COMPOSITIONS, METHODS AND SYSTEMS FOR IDENTIFYING THE POSITION AND ORIENTATION OF THE ESOPHAGUS IN ATRIAL FIBRILLATION ABLATION PROCEDURES

Abstract

The present invention is directed to compositions, methods and systems for identifying, in real time, the position and orientation of the esophagus prior to and during atrial fibrillation ablation procedures, so as to avoid or reduce the incidence of atrioesophageal fistula (AEF). The compositions, methods and systems of the present invention include the identification and visualization of the esophagus, the rapid and accurate integration of the visualized esophagus into an anatomical map together with the posterior wall of the left atrium, in each case presented as a 3-D map, so as to facilitate the accurate identification of those areas of the esophagus that lie in contact with or in near proximity to those areas of the posterior wall of the left atrium that the operator intends to ablate.

Claims

1. A method comprising: introducing a composition into an esophagus; obtaining an image of said esophagus using a sensor disposed within a portion of a heart proximate to said esophagus; creating a three-dimensional (3-D) esophageal representation using said image; superimposing said 3-D esophageal representation onto a 3-D left atrial representation; and determining a correspondence between said 3-D esophageal representation and said 3-D left atrial representation.

2. The method of claim 1, wherein said composition comprises an echocontrast agent.

3. The method of claim 2, wherein said composition further comprises a radiocontrast agent.

4. The method of claim 1, wherein generating said 3-D esophageal representation comprises: tracing at least a portion of said esophagus within said image to define an esophageal contour.

5. The method of claim 1, wherein said correspondence is a radial distance between a posterior wall of a left atrium of said heart and an anterior wall of said esophagus, a lateral position of said esophagus relative to said posterior wall of said left atrium, or a combination thereof.

6. The method of claim 1, wherein obtaining said image comprises: directing ultrasonic energy towards the esophagus via a left atrium wall of said heart.

7. The method of claim 1, further comprising: introducing a radiocontrast agent into said esophagus; and obtaining a fluoroscopic image of said esophagus.

8. The method of claim 1, further comprising: obtaining an additional image of said esophagus using said sensor subsequent to said esophagus being translated from a first position to a second position distinct from said first position; updating said 3-D esophageal representation using said additional image; and determining an updated correspondence between said 3-D esophageal representation and said 3-D left atrial representation.

9. The method of claim 1, further comprising: dynamically updating said 3-D esophageal representation in real-time as additional image data is obtained using said sensor.

10. The method of claim 1, further comprising: obtaining fluoroscopic image data of said esophagus enhanced with a radiocontrast agent; and validating said correspondence between said 3-D esophageal representation and said 3-D left atrial representation using said fluoroscopic image data.

11. The method of claim 10, wherein said fluoroscopic image data is generated via fluoroscopy of a duration selected from the group consisting of: five seconds or less, one second to two seconds or less, and less than one second.

12. The method of claim 11, wherein said composition comprises: one or more echocontrast agents and one or more viscosity agents; one or more echocontrast agents and one or more carrier solutions; one or more echocontrast agents, one or more viscosity agents and one or more carrier solutions; one or more echocontrast agents and one or more radiocontrast agents; one or more echocontrast agents, one or more radiocontrast agents and one or more carrier solutions; one or more echocontrast agents and one or more coating agents; or one or more echocontrast agents, one or more coating agents and one or more carrier solutions.

13. A system comprising: a sensor; a processor; and a computer-readable storage medium comprising instructions that, upon execution by the processor, cause the system to perform operations, the operations comprising: obtaining an image of an esophagus injected with a composition while said sensor is disposed within a portion of a heart proximate to said esophagus; creating a three-dimensional (3-D) esophageal representation using said image; superimposing said 3-D esophageal representation onto a 3-D left atrial representation; and determining a correspondence between said 3-D esophageal representation and said 3-D left atrial representation.

14. The system of claim 13, wherein said instructions, when executed, further cause said system to perform additional operations, said additional operations comprising: dynamically updating said 3-D esophageal representation in real-time as additional image data is obtained using said sensor.

15. The system of claim 13, wherein said instructions, when executed, further cause said system to perform additional operations, said additional operations comprising: obtaining fluoroscopic image data of said esophagus enhanced with a radiocontrast agent; and validating said correspondence between said 3-D esophageal representation and said 3-D left atrial representation using said fluoroscopic image data.

