Establishment of teaching and training model for transesophageal echocardiography based on swine

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Although, existing TEE simulators have become increasingly sophisticated, the use of animal models retains significant advantages in terms of enabling dynamic cardiac monitoring. The aim of this study is to develop a better teaching and training program for TEE and establish baseline values for the porcine animal model. The thorough TEE examinations were conducted in 10 domestic porcine weighing 45-60kg according to ASA guideline for TEE. All the recommended views were explored and saved. The depth and angles of each view were recorded. Additionally, hemodynamic measurements were performed and recorded. All parameters were compared with human reference values. The porcine model is feasible to initiate a teaching model, and TEE baseline values were acquired for more development in the experimental porcine model. Health sciences/Anatomy Health sciences/Diseases transesophageal echocardiography animal model education Figures Figure 1 Figure 2 Figure 3 Figure 4 Short outline Previous research on the porcine model of TEE mainly focused on applications related to surgical treatment, while also lacking a comprehensive and detailed teaching and training of TEE porcine models. Our research endeavors to devise an advanced teaching and training protocol for TEE, while also establishing comprehensive baseline data for pig animal models. These baseline values will serve as a pivotal framework for the development of anatomically and pathophysiologically accurate pig heart models, utilizing the modality of echocardiography, in forthcoming investigations.The utilization of TEE animal models offers both simulated and real-time value, closely mirroring clinical scenarios. Clinicians can effectively acquire TEE simulation training through these animal models, thereby compensating for any limitations of electronic training models. Introduction Transesophageal echocardiography (TEE) is an effective monitoring tool for use during cardiac and noncardiac surgeries perioperatively. In an increasing number of clinical scenarios, TEE plays a significant role in various surgical procedures. However, TEE education programs in China primarily rely on simulation system and in-hospital patients. Some research has already focused on the ethics of practice in the operating room, which is one of the most important teaching and training, although there are some drawbacks and controversies. Nevertheless, due to economic constraints and ethical concerns [1] , an optimal live model for TEE teaching and training has yet to be established. It is crucial to cultivate more qualified clinical anesthesiologists, particularly cardiovascular anesthesiologists, and ultrasonologists to improve the standard of care [2] . Due to the similarity in anatomy and structure between the hearts and vessels of domestic porcine and humans, domestic porcine have been extensively used as animal models in cardiovascular research, including studies on cardiovascular diseases and therapies like transcatheter therapies, cardiopulmonary resuscitation and acute myocardial infarction. Previous studies have investigated porcine models of TEE; however, they have primarily focused on the applications related to surgical treatment. Meanwhile, a comprehensive and detailed teaching and training porcine model for TEE is still lacking. Therefore, the objective of our study is to develop an enhanced teaching and training program for TEE and establish baseline values for the porcine animal model. These baseline values can serve as foundations for creating anatomical and pathophysiological porcine cardiac models using echocardiography in future studies.In addition, our simulation training using animal models aims to facilitate the rapid acquisition of manipulative techniques for obtaining echocardiographic views, thus enabling clinicians participating in the training program to enhance their proficiency. Materials and Methods Animals Ten healthy domestic porcine aged 12–18 months and weighing between 45-60kg were selected for this study. All the animal experiments were approved by the Animal Ethical Committee of Nanjing First Hospital, Nanjing Medical University, and all of the experiments were conducted in accordance with National Regulations on the Administration of Laboratory Animals. Prior to the experiment, the animals should abstain from eating and drinking for at least 8 hours. All the porcine received a intramuscular injection of midazolam (0.5 mg/kg) and ketamine (10mg/kg) for anesthesia induction. Subsequently,, the porcine were positioned in the right lateral position on the operating table, with all four limbs secured. This positioning provides optimal access to the heart images in the porcine model. Following vein access which was established through the auricular vein using a 22G intravenous catheter, general anesthesia was inducted by administering a bolus injection of propofol (0.5-1mg/kg) and remifentanil (1–2µg/kg) intravenously and the endotracheal intubation (size 6.0 F, for porcine of 45-60kg) was conducted when the postural and eyelash reflexes disappeared, and spontaneous breathing was retained during the induction. Mechanical ventilation mode was delivered in the form of intermittent positive pressure ventilation (IPPV) with the tidal volume being 6–8 ml/kg, ventilation frequency 15 bpm, I/E 1:2. General anesthesia was maintained by intravenous and inhalation methods, and the combined anesthesia was administered with 2–3% of sevoflurane in 100% oxygen concentration (oxygen flow 2L/min) and intravenous infusion of propofoll (2 mg/kg/h) and remifentanil(0.2 µg/kg/min) continuously. During the experiment, hydroxyethyl starch and saline were administered intravenously to meet physiological requirements. Continuous five-lead electrocardiogram (ECG) monitoring, SpO 2 through the skin sensor and invasive pressure measurements were conducted for basic hemodynamic monitoring. Transesophageal Echocardiography Following the induction of anesthesia, ensure the TEE probe was at neutral position and flexible, then the TEE probe was inserted into the oropharynx and advanced to the mid-esophagus using a laryngoscope for guidance(schematic diagram of TEE probe position in porcine esophagus, Fig. 1 ). To protect the TEE probe, a bite block and a roll of bandages were positioned in the mouth at an appropriate location. Establish a connection between the porcine and the 5-lead ECG on the echocardiography machine to obtain a continuous electrocardiographic signal. Mechanical ventilation was temporarily paused when ultrasound images were acquired. Starting from a mid-esophageal position, the thorough and comprehensive TEE examination was performed by an experienced cardiovascular anesthesiologist according to a clinical guideline [3] . One empirical anesthesiologist was responsible for anesthesia management and monitoring the vital signs, and another researcher was responsible for recording. The examination was started at around 45–48 cm from the maxillary incisors. In the mid-esophagus, the probe was gradually adjusted in a clockwise direction and anteflected. Adjusting the transducer angle to approximately 0–10° enabled more specific imaging. The ME four-chamber view indicated the left atrium, right atrium, Left ventricle (LV), right ventricle (RV), mitral valve (MV), and Tricuspid valve (TV),.However, the quality of the right atrium and right ventricle imaging was slightly subpar, and the tricuspid valve did not appear clearly due to the difference of location of the main bronchus between porcine and humans. Based on ME 4C view, the flexion of the tip of the probe and the rotation of the transducer were adjusted continuously to obtain optimal two-dimensional ultrasound images of the heart chamber, walls and valves in the approaching middle-segment of the esophagus. From the mid-esophagus position, the probe was rotated to the left with angles manipulated to 0–10 ° to obtain the short-axis (SAX) and long-axis (LAX) view of the descending aorta. Then, the probe was carefully withdrawn to obtain imaging of the aorta in the upper esophagus, including the aortic arch and the ascending aorta.. Upon visualizing the aortic arch, the modified views of the left and right ventricular outflow tracts became visible. These views can be utilized to measure cardiac output (inset). Subsequently, the probe was advanced slowly in search of transgastric views. However, in the porcine model, no additional transgastric views beyond the transgastric hepatic vein and inferior vena cava (IVC) view were obtainable. Furthermore, measurements of cardiac chamber and valve diameters were obtained. Assessment of left and right heart function was performed, along with measurement and analysis of valve function and blood flow. The specific manipulating means were as follows: ( 1 ) ME 4-C view was obtained at the mid-esophageal level. Optimized images were obtained by manipulating the probe, involving anteflexion, right rotation, and left lateriflexion in the range of angles from 0–15°.. Once the standard ME 4-C view was established, adjusting the angles of the plane allowed for visualization of different views. ( 2 ) With right rotation of the probe,, the ME 2-C view was obtained at angles ranging from 35–60°.Additionally, at angles between 70–100°, the