• Users Online: 440
  • Print this page
  • Email this page


 
 Table of Contents  
REVIEW ARTICLE
Year : 2019  |  Volume : 3  |  Issue : 3  |  Page : 163-176

Three-Dimensional Echo and Three-Dimensional Transesophageal Echocardiography for Mitral Valve Disease


Department of Non-Invasive Cardiology, Fortis Escorts Heart Institute, New Delhi, India

Date of Submission16-Dec-2018
Date of Decision08-Jan-2019
Date of Acceptance22-Feb-2019
Date of Web Publication18-Dec-2019

Correspondence Address:
Ashok Kumar Omar
Fortis Escorts Heart Institute, Okhla Road, New Delhi - 110 025
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jiae.jiae_50_18

Rights and Permissions
  Abstract 

Three-dimensional (3D) echocardiography is one of the greatest technologies, which has a significant contribution in the field of valvular heart disease, especially after the development of real-time (RT) capability in transthoracic as well as transesophageal imaging during the past decade. RT 3D transesophageal echo has provided a simplified imaging tool for the anatomy of mitral valve (MV), including the MV annulus, leaflets, and subvalvular apparatus. Three scallops of anterior and posterior leaflets are easily recognized. This helps in localizing the MV abnormality, for example, MV prolapse and flail MV. This also helps in localizing the mitral regurgitation (MR). Even the quantification of MR has also seen a novel understanding of RT 3D planimetry of MR jet, which is possible by newer machines. Commissural inequality and calcification is well identified, and it helps in choosing the cases for percutaneous balloon mitral valvuloplasty. More recently, this technology with RT 3D transesophageal echocardiography has found a role in interventional procedure, for example, balloon mitral valvuloplasty, paravalvular leak closure, and edge-to-edge (MitraClip) repair of degenerative MV.

Keywords: Mitral valve, three-dimensional echo, three-dimensional transesophageal echocardiography


How to cite this article:
Omar AK, Sharma V, Kumar V, Mustaqueem A, Shrivastava S. Three-Dimensional Echo and Three-Dimensional Transesophageal Echocardiography for Mitral Valve Disease. J Indian Acad Echocardiogr Cardiovasc Imaging 2019;3:163-76

How to cite this URL:
Omar AK, Sharma V, Kumar V, Mustaqueem A, Shrivastava S. Three-Dimensional Echo and Three-Dimensional Transesophageal Echocardiography for Mitral Valve Disease. J Indian Acad Echocardiogr Cardiovasc Imaging [serial online] 2019 [cited 2020 Jun 5];3:163-76. Available from: http://www.jiaecho.org/text.asp?2019/3/3/163/273301


  Introduction Top


Ease of acquisition with rapid online display of three-dimensional (3D) images has allowed real-time (RT) 3D transesophageal echocardiography (TEE) to be used extensively for evaluating the valvular morphology. The moving, dynamic object is considered 4D (time is referred as 4th dimension). RT 3D echocardiography used special probes with matrix array transducers containing 3000 crystals. They acquire data in the form of volume instead of planar images.[1],[2]

3D TEE probes available now have the capability of performing the standard function of 2D probes, m-mode, 2D imaging and pulse wave, continuous wave Doppler, color Doppler, and 3D image acquisition [Figure 1] and [Figure 2]. 3D technology is evolving to produce larger 3D volumes in RT with better temporal and spatial resolution. Because this technology is user-friendly, we can easily acquire transthoracic and TEE by simply pushing single 3D imaging button.
Figure 1: Three-dimensional echocardiography concept of three-dimensional echo matrix array transducer

Click here to view
Figure 2: X5-1: all in one transducer 4VD two-dimensional imaging two-dimensional color Doppler PW and CW Doppler three-dimensional imaging live three-dimensional imaging and color live three-dimensional zoom full volume imaging and color. A miniaturized matrix-type transducer that allows user to perform two-dimensional and three-dimensional echocardiographic imaging without switching transducers

Click here to view


3D imaging is done in various modes, namely, live, zoom, full volume (FV), and color Doppler mode. Different 3D modes are used for imaging different cardiac structures, which is balancing between spatial and temporal resolution. Zoom mode is a selection of small 3D pyramidal view of the region of interest like mitral valve (MV) [Table 1].[1]
Table 1: Modes of three-dimensional echo acquisition

Click here to view


It helps improve temporal resolution and quality of the image.[3] While FV acquisition has a large 3D pyramidal volume, several (3-7) subvolumes are acquired in different beats and stitched together. Color Doppler FV is gated acquisition of a small 3D pyramidal volume with superimposed color flow. The current technology creates only a small 3D color images at low frame rate.

Similar to 2D TEE, structures closure to TEE probe are easily imaged in 3D. Image optimization by adjustment of gain, compression, brightness, and smoothness are adjus[Table 3]D imaging tools. One should be aware of image artifacts which are caused by arrhythmias, electrocautery probe movement, etc. Dropouts are also a big problem; however, they can be reduced by appropriate gain.

3D volume can be cropped, rotated, and displayed from different perspectives. Easily recognized aortic valve is often used as a reference to orient the 3D volume to provide a surgeon's perspective. 3D echo has proven to be superior to 2D echo for the assessment of the left ventricle and MV. Single heartbeat large volume acquisition is not available; however, when the volume of interest increases in size, image quality is compromised in terms of spatial and temporal resolution. The single beat acquisition mode is useful for studying single structure as the region of interest like MV.

Time taken for offline analysis limited previously, clinical utility of 3D echo. However, with the introduction of current 3D TEE RT imaging, quality, acquisition, and analysis of data sets can be performed online within seconds. Imaging in 3D provides a clear appreciation of the real shape of cardiac structures and spatial relationships between them. Evaluation of valvular heart disease from diagnosis to planning the intervention requires identifying the valve pathology and assessment of consequent cardiac dysfunction.


  Three-Dimensional Optimization Top


Low gain settings result in echo dropout with potential to artificially eliminate anatomic structures that cannot be recovered during postprocessing. While the excess gain, there is decreased resolution and loss of 3D perspective. As a general rule, both gain and compression settings are set at midrange (50 units) and optimized with slightly higher gain (TGC) to enable the greatest flexibility with postprocessing.


  Mitral Valve Top


RT 3D TEE provides excellent images of MV geometry. Although in majority of patients with MV disease, comprehensive 2D imaging and Doppler echocardiography are sufficient, improved imaging through 3D transthoracic and 3D RT TEE has made vast contributions in understanding MV disease.[4]

Assessment of the morphology of MV by 2D echo requires to obtain multiple views through all segments of the two leaflets. This requires a considerable amount of experience and expertise. Mental reconstruction of all views in different angles can lead to recognize the defect in particular segments of leaflets. 3D transthoracic echocardiography (TTE) can provide a rapid overview of MV using en face or surgical view from the left atrium.[5] This is nonobtainable from 2D approach [Figure 3]a and [Figure 3]b.
Figure 3: (a) Global and segmental approach, transesophageal echocardiography localization of pathology which leaflet and which scallop. (b) Cropping of mitral valve in three-dimensional transthoracic echocardiography PLAX view LV side

Click here to view


RT 3D is performed from the left parasternal window in either long or short axis. The image is rotated to view the left atrial aspect of the MV.[4],[6] Image is optimized by probe manipulation to bring leaflets, coaptation line, and annulus to view them entirely. For MV acquisition, FV long-axis view is preferred. This approach is simple and reproducible. When parasternal window is poor, apical windows can be used.

