit <NUM> is configured to be located external to the body and controls the extracorporeal energization unit <NUM>. In some embodiments, the treatment system which operates to control the first aperture <NUM> in the implantable medical device <NUM> includes one or more of: an internal induction energy receiver, an ultrasonic energy source, a laser energy source, a radiofrequency (RF) energy source, and/or another type of energy source for activating the occlusion assembly <NUM>. Furthermore, in some embodiments, when the first aperture <NUM> is formed and fluid flow is allowed within the lumen <NUM>, the implantable medical device <NUM> exhibits different resonant frequencies based upon a flow rate through the lumen <NUM>. The resonant frequency can be measured using one or both of the sensor assemblies <NUM> and <NUM> coupled to the implantable medical device <NUM>. In one example, the resonant frequency measured by the receiver <NUM> is converted to a physiologic parameter such as the fluid flow rate by the processing unit <NUM>. In one example, both of the sensor assemblies <NUM> and <NUM> are pressure sensors, so the flow rate of fluid through the lumen <NUM> is estimated based upon the lumen's dimensions, the pressure differential, and the known fluid dynamic characteristics of the fluid, which may be blood. Additional or alternative sensing features are contemplated. In some examples, a shift in resonant frequency measured by the sensor assembly <NUM> or <NUM> provides verification that the lumen <NUM> is successfully opened to allow fluid flow therethrough.

In some embodiments, the wireless extracorporeal energization includes inductive energy transfer or ultrasound energy transfer, which are nonlimiting examples of the noninvasive procedures. In one embodiment, a membrane of the flange cover <NUM> can be melted to form the aperture <NUM> after exposing the flange cover <NUM> to thermal or ultrasound energy, to produce a thermal activation mechanism. In some examples, the size of the aperture <NUM> can be adjusted by varying the amount of thermal activation. For reference, if desired, the aperture <NUM> in the flange cover <NUM> may be formed using the same method/mechanism as any of those described in association with the flange cover <NUM>, or by differing methods as desired.

In another embodiment, the flange cover <NUM> is made of at least one flap element which is controlled mechanically by the actuation mechanism <NUM>, which is in turn controlled wirelessly by the control unit <NUM>. In one example, mechanism control is accomplished by the actuation mechanism <NUM> pulling on the flap element to change the state of the flap element from a closed state to a more open state. The size of the aperture <NUM> can be adjusted by varying how much the flap element is to be displaced from the closed position. In some embodiments, the actuation mechanism <NUM> can also control the flap element to decrease the size of the aperture <NUM> by returning the position of the flap element closer to the closed position. In one example, the controlling of the at least one flap element is done by the actuation mechanism <NUM> of the occlusion assembly <NUM> applying a voltage to induce electrolytic degradation of the wire (for example, the wire <NUM> shown in <FIG>) which holds the at least one flap element in the closed state, thereby causing the at least one flap element to change from the closed state to a more open state.

In some embodiments that are configured to utilize noninvasive procedures for actuation, one or both of the covers <NUM> and <NUM> are made of a membrane that is selectively absorptive to ultrasound such that the membrane is configured to be thermally opened using an ultrasound source to adjust flow through the lumen <NUM> of the fluid shunt <NUM>. In some embodiments configured to utilizing noninvasive actuation procedures, one or both of the covers <NUM> and <NUM> are made of a membrane that is selectively absorptive to RF energy such that the membrane is thermally opened using an RF ablation source to adjust flow through the lumen <NUM> of the fluid shunt <NUM>. In some embodiments, the membrane is selectively absorptive to laser energy such that the membrane is configured to be thermally opened using a laser source. In some embodiments, the membrane or the elements (e.g., wires) holding the membrane in place are selectively and electrolytically degradable using electrical energy supplied by an induction energy source. In some examples, the electrical energy can be supplied by any suitable means such as a battery, a piezoelectric receiver exposed to an ultrasonic energy source, magnetic induction, a radiofrequency (RF) energy source, and/or another type of energy source for activating the occlusion assembly. In some embodiments, both covers <NUM> and <NUM> are actuatable utilizing similar methods. For example, the covers <NUM> and <NUM> can both be configured to open simultaneously in response to receiving energy from an external source, e.g. RF energy, laser energy, induction energy, or others.

In some embodiments, one or both of the covers <NUM> and <NUM> are under radial tension to assist with forming one or both of the apertures <NUM> and <NUM>. For example, when the cover(s) <NUM> and <NUM> are stretched, even a small opening in the covers can be enlarged when the radial tension placed from the outer edge of the covers pull the cover material surrounding the opening away from the locations of the openings in a plurality of directions. In some embodiments, the cover(s) exhibit residual stress profile to assist with forming the one or both of the apertures <NUM> and <NUM> in the cover. In some embodiments, the cover(s) are selectively openable between a plurality of sizes for the one or both of the apertures <NUM> and <NUM> to modify flow through the lumen <NUM>.

