Project no. NVKP_16-1&#8211;2016-0017 (&#8217;National Heart Program&#8217;) has been implemented with the support provided from the National Research, Development and Innovation Fund of Hungary, financed under the NVKP_16 funding scheme. The research was financed by the Thematic Excellence Programme (2020-4.1.1.-TKP2020) of the Ministry for Innovation and Technology in Hungary, within the framework of the Therapeutic Development and Bioimaging thematic programmes of the Semmelweis University.

The protocol follows the guidelines of the institution&#39;s human research ethics committee and the patients of the clinical cases gave their written informed consent to the study.
1. Technical requirements
<ol>
	<li>For 3D acquisition and analysis, use appropriate software and hardware. Use ECG cables of the echocardiography device; moreover, it is mandatory for the complete 3D acquisition protocol described below.</li>
	<li>For 3D acquisition, use a 3D echocardiographic probe and 3D-compatible ultrasound machine. For 3D RV volumetric analysis, use dedicated software.</li>
</ol>
2. Acquisition
<ol>
	<li>In the vast majority of cases, perform 3D acquisition of the RV using apical views. In opposed to the LV-focused views, a different patient positioning is recommended. If substantially better image quality can be achieved by switching to one intercostal space over the correct apical view, this foreshortened view may enable better 3D image quality. The foreshortening can be corrected during 3D analysis.
	<ol>
		<li>Compared to the standard apical echocardiographic acquisition, where the left lateral decubitus position (patient lying on the left side with the left arm stretched above the head) is recommended, have the patient lean back slightly more to enable a more lateral position of the transducer.</li>
		<li>Choose an image depth that only includes the RV. Unnecessarily large depth may lower the acquisition frame rate with the lack of beneficial effects regarding RV volumetric analysis.</li>
	</ol>
	</li>
	<li>Confirm the correct RV-focused view from 2D echocardiography images. If the free wall of the RV is poorly visualized even from this view, the expected 3D image quality will not be optimal for further analysis.</li>
	<li>Switch to the live 3D imaging using the 4D button, where further correction of the RV view can be performed.</li>
	<li>While the 3D live mode may be quite pleasing aesthetically, use the 12 Slice mode for the 3D view, which shows a triplane image of the region of interest as well as 9 cross-sectional planes that can be freely modified. By rotation and correct positioning of the cut planes, confirm the visibility of the entire RV free wall (including the outflow tract and apical segments).</li>
	<li>Further adjust the image by using the left tilting of the sector (second page on the touch screen) to improve RV visualization.</li>
	<li>Use two 3D acquisition modes for RV volumetric analysis: the multi beat and the single beat mode. Use both of these approaches in every patient however, in some cases (e.g., certain arrhythmias, severe dyspnea of the patient), only the latter one may be feasible.</li>
	<li>Using single beat mode, achieve a tradeoff between image quality and frame rate. Choose an optimal image depth, width, and frame rate (lower panel of the touch screen) and obtain 3D loops of the RV without any further action. This method is feasible in the majority of patients; however, it yields generally lower image quality and frame rate compared to the multi beat approach.
	<ol>
		<li>In case of an average (60-70/min) heart rate, keep a lower frame rate limit of 16 frames/s for adequate RV analysis; however, if tachycardia is present even higher frame rates are recommended.</li>
	</ol>
	</li>
	<li>Using the multi beat mode, reconstruct the acquired 3D loop from a given number of heart cycles that can be selected on the touch screen (2,3,4 and 6 beat modes can be used). In contrast with the single beat acquisition, generally better image quality and frame rate are expected; however, it requires relatively constant heart cycle lengths and also patient compliance due to the mandatory breath-hold maneuver. The maneuver is essential to avoid the so-called stitching artefacts: when the acquired 3D volume is stitched together, unequal cardiac cycle lengths and/or motion due to breathing may result in this phenomenon.