3D TEE is step up in image resolution offered by 3D TTE. Because the closest structure to TEE probe is left atrium, surgical view (en face) of MV is easily possible and rapid. All scallops of both the leaflets of MV can be seen simply without manipulation of the probe and various angulations. Significant advantage of the technique is in obtaining good images, irrespective of heart rhythm. Very little extra time is required to obtain 3D view and can be incorporated in the routine TEE examination [Figure 4]a and [Figure 4]b. A systematic approach to performing a 3D TEE MV examination is recommended. First, 2D TEE examination is done in various angles in midesophageal and transgastric position. Subsequently, 3D TEE data are obtained as RT and gated acquisition up to 120 midesophageal views with or without color to determine the whole valvular structures.[7],[8] Once volumetric data are obtained, one can rotate, angulate, and crop images to assure immediate en face view of MV similar to that seen by surgeons.[9],[10] MV consists of annulus, valvular leaflets, and subvalvular apparatus, which is composed of variable chordae tendineae arrangements with dual papillary muscles [Figure 5].
Figure 4: (a) Segmental approach transesophageal echocardiography midesophageal view. (b) Mitral valve three-dimensional transesophageal echocardiography surgical perspective “en face” view from left atrium side

Click here to view
Figure 5: Mitral valve annulus leaflets and subvalvular apparatus

Click here to view



  Mitral Valve Annulus Top


The MV annulus is an incomplete tissue ring of elliptical or saddle shape.[8] Annulus supports the MV leaflets. Longest diameter runs from commissure to commissure, and shortest diameter is between the midanterior and midposterior segment of the annulus. Usually, 3D offline processing is required for MV annulus analysis. MV modular reconstruction is done to measure annular diameters, area, circumference, and aortic MV angles [Figure 6]a and [Figure 6]b.
Figure 6: Mitral valve annulus (a) anatomical view of mitral valve annulus D-shaped longest diameter is anterolateral-posteromedial and shortest diameter is anteroposterior (b) MVQ (mitral valve quantification) plugin QLAB software offers semi-automated measurement for mitral annulus, valve commissures, leaflet coaptation

Click here to view



  Mitral Valve Leaflets Top


Normal MV has two leaflets described as anterior and posterior leaflets. Anterior leaflet attaches to one-third of the annulus and has wider surface with short base. Narrower posterior leaflet covers two-third of annulus circumference. Slits in posterior leaflet create three scallops from lateral to medial P1P2P3 while corresponding area of anterior mitral leaflet is not anatomically divided and termed as A1A2A3.[11] Middle cusp of posterior leafl et (P2) is further divided into anterolateral PM1 and PM2. Anterior and posterior leaflet are separated by two commissures, anterolateral and posteromedial. Commissures do not extend completely to the annulus, and thus leaflet tissues form a continuous ring around the annulus.


  Subvalvular Apparatus Top


Chordae attached to papillary muscles support the MV leaflets. Chordae bifurcate several times and attach to the ventricular surface of leaflets. Chordae attachment and tips of papillary muscles can be evaluated by 3D FV pyramidal set. The subvalvular apparatus is best studied by a transgastric view with both MV and left ventricle included.


  Mitral Stenosis Top


Mitral stenosis (MS) is usually caused by rheumatic heart disease and is the most common valvular heart disease in developing countries. A fusion of commissures is a major cause of the stenosis. Other causes of MS are degenerative mitral annulus and congenital parachute MV. Commissural involvement is a hallmark of rheumatic process. Diagnosis of MV stenosis commonly involves the use of 2D TTE to assess the severity of MS.[12] This includes MV leaflet mobility, thickening, calcification, and subvalvular thickening. Apart from these, left atrial thrombus, LA enlargement, and commissural fusion are also identified.[13],[14] Normal MV area is 4–6 cm2. Patients with MS typically have a valve area of <2.0 cm2 and severe stenosis when valve area is <1.0 cm2. Various echocardiographic techniques are used to measure MV area, including pressure half time (PHT) and pressure gradient. Planimetry involves direct measurement of MV orifice [Figure 7]. PHT and pressure gradients are affected by the presence of other valvular involvement and hemodynamic parameters. In contrast, planimetry is not affected by hemodynamic variability.[15],[16],[17],[18],[19] However, it is difficult and requires technically challenging imaging views of MV orifice. Proximal isovelocity surface area (PISA) method and continuity equation also involve various variables and most of the time it is technically difficult.[20] Planimetry has become most reliable and trusted for calculating MV area. This has been considered the gold standard for MV area calculation. The stenotic MV is often funnel shaped, and stenotic orifice may be situated obliquely within the ventricle. 2D planimetry is limited by obtaining the correct plane for the cross-section.
Figure 7: Quantification of mitral valve stenosis two-dimensional-Doppler mitral valve annulus two-dimensional planimetry mitral valve annulus pressure half time mitral valve annulus CE or mitral valve annulus proximal isovelocity surface area PG mean three-dimensional echo mitral valve annulus real-time 3DE

Click here to view


Three-dimensional imaging overcomes the difficulties and allows RT display.[17] RT 3D imaging is more accurate and reliable than 2D echo planimetry for assessing the MV area, severity of commissural fusion, and extent of subvalvular disease.[8],[18],[19] RT 3D planimetry is performed en face at the ideal cross-section of MV during its greatest diastolic opening. The ideal cross-section was defined as the most perpendicular view on the plane with the smallest MV orifice.

The use of 3D is an accurate method for assessing the MV area and is faster and more reproducible even in less experienced hand.[20] Live 3D imaging helps overcome the stitching artifacts, especially in atrial fibrillation. RT 3D TEE, the narrowest valve orifice, is always imaged both from above and below the MV. Measurement is properly made by cropping the volume data set level of plane corresponding to the smallest orifice [Figure 8]. Narrowest valve area displays improved accuracy and it reduces interobserver variability. RT 3D TEE yields striking images in patients with MS. Apart from the valve area, RT 3D TEE shape, location, and anatomical abnormalities of leaflets, calcification, etc., are well visualized [Figure 9]. There is a tendency of overestimation of the MVA by 2D planimetry, and it is suggested that 3D TEE should be considered for accurate measurement, especially in patients with a large atrium and large angle between lines of true MV tip and echo beam to the tip.
Figure 8: Mitral valve area multiplanar reconstruction: smallest mitral valve area can be properly planimetered by moving cropping three orthogonal planes. Red, green, and blue

Click here to view
Figure 9: Segmental approach transesophageal echocardiography midesophageal view anterolateral commissure is completely fused and posteromedial commissure is open. Severe calcific mitral stenosis valve area 0.9 cm2 leaflets and commissural calcification

Click here to view


Valve area measurement using flow convergence (PISA) with single beat RT 3D color Doppler echocardiography reported feasible in the clinical setting and more accurate than the conventional 2D PISA method. Detailed analysis of MV commissures is of particular interest in patient being considered for MV commissurotomy.[21],[22] Commissures are best obtained from the midesophageal position by RT live 3D echo. This provides the best temporal and spatial resolution when narrow volume is used for analysis. TEE shows the severity of fusion as well as a symmetrical or asymmetrical fusion of the commissures [Figure 9].