<FIG> shows a sensor system <NUM> implemented in one embodiment of the implantable medical device <NUM>. In some examples, the sensor system <NUM> includes one or more sensor assemblies <NUM> and a sensor control unit <NUM> in communication with the one or more sensor assemblies <NUM>. In one example, the one or more sensor assemblies <NUM> are active sensors that include transmitters that send out a signal and records the environmental response to the signal. In another example, the one or more sensor assemblies <NUM> are passive sensors that require external energy sources to perform physiological measurements, for example upon receipt of an input from the physical environment. The sensor control unit <NUM> includes a battery <NUM>, a receiver <NUM>, and a transmitter <NUM>. The battery <NUM> provides power for the sensor assemblies <NUM> to continue taking physiological measurements as well as for the sensor control unit <NUM> to receive and transmit data of said measurements. The receiver <NUM> receives the measurement data from the sensor assemblies <NUM>, and the transmitter <NUM> transmits the data, for example wirelessly, to the external control unit <NUM>.

In some examples, the one or more sensor assemblies <NUM> include a first sensor assembly <NUM> associated with the first portion <NUM> of the fluid shunt <NUM> adapted to sense one or more physiologic parameters in the first cavity <NUM> and a second sensor <NUM> associated with the second portion <NUM> of the fluid shunt <NUM> adapted to sense one or more physiologic parameters in the second cavity <NUM> within the heart. Although two sensor assemblies are shown and described, greater (e.g., three or more) or fewer (e.g., a single sensor) are contemplated. In one example, one or all of the sensor assemblies <NUM> are configured to sense a physiologic parameter including blood pressure levels in the respective cavities. In some examples, one or more sensor assemblies <NUM> are configured to sense the rate at which blood flows in the designated cavity within the heart. In still further examples, one or more sensors are configured to sense temperature of the blood. In still other examples, one or more sensors are configured to sense oxygen saturation of the blood.

Examples of suitable sensors capable of measuring fluid flow or pressure inside an organ include piezoelectric sensors, pressure switches, optical pressure transducers, Venturi meters, impedance monitors, and ultrasonic pressure sensors, as well as other types of electrophysiologic and hemodynamic sensors.

<FIG> shows a method <NUM> of operating the implantable medical device <NUM> according to one embodiment. In the first step <NUM>, the lumen <NUM> is extended through the wall <NUM> separating the first cavity <NUM> within the heart and the second cavity <NUM> within the heart. In one example, the fluid shunt <NUM> is passed through the wall <NUM> of the heart, including engaging flange portions, or anchors <NUM> and <NUM>, of the first portion <NUM> and the second portion <NUM> of the fluid shunt <NUM> with the wall <NUM> of the heart. In step <NUM>, the first sensor assembly <NUM> senses one or more physiologic parameters in the first cavity <NUM>. In the following step <NUM>, the flow through the fluid shunt <NUM> is adjusted by actuating the occlusion assembly <NUM> associated with the fluid shunt <NUM>.

<FIG> shows another method <NUM> of operating the implantable medical device <NUM> according to some embodiments. In step <NUM> following the aforementioned step <NUM>, the second sensor <NUM> senses one or more physiologic parameters in the second cavity <NUM> within the heart. In step <NUM>, the receiver <NUM> receives the physiologic parameters sensed by the first sensor assembly <NUM> and the second sensor <NUM>. In the next step <NUM>, the processing unit <NUM> performs analysis on the physiologic parameters received by the receiver <NUM> to generate an actuation signal. In step <NUM>, the control unit <NUM> sends the actuation signal to the occlusion assembly <NUM>. Finally, in step <NUM>, the flow through the fluid shunt <NUM> is adjusted by actuating the occlusion assembly <NUM> associated with the fluid shunt <NUM> according to the actuation signal provided by the processing unit <NUM> of the control unit <NUM>.

In some embodiments, the control unit <NUM> sends the actuation signal to the occlusion assembly <NUM> upon the first sensor assembly <NUM> and the second sensor <NUM> sensing a predetermined differential physiologic measurement such that the occlusion assembly <NUM> increases flow through the lumen <NUM> by performing one or more of the procedures as explained above.

<FIG> is an image of a first side of the implantable medical device <NUM>, where the first frame portion <NUM> of the first flange <NUM> as shown in <FIG> is visible, including a covering material for the flange cover <NUM>, in accordance with an embodiment. As shown, in some instances, the covering material <NUM> can be arranged over the opening or aperture <NUM>. Thus, the covering material <NUM> may act to slow or occlude flow through the first frame portion <NUM> as desired. In some instances, the covering material <NUM> can be arranged over the first frame portion <NUM>. In some instances, the covering material <NUM> may be attached to one or more of the first lobe 406a, the second lobe 406b, and the third lobe 406c. In some instances, the inner frame portion <NUM> serves as the second frame portion <NUM>, as shown and discussed with reference to <FIG>. In some examples, the sensor assembly <NUM> is located on one or more of the first lobe 406a, the second lobe 406b, and the third lobe 406c.