long-axis view, which is also a three-chamber (3-C) view, could be visualized. ( 3 ) In order to observe the structure and function of the mitral valve at the mid-esophageal level, the angle of the probe was adjusted to 35–50° and the probe was flexed anteriorly to obtain a mitral commissural view. ( 4 ) Moreover, a clear visualization of the left atrial appendage view was achieved by anteflexing the probe at angles ranging from 30–60°. ( 5 ) In the porcine model, obtaining the ME 5-C view proved to be more challenging when withdrawing the probe and applying anteflexion from the ME 4-C heart view ( 6 ) The left and right pulmonary vein views were difficult to visualize even in humans. At the mid-esophageal level, the probe was adjusted for anteflexion and right rotation, and then, the left and right pulmonary vein views could be achieved at 30–50° and 100–120° respectively, and color Doppler was usually needed to assist in determining the acquisition of pulmonary veins. ( 7 ) At the mid-esophagus, other views could be acquired. From the long-axis view described in the preamble, advancing the probe could get the aortic valve LAX view when the aortic valve was put in the center of the frame with the angle range of 70–100°, and the aortic valve SAX view could be obtained at the angle of 30–50°. I Withdrawing the probe and adjusting the angle to 0–50°, the ascending aorta SAX view can be acquired in the anteflexion position. The ascending aorta long-axis (LAX) view is obtained within the angle range of 70–90°. ( 8 ) By anteflexing and right-rotating the probe, the RV inflow-outflow view can be obtained from the aortic valve SAX view, within the angle range of 20–60°. However, this view may result in shadowing of the pulmonary valve and tricuspid valve. Alternatively, the biatrial view can be acquired at an angle of 60–100°..( 9 ) In instances where a more detailed assessment of the tricuspid valve was necessary, the probe can be flexed at an angle of 90–120°. This maneuver, referred to as a modified biaxial TV view, enables visualization of both the left and right atria.. ( 10 ) To visualize the great vessels, views at the level of the upper esophagus were indispensable. ( 11 ) Generally, the descending aorta short-axis (SAX) view is acquired by withdrawing and rotating the probe to the left, maintaining an angle of 0° from the mid-esophageal four-chamber (ME 4-C) view. Subsequently, adjusting the angle to 80–90° allows for visualization of the descending aorta long-axis (LAX) view. ( 12 ) After acquiring the descending aortic SAX view, the probe is consistently withdrawn until the aortic arch is visualized. Subsequently, adjusting the angle to 60–90° facilitates obtaining the aortic arch long-axis (LAX) view. ( 13 ) Notably, at the aortic arch LAX view, a modified Left ventricular outflow tract (LVOT) view could be obtained. This enables the measurement of LVOT diameter and subsequent calculation of cardiac output (CO). In some cases of porcine, the pulmonary valve LAX and right cardiac outflow tract can be seen simultaneously. ( 14 ) Due to the special anatomical structures of the porcine, all the transgastric short axis views of LV and RV were not obtained in the porcine model, only inferior vena cava(IVC) and hepatic vein(HPV) were found and shown when we probed the depth of the stomach at the angle of 60–70° with the anteflexion and right rotation of the probe. The images of various views can be seen in Fig. 2 – 4 . To evaluate TEE image quality [4] TEE conditions in the swine model were evaluated and graded as follows: Excellent: All structures are visualized with clear contours and can be easily identified. Good: Structures are mostly of good contrast (distinct) and can be identified. Poor: Visualization of structures is possible to only a limited degree. Evaluation of parameters is limited. Not Possible: Visualization of structures is not possible even in different views, and evaluation or guidance cannot be conducted. Statistical analysis This study is an exploratory and observational research. All data were reorganized and inputted into an Excel spreadsheet (Version 2016, Microsoft), and statistical analysis was performed using the SPSS 20.0 (IBM). Descriptive statistics were conducted as appropriate according to the characteristics of the data. Continuous variables with normal distribution were expressed as the mean ± standard deviation ( x̄±s ), while categorical data were expressed as numbers and rates. A P -value of < 0.05 was considered to indicate statistically significant. Results Procedures of anesthesia and insertion of the probe in all ten porcine were practicable. We completed the exploration of all views, and most of the middle and upper esophageal views could be displayed, but none of the transgastric views of LV and RV could be obtained. Similarly, the measured parameters were obtained. Although all the porcine were healthy, one swine presented with an atrial septal defect and another was diagnosed with moderate aortic valve regurgitation. We conducted a comprehensive TEE examination, thoroughly examining all relevant details. According to recent research [5] , it is important to note that the anatomy of a porcine differs from that of a human. The main bronchus of porcine is situated between esophagus and heart. Specific recommendations for depth and transducer angles were presented in Table 1 . Table 2 provides an overview of the anatomical and functional parameters of the porcine heart, encompassing measurements of left and right ventricular dimensions and function, aortic root and aortic dimensions, and functional parameters for all four valves. Table 1 The basic values of TEE images in porcine (n = 10, x̄±s) View Swine Human [3] Maneuver Angle (degree) Depth (cm) Angle (degree) 1 ME four-chamber view 0–15° 44.7 ± 4.8 0–10° Anteflexion, right rotation and left lateriflexion 2 ME two-chamber view 35–60° 44.7 ± 4.8 80–100° Right rotation 3 ME Long axis view 70–100° 45.5 ± 3.9 120–140° Right rotation 4 ME Ascending aorta-LAX view 50–90° 43.4 ± 5.7 90–110° Anteflexion 5 ME Ascending aorta-SAX view 0–50° 44.7 ± 5.2 0–30° Anteflexion 6 ME AV LAX view 70–100° 46.3 ± 4.7 120–140° Anteflexion and right rotation 7 ME AV SAX view 30–50° 46.5 ± 3.6 25–45° Anteflexion and right rotation 8 ME RV inflow-outflow view 20–60° 46.2 ± 3.5 50–70° Anteflexion and right rotation 9 ME Biatrial view 60–100° 46.4 ± 3.8 90–110° Anteflexion and right rotation 10 ME Five-chamber view 0° 44.5 ± 2.1 0–10° Anteflexion 11 ME Mitral commissural view 35–50° 45.1 ± 4.1 50–70° Anteflexion 12 ME Right pulmonary vein view 100–120° 46.2 ± 4.5 90–110° Right rotation 13 ME Modified biatrial TV view 90–120° 46.5 ± 4.0 50–70° Anteflexion and right rotation 14 ME Left pulmonary vein view 30–65° 46.9 ± 4.7 0–30° Anteflexion 15 ME Left atrial appendage view 30–60° 46.2 ± 3.7 30–60° Anteflexion and left rotation 16 UE Aortic arch LAX view 0° 38.9 ± 3.1 0–10° Neutral position 17 UE Aortic arch SAX view 60–90° 38.9 ± 3.1 70–90° Neutral position 18 ME Descending aorta SAX view 0° 45.5 ± 3.8 0–10° Neutral position 19 ME Descending aorta LAX view 80–90° 45.2 ± 4.0 90–100° Neutral position 20 UE Modified LVOT view 0° 38.9 ± 3.1 100–130°(ME) Neutral position 21 TG HPV view 60–75° 56.7 ± 2.3 / Anteflexion 22 TG IVC view 50–75° 56.7 ± 2.3 / Anteflexion Table 2 The values of anatomic and functional parameters of heart in porcine(n = 10, x̄±s ) Parameters Values LV function LVESd (mm) 21.87 ± 4.46 LVEDd(mm) 36.67 ± 4.50 LVESV(ml) 14.20 ± 5.84 LVEDV(ml) 46.84 ± 16.59 LVEF(%) 69.33 ± 6.94 SV(ml) 56.34 ± 14.26 CO(ml/min) 4.05 ± 0.95 Aorta valve and aorta Aortic annulus diameter(mm) 19.09 ± 2.15 Sinus of Valsalva diameter (mm) 24.33 ± 6.14 Sinotubular junction diameter (mm) 21.91 ± 7.39 Ascending aorta diameter(mm) 20.49 ± 2.84 Descending aorta diameter (mm) 14.27 ± 5.05 Max. jet velocity aortic valve (cm/s) 125.22 ± 16.51 Max.PG AV (mmHg) 6.37 ± 1.67 Mean PG AV (mmHg) 2.82 ± 0.47 Mitral valve Mitral valve diameter ap(mm) 16.76 ± 14.74 Mitral valve diameter cc(mm) 9.85 ± 9.12 Effective area of mitral orifice (cm 2 ) 3.66 ± 0.63 Transmitral peak early(E wave) velocity (cm/s) 79.59 ± 14.01 Max.gradient of E wave velocity (mmHg) 2.60 ± 1.02 Mean gradient of E wave velocity (mmHg) 1.32 ± 0.52 RV function FAC (%) 49.25 ± 7.16 TAPSE (cm) 1.74 ± 0.21 Tricuspid valve Transtricuspid peak early(E wave) velocity (cm/s) 56.2 ± 9.1 Max.gradient of E wave velocity (mmHg) 1.30 ± 0.42 Mean gradient of E wave velocity (mmHg) 1.33 ± 1.68 Pulmonary valve Max jet velocity of pulmonary valve (cm/s) 82.96 ± 26.68 Max gradient of pulmonary valve (mmHg) 3.04 ± 2.11 Mean gradient of pulmonary valve (mmHg) 1.27 ± 0.82 Note: TAPSE (tricuspid annular plane systolic excursion); FAC (fractional area change); Max.PG AV (maximum pressure gradient of blood flow through aortic valve); Mean PG AV (mean pressure gradient of blood flow through aortic valve). Discussion Swine have increasingly been utilized in various cardiovascular pathophysiological models, including pulmonary artery regurgitation [6] , hemorrhagic shock model [7] , transcatheter therapies model [8–10] , cardiopulmonary resuscitation model [11] , etc.. Researchers have employed TEE as a valuable tool to effectively assess cardiovascular structures and function in porcine. Previous studies have investigated the porcine model of TEE [4,5] , but none have provided such detailed exploration as this