	<ol>
		<li>After correct positioning of the probe and setting of the machine (similarly to &#34;single beat&#34; mode), ask the patient to take a deep breath and hold it. In this case, the expanding lungs usually cover the entire image.</li>
		<li>Ask the patient to exhale slowly, strictly with guidance. In parallel with the deflation of the lungs, the RV becomes visible again.</li>
		<li>When the entire RV (free wall and septum) reappears, ask the patient to hold breath in this state.</li>
		<li>By clicking to multi beat on the screen, begin the acquisition, and the 3D loop builds up during the given amount of heart cycles.</li>
		<li>When the acquisition is ready (the entire RV is visualized), ask the patient to breathe freely again.</li>
		<li>Check the obtained loop to ensure if there are no stitching or drop-out artifacts.</li>
	</ol>
	</li>
</ol>
3. 4D RV analysis
<ol>
	<li>Using dedicated software, perform 3D volumetric analysis of the RV. After choosing the RV-focused 3D loop from the patient library, open the software from the Measurement window found in the Volume folder.</li>
	<li>After opening the software, orient the RV on four predefined cut planes.
	<ol>
		<li>Put two markers (TV Center) to the center of the tricuspid valve in the upper and lower left long-axis planes. Adjust the long-axis of the image to the actual long axis of the RV by using the rotation tool. Reference images on the upper right edges show how the correct orientation should appear.</li>
		<li>On the upper and lower right panels, align the short-axis images into the correct position by rotation. Similarly to the previous step, reference images help in this process as well.</li>
	</ol>
	</li>
	<li>After finishing, click Set landmarks to the next step of the analysis. Set landmarks in two images.
	<ol>
		<li>On the left side, mark the tricuspid annulus at the free wall (TV free wall) and septum (TV septum) and the RV apex on the previously oriented apical four-chamber view.</li>
		<li>On the right side, set the RV posterior (LV/RV posterior) and anterior insertion points (LV/RV anterior) and the RV free wall (RV free wall). Similarly to the previous window, reference images in the upper right corner help regarding the correct setup. After setting all landmarks, the software automatically jumps to the next window (Review).</li>
	</ol>
	</li>
	<li>In this window (Review), review and manually correct the automatic endocardial border detection throughout the entire cardiac cycle, if necessary. By default, 9 panels can be seen: on the left side, 3 moving loops (1 long-axis and 2 short-axis), on the middle the end-diastolic frames of the same images, and on the right side the end-systolic ones.
	<ol>
		<li>In the case of false tracking, freely correct the endocardial borders (green lines), the tracked border by clicking on them. Using the rotation tool on the short axis, review images tracking along the entire circumference of the RV. Adjust the magnitude of correction by choosing Pen size on the right side panel. If the tracking is considered to be correct, click on the Results in the same panel.</li>
	</ol>
	</li>
	<li>In the last section, review the final 3D volumetric data and other calculated parameters on the upper right side (Worksheet panel). Beyond RV volumes and ejection fraction, the software also displays 2D parameters, such as linear (mid, basal, and long-axis) diameters, as well as FAC and TAPSE values derived from the predefined apical four-chamber view. The software also shows a long- and short axis of the RV (left side), a 3D live model of the RV (upper middle), and a volume-time curve of the chamber (lower right).
	<ol>
		<li>In case of the need for further adjustments in the tracking, every previous steps are available for correction by clicking on them on the right panel. If the tracking and the 3D parameters are considered to be valid, save the results by clicking on &#34;Approve and exit&#34; on the same panel.</li>
	</ol>
	</li>
</ol>