<FIG> is an image of a second side of the implantable medical device <NUM>, in accordance with an embodiment. As shown, the covering material <NUM> is arranged over the opening <NUM>. In various instances, the first, second, and third lobes 1302a, 1302b, and 1302c of the second frame portion <NUM> may or may not include the covering material <NUM>. For example, as shown, the covering material <NUM> is arranged over the opening <NUM> but not over the second frame portion <NUM>, while in other examples, the covering material <NUM> may be arranged over both the opening <NUM> and the second frame portion <NUM>, for example. In some examples, the sensor assembly <NUM> is located on one or more of the first lobe 1302a, the second lobe 1302b, and the third lobe 1302c.

<FIG> shows an implantable medical device <NUM> with two flanges <NUM> and <NUM> attached to a surface of the organ wall <NUM> according to an embodiment, where the first and second flanges are located on opposite sides of the organ wall with conduit extending through the organ wall. In one example, the organ wall <NUM> is an atrial wall between a left atrium and a right atrium of a heart, such that the first flange <NUM> is located on a surface of the atrial wall <NUM> in the right atrium, and the second flange is located on a surface of the atrial wall <NUM> in the left atrium with a conduit <NUM> extending between the two flanges <NUM> and <NUM> such that the conduit <NUM> forms the lumen <NUM> fluidly connecting the two atria of the heart.

In one example, the conduit <NUM> includes a cover material, such as a membrane that has high rigidity and stiffness, for example one made of a polymer material such as fluoroelastomer, high-density polyethylene, polyethylene terephthalate (PTE), polyvinyl chloride (PVC), polyamide, polycarbonate, polymethylpentene, polypropylene, polystyrene, polysulfone, or others, in order for the membrane to exert radial force against the wall <NUM> to prevent the lumen <NUM> from collapsing.

In some examples, the conduit <NUM> includes one or more structural elements (e.g., stent elements) made of a suitable material, such as shape memory alloy (e.g., a nickel-titanium alloy) or stainless steel, for example. As shown, the medical device <NUM> includes a cover <NUM>, such as a flexible membrane of any suitable polymer material include but not limited to ePTFE. As shown, the cover <NUM> is located or is otherwise configured to reside between the first flange <NUM> and the wall <NUM>. Additionally, the medical device <NUM> includes one or more (e.g., three) locations to place one or more sensors to perform physiological measurements within the body. In a first location <NUM>, a sensor (e.g., a pressure sensor) can be placed at the first flange <NUM> so that the sensor can perform measurements in the right atrium. In a second location <NUM>, a sensor (e.g., a flow sensor) can be placed inside the conduit <NUM> to measure the flow of fluid within the lumen <NUM>. In a third location <NUM>, a sensor (e.g., a pressure sensor) can be placed at the second flange <NUM> to perform measurements in the left atrium. In some examples, a single sensor performing a single sensing function is placed at each location, whereas in other examples, a plurality of sensors, or a sensor performing a plurality of sensing functions, can be placed at each location.

<FIG> shows the implantable medical device <NUM> as shown in <FIG> with an additional, secondary cover <NUM> (e.g., of flexible membrane material such as those previously described) according to an embodiment. In this embodiment and the embodiment shown in <FIG>, the covers <NUM> and <NUM> are selectively absorptive to RF energy such that the covers are thermally opened using an RF ablation source to adjust flow through the lumen <NUM>. In some embodiments, the covers <NUM> and <NUM> are selectively absorptive to laser energy such that each cover is configured to be thermally opened using a laser source. In some embodiments, the covers <NUM> and <NUM> are selectively absorptive to ultrasound energy such that each cover (<NUM> and/or <NUM>) is configured to be thermally opened using an ultrasound source. In some embodiments, the covers <NUM> and <NUM> or the elements (e.g., wires) holding the covers in place are selectively and electrolytically degradable using electrical energy supplied by an induction or other energy source.

<FIG> shows the implantable medical device <NUM> in a compressed configuration inside a deployment apparatus <NUM>, in accordance with an embodiment. As shown, the device <NUM> is compressed into a delivery configuration and loaded into the deployment apparatus <NUM> to be delivered to a desired treatment location within the patient's body. In certain instances, the device <NUM> is loaded into the deployment apparatus <NUM> such that the device <NUM> is completely contained within the deployment apparatus <NUM>, as shown in <FIG>. The device <NUM> can be delivered to the desired treatment location while in the delivery configuration. The first flange <NUM> is then positioned on a first side of the wall <NUM> and the flange <NUM> is positioned on a second side of the wall <NUM>. In some instances, once deployed, the central portion or the conduit <NUM> of the device <NUM> can be radially expanded or compressed/restricted to adjust the rate of fluid flow through the opening as desired. In one example, the deployment apparatus <NUM> includes a catheter or a sheath.