  Mitral Regurgitation Top


RT 3D echo turned out to be crucial in providing insights into the MV complex, enhancing operative and interventional approaches and patient care. Mitral regurgitation (MR) is classified as either organic or functional in etiology. Organic MR is usually caused by degenerative abnormalities such as MV prolapse or flail MV leaflets [Figure 10]. However, MR is also caused by rheumatic pathology mostly in association with MS. MR can be a result of the infective endocarditis usually secondary to primary organic disease of the MV. Surgical correction for tailored reconstructive operations and emerging percutaneous techniques necessitates a deeper understanding of pathophysiology and more accurate quantification of the severity of MR.[4],[23]
Figure 10: Mitral valve prolapse real-time three-dimensional transesophageal echocardiography: zoom enface view mitral valve prolapse P2P3 segment with chordae rupture real-time three-dimensional transesophageal echocardiography: zoom enface view

Click here to view


The surgical en face view provides an exceptionally realistic portrayal of both leaflets. 3D echo has contributed considerably to our understanding of the role of spatial interaction between the components, promoting efficient valve closure. The mitral annulus has a nonplanar, saddle-shaped oval configuration which can be characterized by several parameters by RT 3D echo, such as anteroposterior and intercommissural diameter, area, height, and ellipticity. There are two high points anteriorly and posteriorly while lower points medially and laterally. Anteriorly, it is fibrous mitral-aortic continuity while posterior portion is muscular. Normal saddle-shaped annulus shows cyclic variation in size and shape. During cardiac cycle, RT 3D echo has been demonstrated to add relevant information about differences in annular shape and function in various cardiac diseases. Functional and ischemic MR is associated with dilatation, flattening, and reduction of contractility. In myxomatous disease, the annulus is enlarged, but remains dynamic. In long-standing MR, there is blunting of the area changes of annulus and this may be the reason of the development of MR [Figure 6].[24]

Information or pathologic anatomy of leaflets provided by echocardiography has become indispensable for MV repair procedure. Accurate segmental analysis by 2D echo has major limitations and needs expertise and mental 3D reconstruction of the image. RT 3D echo can depict the valve both from the ventricular and atrial aspects. The entire surface of both leaflets is clearly visible from the atrial aspects. While insertion of chordae is clearly visualized from the left ventricular perspective, the possibility of free sliding and rotation of cutting planes in 3D volume may be advantageous in determining the exact location of prolapse or flail, perforation, and cleft [Figure 10]. The use of RT 3D TEE has been extensively used for high-quality images of MV.[25]

3D echo also provides color Doppler flow data; hence, the origin of regurgitant jet and site of responsible valve abnormality can be easily determined. RT 3D TEE has been shown useful in measuring the gap width of MV prolapse and flail. It also provides a better overall perspective of MV than 2D TEE, including the shape of prolapse and the exact size and location of the prolapsing segment with the use of surgical en face view [Figure 10].

3D RT TEE or TTE provides 3D images of regurgitant jet and flow convergence.[26],[27] Location of the regurgitant orifice [Figure 11] and size of flow convergence (PISA) can determine the location of regurgitant orifice and severity of MR. This information is critical for selecting the appropriate corrective procedures. Color Doppler 3D echo has demonstrated that PISA in many circumstances is not hemispherical. It is irregular or asymmetrical in patients with functional or ischemic MR[28],[29],[30],[31] [Figure 12].
Figure 11: Vena contracta (different shapes) degenerative mitral valve disease functional mitral valve disease

Click here to view
Figure 12: Proximal isovelocity sur face area in a real-time three-dimensional color Doppler transesophageal echocardiography dataset of a patient with moderate-to-severe functional mitral regurgitation. The figure top left shows an uncropped view from the LA perspective to the broad jet along the commissure line. Top right panel shows a view from the LV perspective to the asymmetric proximal isovelocity surface area at a Nyquist velocity of 30.8 cm/s. The proximal isovelocity surface area appears narrow in a long-axis LVOT three-dimensional view (bottom left) and broad in a two-chamber view (bottom right). LA: Left atrium, LVOT: Left ventricular outflow tract

Click here to view


Vena contracta area (VCA) as determined by color Doppler 3D echocardiography has been repeatedly found useful for qualitatively defining the MR severity [Figure 13]. These studies have shown a curved vena contracta, especially in functional MR. Idea of 3D VCA seems attractive because it is independent of geometric assumptions. VCA may be difficult to obtain in eccentric jets. The cutoff values of VCA for severe MR have not been firmly established. Both PISA method and VCA are used for the severity of MR for increasing the accuracy.[31],[32],[33]
Figure 13: Vena contracta real-time three-dimensional color Doppler transesophageal echocardiography dataset in severe functional mitral regurgitation. Three-dimensional view of mitral valve and mitral regurgitation jet from an left atrium perspective (bottom right) and three reconstructed planes in orthogonal orientation to the mitral regurgitation jet: long-axis left ventricular outflow tract view, two-chamber view, short-axis view showing the asymmetric vena contracta area (1.03 cm2 by direct planimetry, short-axis diameter (D1) = 0.54 cm, long-axis diameter (D2) = 2.24 cm) represented in real-time three-dimensional color Doppler transesophageal echocardiography en face views to the vena contracta area

Click here to view


An anatomical module can be displayed using MV quantification software that helps understand the pathology better. MV annulus, geometry (e.g., excursion, shape, and curvature), leaflet surface tethering distance, tenting volume, and relation between MV and papillary muscles are nicely demonstrated.[8]

The following parameters are useful for the quantification of MR [Figure 11], [Figure 12], [Figure 13], [Figure 14].

  1. Quantification of MV annulus (diameter, area, and dynamics)
  2. Measurement of leaflets (length, area, volume, and height of prolapse)
  3. Calculation of tenting (distance and volume)
  4. Planimetry VCA
  5. Direct measurement of anatomic regurgitant orifice area (ROA)
  6. Effective ROA (EROA) calculation using PISA avoids geometric assumption
  7. Accurate quantification of stroke volume.


These various parameters obtained through RT 3D echo (TTE/TEE) can improve the planning of complex surgical or interventional procedures.[34]{Figure 11}{Figure 12}{Figure 13}
Figure 14: Important parameters derived by real-time 3DE before mitral valve repair anterior-posterior diameter (DAP) anterolateral-posteromedial diameter (DAIPm) three-dimensional curvilinear length of posterior and anterior leaflet exposed area of leaflets minimal area of leaflets within the saddle-shaped annulus (A3Dmin) volume of leaflet prolapse (VProl) maximal prolapse height (HProl) length of anterolateral and posteromedial chordae tendineae

Click here to view



  Mitral valve prolapse Top


MV prolapse (MVP) is defined as abnormal bulging of MV leaflet segments in the left atrium past the plane of mitral annulus during systole. Free leaflet edge is seen toward the left ventricle, while in severe cases, free edge may lose chordal support and evert into the left atrium during systole. When this occurs, the MV leaflet is said to be flail. On the basis of the 2D TTE, the prevalence of MVP is calculated at 2.4% by Framingham data.[35],[36] MVP is difficult to fully characterize by 2D echo. RT 3D echo notably 3D TEE provides an unprecedented view of MVP from the left atrial perspective [Figure 15].
Figure 15: Prolapse of P2 and P3 segment of mitral valve leaflet three-dimensional echo appearance of prolapse and flail mitral segments in three-dimensional enface view from the LA perspective

