Real-time three-dimensional echocardiography: never before clinical efficacy looked so picturesque

International Journal of Cardiology 198 (2015) 15–21

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International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard

Review

Real-time three-dimensional echocardiography: never before clinical efficacy looked so picturesque Constantina Aggeli, Ioannis Felekos, Stelios Kastellanos, Vassiliki Panagopoulou, Evangelos Oikonomou, Eleftherios Tsiamis, Dimitris Tousoulis ⁎ 1st Cardiology Department, University of Athens Medical School, “Hippokration” Hospital, Athens, Greece

a r t i c l e

i n f o

Article history: Received 7 January 2015 Received in revised form 4 May 2015 Accepted 18 June 2015 Available online 20 June 2015 Keyword: Real-time three-dimensional echocardiography

a b s t r a c t Over the years echocardiography has served the clinical cardiologist in a variety of clinical scenarios, assisting in patient diagnostic and therapeutic managements. With the advent of novel imaging modalities we now experience the renascence of imaging. As a result, the field of cardiovascular medicine is strongly connected to imaging, which in turn requires thorough knowledge of each modality's distinct advantages and limitations. In this concise review we present up-to-date knowledge with regard to real-time three-dimensional echocardiography and its implementation in clinical practice. © 2015 Elsevier Ireland Ltd. All rights reserved.

1. Introduction Over the last fifty years conventional two-dimensional (2D) echocardiography has served as a valuable clinical adjunct for the diagnosis and management of cardiovascular disease. Being a versatile, costeffective and non-ionizing technique, echocardiography became an extension of clinical examination. However, the echocardiologist was expected to mentally reconstruct the complex structure of the heart, resulting in geometrical assumptions, which in turn could underestimate the validity of clinical findings. Three-dimensional (3D) echocardiographic (3DE) imaging represents a major innovation in cardiovascular imaging. The usefulness of 3DE has been summarized mainly in (a) the evaluation of cardiac chamber volumes and mass, avoiding geometric assumptions; (b) the assessment of regional left ventricular (LV) wall motion; (c) presentation of realistic views of heart valves; and (d) volumetric assessment of regurgitant lesions and shunts with 3D color Doppler imaging. Moreover, it has been studied for the assessment of coronary artery disease during stress imaging, as well as for the evaluation of congenital heart disease. It is worth noting that both beginners and experts benefit from 3DE, since image acquisition has been simplified and accelerated, with significant improvement in terms of inter-observer variability. Recent technological advancements have rendered this technique feasible both in the echo and the cardiac catheterization laboratory for a variety of clinical applications [1]. All these improve the way clinicians perceive cardiac structure and its spatial relationship with other organs. The use of 3DE during interventions for structural heart disease has ⁎ Corresponding author at: Vasilissis Sofias 114, TK 115 28, Hippokration Hospital, Athens, Greece. E-mail address: [email protected] (D. Tousoulis).

http://dx.doi.org/10.1016/j.ijcard.2015.06.052 0167-5273/© 2015 Elsevier Ireland Ltd. All rights reserved.

brought closer interventionists, cardiothoracic surgeons and imaging specialists. For 3DE to be efficiently implemented in routine clinical practice, a full understanding of core technical principles and a systematic approach to image acquisition and analysis are required. 1.1. Evaluation of cardiac chamber volumes An early use and probably the most common clinical application of 3DE is the measurement of cardiac chamber dimensions and volumes. A firmly established advantage of 3D imaging over cross-sectional slices of the heart is the improvement in the accuracy of the evaluation of left ventricular volumes and ejection fraction by eliminating the need for geometric modeling, which is inaccurate in the presence of aneurysms, asymmetrical ventricles, or wall motion abnormalities [2]. Some concerns have risen from the recent data on dynamic heart phantoms with optimal image quality [3–8]. Different methods of 3D volume quantification varied significantly in their accuracy and ability to track the endocardial contour through systole. Measurement using semi-automated methods appear endless robustness following manual correction, which may relate to constraints within the contour finding algorithms [9]. Whether this also holds true among the different vendors remains unknown. Three-dimensional echocardiography can depict the whole extent of the left ventricle, allowing accurate offline assessment of left ventricular mass and volumes with the implementation of dedicated software that all vendors have developed. The results have been validated against cardiac magnetic resonance imaging (MRI) which is regarded as the standard of reference for the assessment of left ventricle volumes (Table 1) and ejection fraction (EF) [10]. It has been shown that 3DE offers an improvement over conventional 2D echo, although it still underestimates volumes in comparison with cardiac magnetic resonance

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Table 1 Comparison of real time three dimensional echocardiography versus cardiac magnetic resonance/gated single photon emission computed tomography for the assessment of LV volumes. Study

Sample size

Reference modality

Feasibility rates (%)

Correlation (r)

Schmidt et al. [4] Nikitinet et al. [5] Tigheet et al. [6] Kuhlet et al. [7] Corciet et al. [8] Jenkins et al. [2] Manaertset al. [9]

25 64 64 24 30 50 32

Gated-SPECT CMR Gated-SPECT CMR CMR CMR CMR

92 100 91 100 100 100 84

0.97 0.97 0.85 0.98 0.98 0.99 0.97

CMR: Cardiac magnetic resonance. Gated-SPECT: Gated single photon emission computed tomography.