16. The system of claim 15, wherein said fluoroscopic image data is generated via fluoroscopy of a duration selected from the group consisting of: five seconds or less, one second to two seconds or less, and less than one second.

17. The system of claim 13, wherein said instructions, when executed, further cause said system to perform additional operations, said additional operations comprising: obtaining an additional image of said esophagus using said sensor subsequent to said esophagus being translated from a first position to a second position distinct from said first position; updating said 3-D esophageal representation using said additional image; and determining an updated correspondence between said 3-D esophageal representation and said 3-D left atrial representation.

18. The system of claim 13, wherein obtaining said image comprises: directing ultrasonic energy towards the esophagus via a left atrium wall of said heart.

19. The system of claim 13, wherein said correspondence is a radial distance between a posterior wall of a left atrium of said heart and an anterior wall of said esophagus, a lateral position of said esophagus relative to said posterior wall of said left atrium, or a combination thereof.

20. A composition for enhancing real-time visualization of an esophagus, said composition comprising: one or more echocontrast agents and one or more viscosity agents; one or more echocontrast agents and one or more carrier solutions; one or more echocontrast agents, one or more viscosity agents and one or more carrier solutions; one or more echocontrast agents and one or more radiocontrast agents; one or more echocontrast agents, one or more radiocontrast agents and one or more carrier solutions; one or more echocontrast agents and one or more coating agents; or one or more echocontrast agents, one or more coating agents and one or more carrier solutions.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

[0013] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various embodiments of the present invention and, together with the general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the embodiments of the invention.

[0014] FIG. 1 depicts an ICE image of the posterior wall of the left atrium prior to injection of an echocontrast agent into the esophagus (see, orange oval).

[0015] FIG. 2 depicts the ICE image of the posterior wall of the left atrium of FIG. 1 and the esophagus after an echocontrast agent has been injected into the esophagus (see, orange oval).

[0016] FIG. 3 depicts an ICE image of the posterior wall of the left atrium and the esophagus after an echocontrast agent has been injected into the esophagus, wherein at least a portion of the esophagus has been traced (see, green line) to define an esophageal contour for incorporation into a CARTO anatomical map.

[0017] FIG. 4 depicts the esophageal contour defined in FIG. 3 as incorporated into the CARTO anatomical map (see, blue arrows pointing to the esophageal contour both in the ICE image and the CARTO anatomical map (oriented in a posterior-anterior view)).

[0018] FIG. 5 depicts a completed esophageal map superimposed onto a map of the posterior wall of the left atrium in the CARTO anatomical map (oriented in a posterior-anterior view) (see, blue arrow pointing to the completed esophageal map shown in light green).

[0019] FIG. 6A depicts the position of an ablation catheter shown within fluoroscopic image data of an esophagus enhanced with a radioconstrast agent (e.g., gastrograffin)), and FIG. 6B depicts the echo-contours of the esophagus (enhanced with an echocontrast agent (e.g., the DEFINITY contrast agent) on the CARTO anatomical map (in both FIGS. 6A and 6B, a blue oval encircles and identifies the ablation catheter on the right edge of the esophagus, and a blue arrow identifies the esophagus).

[0020] FIGS. 7A-7D depict alternate views of the CARTO anatomical map showing an esophageal map created using echo contours of the esophagus (see, orange arrow identifying the esophageal map in light green; and see, blue arrows identifying the approximate border of the esophagus extrapolated to the CARTO anatomical map from a fluoroscopic image of the radiocontrast enhanced esophagus of FIG. 6A, showing overall correlation between the fluoroscopic and echo-contour methods.

[0021] FIG. 8 depicts esophageal deviation shown within fluoroscopic image data (see, blue arrow identifying an EsoSure device placed into the esophagus and deviating the esophagus to the left).

[0022] FIG. 9 depicts esophageal deviation on a CARTO map, in which an echocontrast agent aids in visualization of the esophagus (see, orange arrow identifying the initial esophageal position (shown in light green), and see the blue arrow identifying the re-mapped esophagus (shown in light purple) after rightward deflection).