<FIG> shows an example of using the implantable medical device <NUM> for regulating blood pressure in accordance with an embodiment. The implantable medical device <NUM> is shown implanted within a heart H of a patient. The device <NUM> is shown arranged between the patient's left atrium LA and right atrium RA. In certain instances, the device <NUM> may be used to regulate blood flow within the heart H, for example, between the left and right atria LA, RA. As shown, the device <NUM> generally includes the first flange <NUM> arranged on a first side of a septum (e.g., within the right atrium RA), the second flange <NUM> arranged on a second side of the septum (e.g., within the left atrium LA), and the conduit <NUM> extending therethrough. In some examples, a needle may be used to create or open a trans-septal opening in the septum.

The deployment apparatus <NUM> and constraining and/or release lines (not shown) may be used to facilitate deployment of the device <NUM>. For example, the second flange <NUM> of the device <NUM> may be released first after the deployment apparatus <NUM> is advanced through the organ wall (e.g., septum) and into a desired internal cavity (e.g., the LA), and the first flange <NUM> may be released on an opposite side of the organ wall (e.g., on the RA side of the atrial septum). The conduit <NUM> can be arranged within the opening in the organ wall (e.g., the trans-septal opening). The flanges <NUM> and <NUM> as well as the conduit <NUM> may be compressed within the deployment apparatus <NUM> during delivery of the device <NUM> to the desired treatment area within the patient and subsequently expanded during deployment of the device <NUM>. After deployment, the device <NUM> can then be used to carry out one or more treatment programs on the patient. In one example, the device <NUM> detects and treats pulmonary congestion and pulmonary hypertension by taking physiologic measurements using the sensors in one or more locations within the heart. For example, if the pressure measurement within the left atrium increases with respect to the right atrium in the patient at a risk of heart failure, the sensors of the medical device <NUM> detects a condition, and the conduit <NUM> is opened by activating the occlusion assembly <NUM>, for example, to allow blood flow through the lumen <NUM>, thereby decreasing the pressure within the left atrium to a safe level.

<FIG> shows an example of an implantable medical device <NUM> for regulating blood pressure in accordance with an embodiment. As shown, the implantable medical device <NUM> includes the first frame component <NUM> and the second frame component <NUM>. The first frame component <NUM> may be configured to conform to the patient's anatomy (i.e., the first side of the septum, for example). The second frame component <NUM> may be configured to conform to the patient's anatomy (i.e., the second side of the septum). In some examples, the sensor assembly <NUM> is located on one or both of the first frame component <NUM> and the second frame component <NUM>.

In certain instances, the first frame component <NUM> includes a first set of elongate elements <NUM>, and the second frame component <NUM> includes a second set of elongate elements <NUM>. The frame components <NUM>, <NUM>, including and for example the elongate elements <NUM>, <NUM>, may be discrete and separate from one another. For example, the first frame component <NUM> forms a first side <NUM> of the device <NUM> and the second frame component <NUM> forms a second side <NUM> of the device <NUM>. The first frame component <NUM> being discrete and separate from the second frame component <NUM> does not enter into the second side <NUM> of the device and the second frame component <NUM> being discrete and separate from the first frame component <NUM> does not enter into the first side <NUM> of the device.

In certain instances, the first and second frame components <NUM>, <NUM> are non-contiguous with one another. The first and second frame components <NUM>, <NUM> being non-contiguous with one another allows the first and second frame components <NUM>, <NUM> to be distinct and separate from one another. In addition, the first and second frame components <NUM>, <NUM> are free to move, in response to movement of the patient's anatomy, separate from one another. In this manner, forces acting on one of the first and second frame components <NUM>, <NUM> are maintained within the other of the first and second frame components <NUM>, <NUM>. The forces acting on one of the first and second frame components <NUM>, <NUM> may be isolated to the frame component to which the force is acted on.

As shown, the conduit portion <NUM> is arranged between the first frame component and the second frame component. At least a portion of the conduit portion <NUM> is generally radially or circumferentially unsupported by the first and second frame components <NUM>, <NUM> within the conduit portion <NUM>. As shown in <FIG>, the conduit portion <NUM> transitions to the first side <NUM> and the second side <NUM> at approximately a <NUM> degree angle (other angles are contemplated). Bounds of the conduit portion <NUM> may be considered to be a location at which the conduit portion <NUM> transitions to the first side <NUM> and the second side <NUM>. The first and second frame components <NUM>, <NUM> extend laterally relative to the conduit portion <NUM>. In addition, the first and second frame components <NUM>, <NUM> may support the conduit portion <NUM> without substantially entering the bounds of the conduit portion <NUM>. In certain instances, the first and second frame components <NUM>, <NUM> support the conduit portion <NUM> laterally from outside of bounds the conduit portion <NUM>. Thus, the first and second frame components <NUM>, <NUM> may maintain a lumen through the conduit portion <NUM> and facilitate deployment of the conduit portion <NUM> by laterally forcing the conduit portion <NUM> open.