(CMR) [6]. Recently, in a multicenter study it was demonstrated that the implementation of contrast agents improves correlation with CMR and further improves inter-reader variability [11]. Thus, the better discrimination of endocardial contour offered by contrast agents combined with the visualization of the real apex by 3DE could be translated into clinical efficacy when it comes to left ventricle (LV) volumetric assessment and calculation of EF. One noteworthy limitation is the inability to analyze severely dilated ventricles when using narrow sector angles to optimize frame rates. Furthermore, the complex crescent like morphology of the right ventricle can be assessed and quantified using 3DE, providing valuable information in various disease states including congenital heart disease [11]. The intrinsic ability of 3DE imaging to directly measure right ventricular volumes without the need for geometric modeling could be expected to result in improved accuracy and reproducibility compared with traditional 2DE measurements (Table 2). Leibungut et al. [12] and van der Zwaan et al. [13] assessed the efficacy of real time 3DE to measure RV volumes and EF, using CMR as the method of reference. The investigators concluded that RT3D showed excellent correlation with cardiac MRI for the volumetric evaluation of the right ventricle, with high feasibility rates. These findings were confirmed by Grewal et al. [14] who showed that real time 3DE was accurate in measuring right ventricle (RV) volumes and EF, as compared to CMR, while, Grapsa et al. showed an excellent correlation of RV volumes in patients with pulmonary hypertension and proposed that CMR and 3DE can be used interchangeably [15]. Those studies support the hypothesis that real time 3DE is a cost-effective and reproducible method for the anatomic and functional evaluation of the right ventricle. The assessment of right atrial volumes by 3DE has also showed to have a good prognostic implication in pulmonary hypertension [16]. Moreover, 3DE can provide invaluable information about the complex geometry of the right ventricle. The display of inflow, apex, and outflow tracts is now possible by a 3DE gated wide-angled acquisition, which can then be cropped in different planes. A variety of axial cuts at the apex, mid, and base of the right ventricle can be obtained using the long axis of the left ventricle. Longitudinal cut planes can also demonstrate the right ventricle from a typical four-chamber view, coronal view, and RV inflow view [17]. Left atrium is a structure whose volume alterations have prognostic implications. However, 2D echo systematically underestimates volumes. Conversely, 3DE offers more accurate measurements as compared to MRI [18]. Recent advances on 3DE have focused on specific

software for each particular chamber resulting in more accurate evaluation of shape and function. 1.2. Assessment or regional wall-motion abnormalities Real-time 3DE has the inherent advantage of obtaining information in a full-volume pyramidal dataset within a single acquisition. This translates into clinical benefit since the operator can obtain multiple views as deemed necessary, which can illustrate regional wall motion abnormalities. This could assist in determining the extent of wall motion abnormalities as well as in ruling out artifacts frequently noted in standard imaging planes due to limited endocardial visualization. Moreover, conventional 2D echo requires significant experience in image acquisition, while 3D can provide information even by an inexperienced user [19]. The feasibility of real time 3DE and its good concordance with 2D echo on wall motion analysis for detection of inducible ischemia has been reported in several studies (Table 3) [19–25]. With the exception of few authors [24], reported sensitivity rates are high. In addition, in studies [25,26] where contrast agents were utilized, the accuracy of the 3D method to evaluate wall motion was significantly improved. The strongest point of wall-motion evaluation using 3D echo lies in the evaluation of left anterior descending disease, which is based on the inherent ability of 3D to successfully image the true left ventricular apex. Badano et al. [27], using dipyridamole as stressor, proved that 3D echocardiography is feasible for the diagnosis of CAD, based on wallmotion analysis, especially for the left anterior descending vascular bed, while in our recent study, using dobutamine as stressor, the ability of RT3D imaging to overcome left ventricular foreshortening has been reported to improve the detection of apical ischemia [19]. While all previous studies using real time 3DE applied wall motion analysis (with or without contrast agent) as a criterion for detection of CAD, myocardial perfusion analysis has been performed in only few clinical studies. The first pilot study, which documented the accuracy of live3D and full-volume myocardial contrast echo in the setting of myocardial perfusion during adenosine stress echo, was published by Abdelmoneim et al. [28] in a small number of patients, using single photon emission computed tomography (SPECT) as the gold standard for the detection of CAD. Recently, myocardial perfusion with 3DE has become possible with the implementation of contrast agents [20]. However, there are important limitations including low temporal and spatial resolutions that limit the diagnostic value of 3DE,

Table 2 Comparison of real time three dimensional echocardiography versus cardiac magnetic resonance for the assessment of RV volumes. Study

Sample size

Clinical setting

Feasibility rates

Correlation

Leibungut et al.[12]

100

Previous pulmonary valvotomy or tetralogy of Fallot repair Congenital heart disease Congenital heart disease

88

0.84

84 81

0.88 0.93

Grewal et al. [14] van der Zwaan et al. [13]

25 62

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Table 3 Feasibility and diagnostic values of real time three dimensional echocardiography during stress echo. Study

Sample size

Stressor

Feasibility 3D (%) at stress

CAD detection criterion

Reference method

Sensitivity (%)