DETAILED DESCRIPTION OF THE INVENTION

[0023] For simplicity and illustrative purposes, the principles of the present invention are described by referring to various exemplary embodiments thereof, and which embodiments may be depicted in FIGS. 1-9. It is understood that the present invention is not limited to the particular examples, embodiments or methods described herein or otherwise depicted in the Figures, as these may vary. It is also to be understood that the terminology used herein is used for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention. Moreover, although certain methods may be described with reference to certain steps that are presented herein in a certain order, in many instances, these steps may be performed in any order as would be appreciated by one of ordinary skill in the art, and thus the methods are not limited to the particular arrangement of steps disclosed herein. It must be noted that as used herein and in the appended claims, the singular forms a, an and the include the plural reference unless the context clearly dictates otherwise.

[0024] Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. Specific methods and materials are described, although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention.

[0025] Referring now to FIGS. 1-9, the present invention is directed to compositions, methods and systems for identifying the relative positions and/or orientations (correspondences) of the esophagus with respect to the left atrium prior to and during atrial fibrillation ablation procedures. Such compositions, methods and systems may be used to avoid or reduce the incidence of AEF.

[0026] In an embodiment of the present invention, a composition comprising an echocontrast agent is introduced into the esophagus so as to enhance real-time visualization of the esophagus under intracardiac echocardiography (ICE), and thereby visually differentiate the esophageal lumen from surrounding tissue (see, e.g., FIGS. 1, 2). Under ICE, the contrast enhanced esophagus is then imaged and traced to generate a contour (see, e.g., FIG. 3) which is then incorporated into a 3-D map or digital representation of the esophagus using available 3-D mapping systems, such as the CARTO mapping system (see, e.g., FIG. 4). Multiple tracings of sequential esophageal ICE images are taken to yield esophageal contours, which, in the aggregate, will be incorporated into the CARTO mapping system for the creation of the 3-D map of the esophagus. This 3-D esophageal map, superimposed on and together with the 3-D map of the left atrium (previously imaged via ICE), is then used to visually and accurately identify the entirety of any area, or the full width of any portion, of the esophagus that lies in contact with or in near proximity to those areas of the posterior wall of the left atrium that the operator intends to ablate (see, e.g., FIG. 5). In particular, superimposing the respective 3-D maps (or representations) facilitates a determination of a correspondence between the esophagus and the left atrium. For example, superimposing the respective 3-D maps facilitates a determination of the position and/or orientation of the esophagus relative to the left atrium including, but not limited to, an assessment of the radial distance (i.e., in the spine to chest direction) of the posterior wall of the left atrium to the anterior wall of the esophagus, as well as the lateral position (i.e., in the arm-to-arm direction) of the esophagus relative to the posterior wall of the left atrium. By adding radiocontrast to the echocontrast as part of the solution injected into the esophagus (as described above), optional cross-validation of the position and/or orientation of the esophagus relative to the left atrium may be achieved by generating fluoroscopic image data via brief fluoroscopy, and by marking or annotating, on the CARTO map of the left atrium, the esophageal border as seen on the fluoroscopic image data (see, e.g., FIGS. 6A, 6B, and 7A-7D). In an embodiment, the brief fluoroscopy is for a limited duration of five seconds or less, and preferably for a limited duration of one second to two seconds or less, and more preferably for a limited duration of less than one second. Thereafter, using available esophageal deviation devices, the esophagus may be moved away from any such area of intended ablation (see, e.g., FIG. 8), and the esophagus re-imaged and re-mapped and then re-evaluated against the 3-D map of the left atrium to ensure sufficient clearance from the intended area of ablation (see, e.g., FIG. 9).

[0027] In the foregoing embodiment of the present invention, it is contemplated that the composition may alternatively comprise: one or more echocontrast agents and one or more viscosity agents; one or more echocontrast agents and one or more carrier solutions; one or more echocontrast agents, one or more viscosity agents and one or more carrier solutions; one or more echocontrast agents and one or more radiocontrast agents; one or more echocontrast agents, one or more radiocontrast agents and one or more carrier solutions; one or more echocontrast agents and one or more coating agents; or one or more echocontrast agents, one or more coating agents and one or more carrier solutions. In each such composition, the echocontrast agent, when introduced into the esophagus, serves to enhance real-time visualization of the esophagus under ICE, and thereby visually differentiate the esophageal lumen from surrounding tissue. Moreover, in each such composition, the viscosity agents, coating agents and carrier solutions serve to more effectively deliver and coat the entirety or any selected portion of the esophagus with the echocontrast agent.

