Patent Publication Number: US-2022233084-A1

Title: Blood-vessel-anchored cardiac sensor

Description:
RELATED APPLICATION 
     This application is a continuation application of PCI International Patent Application Serial No. PCT/US2020/0415975, filed Aug. 12, 2020 and entitled BLOOD-VESSEL-ANCHORED CARDIAC SENSOR, which claims priority based on United States Provisional Patent Application Ser. No. 62/890,537, filed on Aug. 22, 2019 and entitled PULMONARY-VEIN-ANCHORED CARDIAC SENSOR, the complete disclosures of both of which are hereby incorporated by reference herein in their entireties. 
    
    
     BACKGROUND 
     Field 
     The present disclosure generally relates to the field of medical devices and procedures. 
     Description of Related Art 
     Certain physiological parameters associated with chambers of the heart, such as fluid pressure and blood flow, can have an impact on patient health prospects. In particular, high cardiac fluid pressure can lead to heart failure, embolism formation, and/or other complications in some patients. Therefore, information relating to physiological conditions, such as pressure, in one or more chambers of the heart can be beneficial. 
     SUMMARY 
     Described herein are one or more methods and/or devices to facilitate monitoring of physiological parameter(s) associated with the left atrium using one or more sensor implant devices implanted in or to one or more pulmonary veins and/or associated anatomy/tissue. 
     In some implementations, the present disclosure relates to a method of sensing a physiological parameter. The method comprises advancing a delivery catheter to a right atrium of a heart of a patient via a transcatheter access path, advancing the delivery catheter through an interatrial septum wall into a left atrium of the heart, deploying a distal anchor of a sensor implant device from the delivery catheter, anchoring the distal anchor of the sensor implant device to a first pulmonary vein, withdrawing the delivery catheter away from the first pulmonary vein, thereby exposing at least a portion of a sensor module of the sensor implant device in the left atrium, deploying a proximal anchor of the sensor implant device from the delivery system, anchoring the proximal anchor of the sensor implant device to a second pulmonary vein, and withdrawing the delivery catheter from the heart. 
     The method may further comprise sensing a physiological parameter associated with the left atrium using a sensor element of the sensor module. For example, the physiological parameter can be left atrial blood pressure. 
     In some embodiments, the sensor implant device comprises a first arm portion that physically couples the sensor module to the distal anchor and a second arm portion that physically couples the sensor module to the proximal anchor. For example, the first and second arm portions may be part of a unitary arm structure coupled between the distal anchor device and the proximal anchor device. 
     In some embodiments, the sensor module includes an arm engagement feature configured to attach the sensor module to the arm structure. 
     In some embodiments, the sensor module includes a guide wire lumen configured to have a guide wire disposed therein. For example, the method may further comprise advancing the delivery catheter along a pre-positioned guide wire. 
     In some embodiments, the sensor module comprises a housing and a sensor element disposed at least partially within the housing. For example, the sensor element may be disposed at least partially within the housing such that a transducer surface of the sensor element is at least partially exposed to blood in the left atrium when the sensor implant device is disposed within the left atrium. 
     In some embodiments, the transducer surface is a pressure transducer diaphragm. 
     In some implementations, anchoring the distal anchor of the sensor implant device to the first pulmonary vein involves expanding a stent anchor within a conduit of the first pulmonary vein. 
     In some implementations, the present disclosure relates to a sensor implant device comprising a sensor module including a housing and a sensor element, a first stent anchor coupled to the sensor module via a first arm structure portion, and a second stent anchor coupled to the sensor module via a second arm structure portion. 
     Each of the first and second stent anchors may be self-expanding. 
     In some embodiments, the sensor element is configured to generate a signal indicative of a physiological parameter. For example, the physiological parameter can be fluid pressure. 
     The first and second arm structure portions can be part of a unitary bridge structure coupled between the first stent anchor and the second stent anchor. For example, the sensor module can include an engagement feature configured to engage with the bridge structure. 
     In some embodiments, the engagement feature is associated with an underside of a housing of the sensor module. 
     The sensor module can include a channel feature configured to receive therein a guide wire. 
     In some embodiments, the sensor element comprises a transducer surface that is at least partially exposed external to the housing. For example, the transducer surface can be associated with a pressure transducer diaphragm. 
     In some implementations, the present disclosure relates to a delivery system comprising an outer shaft, a sensor implant device disposed at least partially within the outer shaft. 
     The sensor implant device comprises a first anchor device, a second stent anchor device, and a sensor module physically coupled to the first anchor device and the second anchor device. 
     The delivery system further comprises a distal inner shaft disposed at least partially within the outer shaft and configured to axially abut the first anchor device within the outer shaft. 
     In some embodiments, the first anchor device is disposed without the distal inner shaft and distal to the inner shaft and the sensor module is disposed at least partially within the distal inner shaft. 
     The delivery system can further comprise a proximal inner shaft disposed at least partially within the distal inner shaft and configured to axially abut the sensor module within the distal inner shaft. For example, in some implementations, the second anchor device is disposed at least partially within the proximal inner shaft, the proximal inner shaft has a diameter that is less than a diameter of the distal inner shaft, the second anchor is disposed within the proximal inner shaft in an at least partially compressed configuration, and the second anchor in the at least partially compressed configuration has a diameter that is less than a diameter of the first anchor as configured and disposed within the outer shaft. 
     The second anchor can be coupled to the sensor module via an arm portion that is bent such that an end portion of the second anchor is distally oriented within the proximal inner shaft. 
     The delivery system can further comprise a pusher device disposed at least partially within the proximal inner shaft and configured to axially abut the second anchor device within the proximal inner shaft. For example, the pusher device can include a central lumen configured to receive a guidewire therein. 
     In some implementations, the present disclosure relates to a sensor implant device comprising a stent anchor, a first arm structure connected to the stent anchor and extending axially beyond an axial end of the stent anchor, and a sensor device secured to the first arm structure. 
     The stent anchor may be dimensioned to anchor within any of a pulmonary vein, a coronary sinus, and/or at least one of a superior vena cava or an inferior vena cava in an expanded deployment configuration. 
     The first arm structure may have a shape memory characteristics that cause the first arm structure to deflect radially outward with respect to an axis of the stent anchor when the sensor implant device is deployed. 
     The sensor implant device may further comprise a second arm structure connected to the stent anchor and secured to the sensor device. For example, the first arm structure and the second arm structure may be connected to opposite circumferential portions of the stent anchor, and/or the first arm structure and the second arm structure may be configured to hold the sensor device over a central axis of the stent anchor. 
     In some implementations, the present disclosure relates to a sensor implant device comprising a stent anchor and a sensor device secured to an inner diameter of the stent anchor. 
     In some embodiments, the sensor device comprises a housing that is configured to be engaged with one or more cells of a lattice structure of the stent anchor. 
     The sensor device can be secured to the stent anchor at an axial end of the stent anchor. 
     In some implementations, the present disclosure relates to a method of implanting a sensor implant device. The method comprises advancing a delivery system into to a first vena cava of a patient via a transcatheter access path, advancing the delivery system through at least a portion of a right atrium of the patient and into a second vena cava of the patient, deploying a distal anchor of a sensor implant device from the delivery system, anchoring the distal anchor of the sensor implant device within the second vena cava, withdrawing the delivery system through the at least a portion of the right atrium, thereby exposing at least a portion of a sensor device of the sensor implant device and a first support arm portion coupling the sensor device to the distal anchor in the right atrium, deploying a proximal anchor of the sensor implant device from the delivery system within the first vena cava, anchoring the proximal anchor of the sensor implant device to within the first vena cava, and withdrawing the delivery system from the patient. 
     The sensor device can be coupled to the proximal anchor via a second support arm portion. 
     For purposes of summarizing the disclosure, certain aspects, advantages and novel features have been described. It is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment. Thus, the disclosed embodiments may be carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various embodiments are depicted in the accompanying drawings for illustrative purposes and should in no way be interpreted as limiting the scope of the inventions. In addition, various features of different disclosed embodiments can be combined to form additional embodiments, which are part of this disclosure. Throughout the drawings, reference numbers may be reused to indicate correspondence between reference elements. 
         FIG. 1  shows a cross-sectional view of an example human heart. 
         FIG. 2  shows a top-down atrial cross-sectional view of a human heart. 
         FIG. 3  illustrates example pressure waveforms associated with various chambers and vessels of the heart according to one or more embodiments. 
         FIG. 4  illustrates a graph showing left atrial pressure ranges. 
         FIG. 5  shows a system for monitoring pressure and/or volume according to one or more embodiments. 
         FIG. 6  illustrates a heart having a sensor implant device implanted therein in accordance with one or more embodiments. 
         FIG. 7  shows a side view of a sensor implant device in accordance with one or more embodiments. 
         FIG. 8  shows a sensor implant device including anchor features engaged in a plurality of pulmonary veins in accordance with one or more embodiments. 
         FIGS. 9A and 9B  show front and side views, respectively, of a sensor implant device in an expanded configuration in accordance with one or more embodiments. 
         FIGS. 10A and 10B  show front and side views, respectively, of a sensor implant device in a compressed configuration in accordance with one or more embodiments. 
         FIG. 11  shows a cross-sectional view of a delivery system for a sensor implant device in accordance with one or more embodiments. 
         FIGS. 12-1, 12-2, 12-3, and 12-4  show a flow diagram illustrating a process for implanting a sensor implant device in accordance with one or more embodiments. 
         FIGS. 13-1, 13-2, 13-3, and 13-4  provide cross-sectional images of cardiac anatomy and certain devices/systems corresponding to operations of the process of  FIGS. 12-1, 12-2, 12-3, and 12-4  according to one or more embodiments. 
         FIGS. 14-1, 14-2, 14-3, and 14-4  provide side views of a sensor implant device in various configurations corresponding to the operations of the process of  FIGS. 12-1, 12-2, 12-3, and 12-4  according to one or more embodiments. 
         FIG. 15  shows a sensor implant device anchored in/to a left inferior pulmonary vein and a right superior pulmonary vein in accordance with one or more embodiments. 
         FIG. 16  shows a sensor implant device anchored in/to a left inferior pulmonary vein and a right inferior pulmonary vein in accordance with one or more embodiments. 
         FIG. 17  shows a sensor implant device anchored in/to a left superior pulmonary vein and a right inferior pulmonary vein in accordance with one or more embodiments. 
         FIG. 18  shows a sensor implant device anchored in/to a right inferior pulmonary vein and a right superior pulmonary vein in accordance with one or more embodiments. 
         FIG. 19A  shows a side deployed view of a sensor implant device anchored in a blood vessel in accordance with one or more embodiments. 
         FIG. 19B  shows an axial view of the sensor implant device of  FIG. 19A  in accordance with one or more embodiments. 
         FIG. 19C  shows a side view of the sensor implant device of  FIG. 19A  in a delivery configuration in accordance with one or more embodiments. 
         FIG. 20A  shows a side deployed view of a sensor implant device anchored in a blood vessel in accordance with one or more embodiments. 
         FIG. 20B  shows an axial view of the sensor implant device of  FIG. 20A  in accordance with one or more embodiments. 
         FIG. 20C  shows a side view of the sensor implant device of  FIG. 20A  in a delivery configuration in accordance with one or more embodiments. 
         FIG. 21A  shows a side deployed view of a sensor implant device anchored in a blood vessel in accordance with one or more embodiments. 
         FIG. 21B  shows an axial view of the sensor implant device of  FIG. 21A  in accordance with one or more embodiments. 
         FIG. 21C  shows a side view of the sensor implant device of  FIG. 21A  in a delivery configuration in accordance with one or more embodiments. 
         FIG. 22A  shows a side deployed view of a sensor implant device anchored in a blood vessel in accordance with one or more embodiments. 
         FIG. 22B  shows an axial view of the sensor implant device of  FIG. 22A  in accordance with one or more embodiments. 
         FIG. 22C  shows a side view of the sensor implant device of  FIG. 22A  in a delivery configuration in accordance with one or more embodiments. 
         FIG. 23  shows a sensor implant device implanted in the superior and inferior vena cavae in accordance with one or more embodiments. 
         FIGS. 24A-C  show crimped side, expanded front, and axial views, respectively, of a sensor implant device in accordance with one or more embodiments. 
         FIG. 25  shows a sensor implant device anchored in a superior vena cava in accordance with one or more embodiments. 
         FIG. 26  shows a sensor implant device anchored in an inferior vena cava in accordance with one or more embodiments. 
         FIG. 27  shows a sensor implant device anchored in a superior vena cava in accordance with one or more embodiments. 
         FIG. 28  shows a sensor implant device anchored in an inferior vena cava in accordance with one or more embodiments. 
         FIG. 29  shows a sensor implant device anchored in a coronary sinus in accordance with one or more embodiments. 