Specificity (%)

Aggeli et al. [19] Aggeli et al.a [20] Takeuchi et al. [24] Peteiro et al. [21] Matsumura et al.[22] Ahmad et al.[23]

56 60 78 84 56 90

Dobutamine Adenosine Dobutamine Treadmill test Dobutamine Dobutamine

n/a 90–92 97 92 89

WMA WMA + perfusion defect WMA WMA WMA WMA

Angiography Angiography 2D Echo Angiography SPECT Angiography

78 98 58 78 86 88

89 45 75 73 80 88

CAD = coronary artery disease; WMA = wall-motion abnormalities. a Diagnostic values refer to combined assessment.

especially when the cardiac muscle is functioning at increased heart rates. These limitations are expected to be overcome with evolution in transducer technology. 1.3. Regional left ventricular function Real-time three-dimensional echo has emerged as a valuable tool for the assessment of regional and global left ventricular function. Bhan et al. [29] were the first to introduce the dyssynchrony index, which could predict myocardial dyssynchrony and respond to cardiac resynchronization therapy. More recently, the evolution of three-dimensional speckle-tracking echocardiography (3D-STE) has rendered the assessment of myocardial deformation in all three spatial dimensions feasible [30]. Area strain (AS), an innovative feature of 3D-STE, integrates both longitudinal (LS) and circumferential strain (CS) and reflects regional changes in endocardial surface area throughout the cardiac cycle, thus representing a faster, reproducible and more comprehensive parameter in evaluation of myocardial function. Importantly, normal values for 3-dimensional strain have also recently been published using one vendor for all age groups, which is important for the clinical routine [31]. Smith et al. [32] recently showed that AS of the right ventricle is related to clinical outcomes in patients with pulmonary hypertension. 2D-STE strain analysis on the other hand, is subject to the out-ofplane motion of the speckles during the cardiac cycle, and as a result ignores the actual three-dimensional myocardial movement. There are a number of limitations using 3D-STE, including high dependency on image quality, which in turn is subject to relatively low temporal resolution and low frame rate. All these factors may lead to miscorrelation between frames, negatively affecting the accuracy of obtained data. Moreover, currently available 3D speckle-tracking echocardiographic methods are based on different algorithms, which introduce substantial differences between them and make them non-interchangeable with each other [33]. 1.4. Assessment and management of heart valve disease One of the most challenging clinical tasks is the evaluation of cardiac valve morphology and function. An accurate assessment of valve disease has important implications in patient management. The rationale of implementing novel technologies of advanced matrix transducers lies on the fact that 3DE potentially provides more accurate morphological and functional information, along with better definition of spatial relationships. It gives detailed data on definitive anatomical characterization (number of cusps or leaflets), and localization, enables planimetry of valve orifice and offers exact information on prosthetic valves [33]. Real-time 3DE can guide the interventionist both in patient selection and during the transcatheter valve implantation. In the recently published recommendations for the use of 3DE in the evaluation of cardiac valve, the additive value of 3DE has been emphasized, especially with regard to aortic and mitral valve diseases [33]. On the contrary, there is a great paucity of data for the assessment of tricuspid and pulmonic valves.

1.4.1. Aortic valve Aortic valve is a complex structure, consisting of the left ventricular outflow tract, the annulus, the Valsalva sinuses, the aortic cusps and the sinotubular junction [34,35]. As a result, it is important that accurate measurements of the respective anatomic landmarks are provided for the better definition of aortic valve pathology. Left ventricular outflow tract has an elliptical form, making accurate measurements often difficult [36]. Three-dimensional echo offers information for the longitudinal and transverse remodeling of the aortic root in aortic stenosis. It also allows better spatial orientation, thus offering a better approximation of the true opening, which in turn enables more accurate planimetry [37]. Three-dimensional measurements are also more reproducible than conventional 2D [36]. It should be noted though, that there is a lack of reference measurements. During transcatheter aortic valve implantation (TAVI), the decision regarding the size of the TAVI valve may not always be easy due to the relationship between the complex aortic valve anatomy and the aortic root-LV outflow tract. With 3DE it is now possible to measure the exact annulus size, avoiding any geometrical assumptions involving annular shape and geometry [36]. Thus, a more accurate valve size can be selected for each patient, avoiding complications related to valve underor oversizing [37,38]. The location of the coronary ostia and their distance from the valve annulus is also important particularly for the Edwards SAPIEN valve [39]. A minimum distance of 10–11 mm between the aortic annulus and the coronary ostium (particularly the left) is recommended. While multi-slice CT can provide this measurement, full volume 3DE can also produce a similar assessment particularly when extensive calcifications may be present [39–41]. Furthermore 3DE can aid in the positioning and deployment of the prosthetic valve across the annulus and instantly assess if any degree of aortic regurgitation is present.