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3D analysis of the RV represents an important step in everyday cardiology practice. In parallel with the growing interest of the morphology and function of the previously neglected cardiac chamber, these novel solutions provide clinically meaningful information about the right side of the heart. While 3D acquisition has several aspects that markedly differ from 2D echocardiographic imaging, by keeping special attention to the critical points and by using a thorough protocol, 3D RV analysis may progress from a scientific ...

Echocardiography came a long way from its first clinical applications in the 1950s1. The first one-dimensional ultrasound probes were designed to provide simple linear diameters of the chamber walls and lumens; however, they undoubtedly represent a milestone in cardiovascular imaging. The development of two-dimensional (2D) ultrasound imaging was another major step by providing much more precise quantification of morphology and function and is still considered to be the standard method in everyday clinical practice. Nevertheless, 2D echocardiography-based assessment still carries a major limitation of the technique: imaging of a given chamber from a few tomographic planes does not adequately characterize the morphology and function of a three-dimensional (3D) structure. This problem is even more pronounced in the case of the right ventricle (RV): compared to the relatively simple bullet-shaped left ventricle (LV), the RV has a complex geometry2 that cannot be adequately quantified using linear diameters or areas3. Despite these widely known facts, RV morphology and function are usually measured by such simple parameters in the clinical practice.
For many decades, the RV was considered to have a much less important role in circulation compared to its left counterpart. Several landmark papers defeated this standpoint showing the strong prognostic role of RV geometry and function in a wide variety of diseases4,5,6,7. Numerous studies demonstrated the incremental value of RV measurement even by using relatively simple conventional parameters, which highlights the importance and need for more precise quantification of the chamber with potentially meaningful clinical value.
3D echocardiography overcomes several limitations of the 2D assessment of the cardiac chambers. While the measurement of volumes and also functional parameters free of geometrical assumptions may be of high interest in the case of the LV as well, it may gain particular importance in the assessment of the RV8. 3D-derived RV volumes and ejection fraction (EF) are shown to have significant prognostic value in various cardiovascular conditions9,10.
Nowadays, several vendors provide semi-automated solutions for 3D RV assessment with validated results against gold standard cardiac magnetic resonance (MR) measurements11,12. The technical requirements of 3D assessment are essential parts of a state-of-the-art cardiovascular imaging department nowadays, and it is expected that it will soon be part of the general equipment in every echocardiography lab. With proper expertise in 3D acquisition and post-processing, 3D RV analysis can be easily implemented into the standard examination protocol.

<table><tbody><tr><td>3V-D/4V-D/4Vc-D</td><td>General Electric</td><td>n.a.</td><td>ultrasound probe</td></tr><tr><td>4D Auto RVQ</td><td>General Electric</td><td>n.a.</td><td>software for analysis</td></tr><tr><td>E9/E95</td><td>General Electric</td><td>n.a.</td><td>ultrasound machine</td></tr><tr><td>EchoPac v203</td><td>General Electric</td><td>n.a.</td><td>software for analysis</td></tr></tbody></table>

morphological and functional assessment of the right ventricle using 3d echocardiography

Traditionally, it was believed that the right side of the heart has a minor role in circulation; however, more and more data suggest that right ventricular (RV) function has strong diagnostic and prognostic power in various cardiovascular disorders. Due to its complex morphology and function, assessment of the RV by conventional two-dimensional echocardiography is limited: the everyday clinical practice usually relies on simple linear dimensions and functional measures. Three-dimensional (3D) echocardiography overcame these limitations by providing volumetric quantification of the RV free of geometrical assumptions. Here, we offer a step-by-step guide to obtain and analyze 3D echocardiographic data of the RV using the leading commercially available software. We will quantify 3D RV volumes and ejection fraction. Several technical aspects may help to improve the quality of RV acquisition and analysis as well, which we present in a practical manner. We review the current opportunities and the limiting factors of this method and also highlight the potential applications of 3D RV assessment in current clinical practice.

3D analysis of the RV is feasible in a wide variety of cardiovascular diseases. Case 1 is a healthy volunteer with normal ventricular volumes and function (Figure 1). Case 2 is a post-mitral valve repair patient who is a typical example for the conflicting results of conventional 2D assessment: while TAPSE is markedly reduced, the patient does not show any signs of RV dysfunction and a maintained RV global systolic function was confirmed by normal 3D RV EF (<...

Watch this Scientific Journal Video about Morphological and Functional Assessment of the Right Ventricle Using 3D Echocardiography at JoVE.com

Morphological and Functional Assessment of the Right Ventricle Using 3D Echocardiography

Here, we provide a step-by-step acquisition and analysis protocol for the 3D volumetric assessment of the right ventricle, mainly focusing on the practical aspects that maximize the feasibility of this technique.

Traditionally, it was believed that the right side of the heart has a minor role in circulation; however, more and more data suggest that right ...

morphological-functional-assessment-right-ventricle-using-3d

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2.8K Views.  Semmelweis University Heart and Vascular Center. Here, we provide a step-by-step acquisition and analysis protocol for the 3D volumetric assessment of the right ventricle, mainly focusing on the practical aspects that maximize the feasibility of this technique.