In certain instances, the first and second frame components <NUM>, <NUM> may impart tension to the conduit portion <NUM> to deploy and maintain the conduit portion <NUM> with a lumen therethrough. The conduit portion <NUM> may be deployed within the septum between tissue surfaces through an opening (e.g., needle stick across the septum) that has a diameter smaller than a fully deployed diameter of the conduit portion <NUM>. Tension in the conduit portion <NUM> imparted by expansion of the first and second frame components <NUM>, <NUM> may also expand the septum between tissue surfaces to a desired shunt size.

In certain instances, the conduit portion <NUM> may be substantially free of frame components. For example, because the first and second frame components <NUM>, <NUM> are non-contiguous with one another, as described above, and are arranged external to the bounds of the conduit portion <NUM>. The conduit portion <NUM> may include, for example, a membrane <NUM>, such as an expanded polytetrafluoroethylene (ePTFE) membrane, connecting the first frame component <NUM> and the second frame component <NUM>. The membrane <NUM> generally separates the first frame component <NUM> and the second frame component <NUM> by a suitable distance compatible with the patient's body. For example, the membrane <NUM> can separate the first frame component <NUM> and the second frame component <NUM> by a gap of from <NUM> to <NUM> depending on the desired treatment location within the patient's body. In addition, the conduit portion may be formed of only the membrane <NUM>. The conduit portion <NUM>, which is configured to be deployed within the septum between tissue surfaces, is free of the first frame component <NUM> and the second frame component <NUM>. The conduit portion <NUM> may include a smooth interior that facilitates blood flow therethrough without ridges from a stent element interrupting or disrupting flow. Thus, the conduit portion <NUM> may lessen the opportunity for thrombosis.

In addition to the membrane <NUM> forming the conduit portion <NUM>, the membrane <NUM> may also cover at least a portion of the first frame component <NUM>, at least a portion of the second frame component <NUM>, or at least a portion of the first frame component <NUM> and the second frame component <NUM>. In certain instances, the membrane <NUM> arranged on at least a portion of the first frame component <NUM> and/or the second frame component <NUM> is a separate membrane film (e.g., a first membrane film arranged on first frame component <NUM> and a second membrane film arranged on the second frame component <NUM>). In these instances, the membrane film or films may be coupled to the membrane <NUM> in the conduit portion <NUM>. The membrane <NUM> may be elastic to allow for expansion of the conduit portion <NUM> and to allow for movement of portions of the first frame component <NUM> and/or the second frame component <NUM> (e.g., movement of the first set of elongate elements <NUM> and/or the second set of elongate elements <NUM>).

The membrane <NUM> may span gaps between the first set of elongate elements <NUM> and/or the second set of elongate elements <NUM>. The membrane <NUM>, in certain instances, is arranged on at least a tissue engaging side of the first frame component <NUM> and a tissue engaging side the second frame component <NUM>. In these instances, the membrane <NUM> is configured to lessens frame erosion potential of the first frame component <NUM> and/or the second frame component <NUM>. The membrane <NUM> and the arrangement of the first set of elongate elements <NUM> and/or the second set of elongate elements <NUM> may conform to the tissue surfaces surrounding the septum. The first set of elongate elements <NUM> and/or the second set of elongate elements <NUM> may lay flat against the tissue surfaces.

In certain instances, each of the first set of elongate elements <NUM> may be attached to one another via the membrane <NUM> to form the first frame component <NUM>. In certain instances, the first frame component <NUM> may form a substantially flat or <NUM>-dimensional, disc-like shape, as shown. Additionally, or alternatively, the second set of elongate elements <NUM> may also be attached to one another via the membrane material <NUM> to form the second frame component <NUM>. The second frame component <NUM> may also form a substantially flat or <NUM>-dimensional, disc-like shape such that the first and second frame components <NUM>, <NUM> are substantially parallel to one another when the device <NUM> is in a deployed configuration.

In certain instances, the membrane <NUM> may be configured to promote or inhibit tissue ingrowth over at least a portion of the membrane <NUM>, or at least a portion of the membrane <NUM>. In certain instances, the membrane <NUM> is configured to promote or inhibit tissue ingrowth to cover at least a portion of the first and/or second frame components <NUM>, <NUM>, which may further promote compatibility and stability of the device <NUM> within the patient's body. The membrane <NUM> within the conduit portion <NUM> may be configured to not allow tissue ingrowth leading to increased patency. In certain instances, the membrane <NUM> is configured to promote endothelization without obstructive ingrowth within the conduit portion <NUM>. The membrane <NUM> may promote endothelization without obstructive overgrowth of tissue into the conduit portion <NUM>.