study. Additionally, data on porcine models of TEE remain limited. Consequently, we proceeded to investigate the baseline values of cardiac ultrasound images based on TEE in swine from anatomical structure, valve function and hemodynamic monitoring. Theses findings not only support the development of a simulated physiological cardiac TEE teaching model, but also provide a foundation for future studies involving pathological and therapeutic models. Presently, TEE training in China predominantly relies on e-learning through echocardiography simulation systems and clinical training in the operating room. However, intraoperative TEE has evolved to non-cardiac surgery and out-operating room monitoring, which diminishes the training opportunities of TEE in many medical centers. While the CAE Vimedix Simulator, a perioperative transesophageal echocardiography simulator,provides valuable training for basic image interpretation [12] , cost constraints prevent certain medical institutions in China from acquiring such resources. Furthermore, the aforementioned training primarily focuses on basic images depicting anatomical and physiological conditions, rather than encompassing pathological models. Nevertheless, utilizing an animal ultrasound model offers a more realistic representation of the clinical setting. To achieve optimal image quality, we experimented with various positions during the examination and eventually set the position of porcine in the right lateral-recumbency as it proved to be more advantageous than supine or the left lateral-recumbency. It is of a great possibility that the heart is closer to the esophagus due to the gravity in the right lateral-recumbency, which facilitated the acquisition of ultrasound images and improved the image quality. In a similar study, healthy dogs had minor stroke volume and LVET (left ventricular ejection time) in the supine position compared to that in left and right lateral-recumbency, but other parameters showed no significant difference. While our study primarily focused on establishing clear and practical images and baseline values, we did not extensively investigate the impact of various positions. In addition, transthoracic echocardiography(TTE) was also conducted in the meantime, and the short-axis image of LV and RV based TTE can compensate for the absence of transgastric TEE images, but it was not the main purpose of the current research, which will not be elaborated here. Swine, belonging to the artiodactyla family, exhibit cardiac and vascular structures that are similar to those of humans. Due to the special location of the main bronchus and stomach, it was impossible to detect some cavities that are easy to find in human, like transgastric section. Furthermore, the deep transgastric view holds significant importance in measuring cardiac output within the left ventricular outflow tract. Although due to anatomical limitations, we were unable to obtain a good gastric basal short-axis view, which would provide us with the same kind of CO measurements as in the human body, we were able to identify a modified view in the upper esophageal region that can serve as an alternative for calculating CO. Porcine weighing between 45-60kg, which were included in this study, possess heart structures that exhibit a high degree of similarity to human hearts.. These studied porcine demonstrated notable similarities in terms of cardiac chambers, walls, valve function, heart function, and even cardiac output. Interestingly, the measured cardiac output in porcine was reported to be higher than that in humans, as assessed through tissue Doppler imaging [13] . However, in the RT-3D TEE imaging examination, we found that the angles and orientations of the mitral and aortic valves were different from those of humans anatomically, that between the mitral valve plane and the aortic annulus was found to be about 80° (median number) in porcine. It should be noted that sternotomy was not performed in our study to validate the data concerning the heart chambers and walls acquired through TEE. In conclusion, performing transesophageal echocardiography in pigs yields replicable and comparable results to that in humans, highlighting the feasibility of implementing a teaching model. Utilizing the animal model allows clinicians to receive effective simulation training in TEE, thereby addressing the limitations of electronic training models. The key advantage lies in the simulation and real-time applicability of TEE animal models, which closely resemble clinical scenarios. In this study, TEE baseline values were acquired, providing a foundation for further development of the experimental porcine model. However, this study has certain limitations. In this study, we only focused on acquiring basic anatomical and physiological values of the transesophageal echocardiography (TEE) model and did not establish certain pathological models, which will be the main direction of further research. Conclusion Conclusively, the conduction of transesophageal echocardiography in porcine is replicable and similar to humans’, for that it’s feasible to initiate a teaching model. Clinicians could get effective TEE simulation training through the animal model to make up for the deficiency of the electronic training model. The key is the simulation and real-time value of TEE animal models, which are more closely related to clinical situations.TEE baseline values were acquired for more development in the experimental porcine model. Declarations The authors confirm that the study is reported in accordance with ARRIVE guidelines. Data Availability The datasets used and/or analysed during the current study available from the corresponding author on reasonable request. All data generated or analysed during this study are included in this published article [and its supplementary information files]. Funding Nanjing GaoFeng Talent Project (YY-104 to LC). Nanjing Health Youth Talent Training Project (Level 1), Project Number QRX11028 References Bryden P, Mcknight D, Houston P. To Ask or Not to Ask: The Ethics of Informed Consent for Transesophageal Echocardiography Education[J]. Anesth Analg, 2018, 126(3): 752–753. Wang S, Wei J, Yuan S, et al. Intraoperative Transesophageal Echocardiography During Cardiovascular Surgery in China[J]. J Cardiothorac Vasc Anesth, 2019, 33(5): 1343–1350. Assaad S, Jr P A. A New Comer Steps to the Plate: Should Ultrasound Join the ICU Starting Lineup?[J]. 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Li F, Wei S, Le Y, et al. The significance of tissue doppler imaging in the diagnosis of left ventricular diastolic function[J]. Allied Academies, 2017(5). Title: Establishment of teaching and training model for transesophageal echocardiography based on swine Additional Declarations No competing interests reported. Supplementary Files rawdata.xlsx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3644628","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":256277723,"identity":"4763525c-3e6c-4697-81fb-199abddbafb9","order_by":0,"name":"Yamei ZHAO","email":"","orcid":"","institution":"Nanjing Frist Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yamei","middleName":"","lastName":"ZHAO","suffix":""},{"id":256277725,"identity":"04deb167-ceb4-4c98-8bc9-e9c250047e93","order_by":1,"name":"Xiao Zhou","email":"","orcid":"","institution":"Nanjing Frist Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Xiao","middleName":"","lastName":"Zhou","suffix":""},{"id":256277726,"identity":"ec5ab6b7-c8eb-4216-b1a5-38313275261f","order_by":2,"name":"Hanyu LIU","email":"","orcid":"","institution":"Nanjing Frist Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Hanyu","middleName":"","lastName":"LIU","suffix":""},{"id":256277727,"identity":"fc0e87df-3de8-433a-83a2-64f1b7b5c3ad","order_by":3,"name":"Zhenhong WANG","email":"","orcid":"","institution":"Nanjing Frist Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Zhenhong","middleName":"","lastName":"WANG","suffix":""},{"id":256277728,"identity":"2576d6fa-0006-4fa8-a365-e84188067295","order_by":4,"name":"Jialin YIN","email":"","orcid":"","institution":"Nanjing Frist Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jialin","middleName":"","lastName":"YIN","suffix":""},{"id":256277729,"identity":"4992dbea-1cdf-45ba-bab6-f6afb6e1c09b","order_by":5,"name":"Haiyan WEI","email":"","orcid":"","institution":"Nanjing Frist Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Haiyan","middleName":"","lastName":"WEI","suffix":""},{"id":256277730,"identity":"02c1889d-da4c-4614-8a6a-98994777fae2","order_by":6,"name":"Yali GE","email":"","orcid":"","institution":"Nanjing Frist Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yali","middleName":"","lastName":"GE","suffix":""},{"id":256277731,"identity":"9ebc3117-e0bd-48f0-9329-2b58c723d6e4","order_by":7,"name":"Hongwei SHI","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAnElEQVRIiWNgGAWjYFCCBDYGhgoJOXkStZyxMDZsIEkLY1tFIsMBYjXotqc/e8w7TyKBsYH54aMbxGgxO/PG3Jh3m0QeOwObsXEOUVpu5LBJ526TKGZs4GGTJlJL+jPp3DkSiQ0HiNeSYCad20CSljNvzKT/HJMwNmwm2i/H059Jzqipk5Nnb374mCgtCMBMmvJRMApGwSgYBfgAALowLacd8KHlAAAAAElFTkSuQmCC","orcid":"","institution":"Nanjing Frist Hospital","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Hongwei","middleName":"","lastName":"SHI","suffix":""},{"id":256277732,"identity":"f34f6d8d-a9ee-47cf-b97d-bb7edf66e7bb","order_by":8,"name":"Lihai CHEN","email":"","orcid":"","institution":"Nanjing Frist Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Lihai","middleName":"","lastName":"CHEN","suffix":""}],"badges":[],"createdAt":"2023-11-21 14:59:41","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3644628/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3644628/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":47741292,"identity":"1b1ae453-68f6-4d0d-b30e-ca8b628a9057","added_by":"auto","created_at":"2023-12-06 19:56:41","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":162724,"visible":true,"origin":"","legend":"\u003cp\u003eTEE model\u003c/p\u003e\n\u003cp\u003eNote: schematic diagram of TEE probe position in porcine esophagus.