         FIG. 30  shows a sensor implant device anchored in a coronary sinus in accordance with one or more embodiments. 
         FIG. 31  shows a, sensor implant device anchored in a coronary sinus in accordance with one or more embodiments. 
         FIG. 32  illustrates various access paths through which access to a target cardiac anatomy may be achieved in accordance with one or more embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     The headings provided herein are for convenience only and do not necessarily affect the scope or meaning of the claimed inventive subject matter. The present disclosure relates to systems, devices, and methods for implanting and utilizing sensor implant devices configured to be implanted in the heart, such as at least partially within the left atrium and/or anchored to one or more pulmonary veins in fluid communication therewith. 
     Although certain preferred embodiments and examples are disclosed below, inventive subject matter extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses, and to modifications and equivalents thereof. Thus, the scope of the claims that may arise herefrom is not limited by any of the particular embodiments described below. For example, in any method or process disclosed herein, the acts or operations of the method or process may be performed in any suitable sequence and are not necessarily limited to any particular disclosed sequence. Various operations may be described as multiple discrete operations in turn, in a manner that may be helpful in understanding certain embodiments; however, the order of description should not be construed to imply that these operations are order dependent. Additionally, the structures, systems, and/or devices described herein may be embodied as integrated components or as separate components. For purposes of comparing various embodiments, certain aspects and advantages of these embodiments are described. Not necessarily all such aspects or advantages are achieved by any particular embodiment. Thus, for example, various embodiments may be carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other aspects or advantages as may also be taught or suggested herein. 
     The following includes a general description of human cardiac anatomy that is relevant to certain inventive features and embodiments disclosed herein and is included to provide context for certain aspects of the present disclosure. In humans and other vertebrate animals, the heart generally comprises a muscular organ having four pumping chambers, wherein the flow of blood between the pumping chambers is at least partially controlled by various heart valves, namely, the aortic, mitral (or bicuspid), tricuspid, and pulmonary valves. The valves may be configured to open and close in response to a pressure gradient present during various stages of the cardiac cycle (e.g., relaxation and contraction) to at least partially control the flow of blood to a respective region of the heart and/or to associated blood vessels (e.g., pulmonary, aorta, etc.). 
       FIGS. 1 and 2  illustrate vertical and horizontal cross-sectional views, respectively, of an example heart  1  having various features/anatomy relevant to certain aspects of the present inventive disclosure. The heart  1  includes four chambers, namely the left ventricle  3 , the left atrium  2 , the right ventricle  4 , and the right atrium  5 . A wall of muscle, referred to as the septum, separates the left-side chambers from the right-side chambers. In particular, an atrial septum wall portion  18  (referred to herein as the “atrial septum,” “interatrial septum,” or “septum”) separates the left atrium  2  from the right atrium  5 , whereas a ventricular septum wall portion  17  (referred to herein as the “ventricular septum,” “interventricular septum,” or “septum”) separates the left ventricle  3  from the right ventricle  4 . The inferior tip  19  of the heart  1  is referred to as the apex and is generally located on the midclavicular line, in the fifth intercostal space. The apex can be considered part of the greater apical region  39  identified in the drawings. 
     The left ventricle  3  is the primary pumping chamber of the heart  1 . A healthy left ventricle is generally conical or apical in shape, in that it is longer (along a longitudinal axis extending in a direction from the aortic valve  7  (not shown in  FIG. 1 ) to the apex) than it is wide (along a transverse axis extending between opposing walls  28 ,  29  at the widest point of the left ventricle) and descends from a base  15  with a decreasing cross-sectional diameter and/or circumference to the point or apex. Generally, the apical region  39  of the heart is a bottom region of the heart that is within the left and/or right ventricular region(s) but is distal to the mitral  6  and tricuspid  8  valves and disposed toward the tip  19  of the heart. 
     The pumping of blood from the left ventricle  3  is accomplished by a squeezing motion and a twisting or torsional motion. The squeezing motion occurs between the lateral wall  14  of the left ventricle  3  and the septum  17 . The twisting motion is a result of heart muscle fibers that extend in a circular or spiral direction around the heart. When these fibers contract, they produce a gradient of angular displacements of the myocardium from the apex to the base  15  about the longitudinal axis of the heart. The resultant force vectors extend at angles from about 30-60 degrees to the flow of blood through the aortic valve  7 . The contraction of the heart is manifested as a counterclockwise rotation of the apex relative to the base  15  when viewed from the apex. The contractions of the heart, in connection with the filling volumes of the left atrium  2  and ventricle  3 , respectively, can result in relatively high fluid pressures in the left side of the heart at least during certain phase(s) of the cardiac cycle, the results of which are discussed in detail below. 
     The four valves of the heart aid the circulation of blood in the heart. The tricuspid valve  8  separates the right atrium  5  from the right ventricle  4 . The tricuspid valve  8  generally has three cusps or leaflets and advantageously closes during ventricular contraction (i.e., systole) and opens during ventricular expansion (i.e., diastole), The pulmonary valve  9  separates the right ventricle  4  from the pulmonary artery  11  and generally is configured to open during systole so that blood may be pumped toward the lungs from the right ventricle  4 , and close during diastole to prevent blood from leaking back into the right ventricle  4  from the pulmonary artery. The pulmonary valve  9  generally has three cusps/leaflets. The mitral valve  6  generally has two cusps/leaflets and separates the left atrium  2  from the left ventricle  3 . The mitral valve  6  may generally be configured to open during diastole so that blood in the left atrium  2  can flow into the left ventricle  3 , and close during diastole to prevent blood from leaking back into the left atrium  2 . The aortic valve  7  separates the left ventricle  3  from the aorta  12 . The aortic valve  7  is configured to open during systole to allow blood leaving the left ventricle  3  to enter the aorta  12 , and close during diastole to prevent blood from leaking back into the left ventricle  3 . 
     The atrioventricular (i.e., mitral and tricuspid) heart valves are generally associated with a sub-valvular apparatus (not shown), including a collection of chordae tendineae and papillary muscles securing the leaflets of the respective valves to promote and/or facilitate proper coaptation of the valve leaflets and prevent prolapse thereof. The papillary muscles, for example, may generally comprise finger-like projections from the ventricle wall. Surrounding the ventricles ( 3 ,  4 ) are a number of arteries  22  that supply oxygenated blood to the heart muscle and a number of veins  28  that return the blood from the heart muscle to the right atrium  5  via the coronary sinus  16  (see  FIG. 2 ). The coronary sinus  16  is a relatively large vein that extends generally around the upper portion of the left ventricle  3  and provides a return conduit for blood returning to the right atrium  5 . The coronary sinus  16  terminates at the coronary ostium  14 , through which the blood enters the right atrium. 
     The primary roles of the left atrium  2  are to act as a holding chamber for blood returning from the lungs (not shown) and to act as a pump to transport blood to other areas of the heart. The left atrium  2  receives oxygenated blood from the lungs via the pulmonary veins  23 ,  26 . The oxygenated blood that is collected from the pulmonary veins  23 ,  26  in the left atrium  2  enters the left ventricle  3  through the mitral valve  6 . In some patients, the walls of the left atrium  2  are slightly thicker than the walls of the right atrium  5 . Deoxygenated blood enters the right atrium  5  through the inferior  29  and superior  19  venae cavae. The right side of the heart then pumps this deoxygenated blood into the pulmonary arteries around the lungs. There, fresh oxygen enters the blood stream, and the blood moves to the left side of the heart via a network of pulmonary veins ultimately terminating at the left atrium  2 , as shown. 
     The ostia  23 ,  26  of the pulmonary veins are generally located at or near posterior left atrial wall of the left atrium  2 . The right pulmonary veins  21 ,  23  carry blood from the right lung to the left atrium, where it is distributed to the rest of the circulatory system as described in detail herein. The right pulmonary veins include the right inferior pulmonary vein  21  and the right superior pulmonary vein  23 , as shown. Meanwhile, the left pulmonary veins  25 ,  27  generally include the left inferior pulmonary vein  25  and the left superior pulmonary vein  27 . The left pulmonary veins generally carry blood from the left lung into the left atrium  2 , where it continues to flow to the rest the body, 
     Heart Failure 
     As referenced above, certain physiological conditions or parameters associated with the cardiac anatomy can impact the health of a patient. For example, congestive heart failure is a condition associated with the relatively slow movement of blood through the heart and/or body, which causes the fluid pressure in one or more chambers of the heart to increase. As a result, the heart does not pump sufficient oxygen to meet the body&#39;s needs. The various chambers of the heart may respond to pressure increases by stretching to hold more blood to pump through the body or by becoming relatively stiff and/or thickened. The walls of the heart can eventually weaken and become unable to pump as efficiently. In some cases, the kidneys may respond to cardiac inefficiency by causing the body to retain fluid. Fluid buildup in arms, legs, ankles, feet, lungs, and/or other organs can cause the body to become congested, which is referred to as congestive heart failure. Acute decompensated congestive heart failure is a leading cause of morbidity and mortality, and therefore treatment and/or prevention of congestive heart failure is a significant concern in medical care. 
     The treatment and/or prevention of heart failure (e.g., congestive heart failure) can advantageously involve the monitoring of pressure in one or more chambers or regions of the heart or other anatomy, such as monitoring of left atrial pressure. As described above, pressure buildup in one or more chambers or areas of the heart can be associated with congestive heart failure. However, without direct or indirect monitorings of cardiac pressure (e.g., left atrial pressure, it can be difficult to infer, determine, or predict the presence or occurrence of congestive heart failure. For example, treatments or approaches not involving direct or indirect pressure monitoring may involve measuring or observing other present physiological conditions of the patient, such as measuring body weight, thoracic impedance, right heart catheterization, or the like. 
     In some solutions, pulmonary capillary wedge pressure can be measured as a surrogate of left atrial pressure. For example, a pressure sensor may be disposed or implanted in the pulmonary artery, and readings associated therewith may be used as a surrogate for left atrial pressure. However, with respect to catheter-based pressure measurement in the pulmonary artery or certain other chambers or regions of the heart, use of invasive catheters may be required to maintain such pressure sensors, which may be uncomfortable or difficult to implement. Furthermore, certain lung-related conditions may affect pressure readings in the pulmonary artery, such that the correlation between pulmonary artery pressure and left atrial pressure may be undesirably attenuated. As an alternative to pulmonary artery pressure measurement, pressure measurements in the right ventricle outflow tract may relate to left atrial pressure as well. However, the correlation between such pressure readings and left atrial pressure may not be sufficiently strong to be utilized in congestive heart failure diagnostics, prevention, and/or treatment. 
     Additional solutions may be implemented for deriving or inferring left atrial pressure. For example, the E/A ratio, which is a marker of the function of the left ventricle of the heart representing the ratio of peak velocity blood flow from gravity in early diastole (the E wave) to peak velocity flow in late diastole caused by atrial contraction (the A wave), can be used as a surrogate for measuring left atrial pressure. The E/A ratio may be determined using echocardiography or other imaging technology; generally, abnormalities in the DA ratio may suggest that the left ventricle cannot fill with blood properly in the period between contractions, which may lead to symptoms of heart failure, as explained above. However, E/A ratio determination generally does not provide absolute pressure measurement values. 
     Various methods for identifying and/or treating congestive heart failure involve the observation of worsening congestive heart failure symptoms and/or changes in body weight. However, such signs may appear relatively late and/or be relatively unreliable. For example, daily bodyweight measurements may vary significantly (e.g., up to 9% or more) and may be unreliable in signaling heart-related complications. Furthermore, treatments guided by monitoring signs, symptoms, weight, and/or other biomarkers have not been shown to substantially improve clinical outcomes. In addition, for patients that have been discharged, such treatments may necessitate remote telemedicine systems. 
     The present disclosure provides systems, devices, and methods for guiding the administration of medication relating to the treatment of congestive heart failure at least in part by directly monitoring pressure in the left atrium, or other chamber or vessel for which pressure measurements are indicative of left atrial pressure, in order to reduce hospital readmissions, morbidity, and/or otherwise improve the health prospects of patient at risk of heart failure. 
     Cardiac Pressure Monitoring 
     Cardiac pressure monitoring in accordance with embodiments of the present disclosure may provide a proactive intervention mechanism for preventing or treating congestive heart failure. Generally, increases in ventricular filling pressures associated with diastolic and/or systolic heart failure can occur prior to the occurrence of symptoms that lead to hospitalization. For example, cardiac pressure indicators may present weeks prior to hospitalization for some patients. Therefore, pressure monitoring systems in accordance with embodiments of the present disclosure may advantageously be implemented to reduce instances of hospitalization by guiding the appropriate or desired titration and/or administration of medications before the onset of heart failure. 