Click here to view


MVP is characterized by excessive leaflet (≥2 mm abnormal systolic movement) beyond the saddle-shaped annulus level. Degenerative MR etiology encompasses a wide pathological spectrum from a fibroelastic deficiency (FED) to extensive myxomatous disease and the Barlow's disease (BD). BD is characterized by diffuse excessive tissue with large valves comprising multiple degenerative segments associated with thick and elongated chordae.[37] Annular dilatation is usually associated with different degrees of calcification. In contrast, FED is usually, but not exclusively involves middle scallop of the posterior MV leaflet. This is usefully associated with thin and elongated ruptured chordae.[38]

3D echocardiographic imaging contributed to our knowledge of degenerative MR. MVP may be either primary or secondary. Primary MVP refers to conditions in which primary abnormality is of mitral leaflets, whereas secondary MVP refers to conditions when leaflet prolapse is secondary to abnormality in subvalvular apparatus.[39]

Most clinically useful 3D echocardiographic view for the diagnosis of MVP is the en face view of MV from the LA perspective. The left atrial side is in the near field of 3D TEE and far field of 3D TTE. Thus 3D TEE provides superior images of MVP compared to 3DTTE. In a study of 204 patients, 3D TEE had an accuracy of 92% compared to 78% accuracy rate of 2D TEE.[4] In 3D en face view, number of prolapsing segments, their location and their extent, and presence or absence of the flail segment can be easily visualized by 3D TEE [Figure 14]. It is important to evaluate the en face view of MV not only in surgical view but also from other perspectives after rotating the en face view along the Z-axis[40] (the axis perpendicular to the plane of imaging) [Figure 16].{Figure 14}
Figure 16: Mitral valve prolapse segments angled enface views

Click here to view


Advanced software packages for advanced MVP calculations are available and their clinical utility is proven. Quantifying the data from these softwares provides anteroposterior leaflet area as well as billowing volume and height of prolapsing segment. These advanced techniques allow discrimination between BD and FED[37],[38] [Figure 17].[37]
Figure 17: Degenerative mitral valve prolapse fibroelastic deficiency billowing disease example of three-dimensional transesophageal echocardiography and corresponding reconstruction of mitral annulus and leaflets in a patient with fibroelastic deficiency (left) and in two patients with Barlow disease (right). In the first case, reconstruction clearly shows (red surface) the P2 prolapsed segment. The two Barlow cases with the same method are characterized by multiple scallop involvement of both leaflets identified by the red surfaces

Click here to view


MV annulus is still dynamic, but behaves considerably different from normal individual with loss of early systolic area contraction and saddle-shape deepening. Subsequent area enlargement may contribute to mitral incompetence. Dilatation of the annulus is more in anteroposterior and intercommissural directions than height in both BD and FED, but more in BD. This results in flatter annulus.[37]

MVP-related MR has more dilated and flattened annulus, redundant leaflet surfaces, greater leaflet billowing volume, height and longer length from papillary muscles to the coaptation, and more frequent chordal rupture as compared to nonprolapsing MR. These findings suggest that the loss of saddle shape may predispose to chordal elongation and rupture as a result of chordal tension.

Prognosis and the best timing of surgical intervention in degenerative MV disease strongly depend on accurate quantification of MR severity. Recently 3D VCA, 3D PISA techniques, ability to measure 3D surface of the proximal flow convergence region and the largest radius of PISA using 3D navigation possibly increase the accuracy of EROA calculation.

Accurate preoperative RT 3D TTE or RT 3D TEE eventually with postprocessing software may facilitate surgical planning, allowing a tailored approach to each case.[41] RT 3D TEE was found to be helpful in several catheter-based procedures, including MitraClip repair of MR.


  Three-Dimensional Echo for Mitral Valve Interventions Top


Percutaneous balloon mitral valvuloplasty

Percutaneous balloon mitral valvuloplasty (PBMV) is a procedure of choice when the MV anatomy is favorable. Variation in MV area obtained using PHT and those derived from catheterization has been observed. Planimetry of the MV area is taken as more accurate and possibly RT 3D TEE-derived MV area is the new gold standard.[4],[13]

Following the introduction of INOUE balloon catheter in 1984, PBMV has become a safe and effective treatment of MS. It is a preferred treatment option for selected symptomatic MS patients. Proper patient selection is of major importance when predicting immediate and long-term effects of PBMV. Wilkins et al. proposed splitability score, which is most validated and commonly used echocardiographic criteria for PBMV.[42],[43] This score is based on transthoracic echo findings, taking into account the severity and extent of leaflet calcification, leaflet thickening, mobility, and involvement of subvalvular apparatus. Each of these parameters was graded on a scale of 0–4, and the maximum score is 16. The cutoff point was less and equal to eight for the best short- and long-term results [Table 2].[42] However, Palcios et al. demonstrated the importance of MR, especially when it is 2 or 2+ and is associated with worse outcome. Importance of the degree of commissural splitting has also been emphasized by the same author.[44],[XS45] Anwar et al. introduced a score based on RT-3D TTE or the assessment of patient with MS before PBMV. This score includes the evaluation of the mitral leaflets and subvalvular apparatus. This new transthoracic 3D echo-based score is feasible and highly reproducible and is better for detecting calcification and predicting commissural splitting [Table 3].[46] All scoring systems are limited by their reproducibility as the scores are semiquantitative and lesions may be underestimated.
Table 2: Mitral valve anatomy scoring using the Wilkin's score

Click here to view
Table 3: Real-Time Transthoracic 3-Dimensional Echocardiographic Score for the Evaluation of Mitral Stenosis Before Percutaneous Mitral Balloon Valvuloplasty

Click here to view


RT 3D TTE has allowed multiplanar reformatting with more precise measurement of MV area before the procedure. 3D TEE allows the interrogation of commissures more directly and helps define the asymmetric fusions or calcification of commissures. Asymmetric MV orifice may increase the risk of MR with PBMV. Commissures are best assessed from a midesophageal position of RT 3D TEE (narrow angle). While inspecting the commissures, the fusion and severity of calcification are better observed. RT 3D TEE shows clearly whether the fusion is more pronounced in single commissure (asymmetric fusion) or both commissures are equally affected (symmetric fusion). 3D TEE before PBMV is also useful to screen for LA and LAA thrombus or dense spontaneous echo contrast.