\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-3644628/v1/461b444c102b7eeb7f01b09b.jpeg"},{"id":47741293,"identity":"289422a0-f120-464b-825b-e08067c6f354","added_by":"auto","created_at":"2023-12-06 19:56:41","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":454166,"visible":true,"origin":"","legend":"\u003cp\u003eTEE images(1-6)\u003c/p\u003e\n\u003cp\u003eNote: (A) four-chamber view. (B) two-chamber view. (C) Long axis view. (D) Ascending aorta-LAX view. (E) Ascending aorta-SAX view. (F) AV LAX view.\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-3644628/v1/93897cd03f2c021602491063.jpeg"},{"id":47741296,"identity":"87ac0a52-b53f-4691-8c8d-7aba449a819e","added_by":"auto","created_at":"2023-12-06 19:56:41","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":465815,"visible":true,"origin":"","legend":"\u003cp\u003eTEE images(7-12)\u003c/p\u003e\n\u003cp\u003eNote: (A) AV SAX view. (B) RV inflow-outflow view. (C) Biatrial view. (D) Five-chamber view. (E) Mitral commissural view. (F) Right pulmonary vein view.\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-3644628/v1/2569aecbfff434c9ad85256d.jpeg"},{"id":47742928,"identity":"5cec124f-df4a-45ec-b969-e67b9b824083","added_by":"auto","created_at":"2023-12-06 20:04:41","extension":"jpeg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":655894,"visible":true,"origin":"","legend":"\u003cp\u003eTEE images(13-22)\u003c/p\u003e\n\u003cp\u003eNote: (A) Modified biatrial TV view. (B) Left pulmonary vein view. (C) Left atrial appendage view. (D) Aortic arch LAX view. (E) Aortic arch SAX view. (F) Descending aorta SAX view. (G) Descending aorta LAX view. (H) Modified LVOT view. (I) HPV view/ IVC view\u003c/p\u003e","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-3644628/v1/a9973b5fcd2130bb1ac2c242.jpeg"},{"id":55276977,"identity":"a55a0a51-1fe5-4ec6-9deb-56e467c36c17","added_by":"auto","created_at":"2024-04-25 05:17:19","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":827309,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3644628/v1/86a92979-8c1d-4c82-814d-99a6d42aec47.pdf"},{"id":47742927,"identity":"c5608462-9267-410c-b742-2173f97760d0","added_by":"auto","created_at":"2023-12-06 20:04:41","extension":"xlsx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":24942,"visible":true,"origin":"","legend":"","description":"","filename":"rawdata.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-3644628/v1/d07a7652a040d0746143d40a.xlsx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Establishment of teaching and training model for transesophageal echocardiography based on swine","fulltext":[{"header":"Short outline","content":"\u003cp\u003ePrevious research on the porcine model of TEE mainly focused on applications related to surgical treatment, while also lacking a comprehensive and detailed teaching and training of TEE porcine models. Our research endeavors to devise an advanced teaching and training protocol for TEE, while also establishing comprehensive baseline data for pig animal models. These baseline values will serve as a pivotal framework for the development of anatomically and pathophysiologically accurate pig heart models, utilizing the modality of echocardiography, in forthcoming investigations.The utilization of TEE animal models offers both simulated and real-time value, closely mirroring clinical scenarios. Clinicians can effectively acquire TEE simulation training through these animal models, thereby compensating for any limitations of electronic training models.\u003c/p\u003e"},{"header":"Introduction","content":"\u003cp\u003eTransesophageal echocardiography (TEE) is an effective monitoring tool for use during cardiac and noncardiac surgeries perioperatively. In an increasing number of clinical scenarios, TEE plays a significant role in various surgical procedures. However, TEE education programs in China primarily rely on simulation system and in-hospital patients. Some research has already focused on the ethics of practice in the operating room, which is one of the most important teaching and training, although there are some drawbacks and controversies. Nevertheless, due to economic constraints and ethical concerns\u003csup\u003e[1]\u003c/sup\u003e, an optimal live model for TEE teaching and training has yet to be established. It is crucial to cultivate more qualified clinical anesthesiologists, particularly cardiovascular anesthesiologists, and ultrasonologists to improve the standard of care\u003csup\u003e[2]\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eDue to the similarity in anatomy and structure between the hearts and vessels of domestic porcine and humans, domestic porcine have been extensively used as animal models in cardiovascular research, including studies on cardiovascular diseases and therapies like transcatheter therapies, cardiopulmonary resuscitation and acute myocardial infarction. Previous studies have investigated porcine models of TEE; however, they have primarily focused on the applications related to surgical treatment. Meanwhile, a comprehensive and detailed teaching and training porcine model for TEE is still lacking. Therefore, the objective of our study is to develop an enhanced teaching and training program for TEE and establish baseline values for the porcine animal model. These baseline values can serve as foundations for creating anatomical and pathophysiological porcine cardiac models using echocardiography in future studies.In addition, our simulation training using animal models aims to facilitate the rapid acquisition of manipulative techniques for obtaining echocardiographic views, thus enabling clinicians participating in the training program to enhance their proficiency.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eAnimals\u003c/h2\u003e \u003cp\u003eTen healthy domestic porcine aged 12\u0026ndash;18 months and weighing between 45-60kg were selected for this study. All the animal experiments were approved by the Animal Ethical Committee of Nanjing First Hospital, Nanjing Medical University, and all of the experiments were conducted in accordance with National Regulations on the Administration of Laboratory Animals.\u003c/p\u003e \u003cp\u003ePrior to the experiment, the animals should abstain from eating and drinking for at least 8 hours. All the porcine received a intramuscular injection of midazolam (0.5 mg/kg) and ketamine (10mg/kg) for anesthesia induction. Subsequently,, the porcine were positioned in the right lateral position on the operating table, with all four limbs secured. This positioning provides optimal access to the heart images in the porcine model. Following vein access which was established through the auricular vein using a 22G intravenous catheter, general anesthesia was inducted by administering a bolus injection of propofol (0.5-1mg/kg) and remifentanil (1\u0026ndash;2\u0026micro;g/kg) intravenously and the endotracheal intubation (size 6.0 F, for porcine of 45-60kg) was conducted when the postural and eyelash reflexes disappeared, and spontaneous breathing was retained during the induction. Mechanical ventilation mode was delivered in the form of intermittent positive pressure ventilation (IPPV) with the tidal volume being 6\u0026ndash;8 ml/kg, ventilation frequency 15 bpm, I/E 1:2. General anesthesia was maintained by intravenous and inhalation methods, and the combined anesthesia was administered with 2\u0026ndash;3% of sevoflurane in 100% oxygen concentration (oxygen flow 2L/min) and intravenous infusion of propofoll (2 mg/kg/h) and remifentanil(0.2 \u0026micro;g/kg/min) continuously. During the experiment, hydroxyethyl starch and saline were administered intravenously to meet physiological requirements. Continuous five-lead electrocardiogram (ECG) monitoring, SpO\u003csub\u003e2\u003c/sub\u003e through the skin sensor and invasive pressure measurements were conducted for basic hemodynamic monitoring.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eTransesophageal Echocardiography\u003c/h2\u003e \u003cp\u003eFollowing the induction of anesthesia, ensure the TEE probe was at neutral position and flexible, then the TEE probe was inserted into the oropharynx and advanced to the mid-esophagus using a laryngoscope for guidance(schematic diagram of TEE probe position in porcine esophagus, Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). To protect the TEE probe, a bite block and a roll of bandages were positioned in the mouth at an appropriate location. Establish a connection between the porcine and the 5-lead ECG on the echocardiography machine to obtain a continuous electrocardiographic signal. Mechanical ventilation was temporarily paused when ultrasound images were acquired. Starting from a mid-esophageal position, the thorough and comprehensive TEE examination was performed by an experienced cardiovascular anesthesiologist according to a clinical guideline\u003csup\u003e[3]\u003c/sup\u003e. One empirical anesthesiologist was responsible for anesthesia management and monitoring the vital signs, and another researcher was responsible for recording.