     Dyspnea represents a cardiac pressure indicator characterized by shortness of breath or the feeling that one cannot breathe well enough. Dyspnea may result from elevated atrial pressure, which may cause fluid buildup in the lungs from pressure back-up. Pathological dyspnea can result from congestive heart failure. However, a significant amount of time may elapse between the time of initial pressure elevation and the onset of dyspnea, and therefore symptoms of dyspnea may not provide sufficiently-early signaling of elevated atrial pressure. By monitoring pressure directly according to embodiments of the present disclosure, normal ventricular filling pressures may advantageously be maintained, thereby preventing or reducing effects of heart failure, such as dyspnea. 
     As referenced above, with respect to cardiac pressures, pressure elevation in the left atrium may be particularly correlated with heart failure.  FIG. 3  illustrates example pressure waveforms associated with various chambers and vessels of the heart according to one or more embodiments. The various waveforms illustrated in  FIG. 3  may represent waveforms obtained using right heart catheterization to advance one or more pressure sensors to the respective illustrated and labeled chambers or vessels of the heart. As illustrated in  FIG. 3 , the waveform  325 , which represents left atrial pressure, may be considered to provide the best feedback for early detection of congestive heart failure. Furthermore, there may generally be a relatively strong correlation between increases and left atrial pressure and pulmonary congestion. 
     Left atrial pressure may generally correlate well with left ventricular end-diastolic pressure. However, although left atrial pressure and end-diastolic pulmonary artery pressure can have a significant correlation, such correlation may be weakened when the pulmonary vascular resistance becomes elevated. That is, pulmonary artery pressure generally fails to correlate adequately with left ventricular end-diastolic pressure in the presence of a variety of acute conditions, which may include certain patients with congestive heart failure. For example, pulmonary hypertension, which affects approximately 35-83% of patients with heart failure, can affect the reliability of pulmonary artery pressure measurement for estimating left-sided filling pressure. Therefore, pulmonary artery pressure measurement alone, as represented by the waveform  326 , may be an insufficient or inaccurate indicator of left ventricular end-diastolic pressure, particularly for patients with co-morbidities, such as lung disease and/or thromboembolism. Left atrial pressure may further be correlated at least partially with the presence and/or degree of mitral regurgitation. 
     Left atrial pressure readings may be relatively less likely to be distorted or affected by other conditions, such as respiratory conditions or the like, compared to the other pressure waveforms shown in  FIG. 3 . Generally, left atrial pressure may be significantly predictive of heart failure, such as up two weeks before manifestation of heart failure. For example, increases in left atrial pressure, and both diastolic and systolic heart failure, may occur weeks prior to hospitalization, and therefore knowledge of such increases may be used to predict the onset of congestive heart failure. 
     Cardiac pressure monitoring, such as left atrial pressure monitoring, can provide a mechanism to guide administration of medication to treat and/or prevent congestive heart failure. Such treatments may advantageously reduce hospital readmissions and morbidity, as well as provide other benefits. An implanted pressure sensor in accordance with embodiments of the present disclosure may be used to predict heart failure up two weeks or more before the manifestation of symptoms or markers of heart failure (e.g., dyspnea). When heart failure predictors are recognized using cardiac pressure sensor embodiments in accordance with the present disclosure, certain prophylactic measures may be implemented, including medication intervention, such as modification to a patient&#39;s medication regimen, which may help prevent or reduce the effects of cardiac dysfunction. Direct pressure measurement in the left atrium can advantageously provide an accurate indicator of pressure buildup that may lead to heart failure or other complications. For example, trends of atrial pressure elevation may be analyzed or used to determine or predict the onset of cardiac dysfunction, wherein drug or other therapy may be augmented to cause reduction in pressure and prevent or reduce further complications. 
       FIG. 4  illustrates a graph  300  showing left atrial pressure ranges including a normal range  301  of left atrial pressure that is not generally associated with substantial risk of postoperative atrial fibrillation, acute kidney injury, myocardial injury, heart failure and/or other health conditions. Embodiments of the present disclosure provide systems, devices, and methods for determining whether a patient&#39;s left atrial pressure is within the normal range  301 , above the normal range  303 , or below the normal range  302 . For detected left atrial pressure above the normal range, which may be correlated with an increased risk of heart failure, embodiments of the present disclosure as described in detail below can inform efforts to reduce the left atrial pressure until it is brought within the normal range  301 . Furthermore, for detected left atrial pressure that is below the normal range  301 , which may be correlated with increased risks of acute kidney injury, myocardial injury, and/or other health complications, embodiments of the present disclosure as described in detail below can serve to facilitate efforts to increase the left atrial pressure to bring the pressure level within the normal range  301 . 
     Cardiac Implant Sensor System 
     Embodiments of the present disclosure provide systems, devices, and methods for determining and/or monitoring fluid pressure and/or other physiological parameters or conditions in the left atrium using one or more implantable sensor devices, such as permanently implanted sensor devices. By placing a permanent sensor monitor device directly in the left atrium, embodiments of the present disclosure can advantageously allow physicians and/or technicians to gather real-time cardiac information, including left atrial pressure values and/or other valuable cardiac parameters. 
     Disclosed solutions for monitoring and/or controlling cardiac pressure and/or compliance in the atrial chamber(s) for the purpose of reducing the risk of heart failure and/or other health complications may be implemented in connection with a pressure-monitoring system.  FIG. 5  illustrates a system  500  for monitoring pressure and/or other parameter(s) in accordance with embodiments of the present disclosure. Although the description of  FIG. 5  and other embodiments herein is generally presented in the context of pressure monitoring, it should be understood that description of pressure monitoring herein is applicable to monitoring of other physiological parameters. 
       FIG. 5  shows a system  500  for monitoring pressure (e.g., left atrial pressure) in a patient  515  according to one or more embodiments. The patient  515  can have a pressure sensor implant device  510  implanted in, for example, the heart (not shown), or associated physiology, of the patient. For example, the sensor implant device  510  can be implanted at least partially within the left atrium of the patient&#39;s heart. The sensor implant device  510  can include one or more sensor transducers  512 , such as one or more microelectromechanical system (MEMS) devices, such as MEMS pressure sensors, or the like. 
     In certain embodiments, the monitoring system  500  can comprise at least two subsystems, including an implantable internal subsystem or device  510  that includes the sensor transducer(s)  512  (e.g., MEMS pressure sensor(s)), as well as control circuitry  514  comprising one or more microcontroller(s), discrete electronic component(s), and one or more power and/or data transmitter(s)  518  (e.g., antennae coil). The monitoring system  500  can further include an external (e.g., non-implantable) subsystem that includes an external reader  550  (e.g., coil), which may include a wireless transceiver that is electrically and/or communicatively coupled to certain control circuitry. In certain embodiments, both the internal and external subsystems include a corresponding antenna for wireless communication and/or power delivery through patient tissue disposed therebetween. The sensor implant device  510  can be any type of implant device. 
     Certain details of the sensor implant device  510  are illustrated in the enlarged block  510  shown. The sensor implant device  510  can comprise anchor structure  520  as described herein. For example, the anchor structure  520  can include one or more stent-type anchors for anchoring in one or more pulmonary veins, as described in greater detail below. The anchor structure can further comprise one or more arm/bridge structures that physically couple the sensor housing  516  to one or more stents or other tissue and/or vessel anchors. Although certain components are illustrated in  FIG. 5  as part of the sensor implant device  510 , it should be understood that the sensor implant device  510  may only comprise a subset of the illustrated components/modules and can comprise additional components/modules not illustrated. The sensor implant device  510  includes one or more sensor transducers  512 , which can be configured to provide a response indicative of one or more physiological parameters of the patient  515 , such as atrial pressure and/or volume. Although pressure transducers are described, the sensor transducer(s)  512  can comprise any suitable or desirable types of sensor transducer(s) for providing signals relating to physiological parameters or conditions associated with the sensor implant device  510 . 
     The sensor transducer(s)  512  can comprise one or more MEMS sensors, optical sensors, piezoelectric sensors, electromagnetic sensors, strain sensors/gauges, accelerometers, gyroscopes, and/or other types of sensors, which can be positioned in the patient  515  to sense one or more parameters relevant to the health of the patient. The transducer  512  may be a force-collector-type pressure sensor. In some embodiments, the transducer  512  comprises a diaphragm, piston, Bourdon tube, bellows, or other strain- or deflection-measuring component(s) to measure strain or deflection applied over an area/surface thereof. The transducer  512  may be associated with a sensor housing  516 , such that at least a portion thereof is contained within, or attached to, the housing  516 . The term “associated with” is used herein according to its broad and ordinary meaning. With respect to sensor devices/components being “associated with” an anchor or other implant structure, such terminology may refer to a sensor device or component being physically coupled, attached, or connected to, or integrated with, the anchor or other implant structure. 
     In some embodiments, the transducer  512  comprises or is a component of a piezoresistive strain gauge, which may be configured to use a bonded or formed strain gauge to detect strain due to applied pressure, wherein resistance increases as pressure deforms the component/material. The transducer  512  may incorporate any type of material, including but not limited to silicon (e.g., monocrystalline), polysilicon thin film, bonded metal foil, thick film, silicon-on-sapphire, sputtered thin film, and/or the like. 
     In some embodiments, the transducer  512  comprises or is a component of a capacitive pressure sensor including a diaphragm and pressure cavity configured to form a variable capacitor to detect strain due to pressure applied to the diaphragm. The capacitance of the capacitive pressure sensor may generally decrease as pressure deforms the diaphragm. The diaphragm may comprise any material(s), including but not limited to metal, ceramic, silicon or other semiconductor, and the like. In some embodiments, the transducer  512  comprises or is a component of an electromagnetic pressure sensor, which may be configured to measures the displacement of a diaphragm by means of changes in inductance, linear variable displacement transducer (LVDT) functionality, Hall Effect, or eddy current sensing. In some embodiments, the transducer  512  comprises or is a component of a piezoelectric strain sensor. For example, such a sensor may determine strain (e.g., pressure) on a sensing mechanism based on the piezoelectric effect in certain materials, such as quartz. 
     In some embodiments, the transducer  512  comprises or is a component of a strain gauge. For example, a strain gauge embodiment may comprise a pressure sensitive element on or associated with an exposed surface of the transducer  512 . In some embodiments, a metal strain gauge is adhered to the sensor surface, or a thin-film gauge may be applied on the sensor by sputtering or other technique. The measuring element or mechanism may comprise a diaphragm or metal foil. The transducer  512  may comprise any other type of sensor or pressure sensor, such as optical, potentiometric, resonant, thermal, ionization, or other types of strain or pressure sensors. 
     In some embodiments, the transducer(s)  512  is/are electrically and/or communicatively coupled to the control circuitry  514 , which may comprise one or more application-specific integrated circuit (ASIC) microcontrollers or chips. The control circuitry  514  can further include one or more discrete electronic components, such as tuning capacitors or the like. 
     In certain embodiments, the sensor transducer(s)  512  can be configured to generate electrical signals that can be wirelessly transmitted to a device outside the patient&#39;s body, such as the illustrated local external monitor system  550 . In order to perform such wireless data transmission, the sensor implant device  510  can include radio frequency (RF) transmission circuitry, such as a signal processing circuitry and an antenna  518 . The antenna  518  can comprise an internal antenna coil or other structure implanted within the patient. The control circuitry  514  may comprise any type of transducer circuitry configured to transmit an electromagnetic signal, wherein the signal can be radiated by the antenna  518 , which may comprise one or more conductive wires, coils, plates, or the like. The control circuitry  514  of the sensor implant device  510  can comprise, for example, one or more chips or dies configured to perform some amount of processing on signals generated and/or transmitted using the device  510 . However, due to size, cost, and/or other constraints, the sensor implant device  510  may not include independent processing capability in some embodiments. 
     The wireless signals generated by the sensor implant device  510  can be received by the local external monitor device or subsystem  550 , which can include a transceiver module  553  configured to receive the wireless signal transmissions from the sensor implant device  510 , which is disposed at least partially within the patient  515 . The external local monitor  550  can receive the wireless signal transmissions and/or provide wireless power using an external antenna  555 , such as a wand device. The transceiver  553  can include radio-frequency (RF) front-end circuitry configured to receive and amplify the signals from the sensor implant device  510 , wherein such circuitry can include one or more filters (e.g., band-pass filters), amplifiers (e.g., low-noise amplifiers), analog-to-digital converters (ADC) and/or digital control interface circuitry, phase-locked loop (PLL) circuitry, signal mixers, or the like. The transceiver  553  can further be configured to transmit signals over a network  575  to a remote monitor subsystem or device  560 . The RF circuitry of the transceiver  553  can further include one or more of digital-to-analog converter (DAC) circuitry, power amplifiers, low-pass filters, antenna switch modules, antennas or the like for treatment/processing of transmitted signals over the network  575  and/or for receiving signals from the sensor implant device  510 . In certain embodiments, the local monitor  550  includes control circuitry  551  for performing processing of the signals received from the sensor implant device  510 . The local monitor  550  can be configured to communicate with the network  575  according to a known network protocol, such as Ethernet, Wi-Fi, or the like. In certain embodiments, the local monitor  550  is a smartphone, laptop computer, or other mobile computing device, or any other type of computing device. 