In certain instances, the device <NUM> may be capable of delivering a drug to the desired treatment location within the patient's body. For example, the device <NUM> may be capable of eluting a drug configured to modulate tissue response. In certain instances, the device <NUM> may be coated with a therapeutic coating, drug eluting material or other therapeutic material or a hydrophilic coating. In one specific example, the device <NUM> can be coated with heparin to facilitate thromboresistance and patency of the device <NUM>. Alternatively, or additionally, the device <NUM> may include paclitaxel (to modulate tissue/cellular response).

<FIG> is a perspective view of another example of an implantable medical device <NUM> for regulating blood pressure in accordance with an embodiment. As shown, each of the first set of elongate elements <NUM> may be discrete and separate from adjacent elongate elements. In other terms, the membrane <NUM> does not connect each of the first set of elongate elements <NUM> together. In this way, each of the first set of elongate elements <NUM> may move independently from one another and individually conform to the topography of the first side of the septum, thus providing a highly conformable first frame component <NUM>. Each of the second set of elongate elements <NUM> may also be discrete and separate from adjacent elongate elements. For example, each of the second set of elongate elements <NUM> may move independently from one another and individually conform to the second side of the septum, much like the first set of elongate elements <NUM> conforms to the first side of the septum. Thus, both the first and second frame components <NUM>, <NUM> are highly conformable and may conform independently of one another based on the patient's anatomy.

In certain instances, one of the first or second set of elongate elements <NUM>, <NUM> of the first and second frame components <NUM>, <NUM> may be attached to one another via the membrane <NUM> while the other set of elongate elements are unattached (e.g., they are discrete and separate from adjacent elongate elements). In other instances, only some of the first or second set of elongate elements <NUM>, <NUM> may be attached to one another, while other elongate elements of the first and second set of elongate elements <NUM>, <NUM> are not attached. Thus, the device <NUM> can be highly customizable to the patient depending on the desired treatment location within the patient, and size and/or shape of the defect, among other factors. In some examples, the sensor assembly <NUM> is located on one or both of the first frame component <NUM> and the second frame component <NUM>.

The device <NUM> is generally deployable or expandable from a delivery configuration to the deployed configuration. In some instances, the first set of elongate elements <NUM> and the second set of elongate elements <NUM> may nest within one another when the device is in the delivery configuration. This allows the device <NUM> to compress to a smaller size, for example, for delivery of the device <NUM> to a wider variety of treatment locations (e.g., through small, narrow, or convoluted passageways).

<FIG> is a side view of the implantable medical device <NUM> for regulating blood pressure, shown in <FIG>, in accordance with an embodiment. <FIG> shows the device <NUM> in the deployed configuration. As shown, the first frame component <NUM> including the first set of elongate elements <NUM> and the second frame component <NUM> including the second set of elongate elements <NUM> are positioned radially outward with respect to a longitudinal axis L of the conduit portion <NUM> when the device <NUM> is in the deployed configuration. For example, the first and second frame components <NUM>, <NUM> are positioned at first and second angles <NUM>, <NUM>, respectively. The first and second angles <NUM>, <NUM> may form approximately a <NUM>° angle with respect to the longitudinal axis L when the device is in the deployed configuration. This allows the first and second frame components <NUM>, <NUM> to be positioned parallel with and adjacent to the first and second sides of the septum. In certain instances, the first and second frame components <NUM>, <NUM> may be positioned at any angle relative to the longitudinal axis L (for example, from about <NUM>° to greater than <NUM>° with respect to the longitudinal axis L) that allows for contact with the tissue surface of the first and second sides of the septum.

In certain instances, the first and second elongate elements <NUM>, <NUM> are configured to separate from one another when the device <NUM> is in the deployed configuration. As shown in <FIG>, each of the first set of elongate elements <NUM> are discrete and separate from one another when the device <NUM> is in the deployed configuration such that each of the first set of elongate elements <NUM> may move independently from adjacent elongate elements. Each of the second set of elongate elements <NUM> may also be discrete and separate from one another when the device <NUM> is in the deployed configuration such that each of the second set of elongate elements <NUM> move independently from adjacent elongate elements. In some examples, the sensor assembly <NUM> may be located on any one or more of the first set of elongate elements <NUM>, and the other sensor assembly <NUM> may be located on any one or more of the second set of elongate elements <NUM>.

The first and second frame components <NUM>, <NUM> may maintain a lumen through the conduit portion <NUM> and facilitate deployment of the conduit portion <NUM> by laterally forcing the conduit portion <NUM> open. In addition, the lumen may be free or without the first and second frame components <NUM>, <NUM>. In this manner, the conduit portion <NUM> may facilitate re-crossing of the septum for addition procedures (e.g., left atrial appendage occluder implantation). In addition, the first and second frame components <NUM>, <NUM> may be differently configured. For example, one of the first and second frame components <NUM>, <NUM> may be flared while the other of the first and second frame components <NUM>, <NUM> is flat. In other instances, both the first and second frame components <NUM>, <NUM> may be flared. In addition, one of the first and second frame components <NUM>, <NUM> may be convex while the other of the first and second frame components <NUM>, <NUM> is flat or concave or both the first and second frame components <NUM>, <NUM> may be convex. Further, one of the first and second frame components <NUM>, <NUM> may be concave while the other of the first and second frame components <NUM>, <NUM> is flat or convex or both the first and second frame components <NUM>, <NUM> may be concave. In addition, the first and second frame components <NUM>, <NUM> may be different sizes.