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe examination was started at around 45\u0026ndash;48 cm from the maxillary incisors. In the mid-esophagus, the probe was gradually adjusted in a clockwise direction and anteflected. Adjusting the transducer angle to approximately 0\u0026ndash;10\u0026deg; enabled more specific imaging. The ME four-chamber view indicated the left atrium, right atrium, Left ventricle (LV), right ventricle (RV), mitral valve (MV), and Tricuspid valve (TV),.However, the quality of the right atrium and right ventricle imaging was slightly subpar, and the tricuspid valve did not appear clearly due to the difference of location of the main bronchus between porcine and humans. Based on ME 4C view, the flexion of the tip of the probe and the rotation of the transducer were adjusted continuously to obtain optimal two-dimensional ultrasound images of the heart chamber, walls and valves in the approaching middle-segment of the esophagus.\u003c/p\u003e \u003cp\u003eFrom the mid-esophagus position, the probe was rotated to the left with angles manipulated to 0\u0026ndash;10\u003cb\u003e\u0026deg;\u003c/b\u003e to obtain the short-axis (SAX) and long-axis (LAX) view of the descending aorta. Then, the probe was carefully withdrawn to obtain imaging of the aorta in the upper esophagus, including the aortic arch and the ascending aorta.. Upon visualizing the aortic arch, the modified views of the left and right ventricular outflow tracts became visible. These views can be utilized to measure cardiac output (inset). Subsequently, the probe was advanced slowly in search of transgastric views. However, in the porcine model, no additional transgastric views beyond the transgastric hepatic vein and inferior vena cava (IVC) view were obtainable. Furthermore, measurements of cardiac chamber and valve diameters were obtained. Assessment of left and right heart function was performed, along with measurement and analysis of valve function and blood flow.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eThe specific manipulating means were as follows:\u003c/h2\u003e \u003cp\u003e(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) ME 4-C view was obtained at the mid-esophageal level. Optimized images were obtained by manipulating the probe, involving anteflexion, right rotation, and left lateriflexion in the range of angles from 0\u0026ndash;15\u0026deg;.. Once the standard ME 4-C view was established, adjusting the angles of the plane allowed for visualization of different views. (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) With right rotation of the probe,, the ME 2-C view was obtained at angles ranging from 35\u0026ndash;60\u0026deg;.Additionally, at angles between 70\u0026ndash;100\u0026deg;, the long-axis view, which is also a three-chamber (3-C) view, could be visualized. (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e) In order to observe the structure and function of the mitral valve at the mid-esophageal level, the angle of the probe was adjusted to 35\u0026ndash;50\u0026deg; and the probe was flexed anteriorly to obtain a mitral commissural view. (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e) Moreover, a clear visualization of the left atrial appendage view was achieved by anteflexing the probe at angles ranging from 30\u0026ndash;60\u0026deg;. (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e) In the porcine model, obtaining the ME 5-C view proved to be more challenging when withdrawing the probe and applying anteflexion from the ME 4-C heart view (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e) The left and right pulmonary vein views were difficult to visualize even in humans. At the mid-esophageal level, the probe was adjusted for anteflexion and right rotation, and then, the left and right pulmonary vein views could be achieved at 30\u0026ndash;50\u0026deg; and 100\u0026ndash;120\u0026deg; respectively, and color Doppler was usually needed to assist in determining the acquisition of pulmonary veins.\u003c/p\u003e \u003cp\u003e(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e) At the mid-esophagus, other views could be acquired. From the long-axis view described in the preamble, advancing the probe could get the aortic valve LAX view when the aortic valve was put in the center of the frame with the angle range of 70\u0026ndash;100\u0026deg;, and the aortic valve SAX view could be obtained at the angle of 30\u0026ndash;50\u0026deg;. I Withdrawing the probe and adjusting the angle to 0\u0026ndash;50\u0026deg;, the ascending aorta SAX view can be acquired in the anteflexion position. The ascending aorta long-axis (LAX) view is obtained within the angle range of 70\u0026ndash;90\u0026deg;. (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e) By anteflexing and right-rotating the probe, the RV inflow-outflow view can be obtained from the aortic valve SAX view, within the angle range of 20\u0026ndash;60\u0026deg;. However, this view may result in shadowing of the pulmonary valve and tricuspid valve. Alternatively, the biatrial view can be acquired at an angle of 60\u0026ndash;100\u0026deg;..(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e) In instances where a more detailed assessment of the tricuspid valve was necessary, the probe can be flexed at an angle of 90\u0026ndash;120\u0026deg;. This maneuver, referred to as a modified biaxial TV view, enables visualization of both the left and right atria..\u003c/p\u003e \u003cp\u003e(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e) To visualize the great vessels, views at the level of the upper esophagus were indispensable. (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e) Generally, the descending aorta short-axis (SAX) view is acquired by withdrawing and rotating the probe to the left, maintaining an angle of 0\u0026deg; from the mid-esophageal four-chamber (ME 4-C) view. Subsequently, adjusting the angle to 80\u0026ndash;90\u0026deg; allows for visualization of the descending aorta long-axis (LAX) view. (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e) After acquiring the descending aortic SAX view, the probe is consistently withdrawn until the aortic arch is visualized. Subsequently, adjusting the angle to 60\u0026ndash;90\u0026deg; facilitates obtaining the aortic arch long-axis (LAX) view. (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e) Notably, at the aortic arch LAX view, a modified Left ventricular outflow tract (LVOT) view could be obtained. This enables the measurement of LVOT diameter and subsequent calculation of cardiac output (CO). In some cases of porcine, the pulmonary valve LAX and right cardiac outflow tract can be seen simultaneously. (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e) Due to the special anatomical structures of the porcine, all the transgastric short axis views of LV and RV were not obtained in the porcine model, only inferior vena cava(IVC) and hepatic vein(HPV) were found and shown when we probed the depth of the stomach at the angle of 60\u0026ndash;70\u0026deg; with the anteflexion and right rotation of the probe.\u003c/p\u003e \u003cp\u003eThe images of various views can be seen in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eTo evaluate TEE image quality\u003csup\u003e[4]\u003c/sup\u003e\u003c/h2\u003e \u003cp\u003eTEE conditions in the swine model were evaluated and graded as follows: Excellent: All structures are visualized with clear contours and can be easily identified.\u003c/p\u003e \u003cp\u003eGood: Structures are mostly of good contrast (distinct) and can be identified.\u003c/p\u003e \u003cp\u003ePoor: Visualization of structures is possible to only a limited degree. Evaluation of parameters is limited.\u003c/p\u003e \u003cp\u003eNot Possible: Visualization of structures is not possible even in different views, and evaluation or guidance cannot be conducted.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eThis study is an exploratory and observational research. All data were reorganized and inputted into an Excel spreadsheet (Version 2016, Microsoft), and statistical analysis was performed using the SPSS 20.0 (IBM). Descriptive statistics were conducted as appropriate according to the characteristics of the data. Continuous variables with normal distribution were expressed as the mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (\u003ci\u003ex̄±s\u003c/i\u003e), while categorical data were expressed as numbers and rates. A \u003cem\u003eP\u003c/em\u003e-value of \u0026lt;\u0026thinsp;0.05 was considered to indicate statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eProcedures of anesthesia and insertion of the probe in all ten porcine were practicable. We completed the exploration of all views, and most of the middle and upper esophageal views could be displayed, but none of the transgastric views of LV and RV could be obtained. Similarly, the measured parameters were obtained. Although all the porcine were healthy, one swine presented with an atrial septal defect and another was diagnosed with moderate aortic valve regurgitation.