     In certain embodiments, the sensor implant device  510  includes some amount of volatile and/or non-volatile data storage. For example, such data storage can comprise solid-state memory utilizing an array of floating-gate transistors, or the like. The control circuitry  514  may utilize data storage for storing sensed data collected over a period of time, wherein the stored data can be transmitted periodically to the local monitor  550  or another external subsystem. In certain embodiments, the sensor implant device  510  does not include any data storage. The control circuitry  514  is configured to facilitate wireless transmission of data generated by the sensor transducer(s)  512 , or other data associated therewith. The control circuitry  514  may further be configured to receive input from one or more external subsystems, such as from the local monitor  550 , or from a remote monitor  560  over, for example, the network  575 . For example, the sensor implant device  510  may be configured to receive signals that at least partially control the operation of the sensor implant device  510 , such as by activating/deactivating one or more components or sensors, or otherwise affecting operation or performance of the sensor implant device  510 . 
     The one or more components of the sensor implant device  510  can be powered by one or more power sources  540 . Due to size, cost and/or electrical complexity concerns, it may be desirable for the power source  540  to be relatively minimalistic in nature. For example, high-power driving voltages and/or currents in the sensor implant device  510  may adversely affect or interfere with operation of the heart or other anatomy associated with the implant device. In certain embodiments, the power source  540  is at least partially passive in nature, such that power can be received from an external source wirelessly by passive circuitry of the sensor implant device  510 . Examples of wireless power transmission technologies that may be implemented include but are not limited to short-range or near-field wireless power transmission, or other electromagnetic coupling mechanism(s). For example, the local monitor  550  may serve as an initiator that actively generates an RF field that can provide power to the sensor implant device  510 , thereby allowing the power circuitry of the implant device to take a relatively simple form factor. In certain embodiments, the power source  540  can be configured to harvest energy from environmental sources, such as fluid flow, motion, pressure, or the like. Additionally or alternatively, the power source  540  can comprise a battery, which can advantageously be configured to provide enough power as needed over the relevant monitoring period. 
     In some embodiments, the local monitor device  550  can serve as an intermediate communication device between the sensor implant device  510  and the remote monitor  560 . The local monitor device  550  can be a dedicated external unit designed to communicate with the sensor implant device  510 . For example, the local monitor device  550  can be a wearable communication device, or other device that can be readily disposed in proximity to the patient  515  and/or sensor implant device  510 . The local monitor device  550  can be configured to continuously, periodically, or sporadically interrogate the sensor implant device  510  in order to extract or request sensor-based information therefrom. In certain embodiments, the local monitor  550  comprises a user interface, wherein a user can utilize the interface to view sensor data, request sensor data, or otherwise interact with the local monitor system.  550  and/or sensor implant device  510 . 
     The system  500  can include a secondary local monitor  570 , which can be, for example, a desktop computer or other computing device configured to provide a monitoring station or interface for viewing and/or interacting with the monitored cardiac data. In an embodiment, the local monitor  550  can be a wearable device or other device or system configured to be disposed in close physical proximity to the patient and/or sensor implant device  510 , wherein the local monitor  550  is primarily designed to receive/transmit signals to and/or from the sensor implant device  510  and provide such signals to the secondary local monitor  570  for viewing, processing, and/or manipulation thereof. The external local monitor system  550  can be configured to receive and/or process certain metadata from or associated with the sensor implant device  510 , such as device ID or the like, which can also be provided over the data coupling from the sensor implant device  510 . 
     The remote monitor subsystem  560  can be any type of computing device or collection of computing devices configured to receive, process and/or present monitor data received over the network  575  from the local monitor device  550 , secondary local monitor  570 , and/or sensor implant device  510 . For example, the remote monitor subsystem  560  can advantageously be operated and/or controlled by a healthcare entity—such as a hospital, doctor, or other care entity associated with the patient  515 . 
     In certain embodiments, the antenna  555  of the external monitor system  550  comprises an external coil antenna that is matched and/or tuned to be inductively paired with the antenna  518  of the internal implant  510 . In some embodiments, the sensor implant device  510  is configured to receive wireless ultrasound power charging and/or data communication between from the external monitor system  550 . As referenced above, the local external monitor  550  can comprise a wand or other hand-held reader. 
     In some embodiments, at least a portion of the transducer  512 , control circuitry  514 , power source  540  and/or the antenna  518  is at least partially disposed or contained within the sensor housing  516 , which may comprise any type of material, and may advantageously be at least partially hermetically sealed. For example, the housing  516  may comprise glass or other rigid material in some embodiments, which may provide mechanical stability and/or protection for the components housed therein. In some embodiments, the housing  516  is at least partially flexible. For example, the housing may comprise polymer or other flexible structure/material, which may advantageously allow for folding, bending, or collapsing of the sensor  510  to allow for transportation thereof through a catheter or other percutaneous introducing means. 
     The sensor implant device  510  may be implanted in any location in the body the patient  515 . In some embodiments of the present disclosure, the sensor implant device  510  is advantageously implanted in the heart of the patient  515 , such as in or near the left atrium of the heart, as described in detail herein. Placement of the sensor implant device  510  at least partially within the left atrium can advantageously provide a desirable location for measuring and/or monitoring left atrial pressure, blood viscosity, temperature, and/or other cardiac crammer(s). Sensor implant devices in accordance with one or more embodiments of the present disclosure may be implanted using transcatheter procedures, or any other percutaneous procedures. Alternatively, sensor implant devices in accordance with aspects of the present disclosure may be placed during open-heart surgery (e.g., sternotomy), mini-sternotomy, and/or other surgical operation. 
     The various embodiments shown in the accompanying figures and described herein include various features. It should be understood that a given embodiment may not include all of the features illustrated or described in connection with the embodiment and may include one or more additional features shown or described in connection with one or more other embodiments. That is, the features of the illustrated and/or described embodiments of the present disclosure may be combined in any desired combination in an embodiment within the scope of the present disclosure. 
     In some of the figures accompanying the present disclosure, certain reference numbers may be re-used as a matter of convenience for devices and modules having features that are similar in one or more respects. However, re-use of common reference numbers in the drawings does not necessarily indicate that such features, devices, components, or modules are identical, 
     Sensor Implant Devices and Methods 
     The diagram of  FIG. 6  shows the sensor implant device  610  implanted at least partially within the left atrium  2 , such that a sensor component  616  thereof may advantageously be positioned and/or disposed to determine or acquire sensor signals indicative of one or more physiological parameters associated with the sensor device  610  and/or left atrium  2 . In some implementations, the sensor implant device  610  may advantageously be anchored to one or more anatomical features/locations associated with the left atrium  2 . For example, the sensor implant device  610  may comprise one or more anchors and/or other features configured to be anchored at, in, or near one or more of the left  26  and/or right  23  pulmonary veins. With the sensor component  616 , which may advantageously comprise or be associated with a sensor transducer/element  612 , at least partially exposed within the left atrium  2 , the sensor component  616  may be able to measure various cardiac parameter(s), including but not limited to left atrial pressure, blood viscosity, temperature, and/or others. 
     In some implementations, the sensor implant device  610  comprises a first anchor  622 , which may be a stent-type anchor configured to be expanded to provide a friction fit with in the ostium and/or vessel associated with a first pulmonary vein, as shown. The sensor implant device  610  can further comprise a second anchor  624 , which may be configured and/or designed to be implanted to/in an ostium or vessel associated with a second pulmonary vein, as shown. For example, the anchor  624  may comprise a stent-type anchor, or a barb-type or other type of anchor configured to be embedded at least partially within biological tissue at or near a target implantation location. 
     The sensor implant device  610  further comprises one or more arms or support structures, which may be used to position the sensor component  616  in a desired implant position and/or secure the sensor component  616  to one or more anchor features of the sensor implant device  610 . For example, as shown, the arm portion  633  can advantageously secure the sensor component  616  to the first anchor  622 , whereas the arm portion  631  may support or secure the sensor component  616  to the second anchor feature  624 . 
       FIG. 7  shows a sensor implant device  710  implanted in one or more vessels  701 ,  702  of patient anatomy, such as cardiac anatomy, as described in detail herein. The sensor implant device  710  advantageously comprises a sensor element, unit, and/or module  716 , which may have a sensor transducer element  712  associated therewith. For example, the sensor transducer element  712  may advantageously be disposed and/or attached at an outward-facing face or surface of the sensor module  716 , such that physiological parameters associated with the environment to which the outward-facing surface of the sensor module  716  is exposed can be determined and/or translated by the sensor transducer  712  to a form that can be interpreted and/or indicative of one or more physiological parameters associated with the implantation site of the sensor implant device  710 . The sensor module  716  may be anchored order implanted/secured in any suitable or desirable way or manner. For example, in some embodiments of the present disclosure, sensor elements are physically, and mechanically coupled to one or more anchor devices by one or more arm or bridge features  730 . For example, the illustrated implant device  710  includes a first arm member portion  731 , as well as a second arm or member portion  733 , each of which may be coupled to a respective anchor device, as shown. In some embodiments, the arm member portions  731 ,  733  are part of a single unitary form or structure. That is, the sensor module  716  may advantageously be mechanically or physically coupled to a bridge structure  730 , wherein portions of such bridge structure on respective sides of the sensor module  716  are called-out in  FIG. 7  as arm member portions  731 ,  733 , respectively. 
     The implant device  710 , as referenced above, may advantageously comprise one or more anchor devices configured to be anchored in or to a vessel or conduit, such as a blood vessel and/or associated ostium, or the like. Certain embodiments of the present disclosure are described in the context of stent-type anchor devices, which are illustrated as example conduit anchors in  FIG. 7  as well as other example Figures associated with the present disclosure. As described in detail herein, the sensor implant device  710  may be anchored to and/or within one or more pulmonary veins and/or other cardiac blood vessel(s) to advantageously secure the sensor module  716  in a position exposed at least partially within the left atrium and/or other chamber of the heart in some implementations. For example, the vessel  701  may represent a first pulmonary vein, whereas the vessel  702  may represent a second pulmonary vein. In some implementations, a first anchor device associated with a sensor implant device may be implanted or anchored to a pulmonary vein, whereas a second anchor device associated with the sensor implant device may be implanted or anchored in another manner/configuration, such as by embedding into tissue, or the like. 
     Although some embodiments disclosed herein describe stent-type anchor device(s), it should be understood that any types/configurations of anchor devices may be implemented in accordance with embodiments of the present disclosure. For example, in some embodiments, other expansive anchor forms or devices may be implemented, such as pre-shaped wireforms, struts, clips, and/or other anchor device(s). The use of stent-type anchors, as described in detail herein, can advantageously allow for blood flow to flow within the pulmonary vein(s) through the anchor(s) into the left atrium, such that the functionality/flow of the pulmonary vein(s) is not substantially impacted or obstructed. In some embodiments, opposing clips or arms configured to present outward and/or inward radial force with respect to one another may be utilized to secure a sensor implant device in accordance with embodiments of the present disclosure in a desired position/place. For example, the illustrated anchor devices  722 ,  724  may each provide outward radial force relative to a central axis of the respective anchor device to secure the respective implant device within the target vessel in which it is implanted. Furthermore, each of the arm portions  731 ,  733  may further be pre-shaped and/or otherwise configured to present an outward and/or inward radial force to further secure the implant device  710  in the desired position as secured to the vessel  701 ,  702 . 
     One or both of the anchor devices  722 ,  724  may advantageously be at least partially self-expanding, which may provide a relatively simple deployment process for deploying respective anchors. Additionally or alternatively, one or both of the anchor devices  722 ,  724  may be balloon-expandable and/or expandable using another means or mechanism. Although two anchor devices are shown in  FIG. 7  and in certain other Figures associated with the present disclosure, it should be understood that in some embodiments of the sensor implant device  710  is associated with one anchor device, or more than two anchor devices. For example, some important notations, the sensor implant device  710  has three or more anchor devices, each of which is associated with a separate arm/member portion secured indirectly or directly to the sensor module  716  in any suitable or desirable manner. 
       FIG. 8  shows a top-down view of a left atrium  2  having implanted therein a sensor implant device  810  in accordance with one or more embodiments of the present disclosure. The sensor implant device  810  shown in  FIG. 8  includes various features that may be incorporated in any of the disclosed embodiments. For example, the sensor implant device  810  can include a sensor component  816 , arm member(s)/structure(s)  830 , and/or anchors  822 ,  824 , as described in detail herein. 