1.4.2. Mitral valve Key components of the mitral apparatus are the mitral annulus (MA), the valve leaflets, the chordae tendineae, and the LV wall with its attached papillary muscles (Videos 1 and 2). Valve function is dependent on the integrity and harmonious interplay of these components. Valve area can be estimated with precision by 3D, which seems to offer better agreement as compared to 2D orifice area and pressure half-time methods [42]. The three-dimensional zoom acquisition mode allows for the highest temporal and spatial resolutions, is suitable for the description of anatomic details of MV leaflets, while full-volume acquisition is required when mitral apparatus needs to be assessed at its entity. In addition, novel software quantification has made the evaluation of regurgitation feasible with the off-line reconstruction of 3D regurgitant jet [43]. With the advent of 3D color Doppler volumetric data acquisition, we now have the ability to determine the true cross sectional area of the vena contracta, overcoming the geometric limitations of 2D color Doppler when encountering multiple or eccentric jets [44]. 3DE plays an integral role for the transcatheter treatment of mitral valve regurgitation with the mitral clip device. The ability to illustrate the morphology of the complex mitral apparatus from the left atrial

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view (surgical view) has vastly improved our understanding of mitral valve pathology. The distortion of spatial relationship between the LV and the mitral valve apparatus results in functional or ischemic regurgitation. With the development of transcatheter treatment of mitral regurgitation using mitral clips, a though understanding of the mechanism of mitral regurgitation is achieved using 3-dimensional echocardiography. Displacement of the papillary muscle away from the anterior leaflet occurs with tethering of the posterior leaflet in ischemic mitral regurgitation. In contrast, the apical displacement of the coaptation or increase in tenting volume caused by annular dilation leading to a decrease in the mitral valve coaptation area is thought to be the underlying mechanism of mitral regurgitation in dilated cardiomyopathy [45]. Off-line software can provide quantification of leaflet coaptation, thus overcoming the limitation of conventional Doppler velocimetry, especial for eccentric regurgitant jets. Moreover, the eccentricity of the regurgitant jet can be deferred, which is an important step during patient selection stage and evaluation if there is sufficient tissue for mechanical caption of the valve. Intra-procedurally 3DE is very helpful during trans-septal puncture and facilitates catheter orientation towards mitral valve apparatus [46]. The efficacy of new mitral valve implantation techniques, such as the trans-apical approach has not been extensively studied yet. Therefore, the role of 3DE during this procedure remains to be clarified. Furthermore 3DE offers valuable diagnostic and prognostic information for endocarditis. The volume of vegetation has prognostic value for embolic events in patients with endocarditis and guides the treatment decision when valve surgery is contemplated. Three-dimensional echo offers the ability to accurately measure vegetation dimensions [47]. Occasionally, especially in the presence of large masses, the exact definition of the anatomic relationship between the vegetation, the prosthesis, and adjacent intracardiac structures can be extremely challenging. Three-dimensional (3D) TEE is able to define more accurately the intracardiac anatomy, morphology of the mass, and residual effective valve orifice, just in one echocardiographic view. The ability to reconstruct and the flexibility to crop full-volume data sets offer the surgeon a virtual but realistic preoperative perspective of the disease process, providing correlations with pathologic anatomy, invaluable for surgical planning [47]. It should be noted though that the implementation of 3DE in the diagnostic assessment of infective endocarditis has not been extensively studied yet. 1.5. Structural heart disease Real-time 3DE has become an indispensable resident in the cardiac catheterization laboratory, as it is applicable to a wide range of structural interventions often guided by echocardiography. Three-dimensional transesophageal echo (3D TOE) has been shown to provide additional insight into the anatomical, morphological and hemodynamic assessment of structural heart disease [48]. It has become the imaging modality of choice for many interventionists, and in many cases it serves as the operator's “eyes”to evaluate, guide, and assess the results of procedures in the catheterization laboratory. The unique structural information obtained offers the potential for shorter and safer interventional procedures, with a higher rate of technical success, thus improving patient outcomes [49]. 1.6. Left atrial appendage closure Left atrial appendage (LAA) closure has been proposed as an alternative method of embolic protection in patients with atrial fibrillation who cannot tolerate, or have contraindications to anticoagulation therapy. Transesophageal echocardiography can assist in proper patient selection and identify patients with thrombotic material prior the procedure. Three-dimensional echocardiography offers incremental information, by defining the anatomy of the LAA, especially when anatomic variations, such as multi-lobar appendage, are anticipated. Moreover, more accurate measurements can be provided, aiding in proper device