During the procedure of PBMV, RT 3D TEE can be used under conscious sedation and helps guide transseptal puncture. It is also utilized for optimization of balloon position across mitral leaflets and avoids entrapment of subvalvular apparatus. RT 3D TEE is useful in identifying and preventing complications during PBMV. The postprocedure aim of RT 3D TEE is to identify commissural splitting (symmetrical or asymmetrical), PG across the mitral leaflets, MVA by planimetry and severity of MR, and also if any increase of pericardial effusion. RT 3D TEE with multiplanar reformatting immediately after PBMV provides superior estimation of MV area. Postprocedural leaflet tear is better identified by RT 3D TEE. The sizing of INOUE balloon is important to minimize leaflet tear; traditionally, height of the patient and body surface area is utilized.[47] The choice of the balloon size may be optimized by 3D measurement of intercommissural diameter in middiastole [Figure 18].
Figure 18: Percutaneous balloon mitral valvuloplasty (procedure guidance) (a-c) severe mitral stenosis (prepercutaneous balloon mitral valvuloplasty) (d). Atrial septal puncture site (e). Inoue balloon dilation (f). Postpercutaneous balloon mitral valvuloplasty mitral valve opening

Click here to view



  Mitraclip (Edge-To-Edge Repair of Mitral Valve) Top


MR is a major contributor to congestive cardiac failure. Patients with advance age and comorbidities may not be a candidate of surgical MV repair. The MitraClip system was intended to mimic Alfieri surgical stitch approach to repair MV and reduce MR. The heart team approach between cardiac surgeon, interventionist, and skilled echocardiographer is a key for the successful MitraClip procedure [Figure 19]. Data of Everest Trials I, II demonstrated that the MitraClip procedure is feasible and safe. ACCESS-EU has demonstrated 81.8% survival at 1 year and 78.9% freedom from severe MR. Meta-analysis of 16 studies has concluded low adverse event profile and only 14.7% of patients showing severe MR.[48],[49]
Figure 19: MitraClip procedure guidance (a). Eccentric mitral regurgitation jet by plane two-dimensional view (b). Flail mitral leaflet P2 segment (three-dimensional transesophageal echocardiography en face view) (c). Three-dimensional transesophageal echocardiography mitral regurgitation jet (d). Coaptation line (e). Septal puncture site (f). LA height from the puncture site (g). Splitting of mitral regurgitation jet by MitraClip (h). MitraClip in position after gripping both mitral valve leaflets resulting in double barrel mitral valve opening (i). Postprocedural Grade I mitral regurgitation

Click here to view


COAPT investigators have recently presented and published the data of the trial between the transcatheter MV approximation using MitraClip with maximally tolerated guideline-directed medical therapy (GDMT).[50] MitraClip insertion was superior to GDMT alone in reducing the heart failure hospitalization and mortality in symptomatic heart failure patients with Grade III-IV in functional MR.

The MITRA-FR trial showed that in patients with severe secondary MR, percutaneous mitral valve repair plus medical treatment did not result in a lower rate of the composite outcome of death from any cause or unplanned hospitalization for heart failure at 12 months than medical treatment alone.[51] These results are in contraindication to COAPT trial. However, in this study, it is pointed out that investigators included patients with very low ejection fraction (EF) and also the number of patients with only moderate (2+) MR.

The MitraClip procedure requires identifying the morphology and pathology of MR.

Eligibility for MitraClip procedures are as follows [Figure 20]:

  • Coaptation length >2 mm
  • Coaptation depth <11 mm
  • Flail gap <10 mm
  • Flail width <15 mm.


3D and 2D TEE are used for preprocedural assessment in steps to define MV area, ruling out ASD and patent foramen ovale, to define site of prolapse or flail and severity of MR. Site of MR is also confirmed. 3D TEE is often helpful, especially in high esophageal view, midesophageal, and lower esophageal view in various orientations to determine the site and size of MR. Color compare especially in 0° degree commissural view and also long-axis view is important. RT 3D TEE in enface surgical view for MV clearly defines the site of pathology and origin of MR jet.
Figure 20: Functional mitral regurgitation degenerative mitral regurgitation (flail) anatomic eligibility criteria for MitraClip (EVEREST Trial) (a) in functional mitral regurgitation, the primary mechanisms are mitral annular dilation and leaflet restriction secondary to the LV remodeling. Apical tethering with malcoaptation of the mitral valve leaflets. The coaptation length at least 2 mm and coaptation depth <11 mm (b) in degenerative mitral regurgitation with mitral valve prolapse and/or flail, flail depth <11 mm, and a flail width <15 mm are features associated with MitraClip procedural success

Click here to view


MitraClip procedure has been successful in reducing MR in two groups of patients, those with excessive leaflet motion (myxomatous degeneration with prolapse or flail) or those with functional MR. MitraClip is not recommended for the rheumatic MR with leaflet movement restriction. RT 3D imaging has improved visualization of MV scallops. Calcification of leaflets at the site regurgitation is not desirable. VC, PISA, and systolic reversal of flow in one or more pulmonary veins are important to recognize the severity of MR.[48],[52],[53]

3D TEE provides en face views of MV, thus facilitating the assessment of MV morphology and pathology. Delivery catheters, wire, device, and target mitral leaflet scallops are recognized in single view, thus optimizing the septal puncture, steering of delivery system in 3D space toward the MV, and good MitraClip positioning perpendicular to the line of coaptation in the middle segment of the MV. Combination of 2D, RT 3D TEE, and fluoroscopy provides integrated approach and reduces procedure time.

The MitraClip procedure has four important steps.[48]

  1. Transseptal puncture
  2. Advancement of steerable guide catheter into LA
  3. Advancement of MitraClip delivery into the left atrium and positioning of MitraClip below the MV leaflets
  4. Grasping of leaflets and assessment of results and MitraClip release.


As the MitraClip delivery system exits the sheath, it is required to monitor the movement of clip and guide it above the MV through manipulation under the guidance of RT 3D TEE and fluoroscopy avoiding the injury to the LA wall and also avoiding entry into the LAA. Medial, lateral and anterior, and posterior adjustment are done directing under 3D en face view in an orthogonal midesophageal long-axis (LVOT) view. To achieve good clip alignment, both arms of opened clip can be visualized in full length in long-axis view. The tip of the clip should be directed toward largest PISA. A single 3D en face view allows to determine when clip is adequately positioned above middle segment of the MV and clip orientation is perpendicular to MV coaptation line. Once the MitraClip is in satisfactory position above the valve, it is advanced to the LV under fluoroscopy and RT 3D TEE guidance. Grasping of leaflets as they are captured between clip arms and gripper is monitored using a 2D LVOT view. Multiple planes are useful for the assessment of proper leaflet insertion into MitraClip. Formation of the double-barreled orifice is confirmed by 3D en face view, and it is ensured that both orifices are approximately of the same size. After implantation of MitraClip, residual regurgitation and pressure gradient are assessed.[53]

The MitraClip procedure is rapidly evolving, and it is an important option for therapy of severe MR.


  Paravalvular Leak Closure Top


RT 3D TEE imaging is critically important in paravalvular leak (PVL) closure and it helps interventionist:[42],[54],[55]

  1. To locate the optimal region of transseptal puncture
  2. To guide the crossing of defect that leads to PVL
  3. To monitor the decrease of PVL during balloon inflation
  4. To monitor the complication, especially pericardial effusion, postprocedural atrial septal defect, and prosthetic valve leaflet entrapment.