     As described in detail herein, tissue-anchoring components or portions of a sensor implant device in accordance with embodiments of the present disclosure may comprise any suitable or desirable form or mechanism, including any known tissue-anchoring devices or mechanisms. In the illustrated embodiment of  FIG. 8 , the sensor implant device  810  advantageously includes expandable anchors  822 ,  824  associated with proximal and distal end portions of the sensor implant device  810 . One or both of the anchors  822 ,  824  may be tension-/resistance-type anchors, such as a stent or similar structure or device. For example, one or both of the anchors  822 ,  824  may be expanded within a respective pulmonary vein  825 ,  827 , as shown. 
     In implementations in which the sensor implant device  810  is anchored to more than one pulmonary vein, as in  FIG. 8 , the bridge/arm member(s)/structure(s)  830  may be configured to be span the distance between pulmonary veins (e.g., adjacent pulmonary veins  822 ,  824 ) and/or ostia thereof, as shown. The bridge/arm member(s)/structure(s)  830  may be configured to provide inward radial force with respect to the axis of one or both of the anchors  822 ,  824  to thereby provide additional anchoring of the sensor implant device  810  to the pulmonary veins. 
     In  FIG. 8 , a first anchor stent  822  is deployed in a first pulmonary vein  827 , wherein the stent  822  is associated with and/or coupled to an end portion of the bridge/arm structure  830  in accordance with embodiments of the present disclosure. The first anchor  822  is coupled to the secondary anchor  824 , which is deployed within the adjacent pulmonary vein  824 , wherein the first and second anchors  822 ,  82 . 4  are coupled to one another by the bridge or arm member(s)  830 , which may be at least partially rigid and/or flexible. In some embodiments, the bridge/arm member(s)  830  has/have shape memory and/or resilience characteristics that introduce a force on the anchors  822 ,  824  towards one another. Either or both of the anchors  822 ,  824  may be self-expanding stents. Use of two anchors may serve to provide improved anchoring for a sensor implant device in accordance with embodiments of the present disclosure. 
       FIGS. 9A and 9B  illustrate front and side views, respectively, of a sensor implant device  910  in accordance with one or more embodiments of the present disclosure. In the configuration illustrated in  FIGS. 9A and 9B , anchor devices  922 ,  924  associated with the implant device  910  are in an expanded state or configuration, wherein the anchor devices may be configured to be secured within a target implantation vessel, such as a pulmonary vein, using force exerted by the respective anchor devices in the illustrated expanded configuration. For example, the anchors  922 ,  924  can advantageously have an expanded configuration with a diameter or other dimension D that is dimensioned to be approximately equal to, or slightly greater than, a diameter of a pulmonary vein lumen at one or more longitudinal portions thereof. 
     The anchor devices  922 ,  924  can advantageously be self-expanding, or may be balloon-expanding, or otherwise configurable or expanded for securing within a blood vessel, such as a pulmonary vein. Similarly to other embodiments illustrated and described herein, the anchor devices  922 ,  924  may each be physically/mechanically coupled to a sensor module  916  using any suitable or desirable direct and/or indirect attachment mechanism. In the illustrated embodiment of  FIGS. 9A and 9B , the anchor devices are secured at least partially to the sensor module  916  (e.g., housing of the sensor transducer element  912 ) by one or more arm portions/members  931 ,  933 , respectively. As with any of the other embodiments disclosed herein, the various illustrated and called-out arm portions  931 ,  933  may be part of a single bridge/arm structure, to which the sensor module  916  is directly and/or indirectly secured. 
     The sensor module  916  may comprise a housing for the sensor transducer element  912 . For example, the sensor transducer element  912  may be nested in, secured to, and otherwise attached or coupled with one or more portions of the bridge structure  930 . In some embodiments, the sensor module  916  has associated therewith a channel, groove, and/or path  938  configured and/or dimensioned for holding or otherwise coupling a guidewire or other delivery system component therein. For example, in some implementations, a guidewire may be extended or advanced through a channel or other pathway or feature associated with the module  916 , such that the sensor implant device  910  can be advanced along a path defined by a pre-disposed guidewire in accordance with procedures associated with aspects of the present disclosure. Additionally or alternatively, the module  916  may comprise one or more features configured and/or designed to allow for coupling of the module  916  with one or more portions of the bridge structure  930 . Although stent-type anchor devices  922 ,  924 , are shown, which may be understood to represent self-expanding stent anchor devices in some implementations, the anchor devices  922 ,  924  may be any type of anchor device as described herein. 
       FIGS. 10A and 10B  illustrate front and side views, respectively, of the sensor implant device  910  shown in  FIGS. 9A and 9B , wherein one or more components of the sensor implant device  910  are configured in a collapsed or crimped state, which may be implemented in order to facilitate delivery of the implant device  910  using a catheter-based delivery system, as described in greater detail below. Specifically, the embodiments shown in  FIGS. 10A and 10B  show stent-type anchor devices  922 ,  924  in an at least partially collapsed/crimped state. For example, the stent anchor devices, or other types of anchor devices, may comprise a wireframe or other wire- and/or mesh-type structure that may assume a crimped and/or reduced-diameter state by compression thereof and/or elongation of the structure. For example, such compression may be achieved by compressing or expanding expandable strut features of the anchor(s) radially, axially, and/or circumferentially. In some embodiments, such compression/expansion of struts may result in an at least partial elongation of the stent structure with respect to a central axis thereof. The compressed anchors  922 ,  924  may have a compressed diameter d that is less the expanded diameter  . 
       FIG. 11  shows a partial cross-sectional view of a delivery system  100  for a sensor implant device  110  in accordance with one or more embodiments of the present disclosure. In some embodiments, the delivery system  100  comprises one or more catheters or sheaths used to advance and/or implant the sensor implant device  110 , which may be disposed at least partially within the delivery system  100  during a delivery process associated therewith. The implant sensor device  110  can be positioned within the delivery system  100  with a first end thereof (i.e., distal anchor  122 ) disposed distally with respect to the sensor module  116 , whereas a second/proximal anchor  124  is positioned at least partially proximately with respect to the sensor module  116 . The distal  122  and proximal  124  anchor devices may be coupled to the sensor module  116  via one of the securing arm portions  131 ,  133 , respectively. 
     In some embodiments, the delivery system  100  comprises an outer catheter or shaft  140 , which may be used to transport the sensor implant device  110  to the target implantation site. That is, the sensor implant device  110  may be advanced to the target implantation site at least partially within a lumen of the outer shaft  140 , such that the sensor implant device  110  is held and/or secured at least partially within a distal portion of the outer shaft  140 . In some embodiments, the delivery system  100  comprises a tapered nosecone feature  148 , which may facilitate advancement of the distal end of the delivery system  100  through the tortuous anatomy of the patient and/or with an outer delivery sheath or other conduit/path. The nosecone  148  may be a separate component from the outer shaft  140  or may be integrated with the outer shaft  140 . In some embodiments, the nosecone  148  is adjacent to and/or integrated with a distal end of the outer shaft  140 . In some embodiments, the nosecone is distally tapered into a generally-conical shape and may comprise and/or be formed of multiple flap-type forms that can be urged/spread apart when the sensor implant device  110  and/or any portions thereof, interior shafts, or devices are advanced therethrough. 
     The delivery system  100  may further be configured to have a guidewire  150  disposed at least partially within the delivery system  100  and/or coupled thereto in a manner to allow the delivery system  100  to follow a path defined by the guidewire  150 . The distal anchor device  122  may be contained and/or secured by the outer shaft  140 , as illustrated in  FIG. 11 . 
     The delivery system  100  may further comprise a distal inner shaft  142  disposed at least partially within the outer shaft  140  and proximal to the distal anchor device  122 , such that the distal inner shaft  142  can provide support for the distal anchor  122 . Furthermore, the distal inner shaft  142  can be configured to be used to push/advance the distal anchor device  122 , along with the remaining components of the implant device  110  coupled thereto, relative to the outer shaft  140 . Therefore, by distally advancing the distal inner shaft  142  relative to the outer shaft  140 , the distal anchor  122  and sensor implant device  110  can be distally advanced and/or deployed through a distal opening in the outer shaft  140 . While the distal anchor device  122  is disposed at least partially without the distal inner shaft  142  and/or distal thereto, one or more other components of the sensor implant device  110  may be maintained, contained, and/or disposed at least partially within the inner shaft  142  during one or more periods of a delivery process, as illustrated in  FIG. 11 . For example, the sensor module  116 , which may have associated therewith a sensor transducer element  112  as described in detail herein, as well as one or more portions of the bridge/arm structure  131 ,  133  and/or proximal anchor  124  may be contained at least partially within the distal inner shaft  142 . 
     The delivery system  100  may further comprise a proximal inner shaft  144  disposed at least partially within the distal inner shaft  142  and outer shaft  140  and proximal to the sensor module  116 , such that the proximal inner shaft  144  can provide support for the sensor module  116 . Furthermore, the proximal inner shaft  144  can be configured to be used to push/advance the sensor module  116  and/or other components of the sensor implant device  110  coupled thereto relative to the distal inner shaft  142  and/or outer shaft  140 . While the sensor module  116  is disposed at least partially without the proximal inner shaft  144  and/or distal thereto, one or more other components of the sensor implant device  110  may be contained or disposed at least partially within the proximal inner shaft  144  during one or more periods of a delivery process, as illustrated in  FIG. 11 . For example, the proximal portion  133  of the bridge/arm structure  130  and the proximal anchor device  124  may be contained at least partially within the proximal inner shaft  144 . In some implementations, the proximal portion  133  of the bridge/arm structure  130  may be configured to be positioned in the proximal inner shaft  144  and/or other component(s) of the delivery system  100  in an at least partially bent configuration, such that the proximal anchor device  124  is stored within the proximal inner shaft  144  in a cramped/collapsed state and/or in a position such that the end of the proximal anchor device  124  faces distally and a similar direction as the distal anchor device  122 . 
     The delivery system  100  may further include a proximal anchor pusher device  146  configured to be disposed against and/or contact the proximal anchor  124  and/or associated structure (e.g., arm portion  133  directly or indirectly coupled to the proximal anchor device  124 ) to allow for pushing and/or controlling/manipulating the proximal anchor device  124 . For example, the proximal anchor pusher device  146  may comprise a tubular-shaped form defining a lumen therein, as illustrated in  FIG. 11 . Alternatively, in some embodiments, the proximal anchor pusher support  124  may not include an internal axial lumen, and rather may provide a substantially solid form and/or other-shaped or configured form than that illustrated in  FIG. 11 . 
     The proximal anchor pusher support  146  may be disposed and/or contained at least partially within one or more of the outer shaft  140 , distal inner shaft  142  and/or proximal inner shaft  144 , and further may have disposed in a lumen thereof one or more components of the sensor implant device  110  and/or delivery system  100  during various periods of an associated implantation procedure. For example, in some implementations, the guidewire  150  may be disposed at least partially within the proximal anchor pusher support  146  during one or more portions of a medical procedure for implanting the sensor implant device  110 . For example, the delivery system  100  may be configured to be advanced axially along the guidewire  150  during a medical procedure, wherein the guidewire  150  may be initially placed along a path to a target implantation site, such that the delivery system can be passed over the guidewire  150 . During such process(es), the guidewire  150  may be disposed within the proximal anchor pusher support and/or proximal inner shaft  144 , distal inner shaft  142 , and/or outer shaft  140 ). 
       FIG. 12  is a flow diagram illustrating a process  200  for implanting a sensor implant device at or in target anatomy of a patient, such as within one or more cardiac chambers or vessels of a heart of the patient.  FIG. 13  illustrates images of cardiac anatomy, as well as delivery system and sensor implant device components, corresponding to the various operations described in the flow diagram of  FIG. 12 , For example,  FIG. 13  shows embodiments of a delivery system and sensor implant device that may represent example embodiments of the delivery system  100  and sensor implant device  110  shown in  FIG. 11  and described in detail above, and therefore similar reference numbers are used for convenience.  FIG. 14  illustrates front and side views, respectively, of the sensor implant device  110  in various configurations corresponding to the respective operations of the process  200  of  FIG. 12 . 
     The process  200  relates to one or more medical procedures for implanting the sensor implant device  110  at least partially within the left atrium  2  of the patient&#39;s heart using a suitable delivery system  100 . In some implementations, the process  200  may be performed in connection with a mitral valve replacements or repair procedure, or another surgical or transcatheter medical procedure requiring access to the left atrium. Therefore, although certain procedure(s) are described for accessing the left atrium, it should be understood that left atrial access by a delivery system in accordance with embodiments of the present disclosure may be made in any suitable or desirable way. For example, such access may be made using a minimally invasive procedure or using a surgical procedure incorporating access to the heart through the chest wall, such as in accordance with an open-chest procedure. 