Video: Morphological and Functional Assessment of the Right Ventricle Using 3D Echocardiography

Echocardiographic Assessment of the Right Heart in Mice

Transgenic and toxic models of pulmonary arterial hypertension (PAH) are widely used to study the pathophysiology of PAH and to investigate potential therapies. Given the expense and time involved in creating animal models of disease, it is critical that researchers have tools to accurately assess phenotypic expression of disease. Right ventricular dysfunction is the major manifestation of pulmonary hypertension. Echocardiography is the mainstay of the noninvasive assessment of right ventricular function in rodent models and has the advantage of clear translation to humans in whom the same tool is used. Published echocardiography protocols in murine models of PAH are lacking.
In this article, we describe a protocol for assessing RV and pulmonary vascular function in a mouse model of PAH with a dominant negative BMPRII mutation; however, this protocol is applicable to any diseases affecting the pulmonary vasculature or right heart. We provide a detailed description of animal preparation, image acquisition and hemodynamic calculation of stroke volume, cardiac output and an estimate of pulmonary artery pressure.

This article provides a protocol for the echocardiographic assessment of right ventricular size and pulmonary hypertension in mice. Applications include phenotype determination and serial assessment in transgenic and toxin-induced mouse models of cardiomyopathy and pulmonary vascular disease.

Transgenic and toxic models of pulmonary arterial hypertension (PAH) are widely used to study the pathophysiology of PAH and to investigate potential ...

Assessment of Right Ventricular Structure and Function in Mouse Model of Pulmonary Artery Constriction by Transthoracic Echocardiography

Emerging clinical data support the notion that RV dysfunction is critical to the pathogenesis of cardiovascular disease and heart failure1-3. Moreover, the RV is significantly affected in pulmonary diseases such as pulmonary artery hypertension (PAH). In addition, the RV is remarkably sensitive to cardiac pathologies, including left ventricular (LV) dysfunction, valvular disease or RV infarction4. To understand the role of RV in the pathogenesis of cardiac diseases, a reliable and noninvasive method to access the RV structurally and functionally is essential.
A noninvasive trans-thoracic echocardiography (TTE) based methodology was established and validated for monitoring dynamic changes in RV structure and function in adult mice. To impose RV stress, we employed a surgical model of pulmonary artery constriction (PAC) and measured the RV response over a 7-day period using a high-frequency ultrasound microimaging system. Sham operated mice were used as controls. Images were acquired in lightly anesthetized mice at baseline (before surgery), day 0 (immediately post-surgery), day 3, and day 7 (post-surgery). Data was analyzed offline using software.
Several acoustic windows (B, M, and Color Doppler modes), which can be consistently obtained in mice, allowed for reliable and reproducible measurement of RV structure (including RV wall thickness, end-diastolic&#160;and end-systolic dimensions), and function (fractional area change, fractional shortening, PA peak velocity, and peak pressure gradient) in normal mice and following PAC.
Using this method, the pressure-gradient resulting from PAC was accurately measured in real-time using Color Doppler mode and was comparable to direct pressure measurements performed with a Millar high-fidelity microtip catheter. Taken together, these data demonstrate that RV measurements obtained from various complimentary views using echocardiography are reliable, reproducible and can provide insights regarding RV structure and function. This method will enable a better understanding of the role of RV cardiac dysfunction.

Right ventricle (RV) dysfunction is critical to the pathogenesis of cardiovascular disease, yet limited methodologies are available for its evaluation. Recent advances in ultrasound imaging provide a noninvasive and accurate option for longitudinal RV study. Herein, we detail a step-by-step echocardiographic method using a murine model of RV pressure overload.

Emerging clinical data support the notion that RV dysfunction is critical to the pathogenesis of cardiovascular disease and heart failure1-3. Moreover, ...

Echocardiographic Approaches and Protocols for Comprehensive Phenotypic Characterization of Valvular Heart Disease in Mice

The aim of this manuscript and accompanying video is to provide an overview of the methods and approaches used for imaging heart valve function in rodents, with detailed descriptions of the appropriate methods for anesthesia, the echocardiographic windows used, the imaging planes and probe orientations for image acquisition, the methods for data analysis, and the limitations of emerging technologies for the evaluation of cardiac and valvular function. Importantly, we also highlight several future areas of research in cardiac and heart valve imaging that may be leveraged to gain insights into the pathogenesis of valve disease in preclinical animal models. We propose that using a systematic approach to evaluating cardiac and heart valve function in mice can result in more robust and reproducible data, as well as facilitate the discovery of previously underappreciated phenotypes in genetically-altered and/or physiologically-stressed mice.