Although 2D TEE with color Doppler imaging is a mainstay tool to identify PVL and guiding the closure, the use of RT 3D TEE with color Doppler is useful [Figure 21].
Figure 21: Paravalvular leak (closure) (a). Para valve leak 8 O'clock position (b). Para valve leak with color flow 2 O'clock position (c). Para valve leak closure one device (d). Para valve leak closure two devices clips provided Courtesy Dr. S. Radha Krishnan FEHI DelhiFigure 21: Paravalvular leak (closure) (a). Para valve leak 8 O'clock position (b). Para valve leak with color flow 2 O'clock position (c). Para valve leak closure one device (d). Para valve leak closure two devices clips provided Courtesy Dr. S. Radha Krishnan FEHI Delhi

Click here to view



  Real-Time Three-Dimensional Transesophageal Echocardiography for Surgical Mitral Valve Repair Top


3D echo has a pivotal role in choosing the optimal surgical treatment for MR. The global characterization of the valve morphology in terms of annular enlargement, planimetry, dynamicity, coaptation geometry, and leaflet redundancy defines useful parameters for guiding surgery.[23] The most useful parameters offered by 3D quantification software are the 3D area and axis of annulus, curvilinear length of A2 and P2 scallops, and 3D leaflet surface area and distances between the commissures and papillary muscles. Different patterns of annular distortion revealed by 3D echo have provided the use for different designs and sizes of annuplasty ring.[56] Information or tissue redundancy of the prolapsing leaflet can guide surgeons in deciding the extent of MV resection. The curvilinear leaflet length, exposed leaflet surface area, and volume of prolapse measured scallop by scallop are key parameters to use during MV repair.[57],[58]

3D TEE had a sensitivity of 100% for all segments except posterior commissure 95%. The sensitivity of 2D TEE was generally lower. The accuracy of 3D TEE for detecting anterior and bileaflet prolapse was 100% and 98%, respectively, and was higher than 2D TEE. Overall, accuracy in detecting prolapsed segment was 50% with 2D TEE and 86% with 3D TEE.[21]

3D TEE measurements of prolapsed segment height did not differ significantly as compared with intraoperative finding.

Impact of three-dimensional transesophageal echocardiography assessment of mitral valve anatomy for surgical repair

Anatomical predictors of lower likelihood of the success of surgical repair are the involvement of anterior leaflet, bileaflet prolapse, severe annular calcification, and increased annular dimension. Leaflet height is an independent predictor of successful MV repair. 3D TEE is more accurate for evaluating these parameters. FED and BD are well differentiated by 3D TEE and are crucial for surgical strategies, operative risk, and outcome.

3D TEE has been shown to facilitate visualization of the entire structure of new artificial valve (PHV). In addition, color Doppler 3D TEE can detect the location of any paravalvular leak. Exact location and circular extent of paravalvular leak can be recognized which allows immediate surgical correction. MV repair is an effective strategy that has a significant advantage over valve replacement surgery. The primary goal of MV repair is that the large area of leaflet coaptation can be created.[59] The degree of coaptation is an important parameter when assessing the valve geometry and function before and postoperatively. 2D TEE is fundamentally limited to 1D measurements. Spatial orientation may be difficult to determine from 2D TEE. RT 3D TEE method is novel technology, and it provides excellent images and accurate estimation of the mitral coaptation zone.[60]


  Conclusion Top


Echocardiography is the most important technique for the diagnosis of MV disease. TEE is also used when transthoracic echo is not sufficient for the diagnosis or severity of the disease. Since the advent of RT 3D echo with matrix transducers, 3D transthoracic as well as 3D transesophageal echo has added value for the assessment of MV complex and exploration of the etiology and mechanism of MV abnormality. RT 3D TEE has opened a new vista for quantification of an MV area as well as quantification of MR. RT 3D echo is also utilized and has become an integral part of MV interventions and planning the MV surgery. 3D echocardiography is the new gold standard for MV disease.

Acknowledgments

The authors would like to thank Suruchi Malhotra for typing and preparation of the manuscript, Tauheed Alam for the collection of references and data, Sukhveen Kaur Suri for the collection of representative photographs, and Sudhir Shekhawat for the collection of references and manuscript preparation.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Vegas A. Three-dimensional transesophageal echocardiography: Principles and clinical applications. Ann Card Anaesth 2016;19:S35-43.  Back to cited text no. 1
[PUBMED]  [Full text]  
2.
Sugeng L, Shernan SK, Salgo IS, Weinert L, Shook D, Raman J, et al. Live 3-dimensional transesophageal echocardiography initial experience using the fully-sampled matrix array probe. J Am Coll Cardiol 2008;52:446-9.  Back to cited text no. 2
    
3.
Lang RM, Badano LP, Tsang W, Adams DH, Agricola E, Buck T, et al. EAE/ASE recommendations for image acquisition and display using three-dimensional echocardiography. J Am Soc Echocardiogr 2012;25:3-46.  Back to cited text no. 3
    
4.
Shiota T. Role of modern 3D echocardiography in valvular heart disease. Korean J Intern Med 2014;29:685-702.  Back to cited text no. 4
    
5.
Delabays A, Jeanrenaud X, Chassot PG, Von Segesser LK, Kappenberger L. Localization and quantification of mitral valve prolapse using three-dimensional echocardiography. Eur J Echocardiogr 2004;5:422-9.  Back to cited text no. 5
    
6.
Sugeng L, Coon P, Weinert L, Jolly N, Lammertin G, Bednarz JE, et al. Use of real-time 3-dimensional transthoracic echocardiography in the evaluation of mitral valve disease. J Am Soc Echocardiogr 2006;19:413-21.  Back to cited text no. 6
    
7.
Zakkar M, Patni R, Punjabi PP. Mitral valve regurgitation and 3D echocardiography. Future Cardiol 2010;6:231-42.  Back to cited text no. 7
    
8.
Drasutiene A, Aidietiene S, Zakarkaite D. The role of real time three dimensional transesophageal echocardiography in acquired mitral valve disease. Semin Cardiovasc Med 2015;21:16-26.  Back to cited text no. 8
    
9.
Bushra SR, Justin MS, Petros Nihoyannopoulos. 3D Echocardiography in mitral valve heart disease – Is it the New Gold Standard. European Cardiology 2010;6:61-6.  Back to cited text no. 9
    
10.
Flachskampf FA, Badano L, Daniel WG, Feneck RO, Fox KF, Fraser AG, et al. Recommendations for transoesophageal echocardiography: Update 2010. Eur J Echocardiogr 2010;11:557-76.  Back to cited text no. 10
    
11.
Carpentier A. Cardiac valve surgery: The 'French correction'. J Thorac Cardiovasc Surg 1983;86:323-37.  Back to cited text no. 11
    
12.
Wilkins GT, Weyman AE, Abascal VM, Block PC, Palacios IF. Percutaneous balloon dilatation of the mitral valve: An analysis of echocardiographic variables related to outcome and the mechanism of dilatation. Br Heart J 1988;60:299-308.  Back to cited text no. 12
    
13.
Soliman OI, Anwar AM, Metawei AK, McGhie JS, Geleijnse ML, Ten Cate FJ, et al. New scores for the assessment of mitral stenosis using real-time three-dimensional echocardiography. Curr Cardiovasc Imaging Rep 2011;4:370-7.  Back to cited text no. 13
    
14.
Salcedo EE, Quaife RA, Seres T, Carroll JD. A framework for systematic characterization of the mitral valve by real-time threedimensional transesophageal echocardiography. J Am Soc Echocardiogr 2009;22:1087-99.  Back to cited text no. 14
    
15.
Baumgartner H, Hung J, Bermejo J, Chambers JB, Evangelista A, Griffin BP, et al. Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. J Am Soc Echocardiogr 2009;22:1-23.  Back to cited text no. 15
    