[0028] In the foregoing embodiment of the present invention, the echocontrast agent that may be used in the several described compositions includes, for exemplary purposes only, the DEFINITY contrast agent (available from Lantheus Medical Imaging) and/or the OPTISON contrast agent (available from GE Healthcare). The DEFINITY contrast agent is an injectable ultrasound contrast agent comprised of lipid-coated echogenic microbubbles filled with octafluoropropane gas, and the OPTISON contrast agent is a sterile non-pyrogenic suspension of microspheres of human serum albumin with perflutren (i.e., perflutren protein-type A microspheres injectable suspension, USP)). With either of these contrast agents, the microbubbles (in DEFINITY) and the microspheres (in OPTISON) create an echogenic contrast effect in the blood. Specifically, the acoustic impedance of the microbubbles/microspheres is much lower than that of the blood. Therefore, impinging ultrasound waves are scattered and reflected at the microbubble/microsphere-blood interface and ultimately may be visualized in the ultrasound image. At the frequencies used in adult echocardiography (2-5 MHz), the microbubble/microspheres resonate which further increases the extent of ultrasound scattering and reflection. The viscosity or coating agent(s) that may be used in the several described compositions include, for exemplary purposes only, one or more of gastrograffin (a radiocontrast agent), sucralfate, barium sulfate, or polyethylene glycol solution. The carrier solution(s) that may be used in the several described compositions include, for exemplary purposes only, one or more of saline, water with dextrose or thickening agent, or other agent to slow motility through the esophagus and coat the esophagus. In the event any one of the several described compositions uses a radiocontrast agent (e.g., gastrograffin) as a viscosity agent, such radiocontrast agent optionally provides the operator with the ability to view the esophagus as a 2-D structure under fluoroscopy, whether prior to or during the ablation procedure, and to thus receive additional details pertaining to the location and orientation of the esophagus.

[0029] In another embodiment of the present invention, a composition comprising the DEFINITY contrast agent (an echocontrast agent), gastrograffin (a radiocontrast agent serving as a viscosity agent) and saline (as a carrier agent), is introduced into the esophagus so as to enhance real-time visualization of the esophagus under intracardiac echocardiography (ICE), and thereby visually differentiate the esophageal lumen from surrounding tissue (see, e.g., FIGS. 1, 2). Under ICE, the contrast enhanced esophagus is then imaged and traced to generate a contour (see, e.g., FIG. 3) which is then incorporated into a 3-D map or digital representation of the esophagus using available 3-D mapping systems, such as the CARTO mapping system (see, e.g., FIG. 4). Multiple tracings of sequential esophageal ICE images are taken to yield esophageal contours, which, in the aggregate, will be incorporated into the CARTO mapping system for the creation of the 3-D map of the esophagus. This 3-D esophageal map, superimposed on and together with the 3-D map of the left atrium (previously imaged via ICE), is then used to visually and accurately identify the entirety of any area, or the full width of any portion, of the esophagus that lies in contact with or in near proximity to those areas of the posterior wall of the left atrium that the operator intends to ablate (see, e.g., FIG. 5). In particular, superimposing the respective 3-D maps (or representations) facilitates a determination of a correspondence between the esophagus and the left atrium. For example, superimposing the respective 3-D maps facilitates a determination of the position and/or orientation of the esophagus relative to the left atrium including, but not limited to, an assessment of the radial distance (i.e., in the spine to chest direction) of the posterior wall of the left atrium to the anterior wall of the esophagus, as well as the lateral position (i.e., in the arm-to-arm direction) of the esophagus relative to the posterior wall of the left atrium.

[0030] Additionally, in the foregoing embodiment, use of a radiocontrast agent as a viscosity agent in the composition (described above) optionally provides the operator with the ability to view the esophagus as a 2-D structure depicted within fluoroscopic image data generated via brief fluoroscopy, and wherein cross-validation of the position and/or orientation of the esophagus relative to the left atrium may be achieved by marking or annotating, on the CARTO map of the left atrium, the esophageal border as seen on the fluoroscopic image data (see, e.g., FIGS. 6A, 6B, and 7A-7D). In an embodiment, the brief fluoroscopy is for a limited duration of five seconds or less, and preferably for a limited duration of one second to two seconds or less, and more preferably for a limited duration of less than one second. Thereafter, using available esophageal deviation devices, the esophagus may be moved away from any such area of intended ablation (see, e.g., FIG. 8), and the esophagus re-imaged and re-mapped and then re-evaluated against the 3-D map of the left atrium to ensure sufficient clearance from the intended area of ablation (see, e.g., FIG. 9). In the foregoing embodiment, use of the radiocontrast agent gastrograffin as a viscosity agent in the composition, optionally provides the operator with the ability to view the esophagus as a 2-D structure under fluoroscopy, whether prior to or during the ablation procedure, and to thus receive additional details pertaining to the location and orientation of the esophagus.