This protocol provides a detailed description of the echocardiographic approach for comprehensive phenotyping of heart and heart valve function in mice.

The aim of this manuscript and accompanying video is to provide an overview of the methods and approaches used for imaging heart valve function in ...

Evaluation of Left Ventricular Structure and Function using 3D Echocardiography

Three-dimensional (3D) quantification of the left ventricle (LV) provides significant added value in terms of diagnostic accuracy and precise risk stratification in various cardiac disorders. Recently, 3D echocardiography became available in routine cardiology practice; however, high-quality image acquisition and subsequent analysis have a steep learning curve. The present article aims to guide the reader through a detailed 3D protocol by presenting tips and tricks and also by highlighting the potential pitfalls to facilitate the widespread but technically sound use of this important technique concerning the LV. First and foremost, we show the acquisition of a high-quality 3D dataset with optimal spatial and temporal resolution. Then, we present the analytical steps toward a detailed quantification of the LV by using one of the most widely applied built-in software. We will quantify LV volumes, sphericity, mass and also systolic function by measuring ejection fraction and myocardial deformation (longitudinal and circumferential strain). We will discuss and provide clinical examples about the essential scenarios where the transition from a conventional echocardiographic approach to a 3D-based quantification is highly recommended.

In this article, we provide a step-by-step acquisition and analysis protocol for the volumetric assessment and speckle-tracking analysis of the left ventricle by 3D echocardiography, particularly focusing on practical aspects that maximize the feasibility of this technique.

Three-dimensional (3D) quantification of the left ventricle (LV) provides significant added value in terms of diagnostic accuracy and precise risk ...

Bioengineering

Three-Dimensional Echocardiographic Method for the Visualization and Assessment of Specific Parameters of the Pulmonary Veins

The dimensions of the pulmonary veins are important parameters when planning pulmonary vein isolation (PVI), especially with the cryoballoon ablation technique. Acknowledging the dimensions and anatomical variations of the pulmonary veins (PVs) may improve the outcome of the intervention. Conventional 2D transoesophageal echocardiography can only provide limited data about the dimensions of the PVs; however, 3D echocardiography can further evaluate relevant diameters and areas of the PVs, as well as their spatial relationship to surrounding structures. In previous literature data, parameters influencing the success rate of PVI have already been identified. These are the left lateral ridge, the intervenous ridge, the ostial area of the PVs and the ovality index of the ostium. Proper imaging of the PVs by 3D echocardiography is a technically challenging method. One crucial step is the collection of images. Three individual transducer positions are necessary to visualize the important structures; these are the left lateral ridge, the ostium of the PVs and the intervenous ridge of the left and right PVs. Next, 3D images are acquired and saved as digital loops. These datasets are cropped, which result in the en face views displaying spatial relationships. This step can also be employed to determine the anatomical variations of the PVs. Finally, multiplanar reconstructions are created to measure each individual parameter of the PVs.
Optimal quality and orientation of the acquired images are paramount for the appropriate assessment of PV anatomy. In the present work, we examined the 3D visibility of the PVs and the suitability of the above method in 80 patients. The aim was to provide a detailed outline of the essential steps and potential pitfalls of PV visualization and assessment with 3D echocardiography.

The dimensions of the pulmonary veins (PV) are important parameters when planning pulmonary vein isolation. 2D transoesophageal echocardiography can only provide limited data about the PVs; however, 3D echocardiography can evaluate relevant diameters and areas of the PVs, as well as their spatial relationship to surrounding structures.

The dimensions of the pulmonary veins are important parameters when planning pulmonary vein isolation (PVI), especially with the cryoballoon ablation ...

Echocardiographic Measurement of Right Ventricular Diastolic Parameters in Mouse

Diastolic dysfunction is a prominent feature of right ventricular (RV) remodeling associated with conditions of pressure overload. However, the RV diastolic function is rarely quantified in experimental studies. This might be due to technical difficulties in the visualization of the RV in the apical four-chamber view in rodents. Here we describe two positions facilitating the visualization of the apical four-chamber view in mice to assess the RV diastolic function.
The apical four-chamber view is enabled by tilting the mouse fixation platform to the left and caudally (LeCa) or to the right and cranially (RiCr). Both positions provide images of comparable quality. The results of the RV diastolic function obtained from two positions are not significantly different. Both positions are comparably easy to perform. This protocol can be incorporated into published protocols and enables detailed investigations of the RV function.