The first and second frame components <NUM>, <NUM> may include a sensor integrated into the respective frame component, for example, for continuous monitoring of various hemodynamic parameters such as pressure, among other parameters, within the patient's body. For example, an antenna or inductor may be wrapped around the perimeter of one of the first and second frame components <NUM>, <NUM> and the sensor may be attached to the inductor. The sensor may be configured to, for example, sense physiologic properties, such as temperature, electrical signals of the heart, blood chemistry, blood pH level, hemodynamics, biomarkers, sound, pressure, and electrolytes that may be important in diagnosing, monitoring, and/or treating heart disease, heart failure, and/or other cardiovascular disease states.

In certain instances, the conduit portion <NUM> may be sizeable after delivery. The membrane <NUM> may be selectively adjustable by a balloon applied within the conduit portion <NUM> to distend the membrane <NUM>. The device <NUM> can be any size suitable to fit the anatomy of the patient. In certain instances, a diameter of the conduit portion is from <NUM> to <NUM>. For example, the diameter of the conduit portion may be from <NUM> to <NUM>, or from <NUM> to <NUM> depending on the anatomy of the patient and/or the desired treatment location. The first and second frame components <NUM>, <NUM> generally have a larger diameter than that of the conduit portion <NUM>, for example, so that the frame components may anchor the conduit portion <NUM> of the device <NUM> within the septum.

The device <NUM> can be any shape suitable to fit the anatomy of the patient. For example, the first and second frame portions <NUM>, <NUM> may be any of a variety of suitable shapes for anchoring the device <NUM> within the patient's body. For example, the first and second frame portions <NUM>, <NUM> may be substantially circular, ovular, diamond-shaped, star-shaped, flower-shaped, or any other suitable shape as desired. In certain instances, for example, at least one of the first and second set of elongate elements <NUM>, <NUM> form a star shape. In certain instances, both the first and second set of elongate elements <NUM>, <NUM> form a star shape.

In certain instances, the first set of elongate elements <NUM> forms a plurality of first lobes <NUM> and the second set of elongate elements <NUM> forms a plurality of second lobes <NUM>. Each of the plurality of first and second lobes <NUM>, <NUM> may include, for example, from <NUM> to <NUM> lobes, from <NUM> to <NUM> lobes, or from <NUM> to <NUM> lobes as desired. In certain instances, the plurality of first lobes <NUM> may have more lobes than the plurality of second lobes <NUM>, while in other instances, the plurality of first lobes <NUM> may have the same number of lobes or less lobes than the plurality of second lobes <NUM>.

<FIG> shows an example of an implantable medical device <NUM> being activated by an energy source, for example an energization unit <NUM>, in accordance with an embodiment. The energization unit <NUM> functions in a way similar to the extracorporeal energization unit <NUM> in that the energization unit <NUM> can transmit energy to the implantable medical device via magnetic induction and this energy can be converted to electrical energy to electrolytically degrade an element of the implanted medical device. Alternately, the energization unit <NUM> can deliver energy via an ultrasonic energy source, a laser energy source, a radiofrequency (RF) energy source, and/or another type of suitable energy source, which applies an energy transfer <NUM> to form an aperture in a membrane coupled to a flange, for example a membrane <NUM> coupled to the first flange <NUM>. Unlike the extracorporeal energization unit <NUM>, the energization unit <NUM> is delivered to a location within the heart H (e.g., in the right atrium RA) that is proximate to the membrane <NUM>. In one embodiment, a membrane of the membrane <NUM> can be melted to form the aperture after exposing the membrane <NUM> to thermal or ultrasound energy, to produce a thermal activation mechanism. In some examples, the size of the aperture can be adjusted by varying the amount of thermal activation.

In some embodiments, the medical device <NUM> may include an additional, secondary membrane (not shown) coupled to the second flange <NUM>. In these embodiments, one or both of the membranes are selectively absorptive to ultrasound such that the membranes are configured to be thermally opened using an ultrasound source to adjust flow through the medical device <NUM>. In some embodiments, one or both of the membranes are selectively absorptive to RF energy such that the membranes are thermally opened using an RF ablation source to adjust flow through the medical device <NUM>. In some embodiments, the membrane is selectively absorptive to laser energy such that the membrane is configured to be thermally opened using a laser source. In some embodiments, the membrane or the elements (e.g., wires) holding the membrane in place are selectively and electrolytically degradable using electrical energy supplied by an induction or other energy source. In some embodiments, both membranes are actuatable utilizing similar methods. For example, the membranes can both be configured to open simultaneously in response to receiving energy from an external source, e.g. RF energy, laser energy, induction energy, or others.