16.
Zamorano J, Perez de Isla L, Sugeng L, Cordeiro P, Rodrigo JL, Almeria C, et al. Non-invasive assessment of mitral valve area during percutaneous balloon mitral valvuloplasty: Role of real-time 3D echocardiography. Eur Heart J 2004;25:2086-91.  Back to cited text no. 16
    
17.
Messika-Zeitoun D, Iung B, Brochet E, Dominique Himbert. Evaluation of mitral stenosis in 2008. Arch Cardiovasc Dis 2008;101:653-63.  Back to cited text no. 17
    
18.
Faletra FF, de Castro S, Pandian NG, Kronzon I, Nesser HJ, Yen Ho S. Atlas of Real Time 3D Transesophageal Echocardiography. Berlin: Springer-Verlag; 2010.  Back to cited text no. 18
    
19.
Sugeng L, Shernan SK, Weinert L, Shook D, Raman J, Jeevanandam V, et al. Real-time three-dimensional transesophageal echocardiography in valve disease: Comparison with surgical findings and evaluation of prosthetic valves. J Am Soc Echocardiogr 2008;21:1347-54.  Back to cited text no. 19
    
20.
de Agustin JA, Mejia H, Viliani D, Marcos-Alberca P, Gomez de Diego JJ, Nuñez-Gil IJ, et al. Proximal flow convergence method by three-dimensional color Doppler echocardiography for mitral valve area assessment in rheumatic mitral stenosis. J Am Soc Echocardiogr 2014;27:838-45.  Back to cited text no. 20
    
21.
Biaggi P, Jedrzkiewicz S, Gruner C, Meineri M, Karski J, Vegas A, et al. Quantification of mitral valve anatomy by three-dimensional transesophageal echocardiography in mitral valve prolapse predicts surgical anatomy and the complexity of mitral valve repair. J Am Soc Echocardiogr 2012;25:758-65.  Back to cited text no. 21
    
22.
Ben Zekry S, Nagueh SF, Little SH, Quinones MA, McCulloch ML, Karanbir S, et al. Comparative accuracy of two- and three-dimensional transthoracic and transesophageal echocardiography in identifying mitral valve pathology in patients undergoing mitral valve repair: Initial observations. J Am Soc Echocardiogr 2011;24:1079-85.  Back to cited text no. 22
    
23.
Saric M, Perk G, Purgess JR, Kronzon I. Imaging atrial septal defects by real-time three-dimensional transesophageal echocardiography: Step-by-step approach. J Am Soc Echocardiogr 2010;23:1128-35.  Back to cited text no. 23
    
24.
Evangelista A, Aguilar R, Cuellar H, Thomas M, Laynez A, Rodríguez-Palomares J, et al. Usefulness of real-time three-dimensional transoesophageal echocardiography in the assessment of chronic aortic dissection. Eur J Echocardiogr 2011;12:272-7.  Back to cited text no. 24
    
25.
Wei J, Hsiung MC, Tsai SK, Ou CH, Chang CY, Chang YC, et al. The routine use of live three-dimensional transesophageal echocardiography in mitral valve surgery: Clinical experience. Eur J Echocardiogr 2010;11:14-8.  Back to cited text no. 25
    
26.
Siddiqi N, Seto A, Patel PM. Transcatheter closure of a mechanical perivalvular leak using real-time three-dimensional transesophageal echocardiography guidance. Catheter Cardiovasc Interv 2011;78:333-5.  Back to cited text no. 26
    
27.
Izumo M, Shiota M, Kar S, Gurudevan SV, Tolstrup K, Siegel RJ, et al. Comparison of real-time three-dimensional transesophageal echocardiography to two-dimensional transesophageal echocardiography for quantification of mitral valve prolapse in patients with severe mitral regurgitation. Am J Cardiol 2013;111:588-94.  Back to cited text no. 27
    
28.
Li X, Shiota T, Delabays A, Teien D, Zhou X, Sinclair B, et al. Flow convergence flow rates from 3-dimensional reconstruction of color Doppler flow maps for computing transvalvular regurgitant flows without geometric assumptions: An in vitro quantitative flow study. J Am Soc Echocardiogr 1999;12:1035-44.  Back to cited text no. 28
    
29.
Sitges M, Jones M, Shiota T, Qin JX, Tsujino H, Bauer F, et al. Real-time three-dimensional color Doppler evaluation of the flow convergence zone for quantification of mitral regurgitation: Validation experimental animal study and initial clinical experience. J Am Soc Echocardiogr 2003;16:38-45.  Back to cited text no. 29
    
30.
Altiok E, Hamada S, van Hall S, Hanenberg M, Dohmen G, Almalla M, et al. Comparison of direct planimetry of mitral valve regurgitation orifice area by three-dimensional transesophageal echocardiography to effective regurgitant orifice area obtained by proximal flow convergence method and vena contracta area determined by color Doppler echocardiography. Am J Cardiol 2011;107:452-8.  Back to cited text no. 30
    
31.
Matsumura Y, Fukuda S, Tran H, Greenberg NL, Agler DA, Wada N, et al. Geometry of the proximal isovelocity surface area in mitral regurgitation by 3-dimensional color Doppler echocardiography: Difference between functional mitral regurgitation and prolapse regurgitation. Am Heart J 2008;155:231-8.  Back to cited text no. 31
    
32.
Shiota T, Jones M, Yamada I, Heinrich RS, Ishii M, Sinclair B, et al. Effective regurgitant orifice area by the color Doppler flow convergence method for evaluating the severity of chronic aortic regurgitation. An animal study. Circulation 1996;93:594-602.  Back to cited text no. 32
    
33.
Youefy C, Hung J, Chua S et al. Direct measurement of vena contracta area by real time 3Dimensional echovardiography for assessing severity of mitral regurgitation. Am J Carddiol 2009;104:978-983.  Back to cited text no. 33
    
34.
Zeng X, Levine RA, Hua L, Morris EL, Kang Y, Flaherty M, et al. Diagnostic value of vena contracta area in the quantification of mitral regurgitation severity by color Doppler 3D echocardiography. Circ Cardiovasc Imaging 2011;4:506-13.  Back to cited text no. 34
    
35.
Freed LA, Levy D, Levine RA, Larson MG, Evans JC, Fuller DL, et al. Prevalence and clinical outcome of mitral-valve prolapse. N Engl J Med 1999;341:1-7.  Back to cited text no. 35
    
36.
Grewal J, Suri R, Mankad S, Tanaka A, Mahoney DW, Schaff HV, et al. Mitral annular dynamics in myxomatous valve disease: New insights with real-time 3-dimensional echocardiography. Circulation 2010;121:1423-31.  Back to cited text no. 36
    
37.
Maffessanti F, Marsan NA, Tamborini G, Sugeng L, Caiani EG, Gripari P, et al. Quantitative analysis of mitral valve apparatus in mitral valve prolapse before and after annuloplasty: A three-dimensional intraoperative transesophageal study. J Am Soc Echocardiogr 2011;24:405-13.  Back to cited text no. 37
    