[0031] In yet another embodiment of the present invention, a composition comprising 5 cc of the DEFINITY contrast agent (an echocontrast agent), 10 cc of gastrograffin (a radiocontrast agent serving as a viscosity agent) and 5 cc of saline (as a carrier agent), is prepared for introduction into the (mid) esophagus (again, for purposes of enhancing visualization of the esophagus under intracardiac echocardiography (ICE), and thereby visually differentiating the esophageal lumen from surrounding tissue) (see, e.g., FIGS. 1, 2). Specifically, the composition is prepared by first mixing 5 cc of the DEFINITY contrast agent with 5 cc of saline (medium), with that mixture then being drawn into a syringe containing 10 cc of gastrograffin and thus admixed therewith. A standard orogastric tube (e.g., as available from Bard Medical) is advanced through the esophagus and into the stomach of the patient, with gastric contents returned to eliminate the possibility of tracheal placement. The tube is generally pulled back to about 35 cm at the lips, which generally places the open ports of the orogastric tube at the middle portion of the cardiac silhouettea position that may be verified with brief fluoroscopy in view of radiolucent markers on the orogastric tube. In an embodiment, the brief fluoroscopy is for a limited duration of five seconds or less, and preferably for a limited duration of one second to two seconds or less, and more preferably for a limited duration of less than one second. This brief visualization also identifies the general position of the esophagus; that is, whether the esophagus is more prone to the left or right side of the cardiac silhouette. The composition (contained in the syringe) is then injected into the orogastric tube, the end of which tube is held several feet above the level of the supine patient so as to encourage the composition to flow down into the esophagus. The composition may generally take about 30 seconds to completely coat the esophagus. Once coated with the composition, the contrast enhanced esophagus is then imaged under ICE and mapped (using available 3-D mapping systems, such as the CARTO mapping system) to generate a 3-D map or digital representation of the esophagus, thereby identifying any critical or relevant area of the esophagusi.e., any area of the esophagus that lies in contact with or in near proximity to those areas of the posterior wall of the left atrium (previously imaged via ICE) that the operator intends to ablate (see, e.g., FIGS. 3, 4).

[0032] With specific regard to this imaging process, if the esophagus is closer to the right pulmonary veins, the esophagus is best identified via ICE with the catheter placed in the mid-right atrium. If, however, the esophagus is closer to the left pulmonary veins, the ICE catheter may be deflected into the right ventricular outflow tract, and then rotated clockwise until the esophagus can be visualized via ICE. In either case, with the ICE catheter positioned or otherwise generally directed toward the esophageal structure, and using the CARTO mapping system, the image of the contrast enhanced esophagus can be mapped or traced along the posterior wall of the left atrium to generate sequential contours, which, in the aggregate, are used to create a 3-D map of the esophagus, which is then added to the left atrial map (again, the left atrium having been previously imaged via ICE) (see, e.g., FIGS. 1-4). This 3-D esophageal map, superimposed on and together with the 3-D left atrial map, is then used to visually and accurately identify the entirety of any area, or the full width of any portion, of the esophagus that lies in contact with or in near proximity to those areas of the posterior wall of the left atrium that the operator intends to ablate (see, e.g., FIG. 5). In particular, superimposing the respective 3-D maps (or representations) facilitates a determination of a correspondence between the esophagus and the left atrium. For example, superimposing the respective 3-D maps facilitates a determination of the position and/or orientation of the esophagus relative to the left atrium including, but not limited to, an assessment of the radial distance (i.e., in the spine to chest direction) of the posterior wall of the left atrium to the anterior wall of the esophagus, as well as the lateral position (i.e., in the arm-to-arm direction) of the esophagus relative to the posterior wall of the left atrium. It is contemplated herein that the foregoing composition may be used in any automatic mapping process that (simultaneously or near simultaneously) maps the esophagus during mapping of the left atrium, and wherein the computer mapping system would identify the contrast enhanced esophageal segments and automatically generate a 3-D map of the esophagus superimposed on the 3-D left atrial map.