selection. During the procedure, 3DE can assist with transeptal puncture and guide the accurate device deployment [50]. 1.7. Closure of paravalvular leaks and intracardiac shunts Two-dimensional TOE has become an essential and integral guiding tool during interventional device closure, but it is limited in its ability to detect the position of a catheter or a device relative to its surrounding environment due to only two spatial dimensions. Even in experienced operators, numerous cut planes are necessary in order to mentally reconstruct the anatomical setting. The application of 3DE was shown to be feasible for the accurate determination of ASD size, shape, rims guiding patient and device selection and also demonstrated a decrease in fluoroscopy time (Fig. 2 panel A). Real-time 3D TOE provides a unique imaging modality for the guidance of atrial septal defects and patent foramen oval closures, giving fast and complete information about the appropriate position of the device in its surrounding environment and assesses post-operatively the firm and complete implantation of the device [51]. (See Fig. 1.) In paravalvular leak closure the main issue is to adequately visualize the leak(s) and assess its spatial relationship with surrounding structures (Video 3). Real-time 3DE can offer enhanced appreciation of the complex anatomy and better locate and size the leak. It can also offer guidance during catheter steering and manipulation through the defect without the need for time-intensive offline reconstruction. In addition, 3DE can be used immediately post-closure (Fig. 2 panel B) to assess device stability and interaction with surrounding structures [52]. The implementation of 3DE in percutaneous interventions can be sometimes problematic, mainly due to artifacts and drop outs. Dropout artifacts could be misdiagnosed as holes, while variations in gain setting could lead in overestimation of orifice areas. Reverberations tend to lengthen the size of the catheter, which could make catheter manipulation problematic, while stitching artifacts reduce image quality, rendering image analysis difficult [53]. 1.8. Clinical implications–future directions Three-dimensional echocardiography has gone a long way since 2003, when the first matrix array transducer was developed, with a variety of clinical applications. For the clinician the question remains: could it truly make the difference in clinical practice? Ruddox et al. [54] tried to answer this complex question through a recent metaanalysis from 2007 to 2012. The authors concluded that 3D was superior for the assessment of LV volumes and EF, provided the patient is in sinus rhythm. For a valve disease, however, data are somehow conflicting, rendering the implementation of 3D not a necessity. Nevertheless, more studies are required in order to redefine its proper position in the clinical armamentarium. 1.9. Evaluation of atherosclerosis Research and clinical interest has recently focused on the 3D evaluation of atherosclerosis of the carotid artery and aorta. Novel modalities have rendered the volumetric assessment of atheromatous burden a reality, enabling the quantification of atherosclerosis. It has been reported by several studies that the atherosclerosis of the thoracic aorta is a powerful marker for generalized atherosclerosis, including coronary vessels, carotid and peripheral arteries. Aortic arch atherosclerosis is even regarded as a risk factor for ischemic stroke [55,56]. Therefore, various modalities have been integrated into clinical practice for the evaluation of atheromatosis of the thoracic aorta, including MRI and CT, with TEE considered as the reference standard [57]. In a recently published study involving 17 familial hypercholesterolemia patients, we have shown that it is feasible to quantify the atheromatous volume of the thoracic aorta, by measuring the volume of atheromatous plaques using real-time 3DE [58].

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Fig. 1. Elliptically-shaped atrial septal defect (a) before and (b) after closure with umbrella device.

It would appear that the carotid bulb plaque quantification by 3D automated acquisition may be an effective noninvasive method to rule out significant coronary artery disease (CAD), suggesting the important role of plaque volume [59]. The application of 3D plaque quantification may be useful in both assessment for angiographic CAD and long-term risk stratification, representing different entities. The evaluation of the extension of atherosclerotic disease plays a crucial role in prognosis on various groups of patients with cardiovascular disease. Is it really a barometer before the storm? Compared with carotid intima media thickness (CIMT), carotid artery plaque may be a strong indicator of disease elsewhere in the vascular tree, including the coronary arteries. Plaque has a stronger association than CIMT with coronary atherosclerosis as the two represent biologically distinct phenomena. CIMT is mainly a result of hypertensive thickening of smooth muscles in the media layer, but atherosclerosis is, in fact, a process involving the entity of the arterial wall. Thus plaque volume and area, which represent focal increases in arterial wall thickness, are more likely to represent regions of atherosclerosis rather than medial hypertrophy [60]. Analysis of plaque texture, use of contrast, assessment of plaque calcification and synergism with other imaging, plasma, or genetic biomarkers are all important areas requiring greater study. 1.10. General limitations Real-time 3DE is a method with inherent limitations, which should be acknowledged, for the implementation in clinical practice to be more accurate and efficacious. First of all the temporal and spatial

resolutions of the technique is lower as compared to MRI. This is in turn results in many artifacts during image acquisition, rendering pathology assessment erroneous and difficult at times. This is true for applications such as Doppler and stress echo. Moreover, the delineation of epicardial contours can be challenging, affecting the accuracy of cardiac mass measurements. Developments in transducer technology will definitely improve 3DE frame rates, alleviating the aforementioned limitations. Another limitation is the time needed to perform off-line analysis for chamber quantification, potentially affecting the workflow of busy echo departments. However, this limitation tends to be overcome with the development of more sophisticated software algorithms.

2. Conclusion Real-time three-dimensional echocardiography is here to stay and offers a more comprehensive insight into structural heart disease compared to 2D. It vastly improves and expands the diagnostic capabilities of cardiac ultrasound. It allows visualization of cardiac anatomy and pathology in a format that is readily appreciated by cardiac surgeons and interventional cardiologists. It is essential in guiding and assessing the results of interventional procedures. This will have a great impact on the way physicians treat their patients as it makes diagnostic assessment more accurate and minimizes errors during the delivery of transcatheter interventions. Future improvements in transducer technology, however, are important in order to improve image quality and increase volume rates.

Fig. 2. Severe atheromatosis of ascending thoracic aorta (a) and stented graft in ascending thoracic aorta (b).