\u003c/p\u003e \u003cp\u003eWe conducted a comprehensive TEE examination, thoroughly examining all relevant details. According to recent research \u003csup\u003e[5]\u003c/sup\u003e, it is important to note that the anatomy of a porcine differs from that of a human. The main bronchus of porcine is situated between esophagus and heart. Specific recommendations for depth and transducer angles were presented in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e provides an overview of the anatomical and functional parameters of the porcine heart, encompassing measurements of left and right ventricular dimensions and function, aortic root and aortic dimensions, and functional parameters for all four valves.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe basic values of TEE images in porcine (n\u0026thinsp;=\u0026thinsp;10, x̄±s)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eView\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eSwine\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eHuman\u003csup\u003e[3]\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eManeuver\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAngle\u003c/p\u003e \u003cp\u003e(degree)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eDepth\u003c/p\u003e \u003cp\u003e(cm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eAngle\u003c/p\u003e \u003cp\u003e(degree)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003efour-chamber view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u0026ndash;15\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e44.7\u0026thinsp;\u0026plusmn;\u0026thinsp;4.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u0026ndash;10\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion, right rotation and left lateriflexion\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003etwo-chamber view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e35\u0026ndash;60\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e44.7\u0026thinsp;\u0026plusmn;\u0026thinsp;4.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e80\u0026ndash;100\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eRight rotation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLong axis view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e70\u0026ndash;100\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e45.5\u0026thinsp;\u0026plusmn;\u0026thinsp;3.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e120\u0026ndash;140\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eRight rotation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAscending aorta-LAX view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e50\u0026ndash;90\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e43.4\u0026thinsp;\u0026plusmn;\u0026thinsp;5.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e90\u0026ndash;110\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAscending aorta-SAX view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u0026ndash;50\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e44.7\u0026thinsp;\u0026plusmn;\u0026thinsp;5.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u0026ndash;30\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAV LAX view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e70\u0026ndash;100\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e46.3\u0026thinsp;\u0026plusmn;\u0026thinsp;4.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e120\u0026ndash;140\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion and right rotation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAV SAX view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e30\u0026ndash;50\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e46.5\u0026thinsp;\u0026plusmn;\u0026thinsp;3.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e25\u0026ndash;45\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion and right rotation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRV inflow-outflow view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20\u0026ndash;60\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e46.2\u0026thinsp;\u0026plusmn;\u0026thinsp;3.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e50\u0026ndash;70\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion and right rotation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eBiatrial view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e60\u0026ndash;100\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e46.4\u0026thinsp;\u0026plusmn;\u0026thinsp;3.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e90\u0026ndash;110\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion and right rotation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFive-chamber view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e44.5\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u0026ndash;10\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMitral commissural view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e35\u0026ndash;50\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e45.1\u0026thinsp;\u0026plusmn;\u0026thinsp;4.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e50\u0026ndash;70\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRight pulmonary vein view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e100\u0026ndash;120\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e46.2\u0026thinsp;\u0026plusmn;\u0026thinsp;4.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e90\u0026ndash;110\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eRight rotation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eModified biatrial TV view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e90\u0026ndash;120\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e46.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e50\u0026ndash;70\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion and right rotation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLeft pulmonary vein view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e30\u0026ndash;65\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e46.9\u0026thinsp;\u0026plusmn;\u0026thinsp;4.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u0026ndash;30\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLeft atrial appendage view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e30\u0026ndash;60\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e46.2\u0026thinsp;\u0026plusmn;\u0026thinsp;3.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e30\u0026ndash;60\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion and left rotation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAortic arch LAX view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e38.9\u0026thinsp;\u0026plusmn;\u0026thinsp;3.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u0026ndash;10\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNeutral position\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAortic arch SAX view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e60\u0026ndash;90\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e38.9\u0026thinsp;\u0026plusmn;\u0026thinsp;3.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e70\u0026ndash;90\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNeutral position\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDescending aorta SAX view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e45.5\u0026thinsp;\u0026plusmn;\u0026thinsp;3.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u0026ndash;10\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNeutral position\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eME\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDescending aorta LAX view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e80\u0026ndash;90\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e45.2\u0026thinsp;\u0026plusmn;\u0026thinsp;4.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e90\u0026ndash;100\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNeutral position\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eModified LVOT view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e38.9\u0026thinsp;\u0026plusmn;\u0026thinsp;3.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e100\u0026ndash;130\u0026deg;(ME)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNeutral position\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTG\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHPV view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e60\u0026ndash;75\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e56.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e/\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTG\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eIVC view\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e50\u0026ndash;75\u0026deg;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e56.