     At block  202 , the process  200  involves advancing the delivery system/catheter  100  to the right atrium  5  of the patient&#39;s heart using a percutaneous/transcatheter access path or procedure. For example, as shown in image  302  of  FIG. 13 , access to the right atrium  5  may be made via the superior  19  or inferior  16  vena cavae, wherein access to the venous system may be made from the subclavian vein, femoral vein, or any other venous (or arterial) blood vessel. As shown in  FIG. 14 , the sensor implant device  110  may be in an at least partially collapsed/crimped configuration within the delivery system  100  when the delivery system  100  is advanced to the right atrium  5 . In some embodiments, as described in detail herein, one or more of the distal  122  and/or proximal  124  anchor devices may be axially folded inward towards an axial center of the sensor implant device  110 , as shown in image  111  with respect to the proximal anchor  124 . 
     At block  204 , the process  200  involves advancing the delivery system  100  through the inter-atrial septum  18  separating the right atrium  5  from the left atrium  2 , such that the delivery system may pass into the left atrium  2 , as shown in image  102  of  FIG. 13 . As referenced herein, such access to left atrium  2  may be made via other access routes, whereas image  102  shows a particular access route for purposes of explanation and simplicity. The operational block  204  may be performed with the sensor implant device  110  maintained in the at least partially compressed configuration shown in image  113 . 
     At block  206 , the process  200  involves advancing the delivery system  100  to, within, and/or in proximity to a pulmonary vein  26  that is fluidly coupled with the left atrium  2 , as described in detail above. Although the image  103  shows the delivery system  100  advanced to the left superior pulmonary vein  26 , it should be understood that such vein is represented in image  103  for descriptive purposes only, and any other pulmonary vein or other chamber or vessel may be engaged by the delivery system  100  in accordance with embodiments of the present disclosure. 
     At block  208 , the process  200  involves deploying a distal anchor device  122  of the sensor implant device  110  in and/or to the target pulmonary vein  26  and/or tissue associated therewith. For example, with respect to stent-type, or other expandable tissue anchor devices, as shown in image  104 , the operation associated with block  208  may involve expanding the tissue anchor device  122  within a conduit/lumen of the pulmonary vein  26 . However, alternative anchoring mechanisms or techniques may be implemented, such as anchoring tissue-embedding anchor device(s) into the interior of the pulmonary vein conduit, or to left atrial tissue proximate to the pulmonary vein  26  and/or ostium thereof. 
     As described in detail herein, the distal anchor device  122  may be coupled or associated with an arm member/portion  131 , which may be at least partially deployed from the delivery system  100  in connection with the operation associated with block  208  (and/or the operation associated with block  210 , described below). In connection with the deployment of the distal anchor device  122  in the target pulmonary vein  26 , the arm member/portion  131  may be at least partially bent or configured to accommodate the distal anchor device  122 , such that the remainder of the sensor implant device  110  may be oriented at a generally-orthogonal/perpendicular orientation with respect to the axis of the distal anchor device  122 , as shown in the accompanying image  117  of  FIG. 14 . For example, as shown in image  117 , with the distal anchor device  122  deployed from the delivery system  100 , at the stage of the process  200  associated with block  208  (and/or block  210 ), a portion  114  of the sensor implant device  110  may remain and/or be maintained within the delivery system  100  after deployment of the distal anchor device  122 . 
     At block  210 , the process  200  involves withdrawing the delivery system  100  an axial distance away from the pulmonary vein  26  in order to move the delivery system  100  and/or distal end thereof to, within, and/or into proximity with a second target pulmonary vein  23 , which may thereby serve to deploy from the delivery system  100  one or more components or portions of the sensor implant device  110 , such as one or more portions or components of the bridge/arm structure (e.g., portion  131 ) and/or sensor module  116 , as shown in image  105 , With the delivery catheter moved or approximated to the second target pulmonary vein  23 , the portion  118  of the sensor implant device  110  that remains within the delivery system may include the proximal anchor device  124  and/or one or more portions  133  of the bridge/arm structure of the sensor implant device  110 . That is, the sensor implant device  110  may be in a position/configuration in which the sensor module  116  is deployed from the delivery system  100  at a stage associated with the operation of block  210 . 
     At block  212 , the process  200  involves deploying the proximal anchor device  124  in the second target pulmonary vein  23 . For example, the proximal anchor device  124  may be deployed and/or engaged in/with the second target pulmonary vein  23  in any suitable or desirable way, as described in detail herein. For example, the proximal anchor device  124  may comprise any suitable or desirable type of tissue anchor or securing device(s), whether expansion-type or tissue-embedding/suturing type anchor device(s), and whether anchored to the inside wall of the conduit of the pulmonary vein  23  and/or the left atrial tissue at or proximate to the ostium of the pulmonary vein  23 . In deploying the proximal anchor device  124  and the pulmonary vein  23 , the arm portion  133  coupling the proximal tissue anchor  124  to the remaining structure of the sensor implant device  110  may be unbent, or otherwise oriented or bent in order to allow for the anchor device  124  to be substantially coaxial with the pulmonary vein  23 , while allowing the remainder of the bridge structure  130  of the sensor implant device  110  to bridge between the first target pulmonary vein  26  and the second target pulmonary vein  23 . Although the second target pulmonary vein  23  is illustrated as corresponding to the right superior pulmonary vein, it should be understood that the second target pulmonary vein may be any suitable or desirable pulmonary vein, as described in detail below relative to  FIGS. 15, 16, 17 , and/or  18 . 
     At block  214 , the process  200  involves withdrawing the delivery catheter from the heart and/or body of the patient, thereby leaving or maintaining the sensor implant device  110  as implanted in and/or otherwise engaged with the target pulmonary veins  26 ,  23 , as described above. Therefore, the sensor implant device  110  may be maintained in a shape or configuration similar to that shown in image  123  of  FIG. 14  after implantation thereof. 
       FIGS. 6 and 13 , described in detail above, illustrate for reference sensor implant devices implanted between a left superior pulmonary vein at a distal end of the sensor implant device and a right superior pulmonary vein at a proximal end of the sensor implant device. Furthermore,  FIG. 8  illustrates a sensor implant device implanted between a left superior pulmonary vein and a left inferior pulmonary vein. However, it should be understood that such particular implementations are shown for illustrative purposes only, and implantation of sensor implant devices in accordance with embodiments of the present disclosure may be implanted between any two of the pulmonary veins (or other blood vessel), and/or may be implanted and/or secured to only a single pulmonary vein, or to three or more pulmonary veins. 
       FIG. 1.5  illustrates a left atrium  2  and associated anatomy, including pulmonary veins, wherein a sensor implant device  310  is implanted between a left inferior pulmonary vein  25  and a right superior pulmonary vein  23 . Either the left inferior pulmonary vein  25  or the right superior pulmonary vein  23  may be considered the distal end or the proximal end of the sensor implant device  310  with respect to an implantation procedure implemented in connection with  FIG. 1.5 . The implantation orientation of the sensor implant device  310  as in  FIG. 15  may be implemented in connection with any of the embodiments of the present disclosure, such as an alternative to any other illustrated and/or described orientations associated with the respective embodiments. 
       FIG. 16  illustrates a left atrium  2  and associated anatomy, including pulmonary veins, wherein a sensor implant device  311  is implanted between a left inferior pulmonary vein  25  and a right inferior pulmonary vein  21 . Either the left inferior pulmonary vein  25  or the right inferior pulmonary vein  21  may be considered the distal end for the proximal end of the sensor implant device  311  with respect to an implantation procedure implemented in connection with  FIG. 16 . The implantation orientation of the sensor implant device  311  as in  FIG. 16  may be implemented in connection with any of the embodiments of the present disclosure, such as an alternative to any other illustrated and/or described orientations associated with the respective embodiments. 
       FIG. 17  illustrates a left atrium  2  and associated anatomy, including pulmonary veins, wherein a sensor implant device  312  is implanted between a left superior pulmonary vein  27  and a right inferior pulmonary vein  21 . Either the left superior pulmonary vein  27  or the right inferior pulmonary vein  21  may be considered the distal end or the proximal end of the sensor implant device  312  with respect to an implantation procedure implemented in connection with  FIG. 17 . The implantation orientation of the sensor implant device  312  as in  FIG. 17  may be implemented in connection with any of the embodiments of the present disclosure, such as an alternative to any other illustrated and/or described orientations associated with the respective embodiments. 
       FIG. 18  illustrates a left atrium  2  and associated anatomy, including pulmonary veins, wherein a sensor implant device  313  is implanted between a right inferior pulmonary vein  21  and a right superior pulmonary vein  23 . Either the right inferior pulmonary vein  21  or the right superior pulmonary vein  23  may be considered the distal end or the proximal end of the sensor implant device  313  with respect to an implantation procedure implemented in connection with  FIG. 18 . The implantation orientation of the sensor implant device  313  as in  FIG. 18  may be implemented in connection with any of the embodiments of the present disclosure, such as an alternative to any other illustrated and/or described orientations associated with the respective embodiments. 
     Although various embodiments of the present disclosure are described in the context of sensor implant devices that are anchored using a plurality of stent-type anchors or other types of anchors, it should be understood that sensor devices in accordance with embodiments of the present disclosure may be supported and/or anchored by a single stent-type anchor or other type of anchor.  FIG. 19A  shows a side deployed view of a sensor implant device  40  anchored in a blood vessel  35  in accordance with one or more embodiments.  FIG. 19B  shows an axial view of the sensor implant device  40  of  FIG. 19A  in accordance with one or more embodiments.  FIG. 19C  shows a side view of the sensor implant device  40  of  FIG. 19A  in accordance with one or more embodiments. 
     The sensor implant device  40  shown in  FIGS. 19A-19C  includes a single stent anchor  41 , wherein a sensor device  43  is physically coupled thereto in some manner. For example, in some embodiments, a support arm  44  may be attached to and/or integrated with the stent frame  41  and may mechanically couple the sensor device  43  to the anchor frame  41 . In such a configuration, the sensor device  43  may extend axially from an end of the anchor frame  41 , and possibly into a chamber or blood vessel into which the blood vessel  35  opens, wherein constituents of blood or other fluid present in such chamber/vessel are sensed by the sensor device  43 , such as blood/fluid pressure or the like. 
     In some implementations, the anchor  41  may be anchored within a cardiac blood vessel such as within a pulmonary vein and/or ostium thereof, as described in detail herein. In such a configuration, the sensor device  43  may be exposed to blood/fluid within the left atrium, benefits of which are described above in detail. 
     With respect to any of the embodiments shown and described in connection with  FIGS. 6-18 , sensor support arm/strut features of such embodiments, as with any of the embodiments of  FIGS. 19-31 , may comprise separate bar-type features that are fixed to the respective stent anchors (or other types of anchors), or they may be integrated with the frames/forms of the respective anchors. It should be understood that any of the features of the sensor implant devices disclosed in connection with  FIGS. 6-18  may be implemented in any of the sensor implant devices disclosed in connection with  FIGS. 19-31 , and any of the features of the sensor implant devices disclosed in connection with  FIGS. 19-31  may be implemented in any of the sensor implant devices disclosed in connection with  FIGS. 6-18 . 
     As shown in  FIG. 19A , the sensor device  43  and/or support arm  44  may be deflected radially outward with respect to the axis of the anchor frame  41 , such that the sensor device  43  is substantially parallel to the tissue wall  31  (e.g., interior left atrium wall) outside of the anchoring vessel  35 , or at an acute angle with respect to the tissue wall  31 . Outward deflection of the sensor device  43  and/or support arm  44  may be achieved through manual bending of the support arm  44 , or through autonomous movement/deflection of the sensor-support arm  44  caused by shape-memory characteristics/features of the arm  44 . In some embodiments, the sensor-support arm  44  may be integrally formed with the anchor frame  41 . For example, the support arm  44  may extend from one or more strut or extension features of the support frame  41 . Such features may be laser-cut from a metal sheet/form to form an expandable stent frame and sensor-support arm/extension extending from the frame as an integral extension/feature thereof. 
       FIG. 19B  shows an axial view of the sensor implant device  40 , wherein the sensor device  43  and/or the sensor-support arm  44  are deflected radially outward. When implanted, the sensor transducer element/portion  45  of the sensor device  43  may be exposed outward (i.e., facing out of the page with respect to the illustrated orientation of  FIG. 1913 ). With the sensor device  43  deflected away from the barrel/cylinder  46  of the anchor frame  41 , readings of the sensor device  43  may be less directly tied to the flow through the barrel  46 , and rather may be indicative of parameters of the blood in the chamber into which the vessel  35  opens. 