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Supplementary data to this article can be found online at http://dx. doi.org/10.1016/j.ijcard.2015.06.052. Conflict of interest None. Sources of funding None declared. References [1] C. Aggeli, M. Bellamy, N. Sutaria, C. Stefanadis, P. Nihoyannopoulos, Real-time 3dimensional transoesophageal echocardiography: an indispensable resident in the catheter laboratory, Hell. J. Cardiol. 53 (2012) 1–5. [2] C. Jenkins, K. Bricknell, J. Chan, L. Hanekom, T.H. Marwick, Comparison of two- and three-dimensional echocardiography with sequential magnetic resonance imaging for evaluating left ventricular volume and ejection fraction over time in patients with healed myocardial infarction, Am. J. Cardiol. 99 (2007) 300–306. [3] M.A. Schmidt, C.J. Ohazama, K.O. Agyeman, et al., Real-time three-dimensional echocardiography for measurement of left ventricular volumes, Am. J. Cardiol. 84 (1999) 1434–1439. [4] N.P. Nikitin, C. Constantin, P.H. Loh, et al., New generation 3-dimensional echocardiography for left ventricular volumetric and functional measurements: comparison with cardiac magnetic resonance, Eur. J. Echocardiogr. 7 (2006) 365–372. [5] D.A. Tighe, M. Rosetti, C.S. Vinch, et al., Influence of image quality on the accuracy of real time three-dimensional echocardiography to measure left ventricular volumes in unselected patients: a comparison with gated-SPECT imaging, Echocardiography 24 (2007) 1073–1080. [6] H.P. Kuhl, M. Schreckenberg, D. Rulands, et al., High-resolution transthoracic realtime three-dimensional echocardiography: quantitation of cardiac volumes and function using semi-automatic border detection and comparison with cardiac magnetic resonance imaging, J. Am. Coll. Cardiol. 43 (2004) 2083–2090. [7] C. Corsi, R.M. Lang, F. Veronesi, et al., Volumetric quantification of global and regional left ventricular function from real-time three-dimensional echocardiographic images, Circulation 112 (2005) 1161–1170. [8] H.F. Mannaerts, J.A. Van Der Heide, O. Kamp, et al., Quantification of left ventricular volumes and ejection fraction using freehand transthoracic threedimensional echocardiography: comparison with magnetic resonance imaging, J. Am. Soc. Echocardiogr. 16 (2003) 101–109. [9] P.W. Wood, P.H. Gibson, H. Becher, Three-dimensional echocardiography in a dynamic heart phantom: comparison of five different methods to measure chamber volume using a commercially available software, Echo Res. Pract. 1 (2014) 51–60. [10] V. Mor-Avi, L. Sugeng, R.M. Lang, Real-time 3-dimensional echocardiography: an integral component of the routine echocardiographic examination in adult patients? Circulation 119 (2009) 314–329. [11] R. Hoffmann, G. Barletta, S. von Bardeleben, et al., Analysis of left ventricular volumes and function: a multicenter comparison of cardiac magnetic resonance imaging, cine ventriculography, and unenhanced and contrast-enhanced twodimensional and three-dimensional echocardiography, J. Am. Soc. Echocardiogr. 27 (2014) 292–301. [12] G. Leibundgut, A. Rohner, L. Grize, et al., Dynamic assessment of right ventricular volumes and function by real-time three-dimensional echocardiography: a comparison study with magnetic resonance imaging in 100 adult patients, J. Am. Soc. Echocardiogr. 23 (2010) 116–126. [13] H. van der Zwaan, W. Helbing, J. McGhie, et al., Clinical value of real-time threedimensional echocardiography for right ventricular quantification in congenital heart disease: validation with cardiac magnetic resonance imaging, J. Am. Soc. Echocardiogr. 23 (2010) 134–140. [14] J. Grewal, D. Majdalany, I. Syed, P. Pellikka, C.A. Warnes, Three-dimensional echocardiographic assessment of right ventricular volume and function in adult patients with congenital heart disease: comparison with magnetic resonance imaging, J. Am. Soc. Echocardiogr. 23 (2010) 127–133. [15] J. Grapsa, J.S. Gibbs, D. Dawson, et al., Morphologic and functional remodeling of the right ventricle in pulmonary hypertension by real time three dimensional echocardiography, Am. J. Cardiol. 109 (2012) 906–913. [16] J. Grapsa, J.S. Gibbs, I.Z. Cabrita, et al., The association of clinical outcome with right atrial and ventricular remodelling in patients with pulmonary arterial hypertension: study with real-time three-dimensional echocardiography, Eur. Heart J. Cardiovasc. Imaging 13 (2012) 666–672. [17] R.M. Lang, L.P. Badano, W. Tsang, et al., EAE/ASE recommendations for image acquisition and display using three-dimensional echocardiography, Eur. Heart J. Cardiovasc. Imaging 13 (1) (2012 Jan) 1–46. [18] C. Aggeli, I. Felekos, E. Poulidakis, A. Aggelis, D. Tousoulis, C. Stefanadis, Quantitative analysis of left atrial function in asymptomatic patients with b-thalassemia major using real-time three-dimensional echocardiography, Cardiovasc. Ultrasound 9 (2011) 38. [19] C. Aggeli, G. Giannopoulos, P. Misovoulos, et al., Real-time three-dimensional dobutamine stress echocardiography for coronary artery disease diagnosis: validation with coronary angiography, Heart 93 (2007) 672–675.