[0033] Following this mapping process, and thus upon determining the position and/or orientation of the esophagus relative to the posterior wall of the left atrium, the esophagus may be moved away from any area of intended ablation (e.g., translated from a first position to a second position that is distinct from the first position) using available esophageal deviation devices (see, e.g., FIG. 8), and the esophagus re-imaged and re-mapped and then re-evaluated against the left atrial map to ensure sufficient clearance from the intended area of ablation. In particular, the trailing edge (and, optionally the leading edge) of the esophagus is re-imaged and re-mapped to ensure that the esophagus is no longer in contact with or in near proximity to any area of the posterior wall of the left atrium that the operator intends to ablate (see, e.g., FIG. 9). Esophageal deviation devices may include, for example, the EsoSure esophageal retratactor (available from EPreward, Inc.), or any other physical instrument(s) that clear or move the esophagus away from the posterior wall of the left atrium both prior to and during the ablation procedure (that is, deviate the esophagus such that the posterior wall of the left atrium is no longer in contact therewith or in near proximity thereto). Additionally, in the foregoing embodiment, use of a radiocontrast agent, such as gastrograffin, as a viscosity agent in the composition optionally provides the operator with the ability to view the esophagus as a 2-D structure under fluoroscopy, and wherein cross-validation of the position and/or orientation of the esophagus may be achieved by marking or annotating, on the CARTO map of the left atrium, the esophageal border as seen on fluoroscopy during either the initial mapping or re-mapping processes described hereinabove (see, e.g., FIGS. 6A, 6B, and 7A-7D).

[0034] It is contemplated herein that, while certain aspects of the foregoing systems and methods may use fluoroscopy (for instance, at the initial stages of inserting and positioning the orogastric tube prior to injection of the composition, as described above), the present systems and methods may entirely dispense with fluoroscopy through use of improved orogastric tube designs. For example, an orogastric tube, with integral channels through which sensor-based or electrode-based catheters may be fed, would be visible under ICE, thus entirely dispensing with any fluoroscopy, whether at the afore-described initial stages of inserting and positioning the orogastric tube, or otherwise. Moreover, to facilitate a contrast enhanced esophageal visualization throughout the ablation procedure, an improved orogastric tube design with one or more exit holes on the side of the tube would allow for multiple injections of contrast agent, whether prior to or subsequent to esophageal deviation, so as to respond to any contrast agent prematurely draining into the stomach.

[0035] In each of the embodiments described herein, it is contemplated that catheter-based contact mapping may be used in addition to, or as an alternative to, 3-D mapping of the left atrium derived from ICE-based images. Moreover, 3-D mapping systems for cardiac ablation other than CARTO mapping may be developed in the future that incorporate ultrasound-based 3-D mapping that would be able to incorporate the aforementioned techniques to enhance esophageal visualization and incorporation into an anatomical map.

[0036] Upon completion of the ablation procedure, the esophageal deviation device, if used, is removed, and the orogastric tube is removed from the stomach through the esophagus under continuous suction to remove any residual composition to minimize the possibility of aspiration during extubation and recovery.

[0037] As described herein, compositions of the present invention may be formulated to include a contrast agent, a viscosity or coating agent, and a carrier agent, which, collectively, function to deliver and coat the esophagus. As such, alternate compositions may include: 5 cc of the DEFINITY contrast agent (as the echocontrast agent), 10 cc of sucralfate solution (as a viscosity agent) and 5 cc of saline (as a carrier agent); 5 cc of the DEFINITY contrast agent (as the echocontrast agent), 10 cc of barium sulfate (as a viscosity agent) and 5 cc of saline (as a carrier agent); and, 5 cc of the DEFINITY contrast agent (as the echocontrast agent), 10 cc of polyethylene glycol solution (as a viscosity agent) and 5 cc of saline (as a carrier agent).