38.
Lee AP, Hsiung MC, Salgo IS, Fang F, Xie JM, Zhang YC, et al. Quantitative analysis of mitral valve morphology in mitral valve prolapse with real-time 3-dimensional echocardiography: Importance of annular saddle shape in the pathogenesis of mitral regurgitation. Circulation 2013;127:832-41.  Back to cited text no. 38
    
39.
La Canna G, Arendar I, Maisano F, Monaco F, Collu E, Benussi S, et al. Real-time three-dimensional transesophageal echocardiography for assessment of mitral valve functional anatomy in patients with prolapse-related regurgitation. Am J Cardiol 2011;107:1365-74.  Back to cited text no. 39
    
40.
Chikwe J, Adams DH, Su KN, Anyanwu AC, Lin HM, Goldstone AB, et al. Can three-dimensional echocardiography accurately predict complexity of mitral valve repair? Eur J Cardiothorac Surg 2012;41:518-24.  Back to cited text no. 40
    
41.
Yosefy C, Levine RA, Solis J, Vaturi M, Handschumacher MD, Hung J, et al. Proximal flow convergence region as assessed by real-time 3-dimensional echocardiography: Challenging the hemispheric assumption. J Am Soc Echocardiogr 2007;20:389-96.  Back to cited text no. 41
    
42.
Cavalcante JL, Rodriguez LL, Kapadia S, Tuzcu EM, Stewart WJ. Role of echocardiography in percutaneous mitral valve interventions. JACC Cardiovasc Imaging 2012;5:733-46.  Back to cited text no. 42
    
43.
Palacios IF, Sanchez PL, Harrell LC, Weyman AE, Block PC. Which patients benefit from percutaneous mitral balloon valvuloplasty? Prevalvuloplasty and postvalvuloplasty variables that predict long-term outcome. Circulation 2002;105:1465-71.  Back to cited text no. 43
    
44.
Kumar N, Kumar M, Duran CM. A revised terminology for recording surgical findings of the mitral valve. J Heart Valve Dis 1995;4:70-5.  Back to cited text no. 44
    
45.
Sherif MA, Paranskaya L, Yuecel S, Kische S, Thiele O, D'Ancona G, et al. MitraClip step by step; how to simplify the procedure. Neth Heart J 2017;25:125-30.  Back to cited text no. 45
    
46.
Maisano F, Franzen O, Baldus S, Schäfer U, Hausleiter J, Butter C, et al. Percutaneous mitral valve interventions in the real world: Early and 1-year results from the ACCESS-EU, a prospective, multicenter, nonrandomized post-approval study of the MitraClip therapy in Europe. J Am Coll Cardiol 2013;62:1052-61.  Back to cited text no. 46
    
47.
Schillinger W, Athanasiou T, Weicken N, Berg L, Tichelbäcker T, Puls M, et al. Impact of the learning curve on outcomes after percutaneous mitral valve repair with MitraClip and lessons learned after the first 75 consecutive patients. Eur J Heart Fail 2011;13:1331-9.  Back to cited text no. 47
    
48.
García-Fernández MA, Cortés M, García-Robles JA, Gomez de Diego JJ, Perez-David E, García E, et al. Utility of real-time three-dimensional transesophageal echocardiography in evaluating the success of percutaneous transcatheter closure of mitral paravalvular leaks. J Am Soc Echocardiogr 2010;23:26-32.  Back to cited text no. 48
    
49.
Adams DH, Anyanwu AC, Rahmanian PB, Abascal V, Salzberg SP, Filsoufi F, et al. Large annuloplasty rings facilitate mitral valve repair in Barlow's disease. Ann Thorac Surg 2006;82:2096-100.  Back to cited text no. 49
    
50.
Adams DH, Anyanwu AC. Seeking a higher standard for degenerative mitral valve repair: Begin with etiology. J Thorac Cardiovasc Surg 2008;136:551-6.  Back to cited text no. 50
    
51.
Obadia JF, Messika-Zeitoun D, Leurent G, Iung B, Bonnet G, Piriou N, et al. Percutaneous repair or medical treatment for secondary mitral regurgitation. N Engl J Med 2018;379:2297-306.  Back to cited text no. 51
    
52.
Schillinger W, Athanasiou T, Weicken N, Berg L, Tichelbäcker T, Puls M, et al. Impact of the learning curve on outcomes after percutaneous mitral valve repair with MitraClip and lessons learned after the first 75 consecutive patients. Eur J Heart Fail 2011;13:1331-9.  Back to cited text no. 52
    
53.
Guo Y, He Y, Zhang Y, Ge S, Sun L, Liu W, et al. Assessment of the mitral valve coaptation zone with 2D and 3D transesophageal echocardiography before and after mitral valve repair. J Thorac Dis 2018;10:283-90.  Back to cited text no. 53
    
54.
Faletra FF, Demertzis S, Pedrazzini G, Murzilli R, Pasotti E, Muzzarelli S, et al. Three-dimensional transesophageal echocardiography in degenerative mitral regurgitation. J Am Soc Echocardiogr 2015;28:437-48.  Back to cited text no. 54
    
55.
Zamorano J, Perez de Isla L, Sugeng L, Cordeiro P, Rodrigo JL, Almeria C, et al. Non-invasive assessment of mitral valve area during percutaneous balloon mitral valvuloplasty: Role of real-time 3D echocardiography. Eur Heart J 2004;25:2086-91.  Back to cited text no. 55
    
56.
Vegas A. Three-dimensional transesophageal echocardiography: Principles and clinical applications. Ann Card Anaesth 2016;19:S35-43.  Back to cited text no. 56
[PUBMED]  [Full text]  
57.
Wunderlich NC, Beigel R, Siegel RJ. Management of mitral stenosis using 2D and 3D echo-Doppler imaging. JACC Cardiovasc Imaging 2013;6:1191-205.  Back to cited text no. 57
    
58.
Katz WE, Conrad Smith AJ, Crock FW, Cavalcante JL. Echocardiographic evaluation and guidance for MitraClip procedure. Cardiovasc Diagn Ther 2017;7:616-32.  Back to cited text no. 58
    
59.
Cavalcante JL, Rodriguez LL, Kapadia S, Tuzcu EM, Stewart WJ. Role of echocardiography in percutaneous mitral valve interventions. JACC Cardiovasc Imaging 2012;5:733-46.  Back to cited text no. 59
    
60.
Mantovani F, Clavel MA, Vatury O, Suri RM, Mankad SV, Malouf J, et al. Cleft-like indentations in myxomatous mitral valves by three-dimensional echocardiographic imaging. Heart 2015;101:1111-7.  Back to cited text no. 60
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10], [Figure 11], [Figure 12], [Figure 13], [Figure 14], [Figure 15], [Figure 16], [Figure 17], [Figure 18], [Figure 19], [Figure 20], [Figure 21]
 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Conclusion
Real-Time Three-...
Paravalvular Lea...
Mitraclip (Edge-...
Three-Dimensiona...
Mitraclip (Edge-...
Three-Dimensiona...
Mitraclip (Edge-...
Introduction
Mitral Valve
Mitraclip (Edge-...
Mitral valve pro...
Mitral Valve Annulus
Mitral Valve Lea...
Subvalvular Appa...
Mitral Stenosis
Mitral Regurgitation
References
Article Figures
Article Tables

 Article Access Statistics
    Viewed360    
    Printed31    
    Emailed0    
    PDF Downloaded104    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]