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e/\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnteflexion\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe values of anatomic and functional parameters of heart in porcine(n\u0026thinsp;=\u0026thinsp;10, x̄±s\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eParameters\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eValues\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"6\" rowspan=\"7\"\u003e \u003cp\u003eLV function\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLVESd (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e21.87\u0026thinsp;\u0026plusmn;\u0026thinsp;4.46\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLVEDd(mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e36.67\u0026thinsp;\u0026plusmn;\u0026thinsp;4.50\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLVESV(ml)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e14.20\u0026thinsp;\u0026plusmn;\u0026thinsp;5.84\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLVEDV(ml)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e46.84\u0026thinsp;\u0026plusmn;\u0026thinsp;16.59\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLVEF(%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e69.33\u0026thinsp;\u0026plusmn;\u0026thinsp;6.94\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSV(ml)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e56.34\u0026thinsp;\u0026plusmn;\u0026thinsp;14.26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCO(ml/min)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e4.05\u0026thinsp;\u0026plusmn;\u0026thinsp;0.95\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"7\" rowspan=\"8\"\u003e \u003cp\u003eAorta valve and aorta\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAortic annulus diameter(mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e19.09\u0026thinsp;\u0026plusmn;\u0026thinsp;2.15\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSinus of Valsalva diameter (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e24.33\u0026thinsp;\u0026plusmn;\u0026thinsp;6.14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSinotubular junction diameter (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e21.91\u0026thinsp;\u0026plusmn;\u0026thinsp;7.39\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAscending aorta diameter(mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e20.49\u0026thinsp;\u0026plusmn;\u0026thinsp;2.84\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDescending aorta diameter (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e14.27\u0026thinsp;\u0026plusmn;\u0026thinsp;5.05\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMax. jet velocity aortic valve (cm/s)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e125.22\u0026thinsp;\u0026plusmn;\u0026thinsp;16.51\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMax.PG\u003csub\u003eAV\u003c/sub\u003e (mmHg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e6.37\u0026thinsp;\u0026plusmn;\u0026thinsp;1.67\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMean PG\u003csub\u003eAV\u003c/sub\u003e (mmHg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.82\u0026thinsp;\u0026plusmn;\u0026thinsp;0.47\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"5\" rowspan=\"6\"\u003e \u003cp\u003eMitral valve\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMitral valve diameter ap(mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e16.76\u0026thinsp;\u0026plusmn;\u0026thinsp;14.74\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMitral valve diameter cc(mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e9.85\u0026thinsp;\u0026plusmn;\u0026thinsp;9.12\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEffective area of mitral orifice (cm\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e3.66\u0026thinsp;\u0026plusmn;\u0026thinsp;0.63\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTransmitral peak early(E wave) velocity (cm/s)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e79.59\u0026thinsp;\u0026plusmn;\u0026thinsp;14.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMax.gradient of E wave velocity (mmHg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e2.60\u0026thinsp;\u0026plusmn;\u0026thinsp;1.02\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMean gradient of E wave velocity (mmHg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.32\u0026thinsp;\u0026plusmn;\u0026thinsp;0.52\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eRV function\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFAC (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e49.25\u0026thinsp;\u0026plusmn;\u0026thinsp;7.16\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTAPSE (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.74\u0026thinsp;\u0026plusmn;\u0026thinsp;0.21\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eTricuspid valve\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTranstricuspid peak early(E wave) velocity (cm/s)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e56.2\u0026thinsp;\u0026plusmn;\u0026thinsp;9.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMax.gradient of E wave velocity (mmHg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.30\u0026thinsp;\u0026plusmn;\u0026thinsp;0.42\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMean gradient of E wave velocity (mmHg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.33\u0026thinsp;\u0026plusmn;\u0026thinsp;1.68\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003ePulmonary valve\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMax jet velocity of pulmonary valve (cm/s)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e82.96\u0026thinsp;\u0026plusmn;\u0026thinsp;26.68\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMax gradient of pulmonary valve (mmHg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e3.04\u0026thinsp;\u0026plusmn;\u0026thinsp;2.11\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMean gradient of pulmonary valve (mmHg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e1.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.82\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003eNote: TAPSE (tricuspid annular plane systolic excursion); FAC (fractional area change); Max.PG AV (maximum pressure gradient of blood flow through aortic valve); Mean PG AV (mean pressure gradient of blood flow through aortic valve).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eSwine have increasingly been utilized in various cardiovascular pathophysiological models, including pulmonary artery regurgitation\u003csup\u003e[6]\u003c/sup\u003e, hemorrhagic shock model\u003csup\u003e[7]\u003c/sup\u003e, transcatheter therapies model\u003csup\u003e[8\u0026ndash;10]\u003c/sup\u003e, cardiopulmonary resuscitation model\u003csup\u003e[11]\u003c/sup\u003e, etc.. Researchers have employed TEE as a valuable tool to effectively assess cardiovascular structures and function in porcine. Previous studies have investigated the porcine model of TEE\u003csup\u003e[4,5]\u003c/sup\u003e, but none have provided such detailed exploration as this study. Additionally, data on porcine models of TEE remain limited. Consequently, we proceeded to investigate the baseline values of cardiac ultrasound images based on TEE in swine from anatomical structure, valve function and hemodynamic monitoring. Theses findings not only support the development of a simulated physiological cardiac TEE teaching model, but also provide a foundation for future studies involving pathological and therapeutic models.\u003c/p\u003e \u003cp\u003ePresently, TEE training in China predominantly relies on e-learning through echocardiography simulation systems and clinical training in the operating room. However, intraoperative TEE has evolved to non-cardiac surgery and out-operating room monitoring, which diminishes the training opportunities of TEE in many medical centers. While the CAE Vimedix Simulator, a perioperative transesophageal echocardiography simulator,provides valuable training for basic image interpretation\u003csup\u003e[12]\u003c/sup\u003e, cost constraints prevent certain medical institutions in China from acquiring such resources. Furthermore, the aforementioned training primarily focuses on basic images depicting anatomical and physiological conditions, rather than encompassing pathological models. Nevertheless, utilizing an animal ultrasound model offers a more realistic representation of the clinical setting.\u003c/p\u003e \u003cp\u003eTo achieve optimal image quality, we experimented with various positions during the examination and eventually set the position of porcine in the right lateral-recumbency as it proved to be more advantageous than supine or the left lateral-recumbency. It is of a great possibility that the heart is closer to the esophagus due to the gravity in the right lateral-recumbency, which facilitated the acquisition of ultrasound images and improved the image quality. In a similar study, healthy dogs had minor stroke volume and LVET (left ventricular ejection time) in the supine position compared to that in left and right lateral-recumbency, but other parameters showed no significant difference. While our study primarily focused on establishing clear and practical images and baseline values, we did not extensively investigate the impact of various positions. In addition, transthoracic echocardiography(TTE) was also conducted in the meantime, and the short-axis image of LV and RV based TTE can compensate for the absence of transgastric TEE images, but it was not the main purpose of the current research, which will not be elaborated here.