Here we describe and compare two positions for obtaining the apical four-chamber view in mice. These positions enable the quantification of the right ventricular function, provide comparable results, and can be used interchangeably.

Diastolic dysfunction is a prominent feature of right ventricular (RV) remodeling associated with conditions of pressure overload. However, the RV ...

Echocardiographic Assessment of Cardiac Anatomy and Function in Adult Rats

The use of experimental animal models has become crucial in cardiovascular science. Most studies using rodent models are focused on two-dimensional imaging to study the cardiac anatomy of the left ventricle and M-mode echo to assess its dimensions. However, this could limit a comprehensive study. Herein, we describe a protocol that allows an assessment of the heart chamber size, left ventricular function (systolic and diastolic) and valvular function. A conventional medical ultrasound machine was used in this protocol and different echo views were obtained through left parasternal, apical and suprasternal windows. In the left parasternal window, the long and short axis were acquired to analyze left chamber dimensions, right ventricle and pulmonary artery dimensions, and mitral, pulmonary and aortic valve function. The apical window allows the measurement of heart chamber dimensions and evaluation of systolic and diastolic parameters. It also allows Doppler assessment with detection and quantification of heart valve disturbances (regurgitation or stenosis). Different segments and walls of the left ventricle are visualized throughout all views. Finally, the ascending aorta, aortic arch, and descending aorta can be imaged through the suprasternal window. A combination of ultrasound imaging, Doppler flow and tissue Doppler assessment have been obtained to study cardiac morphology and function. This represents an important contribution to improve the assessment of cardiac function in adult rats with impact for research using these animal models.

A non-invasive protocol for transthoracic echocardiography assessment of cardiac anatomy and function for adult rats is presented in the current study. The heart valves, all four cardiac chambers and the ascending aorta, aortic arch and descending aorta are studied in detail.

The use of experimental animal models has become crucial in cardiovascular science. Most studies using rodent models are focused on two-dimensional ...

Biventricular Assessment of Cardiac Function and Pressure-Volume Loops by Closed-Chest Catheterization in Mice

Assessment of cardiac function is essential to conduct cardiovascular and pulmonary-vascular preclinical research. Pressure-volume loops (PV loops) generated by recording both pressure and volume during cardiac catheterization are vital when assessing both systolic and diastolic cardiac function. Left and right heart function are closely related, reflected in ventricular interdependence. Thus, recording biventricular function in the same animal is important to get a complete assessment of cardiac function. In this protocol, a closed chest approach to cardiac catheterization consistent with the way catheterization is performed in patients is adopted in mice. While challenging, the closed chest strategy is a more physiological approach, because opening the chest results in major changes in preload and afterload that create artifacts, most notably a fall in systemic blood pressure. While high-resolution echocardiography is used to assess rodents, cardiac catheterization is invaluable, particularly when assessing diastolic pressures in both ventricles.
Described here is a procedure to perform invasive, closed chest, sequential left and right ventricular pressure-volume (PV) loops in the same animal. PV loops are acquired using&#160;admittance technology with a mouse pressure-volume catheter and pressure-volume system acquisition. The procedure is described, beginning with the neck dissection, which is required to access the right jugular vein and the right carotid artery, to the insertion and positioning of the catheter, and finally the data acquisition. Then, the criteria required to ensure the acquisition of high-quality PV loops are discussed. Finally, the analysis of the left and right ventricular PV loops and the different hemodynamic parameters available to quantify systolic and diastolic ventricular function are briefly described.

Presented here is a protocol to assess biventricular heart function in mice by generating pressure-volume (PV) loops from the right and left ventricle in the same animal using closed chest catheterization. The focus is on the technical aspect of surgery and data acquisition.

Assessment of cardiac function is essential to conduct cardiovascular and pulmonary-vascular preclinical research. Pressure-volume loops (PV loops) ...