[20] C. Aggeli, I. Felekos, G. Roussakis, et al., Value of real-time three-dimensional adenosine stress contrast echocardiography in patients with known or suspected coronary artery disease, Eur. J. Echocardiogr. 12 (2011) 648–655. [21] J. Peteiro, P. Pinon, R. Perez, L. Monserrat, D. Perez, A. Castro-Beiras, Comparison of 2- and 3-dimensional exercise echocardiography for the detection of coronary artery disease, J. Am. Soc. Echocardiogr. 20 (2007) 959–967. [22] Y. Matsumura, T. Hozumi, K. Arai, et al., Non-invasive assessment of myocardial ischaemia using new real-time three-dimensional dobutamine stress echocardiography: comparison with conventional two-dimensional methods, Eur. Heart J. 26 (2005) 1625–1632. [23] M. Ahmad, T. Xie, M. McCulloch, G. Abreo, M. Runge, Real-time three-dimensional dobutamine stress echocardiography in assessment stress echocardiography in assessment of ischemia: comparison with two-dimensional dobutamine stress echocardiography, J. Am. Coll. Cardiol. 37 (2001) 1303–1309. [24] M. Takeuchi, S. Otani, L. Weinert, K.T. Spencer, R.M. Lang, Comparison of contrastenhanced real-time live 3-dimensional dobutamine stress echocardiography with contrast 2-dimensional echocardiography for detecting stress-induced wallmotion abnormalities, J. Am. Soc. Echocardiogr. 19 (2006) 294–299. [25] T. Pulerwitz, K. Hirata, Y. Abe, et al., Feasibility of using a real-time 3-dimensional technique for contrast dobutamine stress echocardiography, J. Am. Soc. Echocardiogr. 19 (2006) 540–545. [26] B.J. Krenning, A. Nemes, O.I. Soliman, et al., Contrast-enhanced three-dimensional dobutamine stress echocardiography: between Scylla and Charybdis? Eur. J. Echocardiogr. 9 (2008) 757–760. [27] L.P. Badano, D. Muraru, F. Rigo, et al., High volume-rate three-dimensional stress echocardiography to assess inducible myocardial ischemia: a feasibility study, J. Am. Soc. Echocardiogr. 23 (2010) 628–635. [28] S.S. Abdelmoneim, M. Bernier, A. Dhoble, et al., Assessment of myocardial perfusion during adenosine stress using real time three-dimensional and two-dimensional myocardial contrast echocardiography: comparison with single-photon emission computed tomography, Echocardiography 27 (2010) 421–429. [29] A. Bhan, S. Kapetanakis, M.J. Monaghan, Three-dimensional echocardiography, Heart 96 (2010) 153–163. [30] Y. Seo, T. Ishizu, A. Atsumi, R. Kawamura, K. Aonuma, Three-dimensional speckle tracking echocardiography, Circ. J. 78 (2014) 1290–1301. [31] S.A. Kleijn, N.G. Pandian, J.D. Thomas, et al., Normal reference values of left ventricular strain using three-dimensional speckle tracking echocardiography: results from a multicentre study, Eur. Heart J. Cardiovasc. Imaging 16 (2015) 410–416. [32] B.C. Smith, G. Dobson, D. Dawson, A. Charalampopoulos, J. Grapsa, P. Nihoyannopoulos, Three-dimensional speckle tracking of the right ventricle: toward optimal quantification of right ventricular dysfunction in pulmonary hypertension, J. Am. Coll. Cardiol. 64 (2014) 41–51. [33] S.A. Luis, A. Yamada, B.K. Khandheria, et al., Use of three-dimensional speckletracking echocardiography for quantitative assessment of global left ventricular function: a comparative study to three-dimensional echocardiography, J. Am. Soc. Echocardiogr. 27 (2014) 285–291. [34] M.H. Yacoub, P.J. Kilner, E.J. Birks, M. Misfeld, The aortic outflow and root: a tale of dynamism and crosstalk, Ann. Thorac. Surg. 68 (1999) S37–S43. [35] R.H. Anderson, Clinical anatomy of the aortic root, Heart 84 (2000) 670–673. [36] L. Perez de Isla, J. Zamorano, R. Perez de la Yglesia, et al., Quantification of aortic valve area using three-dimensional echocardiography, Rev. Esp. Cardiol. 61 (2008) 494–500. [37] J.J. Bax, V. Delgado, V. Bapat, et al., Open issues in transcatheter aortic valve implantation. Part 1: patient selection and treatment strategy for transcatheter aortic valve implantation, Eur. Heart J. 35 (2014) 2627–2638. [38] A.C. Ng, V. Delgado, F. van der Kley, et al., Comparison of aortic root dimensions and geometries before and after transcatheter aortic valve implantation by 2- and 3dimensional transesophageal echocardiography and multislice computed tomography, Circ. Cardiovasc. Imaging 3 (2010) 94–102. [39] L.F. Tops, D.A. Wood, V. Delgado, et al., Noninvasive evaluation of the aortic root with multislice computed tomography implications for transcatheter aortic valve replacement, JACC Cardiovasc. Imaging 1 (2008) 321–330. [40] G. Tamborini, L. Fusini, P. Gripari, et al., Feasibility and accuracy of 3DTEE versus CT for the evaluation of aortic valve annulus to left main ostium distance before transcatheter aortic valve implantation, JACC Cardiovasc. Imaging 5 (2012) 579–588. [41] D.R. Holmes Jr., M.J. Mack, S. Kaul, et al., 2012 ACCF/AATS/SCAI/STS expert consensus document on transcatheter aortic valve replacement: developed in collaboration with the American Heart Association, American Society of Echocardiography, European Association for Cardio-Thoracic Surgery, Heart Failure Society of America, Mended Hearts, Society of Cardiovascular Anesthesiologists, Society of Cardiovascular Computed Tomography, and Society for Cardiovascular Magnetic Resonance, Ann. Thorac. Surg. 93 (2012) 1340–1395. [42] D. Maragiannis, S.H. Little, Quantification of mitral valve regurgitation: new solutions provided by 3D echocardiography, Curr. Cardiol. Rep. 15 (2013) 384. [43] J.L. Zamorano, A. Goncalves, Three dimensional echocardiography for quantification of valvular heart disease, Heart 99 (2013) 811–818. [44] D. Maragiannis, S.H. Little, 3D vena contracta area to quantify severity of mitral regurgitation: a practical new tool? Hell. J. Cardiol. 54 (2013) 448–454. [45] R.M. Lang, W. Tsang, L. Weinert, V. Mor-Avi, S. Chandra, Valvular heart disease. The value of 3-dimensional echocardiography, J. Am. Coll. Cardiol. 58 (2011) 1933–1944. [46] A. Goncalves, P. Marcos-Alberca, J.L. Zamorano, Echocardiography: guidance during valve implantation, EuroIntervention 6 Suppl. G (2010) G14–G19. [47] S. Bhattacharyya, T. Bahrami, S. Rahman-Haley, Comprehensive assessment of complications of infective endocarditis by 3D transesophageal echocardiography, Int. J. Cardiol. 174 (2014) e87–e89.