       FIG. 19C  shows a side view of the sensor implant device  40  in a compressed state, in which the stent frame  41  is radially compressed to fit within, for example, a delivery catheter or other delivery system device/component. In the delivery configuration shown in  FIG. 19C , the sensor-support arm  44  may be configured in a substantially straight configuration, such that the sensor device  43  is not deflected radially outward as in the deployed configuration of  FIGS. 19A and 1913 . Such straightened configuration may facilitate disposal in a cylindrical delivery catheter or other delivery component/device. As with any of the other embodiments disclosed herein relating to sensor devices that are supported by a sensor-support arm/strut associated with a vessel anchor, the sensor device  43  may be attached or coupled to the support arm/strut  44  in any suitable or desirable way. For example, the sensor device  43  may be secured to the support arm  44  using an adhesive, or other means. In some embodiments, a mechanical coupling is implemented between sensor device  43  and the arm  44 . For example, the sensor device  43  may sit within a recess or other feature configured to engage the sensor housing around at least a portion of a circumference thereof. In some embodiments, the support arm  44  may include a hook, clasp, clip, or other locking/engagement feature configured to engage with an aperture or other opening feature of the sensor housing, or vice versa. 
       FIG. 20A  shows a side deployed view of a sensor implant device  50  anchored in a blood vessel  35 , such as a pulmonary vein and/or pulmonary vein ostium, in accordance with one or more embodiments.  FIG. 20B  shows an axial view of the sensor implant device  50  of  FIG. 20A  in accordance with one or more embodiments.  FIG. 20C  shows a side view of the sensor implant device  50  of  FIG. 20A  in a delivery configuration in accordance with one or more embodiments. Unlike  FIGS. 19A-19C , which illustrates a sensor implant device  40  including a sensor  43  supported by an arm/strut feature  44 , which extends axially from an end of the stent anchor frame  41 , the embodiments of the sensor implant device  50  shown in  FIGS. 20A-20C  include a sensor device  53  that is secured to the anchor frame  51  through direct attachment to the inner diameter thereof. That is, the sensor device  53  may be embedded and/or secured in some manner in/to the stent frame  51  without the need/use of an axially extending support arm/strut. 
     With the sensor device  53  secured to the inner diameter/surface of the anchor frame  51 , the sensor transducer feature/element  55  may be generally exposed within the inner barrel  56  of the device  50 . Therefore, with the anchor frame  51  anchored within a blood vessel  35 , such as a pulmonary vein, the sensor transducer  55  may be configured to sense characteristics of blood flow through the blood vessel  35  and stent frame  51 . In some cases, the fluid pressure within the pulmonary vein or other blood vessel  35  may be different than that in the chamber (e.g., left atrium) outside of the blood vessel  35 . Therefore, this position of the sensor device  53  within the inner diameter of the stent frame  51  may allow for sensing of fluid characteristics that may be different from corresponding characteristics of fluid present outside of the blood vessel  35 , such as flow, pressure, and/or other sensed characteristics. 
     As shown, the sensor device  53  may be attached to the frame  51  at or near a distal end of the frame  51  (i.e., on a left side of the frame  51  in the illustrated orientation of  FIG. 20A ). In some embodiments, the sensor device  53  may be secured to the inner diameter of the frame  51  through adhesive, welding, and/or other permanent or temporary fixation means. For example, in some embodiments, the housing of the sensor  53  may be configured to be snapped, hooked, clipped, clasped, and/or otherwise engaged with the frame  51 , such as within one or more cells of the frame lattice, to provide a mechanical attachment/locking connection between the sensor  53  (and/or sensor housing) and the frame. 
     As shown in  FIG. 20B , which shows an axial view of the sensor implant device  50 , the sensor device  53  may be configured to fit within the barrel  56  of the device  50 , wherein the sensor transducer element/feature  55  of the sensor device  53  generally faces radially inward. In some embodiments, the sensor transducer  55  may be generally axially oriented, such that the face thereof faces with or opposing the flow of fluid through the barrel  56 . 
       FIG. 20C  shows the sensor implant device  50  in a compressed delivery configuration. For example, the anchor frame  51  may be radially crimped/compressed to allow for a smaller diametrical profile for disposing within a delivery catheter or other delivery device. The sensor device  53  may advantageously be small enough such that radial crimping of the anchor frame  51  is not impeded by the presence of the sensor device  53  within the barrel  56  of the anchor frame  51 . 
       FIG. 21A  shows a side deployed view of a sensor implant device  60  anchored in a blood vessel  35  in accordance with one or more embodiments.  FIG. 21B  shows an axial view of the sensor implant device  60  of  FIG. 21A  in accordance with one or more embodiments.  FIG. 21C  shows a side view of the sensor implant device  60  of  FIG. 21A  in a delivery configuration in accordance with one or more embodiments. 
     The sensor implant device  60  illustrated in  FIGS. 21A-21C  is similar in various respects to the sensor implant device  40  shown in  FIGS. 19A-19C  and described above. However, unlike the sensor implant device  40  shown in  FIG. 19A , the sensor implant device  60 , shown in  FIG. 21A  in a deployed configuration, may not be radially deflected when deployed. For example, as shown, the sensor-support arm/strut  64  may extend axially from an end of the stent frame  61  (i.e., left-most end of the frame  61  in the illustrated orientation of  FIG. 21A ) in a generally straight configuration. Iii the straight configuration shown in  FIG. 21A , the sensor transducer  65  may generally face radially inward with respect to the axis of the anchor frame  61 . However, it should be understood that in some embodiments, the sensor transducer  65  may face radially outward and/or axially distally or proximally with respect to the orientation of the anchor frame  61 . 
     With respect to the axial view of  FIG. 21B , the radially-inward-facing orientation of the sensor device  63  and/or sensor transducer  65  is demonstrated, wherein the sensor transducer  65  lies within the radius of the barrel  56  of the frame  61 , albeit in a position that is axially extended beyond the end of the frame  61 . In the delivery configuration, as shown in  FIG. 21C , the sensor device  63  may be supported by a generally straight support strut/arm  64  during delivery thereof. 
       FIG. 22A  shows a side deployed view of a sensor implant device  70  anchored in a blood vessel  35  in accordance with one or more embodiments.  FIG. 22B  shows an axial view of the sensor implant device  70  of  FIG. 22A  in accordance with one or more embodiments.  FIG. 22C  shows a side view of the sensor implant device  70  of  FIG. 2.2A  in a delivery configuration in accordance with one or more embodiments. 
     In the embodiments of  FIGS. 22A-22C , the sensor device  73  is supported by a plurality of support arms  74   a ,  74   b . For example, the sensor device  73  may be held at or near an axial center of the barrel  76  of the anchor frame  71 , which may be deployed/implanted within a blood vessel  35 , such as a pulmonary vein. In some embodiments, the arms  74   a ,  74   b  may hold the sensor device  73  in a position axially beyond the end  78  of the anchor frame  71  (i.e., the leftmost end of the frame  71  with respect to the illustrated orientation of  FIG. 22A ), such that the sensor device  73  is disposed some distance the in front of i.e., to the left of with respect to  FIG. 22A ) the anchor frame  71  and/or ostium of the blood vessel  35 . In some embodiments, the support arms/struts  74   a ,  74   b  hold the sensor device  73  within the axial bounds of the support frame  71 . That is, unlike the illustrated implementation shown in  FIG. 22A , in some embodiments, the sensor device  73  may be held axially within the anchor frame  71 . 
       FIG. 22B  shows the sensor device  73  held by the support arms  74   a ,  74   b  within the radius of the barrel  76  of the anchor frame  71 , albeit axially beyond the end of the frame  71 . The sensor device  73  may include one or more sensor transducer features/elements  75 ,  77 . For example, the sensor transducer  77  is shown as facing against of the flow of fluid through the anchor frame  71 , and therefore may be configured and/or disposed in a position to sense parameters associated with such fluid flow incident on the fate of the transducer  77 . In some embodiments, the sensor device  73  includes a sensor transducer  75  facing axially outward with respect to the orientation of the anchor frame  71 . With the outward-facing transducer  75 , the sensor  73  may be configured to sense parameters of the fluid within the chamber (e.g., left atrium) outside of the blood vessel  35  that is less affected by the flow through the anchor frame  71  than with respect to sensor transducers facing axially inward, as with the illustrated transducer  77 . Although two sensor transducers are shown in  FIGS. 22A and 22C , it should be understood that any number of such transducers, including a single such transducer, may be implemented in connection with the embodiments of  FIGS. 22A-22C . 
     The arms  74   a ,  74   b  may attached to the housing/structure of the sensor  73  in any suitable or desirable manner. In some embodiments, the arms are configured to hook or otherwise engage into/with eyelet/aperture features of the sensor housing to create a mechanical coupling therewith. In some embodiments, the arms  74   a ,  74   b  form or are associated/integrated with a circumferential sensor-retention band or cup feature in which the sensor device  73  may be disposed/secured. The sensor device  73  may be secured to the arms  74   a ,  74   b  and/or associated sensor-retention features thereof through tension fit or other mechanical attachment mechanism. In the delivery configuration shown in  FIG. 22C , the support arms  74   a ,  74   b  may assume a bent configuration, wherein such bends are at sharper angles than the bends of the arms  74   a ,  74   b  in the deployed configuration shown in  FIG. 22A . In the delivery configuration, the sensor device  73  may be already coupled to the support arms  74   a ,  74   b , such that in deployment, no attachment of the sensor device  73  to the support arms  74   a ,  74   b  is necessary. 
       FIG. 23  shows a sensor implant device  80  implanted in the superior and inferior vena cavae in accordance with one or more embodiments. The sensor implant device  80  includes a sensor  83  coupled to one or more stent-like anchors  81   a , Sib configured to be anchored within the superior  19  and inferior  16  vena cava, respectively. For example, the sensor  83  may be coupled to the stent anchors via one or more arms/connectors  84 . For example, the first arm portion  84   a  may physically extend between the sensor  83  and the stent anchor  81   a , whereas the arm portion  84   b  may extend between the sensor  83  and the stent anchor  81   b . The arm(s)  84  may comprise a single bar extending between the stent anchor  81   a  and the stent anchor  81   b , wherein the sensor  83  is secured in some manner to the bar  84 . In some embodiments, the portions  84   a ,  84   b  represent physically separate arm segments extending from the sensor  83 . The sensor  83  may be coupled to the arm(s)  84  in any suitable or desirable manner, such as through the use of one or more adhesives, clips, fittings, and/or other coupling features. 
     With the sensor  83  coupled to one or more stent anchors  81  as in  FIG. 23 , the sensor  83  may generally be disposed and exposed within the right atrium  5  of the heart. The use of a sensor, such as a pressure sensor, within the right atrium can provide readings indicating central venous pressure (CBP) or other parameter associated with central venous blood flow. 
     In some embodiments, one or more of the anchors  31  may include certain valve features  88 . For example, such valve features may be one-way valves, which may allow fluid flow into the right atrium from the inferior and/or superior vena cavae, while impeding our preventing blood flow from the right atrium  5  into the superior  19  and/or inferior vena cavae. In embodiments in which one or more anchors  81  include one-way valves allowing outflow into the right atrium, such valve(s) can prevent or reduce backflow into the veins, thereby reducing the risk and/or occurrence of edema, swelling, and/or other medical conditions. Although embodiments of the present disclosure are described herein including one or more stent anchors with valve features anchored in one or more of the superior and inferior vena cavae, wherein such anchor(s) are coupled to a sensor that is exposed at least partially within the right atrium, in some embodiments, valved stent anchors may be implanted/disposed within the vena cava without an associated/coupled sensor device. That is, the anchors may be used for the purpose of preventing backflow of blood into the veins, with or without associated sensor functionality/feature(s). 
     In embodiments that do not include a sensor device, any physical coupling  84  between the anchors  81  that may be present may be used as a docking structure for any type of implant device. Furthermore, even in embodiments that include a sensor device, such as is shown in  FIG. 23 , the coupling arm  84  may be used for docking one or more additional implant devices or components, such as spacer devices, replacement valves, or the like. For example, in some embodiments, a replacement valve device, such as a replacement tricuspid valve, may be implanted within the annulus of the tricuspid valve  8  and further secured or docked to the arm structure  84  and/or one or more of the blood vessel anchors  81 . In some embodiments, a tricuspid valve spacer device may be anchored to the coupling arm  84  and/or one or more of the stent anchors  81 . The optional valve features  88  may comprise 2, 3, or other number of leaflets, which may be formed of biological and/or synthetic material(s). 