[0038] As described herein, a method for implementing the present invention may include introducing a composition into an esophagus. An image of the esophagus is obtained using a sensor disposed within a portion of a heart proximate to the esophagus. A three-dimensional (3-D) esophageal representation is created using the image. The 3-D esophageal representation is superimposed onto a 3-D left atrial representation. A correspondence is determined between the 3-D esophageal representation and the 3-D left atrial representation. In an embodiment, the composition comprises an echocontrast agent. In an embodiment, the composition further comprises a radiocontrast agent. In an embodiment, generating the 3-D esophageal representation comprises tracing at least a portion of the esophagus within the image to define an esophageal contour. In an embodiment, the correspondence is a radial distance between a posterior wall of the left atrium of the heart and the anterior wall of the esophagus, a lateral position of the esophagus relative to the posterior wall of the left atrium, or a combination thereof. In an embodiment, obtaining the image comprises directing ultrasonic energy towards the esophagus via the left atrium wall of the heart. In an embodiment, the composition comprises: one or more echocontrast agents and one or more viscosity agents; one or more echocontrast agents and one or more carrier solutions; one or more echocontrast agents, one or more viscosity agents and one or more carrier solutions; one or more echocontrast agents and one or more radiocontrast agents; one or more echocontrast agents, one or more radiocontrast agents and one or more carrier solutions; one or more echocontrast agents and one or more coating agents; or one or more echocontrast agents, one or more coating agents and one or more carrier solutions.

[0039] In an embodiment, the method further includes introducing a radiocontrast agent into the esophagus, and obtaining a fluoroscopic image of the esophagus. In an embodiment, the method further includes obtaining an additional image of the esophagus using the sensor subsequent to the esophagus being translated from a first position to a second position distinct from the first position, updating the 3-D esophageal representation using the additional image, and determining an updated correspondence between the 3-D esophageal representation and the 3-D left atrial representation. In an embodiment, the method further includes dynamically updating the 3-D esophageal representation in real-time as additional image data is obtained using the sensor. In an embodiment, the method further includes obtaining fluoroscopic image data of the esophagus enhanced with a radiocontrast agent, and validating the correspondence between the 3-D esophageal representation and the 3-D left atrial representation using the fluoroscopic image data. In an embodiment, the fluoroscopic image data is generated via fluoroscopy of a limited duration. In an embodiment, the limited duration is of five seconds or less, and preferably of one second to two seconds or less, and more preferably less than one second.

[0040] As described herein, a system for implementing the present invention may include a sensor, a processor, and a computer-readable storage medium comprising instructions. Upon execution by the processor, the instructions cause the system to perform operations. The operations include obtaining an image of an esophagus injected with a composition while the sensor is disposed within a portion of a heart proximate to the esophagus. A three-dimensional (3-D) esophageal representation is created using the image. The 3-D esophageal representation is superimposed onto a 3-D left atrial representation. A correspondence is determined between the 3-D esophageal representation and the 3-D left atrial representation. In an embodiment, obtaining the image comprises directing ultrasonic energy towards the esophagus via the left atrium wall of the heart. In an embodiment, the correspondence is a radial distance between a posterior wall of the left atrium of the heart and the anterior wall of the esophagus, a lateral position of the esophagus relative to the posterior wall of the left atrium, or a combination thereof.

[0041] In an embodiment, the instructions, when executed, further cause the system to perform additional operations comprising dynamically updating the 3-D esophageal representation in real-time as additional image data is obtained using the sensor. In an embodiment, the instructions, when executed, further cause the system to perform additional operations comprising obtaining fluoroscopic image data of the esophagus enhanced with a radiocontrast agent, and validating the correspondence between the 3-D esophageal representation and the 3-D left atrial representation using the fluoroscopic image data. In an embodiment, the fluoroscopic image data is generated via fluoroscopy of a limited duration. In an embodiment, the limited duration is of five seconds or less, and preferably of one second to two seconds or less, and more preferably less than one second. In an embodiment, the instructions, when executed, further cause the system to perform additional operations comprising obtaining an additional image of the esophagus using the sensor subsequent to the esophagus being translated from a first position to a second position distinct from the first position, updating the 3-D esophageal representation using the additional image, and determining an updated correspondence between the 3-D esophageal representation and the 3-D left atrial representation.

[0042] While the invention has been described with reference to certain exemplary embodiments thereof, those skilled in the art may make various modifications to the described embodiments of the invention without departing from the scope of the invention. The terms and descriptions used herein are set forth by way of illustration only and not meant as limitations. In particular, although the present invention has been described by way of examples, a variety of structures and processes would practice the inventive concepts described herein. Although the invention has been described and disclosed in various terms and certain embodiments, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved, especially as they fall within the breadth and scope of the claims here appended. Those skilled in the art will recognize that these and other variations are possible within the scope of the invention as defined in the following claims and their equivalents.