In some embodiments, one or both of the membranes are under radial tension to assist with forming one or both of the apertures therethrough. For example, when the membrane(s) are stretched, even a small opening in the membrane(s) can be enlarged when the radial tension placed from the outer edge of the membrane(s) pull the membrane(s) away from the locations of the openings in a plurality of directions. In some embodiments, the membrane(s) exhibit residual stress profile to assist with forming the one or both of the apertures in the membrane(s). In some embodiments, the membrane(s) are selectively openable between a plurality of sizes for the one or both of the apertures to modify flow through the medical device <NUM>.

<FIG> shows an example of an implantable medical device <NUM> according to an embodiment. The implantable medical device <NUM> has two flanges <NUM> and <NUM> engaged with a surface of the organ wall <NUM> to secure the medical device <NUM> in place, where the flanges <NUM> and <NUM> are located on opposite sides of the organ wall <NUM>. In one example, the organ wall <NUM> is an atrial wall between a left atrium and a right atrium of a heart, such that the first flange <NUM> is located on a surface of the atrial wall <NUM> in the right atrium, and the second flange is located on a surface of the atrial wall <NUM> in the left atrium with a conduit <NUM> extending between the two flanges <NUM> and <NUM> such that the conduit <NUM> forms the lumen <NUM> fluidly connecting the two atria of the heart. In other examples, the medical device <NUM> is secured to a ventricular wall or other tissue of the body as desired.

In some examples, the conduit <NUM> includes a membrane <NUM> made of a polymer material as described above that is impermeable to blood under physiologic conditions such that the membrane <NUM> separates the lumen <NUM> into two sections: a first lumen section 216A and a second lumen section 216B. In some examples, the membrane <NUM> is positioned in the middle of the lumen <NUM>, though the membrane may be offset toward or located at either end of the lumen <NUM>. In some examples, the membrane <NUM> is positioned at any location in the lumen <NUM> such that the first lumen section 216A has a greater volume than the second lumen section 216B or vice versa.

The membrane <NUM> helps prevent fluid flow through the lumen <NUM> (e.g., between the first and second lumen sections 216A and 216B), and therefore between the two opposite sides of the organ wall <NUM>. In some examples, the membrane <NUM> can be selectively absorptive to ultrasound, RF energy, laser energy, or any suitable source of energy as previously described, in which case absorbing the energy causes the membrane <NUM> to degrade, melt, or open to allow fluid to flow between the first and second lumen sections 216A and 216B. In some examples, the amount of fluid flow can be adjusted by changing a degree of degradation or a size of the opening in the membrane <NUM>.

Additionally, the medical device <NUM> includes one or more (e.g., three) locations to place one or more sensors to perform physiological measurements within the body. The first location <NUM> and the third location <NUM> are essentially similar to those mentioned above with respect to the medical device <NUM>. The second location <NUM> can be inside the conduit <NUM> for the sensor (e.g. a flow sensor) to measure the flow of fluid within the lumen <NUM>. In some examples, the second location <NUM> can be located in the first lumen section 216A or the second lumen section 216B. In some examples, the second location <NUM> can be adjacent to or proximate to the membrane <NUM> such that the sensor would also be able to detect when the membrane <NUM> is opened or degraded to permit fluid flow through the lumen <NUM>.

Claim 1:
An implantable medical device <NUM>, comprising:
a fluid shunt <NUM> adapted to extend through a wall <NUM> separating a first cavity <NUM> and a second cavity <NUM> within the heart,
the fluid shunt <NUM> including a first portion <NUM> adapted to extend into the first cavity <NUM> within the heart, a second portion <NUM> adapted to extend into the second cavity <NUM> within the heart, and an intermediate portion <NUM> interconnecting the first <NUM> and second portions <NUM>, the fluid shunt <NUM> having a lumen <NUM> extending between the first <NUM> and second <NUM> portions that is adapted to fluidly couple the first <NUM> and second <NUM> cavities within the heart;
an occlusion assembly <NUM> associated with the fluid shunt <NUM> and adapted to selectively occlude flow through the lumen <NUM> of the fluid shunt <NUM>, the occlusion assembly <NUM> being configured to be in a closed configuration such that the lumen of the fluid shunt is initially in a sealed state and to be activated to adjust flow through the lumen <NUM> of the fluid shunt <NUM>; wherein the occlusion assembly <NUM> comprises a thermoplastic polymer membrane; and
wherein the occlusion assembly <NUM> includes a thermal actuation mechanism configured to be activated by heating to adjust flow through the lumen <NUM> of the fluid shunt <NUM>; and
at least one sensor assembly associated with the first portion <NUM> of the fluid shunt <NUM> such that the at least one sensor assembly is adapted to sense one or more physiologic parameters in the first cavity <NUM>.