\u003c/p\u003e \u003cp\u003eSwine, belonging to the artiodactyla family, exhibit cardiac and vascular structures that are similar to those of humans. Due to the special location of the main bronchus and stomach, it was impossible to detect some cavities that are easy to find in human, like transgastric section. Furthermore, the deep transgastric view holds significant importance in measuring cardiac output within the left ventricular outflow tract. Although due to anatomical limitations, we were unable to obtain a good gastric basal short-axis view, which would provide us with the same kind of CO measurements as in the human body, we were able to identify a modified view in the upper esophageal region that can serve as an alternative for calculating CO.\u003c/p\u003e \u003cp\u003ePorcine weighing between 45-60kg, which were included in this study, possess heart structures that exhibit a high degree of similarity to human hearts.. These studied porcine demonstrated notable similarities in terms of cardiac chambers, walls, valve function, heart function, and even cardiac output. Interestingly, the measured cardiac output in porcine was reported to be higher than that in humans, as assessed through tissue Doppler imaging\u003csup\u003e[13]\u003c/sup\u003e. However, in the RT-3D TEE imaging examination, we found that the angles and orientations of the mitral and aortic valves were different from those of humans anatomically, that between the mitral valve plane and the aortic annulus was found to be about 80\u0026deg; (median number) in porcine. It should be noted that sternotomy was not performed in our study to validate the data concerning the heart chambers and walls acquired through TEE.\u003c/p\u003e \u003cp\u003eIn conclusion, performing transesophageal echocardiography in pigs yields replicable and comparable results to that in humans, highlighting the feasibility of implementing a teaching model. Utilizing the animal model allows clinicians to receive effective simulation training in TEE, thereby addressing the limitations of electronic training models. The key advantage lies in the simulation and real-time applicability of TEE animal models, which closely resemble clinical scenarios. In this study, TEE baseline values were acquired, providing a foundation for further development of the experimental porcine model. However, this study has certain limitations. In this study, we only focused on acquiring basic anatomical and physiological values of the transesophageal echocardiography (TEE) model and did not establish certain pathological models, which will be the main direction of further research.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eConclusively, the conduction of transesophageal echocardiography in porcine is replicable and similar to humans\u0026rsquo;, for that it\u0026rsquo;s feasible to initiate a teaching model. Clinicians could get effective TEE simulation training through the animal model to make up for the deficiency of the electronic training model. The key is the simulation and real-time value of TEE animal models, which are more closely related to clinical situations.TEE baseline values were acquired for more development in the experimental porcine model.\u003c/p\u003e "},{"header":"Declarations","content":"\u003cp\u003eThe authors confirm that the study is reported in accordance with ARRIVE guidelines.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study available from the corresponding author on reasonable request. All data generated or analysed during this study are included in this published article [and its supplementary information \u0026nbsp;files].\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNanjing GaoFeng Talent Project (YY-104 to LC).\u003c/p\u003e\n\u003cp\u003eNanjing Health Youth Talent Training Project (Level 1), Project Number QRX11028\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eBryden P, Mcknight D, Houston P. To Ask or Not to Ask: The Ethics of Informed Consent for Transesophageal Echocardiography Education[J]. Anesth Analg, 2018, 126(3): 752\u0026ndash;753.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang S, Wei J, Yuan S, et al. Intraoperative Transesophageal Echocardiography During Cardiovascular Surgery in China[J]. J Cardiothorac Vasc Anesth, 2019, 33(5): 1343\u0026ndash;1350.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAssaad S, Jr P A. A New Comer Steps to the Plate: Should Ultrasound Join the ICU Starting Lineup?[J]. J Cardiothorac Vasc Anesth, 2018, 32(1):361\u0026ndash;362.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHuenges K, Pokorny S, Berndt R, et al. Transesophageal Echocardiography in Swine: Establishment of a Baseline[J]. Ultrasound Med Biol, 2017, 43(5): 974\u0026ndash;980.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eS\u0026uuml;ndermann S H, Cesarovic N, Falk V, et al. Two- and three-dimensional transoesophageal echocardiography in large swine used as model for transcatheter heart valve therapies: standard planes and values[J]. Interactive CardioVascular and Thoracic Surgery, 2016, 22(5): 580\u0026ndash;586.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKopic S, Stephensen S S, Heiberg E, et al. Isolated pulmonary regurgitation causes decreased right ventricular longitudinal function and compensatory increased septal pumping in a porcine model[J]. Acta Physiol (Oxf), 2017, 221(3): 163\u0026ndash;173.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTeeter W A, Conti B M, Wasicek P J, et al. Feasibility of basic transesophageal echocardiography in hemorrhagic shock: potential applications during resuscitative endovascular balloon occlusion of the aorta (REBOA)[J]. Cardiovasc Ultrasound, 2018, 16(1): 12.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCaneiro-Queija B, R Est\u0026eacute;vez-Loureiro, Calvo-Iglesias F, et al. Combined transcatheter mitral and tricuspid repair with MitraClip: first experience in Spain[J]. Revista Espa\u0026ntilde;ola de Cardiolog\u0026iacute;a (English Edition), 2020, 73( 12):1073\u0026ndash;1074.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWebb J G, Murdoch D J, Boone R H, et al. Percutaneous Transcatheter Mitral Valve Replacement[J]. Journal of the American College of Cardiology, 2019, 73(11):1239\u0026ndash;1246.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMosala Nezhad Z, Poncelet A, Fervaille C, et al. Experimental Aortic Valve Cusp Extension with CorMatrix in a Porcine Model[J]. Thorac Cardiovasc Surg, 2017, 65(3): 206\u0026ndash;210.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAnderson K L, Castaneda M G, Boudreau S M, et al. Left Ventricular Compressions Improve Hemodynamics in a Swine Model of Out-of-Hospital Cardiac Arrest[J]. Prehosp Emerg Care, 2017, 21(2): 272\u0026ndash;280.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWeber U, Zapletal B, Base E, et al. Resident performance in basic perioperative transesophageal echocardiography: Comparing 3 teaching methods in a randomized controlled trial[J]. Medicine (Baltimore), 2019, 98(36): e17072.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLi F, Wei S, Le Y, et al. The significance of tissue doppler imaging in the diagnosis of left ventricular diastolic function[J]. Allied Academies, 2017(5).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTitle: Establishment of teaching and training model for transesophageal echocardiography based on swine\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"transesophageal echocardiography, animal model, education","lastPublishedDoi":"10.21203/rs.3.rs-3644628/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3644628/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe education programs for transesophageal echocardiography (TEE), which plays significant roles in various surgical procedures, in China is currently limited to stimulation system and in-hospital patients. Although, existing TEE simulators have become increasingly sophisticated, the use of animal models retains significant advantages in terms of enabling dynamic cardiac monitoring. The aim of this study is to develop a better teaching and training program for TEE and establish baseline values for the porcine animal model. The thorough TEE examinations were conducted in 10 domestic porcine weighing 45-60kg according to ASA guideline for TEE. All the recommended views were explored and saved. The depth and angles of each view were recorded. Additionally, hemodynamic measurements were performed and recorded. All parameters were compared with human reference values. The porcine model is feasible to initiate a teaching model, and TEE baseline values were acquired for more development in the experimental porcine model.\u003c/p\u003e","manuscriptTitle":"Establishment of teaching and training model for transesophageal echocardiography based on swine","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-12-06 19:56:36","doi":"10.21203/rs.3.rs-3644628/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"335a93ce-e456-41aa-bbe9-2c5acf923f5d","owner":[],"postedDate":"December 6th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":27068493,"name":"Health sciences/Anatomy"},{"id":27068494,"name":"Health sciences/Diseases"}],"tags":[],"updatedAt":"2024-04-25T05:11:47+00:00","versionOfRecord":[],"versionCreatedAt":"2023-12-06 19:56:36","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3644628","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3644628","identity":"rs-3644628","version":["v1"]},"buildId":"7rjqhiLT3MXkJMwkYKINL","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}