     The sensor implant device  80  may be implanted in any suitable or desirable manner. For example, implanting the sensor implant device  80  may involve advancing a delivery system, which may include one or more delivery catheters, into to a first vena cava of the patient, either the superior vena cava  19  or the inferior vena cava  16 , via a transcatheter access path, as shown and described in connection with  FIG. 32 . The method may further involve advancing the delivery system through at least a portion of a right atrium  5  of the patient and into a second vena cava of the patient (i.e., the other of the superior vena cava  19  and the inferior vena cava  16 ), deploying a distal anchor (i.e., a first one of the anchors  81   a ,  81   b , depending on which of the vena cavae the anchor is being deployed in) of a sensor implant device from the delivery system, anchoring the distal anchor of the sensor implant device within the second vena cava. The delivery system may then be withdrawn through the at least a portion of the right atrium  5 , thereby exposing at least a portion of the sensor device  83  of the sensor implant device, as well as a first support arm portion (i.e., either  84   a  or  84   b , or both) coupling the sensor device to the distal anchor, in the right atrium  5 . The process may further involve deploying a proximal anchor of the sensor implant device (i.e., a second one of the anchors  81   a ,  81   b , depending on which of the vena cavae the anchor is being deployed in) from the delivery system within the first vena cava, and anchoring the proximal anchor of the sensor implant device to within the first vena cava. The delivery system may then be withdrawn from the patient. 
       FIGS. 24A-C  show crimped side, expanded front, and axial views, respectively, of a sensor implant device in accordance with one or more embodiments. In particular,  FIG. 24A  shows the cardiac implant device  80  of  FIG. 23  in an at least partially crimped/compressed delivery configuration. In the delivery configuration shown in  FIG. 24A , the one or more stent anchors  81  may be radially compressed such that a cross-sectional profile thereof is sufficiently small to fit within the delivery catheter or other delivery device or system component. It should be understood that the coupling arm segments  84  may have any suitable or desirable length. 
       FIG. 24B  shows a front view of the device  80 , wherein the sensor transducer  85  is shown. In the configuration of  FIG. 24B , the sensor implant device  80  is in a deployment configuration, wherein the stent anchors  21  are at least partially expanded for contact with respective blood vessel walls of the superior and inferior vena cavae. The images of  FIGS. 24A and 24B  show the optional valve features  88   a  and  88   b  associated with the anchors  81   a  and  81   b , respectively. The illustrated embodiment includes one or more 3-leaflet valves. However, it should be understood that valve features associated with anchors disclosed herein have any number of leaflets and/or other valve component or features. 
       FIG. 24C  shows an axial view of the device  80  showing the sensor  83  and the valve feature  88   b . As shown, the sensor transducer  85  may be disposed within and/or facing radially inward with respect to the radius/diameter of the anchor  81 . Therefore, blood flow through the anchor valve  88  may be directed generally in the direction of the sensor device  53 , some of which may pass over the sensor transducer  85 . 
       FIG. 25  shows a sensor implant device  90  anchored in a superior vena cava  19  in accordance with one or more embodiments. The sensor implant device  90  includes a sensor device  93  mechanically coupled to and/or otherwise associated with the inner diameter of the stent anchor  91 . That is, the sensor  93  may not be coupled to the anchor  91  by an extended arm feature, as in  FIG. 23 , but rather may be disposed at least partially within the inner diameter of the stem anchor  91 . The stent anchor  91  is disposed in the superior vena cava  19  and therefore the sensor  93  may be configured to determine certain parameters associated with blood flow into the right atrium  5  from the superior vena cava  19 . 
       FIG. 26  shows a sensor implant device  96  anchored in an inferior vena cava  16  in accordance with one or more embodiments. The sensor implant device  96  includes a sensor device  94  mechanically coupled to and/or otherwise associated with the inner diameter of the stent anchor  92 . That is, the sensor  94  may not be coupled to the anchor  92  by an extended arm feature, as in  FIG. 23 , but rather may be disposed at least partially within the inner diameter of the stent anchor  92 . The stent anchor  92  is disposed in the inferior vena cava  16  and therefore the sensor  94  may be configured to determine certain parameters associated with blood flow into the right atrium  5  from the inferior vena cava  19 . 
       FIG. 27  shows a sensor implant device  270  anchored in a superior vena cava  19  in accordance with one or more embodiments. The sensor implant device  270  includes a sensor device  275  mechanically coupled to a stent anchor  271  via a coupling arm  274 , which may be similar in certain respects to any of the other coupling arm features disclosed in connection with various embodiments of the present disclosure. The coupling arm  274  may have any suitable or desirable length. For example, the length of the coupling arm  274  may be selected to project the sensor device  273  a desired distance into the right atrium  5 , Although the sensor transducer  275  is illustrated as being oriented and/or facing inward with respect to an axis of the anchor  271 , as with any other embodiment disclosed herein, it should be understood that the sensor device  273  may have sensor transducer(s) configured and/or oriented in any suitable or desirable way. Furthermore, although the coupling arm  274  is shown as a generally straight, it should be understood that the arm  274  may have any length, shape, and or configuration. For example, in some embodiments, the arm  274  may be deflected towards a center of the right atrium  5  to thereby provide a more central position for the sensor device  273  with respect to the right atrium  5 . 
       FIG. 28  shows a sensor implant device  280  anchored in an inferior vena cava  16  in accordance with one or more embodiments. The sensor implant device  280  includes a sensor  283  mechanically coupled to a stent anchor  281  via a coupling arm  284 , which may be similar in certain respects to any of the other coupling arm features disclosed in connection with various embodiments of the present disclosure. The coupling arm  284  may have any suitable or desirable length. For example, the length of the coupling arm  284  may be selected to project the sensor device  283  a desired distance into the right atrium  5 . Although the sensor transducer  285  is illustrated as being oriented and/or facing inward with respect to an axis of the anchor  281 , as with any other embodiment disclosed herein, it should be understood that the sensor device  283  may have sensor transducer(s) configured and/or oriented in any suitable or desirable way. Furthermore, although the coupling arm  284  is shown as a generally straight, it should be understood that the arm may have any length, shape, and or configuration. For example, in some embodiments, the arm  284  may be deflected towards a center of the right atrium  5  to thereby provide a more central position for the sensor device  283  with respect to the right atrium  5 . 
       FIG. 29  shows a sensor implant device  290  anchored at least partially within a coronary sinus  16  and/or ostium  14  thereof. The sensor implant device  290  includes a sensor device  293 , which may be similar in certain respects to various other embodiments disclosed herein. The sensor device  293  is coupled to the anchor  291  via a coupling arm  294 , as with other embodiments disclosed herein. In some embodiments, the implant device  290  does not include a sensor and/or sensor coupling arm, but rather includes a valve feature or other feature associated with the stent anchor  291 . 
     Anchoring of a sensor implant device at least partially within the coronary sinus can allow for placement of an associated sensor within and/or near the right atrium, which may allow for measurement of central venous blood pressure and/or other parameter(s) associated with central venous flow and/or the right atrium. For example, sensors associated with implant devices anchored to/in the coronary sinus may be used to sense/determine various hemodynamic parameters, such as central venous pressure, blood viscosity, pulmonary artery pressure, and/or other parameter(s). As with any other stent-type anchor embodiment disclosed herein, such anchors may be self-expandable or balloon-expandable. For example, a delivery catheter may be used to deliver and/or implant the anchor device  291 . The location of the sensor anchor  291  at or near the coronary sinus ostium  14  can be used for attaching biodegradable or drug-eluding devices and/or may be used as an anchor for various medical device implants, including replacement valve devices, valve spacer devices, and/or the like. 
     Although stent anchors are generally described and illustrated in connection with the present disclosure, it should be understood that such anchors may have any suitable form, shape, and/or configuration. For example, in some embodiments, other types of anchor features are implemented, including spiral wire anchors, barbs, and/or other types of tissue anchors. 
     The sensor coupling arm  294  may have any suitable or desirable length, wherein such length may be designed to project the sensor  293  a desired distance into the right atrium  5  and/or coronary sinus ostium  14 .  FIG. 30  shows an example implant device  305 , wherein the sensor device  308  associated therewith is coupled to the associated stent anchor  306  via a relatively short coupling strut or arm  309 , such that the sensor  308  projects only a short distance past the axial end of the anchor  306 . For example, the sensor  308  may be merely clipped or secured to a strut feature of one or more cells of the stent  306  without utilizing an extended arm feature extending from the lattice of the stent. 
       FIG. 31  shows a sensor implant device  320  disposed/deployed within the coronary sinus  16  and/or coronary sinus ostium  14 , wherein the device  320  includes a sensor device  323  disposed at least partially within an inner diameter of an anchor  321  of the device  320 . For example, the sensor device  323  may be secured or attached to one or more cells of a stent-type lattice of the anchor  321  through any type of attachment means, including one or more clips, books, straps, collars, and/or any other type of mechanical and/or tension fit. 
     Sensor implant devices in accordance with one or more embodiments of the present disclosure may be advanced to the left atrium using any suitable or desirable procedure. For example, although access to the left atrium is illustrated and described in connection with certain embodiments as being via the right atrium and/or inferior vena cavae, such as through a transfemoral or other transcatheter procedure, other access paths/methods may be implemented in accordance with embodiments of the present disclosure, as described/shown in connection with  FIG. 32 . For example,  FIG. 32  illustrates various access paths through which access to the left ventricle may be achieved, including transseptal access  401   a ,  401   b , which may be made through the inferior vena cava  16  or superior vena cava  32 , as respectively shown, and from the right atrium  5 , through the septal wall (not shown) and into the left atrium  2 . For transaortic access  402 , a delivery catheter may be passed through the descending aorta, aortic arch  12 , ascending aorta, and aortic valve  7 , and into the left atrium  2  through the mitral valve  6 . For transapical access  403 , access may be made directly through the apex of the heart into the left ventricle  3 , and into the left atrium  2  through the mitral valve  6 . Other access paths are also possible beyond those shown in  FIG. 32 . 
     Additional Embodiments 
     Depending on the embodiment, certain acts, events, or functions of any of the processes described herein can be performed in a different sequence, may be added, merged, or left out altogether. Thus, in certain embodiments, not all described acts or events are necessary for the practice of the processes. 
     Certain standard anatomical terms of location are used herein with respect to the preferred embodiments. Although certain spatially relative terms, such as “outer,” “inner,” “upper,” “lower,” “below,” “above,” “vertical,” “horizontal,” “top,” “bottom,” and similar terms, are used herein to describe a spatial relationship of one device/element or anatomical structure to another device/element or anatomical structure, it is understood that these terms are used herein for ease of description to describe the positional relationship between element(s)/structures(s), as illustrated in the drawings. Spatially relative terms are intended to encompass different orientations of the element(s)/structures(s), in use or operation, in addition to the orientations depicted in the drawings. For example, an element/structure described as “above” another element/structure may represent a position that is below or beside such other element/structure with respect to alternate orientations of the subject patient or element/structure, and vice-versa. 
     Conditional language used herein, such as, among others, “can,” “could,” “might,” “may,” “e.g.,” and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is intended in its ordinary sense and is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without author input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment. The terms “comprising,” “including,” “having,” and the like are synonymous, are used in their ordinary sense, and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations, and so forth. Also, the term “or” is used in its inclusive sense and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term “or” means one, some, or all of the elements in the list. Conjunctive language such as the phrase “at least one of X, Y and Z,” unless specifically stated otherwise, is understood with the context as used in general to convey that an item, term, element, etc. may be either X, Y or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require at least one of X, at least one of Y and at least one of Z to each be present. As used herein, the term “and/or” used between the last two of a list of elements means any one or more of the listed elements. For example, the phrase “A, B, and/or C” means “A,” “B,” “C,” “A and B,” “A and C,” “B and C,” or “A, B, and C.” 
     It should be understood that certain ordinal terms (e.g., “first” or “second”) may be provided for ease of reference and do not necessarily imply physical characteristics or ordering. Therefore, as used herein, an ordinal term (e.g., “first,” “second,” “third,” etc.) used to modify an element, such as a structure, a component, an operation, etc., does not necessarily indicate priority or order of the element with respect to any other element, but rather may generally distinguish the element from another element having a similar or identical name (but for use of the ordinal term). In addition, as used herein, indefinite articles (“a” and “an”) may indicate “one or more” rather than “one.” Further, an operation performed “based on” a condition or event may also be performed based on one or more other conditions or events not explicitly recited. 
     With respect to the various methods and processes disclosed herein, although certain orders of operations or steps are illustrated and/or described, it should be understood that the various steps and operations shown and described may be performed in any suitable or desirable temporal order. Furthermore, any of the illustrated and/or described operations or steps may be omitted from any Riven method or process, and the illustrated/described methods and processes may include additional Operations or steps not explicitly illustrated or described. 
     It should be appreciated that in the above description of embodiments, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that any claim require more features than are expressly recited in that claim. Moreover, any components, features, or steps illustrated and/or described in a particular embodiment herein can be applied to or used with any other embodiment(s). Further, no component, feature, step, or group of components, features, or steps are necessary or indispensable for each embodiment. Thus, it is intended that the scope of the inventions herein disclosed and claimed below should not be limited by the particular embodiments described above but should be determined only by a fair reading of the claims that follow.