C. Aggeli et al. / International Journal of Cardiology 198 (2015) 15–21 [48] K.L. Chan, X. Liu, K.J. Ascah, L.M. Beauchesne, I.G. Burwash, Comparison of real-time 3-dimensional echocardiography with conventional 2-dimensional echocardiography in the assessment of structural heart disease, J. Am. Soc. Echocardiogr. 17 (2004) 976–980. [49] T. Taskesen, S.L. Goldberg, E.A. Gill, Role of three-dimensional echocardiography in management of acquired intracardiac shunts, Echocardiography 31 (2014) E250–E253. [50] D. Maragiannis, S.H. Little, Interventional imaging: the role of echocardiography, Methodist Debakey Cardiovasc. J. 10 (3) (2014) 172–177. [51] R. McKendrick, C.Y. Owada, Real-time 3D echocardiography-guided transcatheter device closure of atrial septal defects, Catheter. Cardiovasc. Interv. 65 (2005) 442–446 (discussion 447). [52] M.S. Kim, I.P. Casserly, J.A. Garcia, A.J. Klein, E.E. Salcedo, J.D. Carroll, Percutaneous transcatheter closure of prosthetic mitral paravalvular leaks: are we there yet? JACC Cardiovasc. Interv. 2 (2009) 81–90. [53] F.F. Faletra, A. Ramamurthi, M.C. Dequarti, L.A. Leo, T. Moccetti, N. Pandian, Artifacts in three-dimensional transesophageal echocardiography, J. Am. Soc. Echocardiogr. 27 (2014) 453–462. [54] V. Ruddox, M. Mathisen, M. Baekkevar, E. Aune, T. Edvardsen, J.E. Otterstad, Is 3D echocardiography superior to 2D echocardiography in general practice? A

[55] [56]

[57]

[58]

[59] [60]

21

systematic review of studies published between 2007 and 2012, Int. J. Cardiol. 168 (2013) 1306–1315. A. Cohen, Atherosclerosis of the thoracic aorta further characterization for higher risk of vascular events, J. Am. Coll. Cardiol. 52 (2008) 862–864. S. Sen, A. Hinderliter, P.K. Sen, et al., Aortic arch atheroma progression and recurrent vascular events in patients with stroke or transient ischemic attack, Circulation 116 (2007) 928–935. Z.A. Fayad, T. Nahar, J.T. Fallon, et al., In vivo magnetic resonance evaluation of atherosclerotic plaques in the human thoracic aorta: a comparison with transesophageal echocardiography, Circulation 101 (2000) 2503–2509. C. Aggeli, C. Kazazaki, I. Felekos, et al., Role of real time-3D transesophageal echocardiography in evaluating the atheromatous burden of thoracic aorta in patients with heterozygous familial hypercholesterolemia: Comparison with 2D transesophageal study, Int. J. Cardiol. 150 (2011) 92–93. A.M. Johri, J.D. Spence, Barometer in the storm — carotid artery plaque quantified by three-dimensional ultrasound, J. Am. Soc. Echocardiogr. 26 (2013) A20. A.M. Johri, D.W. Chitty, M. Matangi, et al., Can carotid bulb plaque assessment rule out significant coronary artery disease? A comparison of plaque quantification by two- and three-dimensional ultrasound, J. Am. Soc. Echocardiogr. 26 (2013) 86–95.