The Use of 3D Echocardiography in Surgical Planning of the Mitral Valve in Pediatric Cardiology

Mitral valve disease in pediatric cardiology is complex and can involve a combination of annular, leaflet, chordae tendineae and papillary muscle abnormalities. Transthoracic two-dimensional echocardiography (2DE) remains the primary diagnostic imaging technique utilized in pediatric surgical planning. However, given that the mitral valve is a three-dimensional (3D) structure, the addition of 3D echocardiography (3DE) to better define the mechanisms of stenosis and/or regurgitation is advantageous. Transthoracic 3DE technology has improved with advances in probe technology and ultrasound scanners, producing images with good spatial resolution and adequate temporal resolution. Specifically, the addition of pediatric 3D transducers with higher frequencies and a smaller footprint provides better 3DE imaging in children. Improved efficiency of 3DE acquisition and analysis allow 3D assessment of the mitral valve to be more easily integrated by the sonographer, the cardiologist and the surgeon in mitral valve assessment. This improvement was also made possible by the postprocessing software optimization.
In this method paper, we aim to describe the transthoracic 3DE assessment of the mitral valve in children and its use in the surgical planning of pediatric mitral valve disease. Firstly, the 3DE assessment begins by selecting the correct probe and by obtaining a view of the mitral valve. Then, the appropriate data acquisition method should be selected based on the individual patient. Next, optimization of the data set is critical in order to properly balance spatial and temporal resolution. During live scanning or following acquisition, the data set can be cropped using innovative tools that allow the user to quickly obtain an infinite number of cut planes or volumetric reconstructions. The cardiologist and surgeon can view the mitral valve en face; thus, accurately reconstructing its morphology in order to support medical or surgical planning. Finally, a review of some clinical applications is proposed, showing examples in pediatric mitral valve managements.

3D echocardiography of the mitral valve in pediatric cardiology produces full anatomic reconstructions that contribute to improved surgical management. Here, we outline a protocol for 3D acquisition and post-processing of the mitral valve in pediatric cardiology.

Mitral valve disease in pediatric cardiology is complex and can involve a combination of annular, leaflet, chordae tendineae and papillary muscle ...

ICE-Based 3D Remodeling for the Left Atrium and Pulmonary Vein

Three-Dimensional Modeling of the Left Atrium and Pulmonary Veins with a Precise Intracardiac Echocardiography Approach

Intracardiac echocardiography (ICE) is a novel tool for estimating cardiac anatomy during pulmonary vein isolation procedures, particularly the left atrium (LA) anatomy and pulmonary vein structures. ICE is widely used to establish a three-dimensional (3D) left atrial structural model during ablation procedures. However, it is unclear whether using ICE in a precise 3D modeling method can provide a more accurate left atrial 3D model and the transseptal approach. This study proposes a protocol to model the left atrium and pulmonary veins with ICE and fast anatomical mapping (FAM) catheter remodeling. It evaluates the accuracy of the models produced using the two methods through observer scoring. We included 50 patients who underwent ICE-based 3D remodeling and 45 who underwent FAM 3D remodeling based on pulmonary vein isolation procedures. The pulmonary vein antrum remodeling is estimated by comparing the antrum area acquired by remodeling and left atrial computed tomography angiography (CTA). The observer scores for the modeling in the ICE and FAM groups were 3.40 &#177; 0.81 and 3.02 &#177; 0.72 (P &#60; 0.05), respectively. The pulmonary vein antrum area obtained using the ICE- and FAM-based methods showed a correlation with the area acquired by left atrium CT. However, the 95% confidence interval bias was narrower in ICE-acquired models than in FAM-acquired models (-238 cm2 to 323 cm2 Vs. -363 cm2 to 386 cm2, respectively) using Bland-Altman analysis. Therefore, precise ICE possesses high accuracy in estimating the left atrial structure, becoming a promising approach for future cardiac structure estimation.

Author Spotlight: Advancements in Intracardiac Echocardiography for Atrial Anatomy Assessment 

Accurate intracardiac echocardiography (ICE) shows significant accuracy in estimating the left atrial structure, a prospective and promising cardiac structure estimation method. Here we propose a protocol for three-dimensional modeling of the left atrium and pulmonary veins with ICE and fast anatomical mapping (FAM) catheter remodeling.

Intracardiac echocardiography (ICE) is a novel tool for estimating cardiac anatomy during pulmonary vein isolation procedures, particularly the left ...