Use of Real-time 3-dimensional Transthoracic Echocardiography in the Evaluation of Mitral Valve Disease

Clinical Utility of Three-Dimensional Echocardiography in the Evaluation of Mitral Valve Disease: Tips and Tricks

Although real-time 3D echocardiography (RT3DE) has only been introduced in the last decades, its use still needs to be improved since it is a time-consuming and operator-dependent technique and acquiring a good quality data can be difficult. Moreover, the additive value of this important diagnostic tool still needs to be wholly appreciated in clinical practice. This review aims at explaining how, why, and when performing RT3DE is useful in clinical practice.

Three-Dimensional Transthoracic Static and Dynamic Normative Values of the Mitral Valve Apparatus: Results from the Multicenter World Alliance Societies of Echocardiography Study

BACKGROUND

Recent advances in mitral valve (MV) percutaneous interventions have escalated the need for a more quantitative and comprehensive assessment of the MV, which can be best achieved using three-dimensional echocardiography. Understanding normal valve size, structure, and function is essential for differentiation of healthy from disease states. The aims of this study were to establish normative values for MV apparatus size and morphology and to determine how they vary across age, sex, and race groups using data from the World Alliance Societies of Echocardiography Normal Values Study.

METHODS

Three-dimensional volumetric data sets obtained on transthoracic echocardiography in 748 normal subjects (51% men) were analyzed using commercial MV analysis software (TomTec Imaging Systems) to determine annular and leaflet dimensions and areas. The subjects were divided into groups by sex (378 men and 370 women) and age (18 to 40 years [n = 266], 41 to 65 years [n = 249], and >65 years [n = 233]) to identify sex- and age-related differences. In addition, differences among black, white, and Asian populations were studied. Inter- and intraobserver variability was assessed in a subset of 30 subjects and expressed as mean absolute difference between pairs of repeated measurements.

RESULTS

Compared with women, men had larger annular size measurements, larger tenting size parameters, and larger leaflet length and area. Compared with the black and white populations, the Asian population showed significantly smaller mitral annular size. Although many of the age, sex, and race differences in MV parameters were statistically significant, they were comparable with or smaller than the corresponding measurement variability. Indexing to body surface area and height did not eliminate these differences consistently, suggesting that parameters may need to be indexed according to their dimensionality.

CONCLUSIONS

This analysis of the World Alliance Societies of Echocardiography data provides normative values of mitral apparatus size and morphology. Although sex- and age-related differences were noted, they need to be interpreted with caution in view of the associated measurement variability.

Three-Dimensional Echocardiography Assessment of Right Ventricular Volumes and Function: Technological Perspective and Clinical Application

Right ventricular (RV) function has important prognostic value in a variety of cardiovascular diseases. Due to complex anatomy and mode of contractility, conventional two-dimensional echocardiography does not provide sufficient and accurate RV function assessment. Currently, three-dimensional echocardiography (3DE) allows for an excellent and reproducible assessment of RV function owing to overcoming these limitations of traditional echocardiography. This review focused on 3DE and discussed the following points: (i) acquisition of RV dataset for 3DE images, (ii) reliability, feasibility, and reproducibility of RV volumes and function measured by 3DE with different modalities, (iii) the clinical application of 3DE for RV function quantification.

The Role of 2D and 3D Echo in Mitral Stenosis

Mitral stenosis is an important cause of heart valve disease globally. Echocardiography is the main imaging modality used to diagnose and assess the severity and hemodynamic consequences of mitral stenosis as well as valve morphology. Transthoracic echocardiography (TTE) is sufficient for the management of most patients. The focus of this review is the role of current two-dimensional (2D) and three-dimensional (3D) echocardiographic imaging for the evaluation of mitral stenosis.

Two-dimensional-Wilkins and real-time transesophageal three-dimensional scoring systems: Which one is preferred to mitral valve morphological assessment?

BACKGROUND

To quantify valvular morphological assessment, some two-dimensional (2D) and three-dimensional (3D) scoring systems have been developed to target the patients for balloon mitral valvuloplasty; however, each scoring system has some potential limitations. To achieve the best scoring system with the most features and the least restrictions, it is necessary to check the degree of overlap of these systems. Also the factors related to the accuracy of these systems should be studied. We aimed to determine the correlation between the 2D Wilkins and real-time transesophageal three-dimensional (RT3D-TEE) scoring systems.

METHODS

This cross-sectional study was performed on 156 patients with moderate to severe mitral stenosis who were candidates for percutaneous balloon valvuloplasty. To morphologic assessment of mitral valve, patients were examined by 2D-transthoracic echocardiography and RT3D-TEE techniques on the same day.

RESULTS

A strong association was found between total Wilkins and total RT3D-TEE scores (r = 0.809, p < 0.001). The mean mitral valve area assessed by the 2D and 3D was 1.07 ± 0.25 and 1.03 ± 0.26, respectively, indicating a mean difference of 0.037 cm² (p = 0.001). We found a strong correlation between the values of mitral valve area assessed by 2D and 3D techniques (r = 0.846, p < 0.001).

CONCLUSION

There is a high correlation between the two scoring systems in terms of evaluating dominant morphological features. Partially, mitral valve area overestimation in the 2D-transthoracic echocardiography and its inability to assess commissural involvement as well as its dependence on patient age were exceptions in this study.

Understanding Non-P2 Mitral Regurgitation Using Real-Time Three-Dimensional Transesophageal Echocardiography: Characterization and Factors Leading to Underestimation

BACKGROUND

P2 prolapse is a common cause of degenerative mitral regurgitation (MR); echocardiographic characteristics of non-P2 prolapse are less known. Because of the eccentric nature of degenerative MR jets, the evaluation of MR severity is challenging. The aim of this study was to test the hypotheses that (1) the percentage of severe MR determined by transthoracic echocardiography (TTE) would be lower compared with that determined by transesophageal echocardiography (TEE) in patients with non-P2 prolapse and also in a subgroup with "horizontal MR" (a horizontal jet seen on TTE that hugs the leaflets without reaching the atrial wall, particularly found in non-P2 prolapse) and (2) the directions of MR jets between TTE and real-time (RT) three-dimensional (3D) TEE would be discordant.

METHODS

One hundred eighteen patients with moderate to severe and severe degenerative MR defined by TEE were studied. The percentage of severe MR between TTE and TEE was compared in P2 and non-P2 prolapse groups and in horizontal and nonhorizontal MR groups. Additionally, differences in the directions of the MR jets between TTE and RT 3D TEE were assessed.

RESULTS

Eighty-six percent of patients had severe MR according to TEE. TTE underestimated severe MR in the non-P2 group (severe MR on TTE, 57%; severe MR on TEE, 85%; P < .001) but not in the P2 group (severe MR on TTE, 79%; severe MR on TEE, 91%; P = .157). Most "horizontal" MR jets were found in the non-P2 group (85%), and this subgroup showed even more underestimation of severe MR on TTE (TTE, 22%; TEE, 89%; P < .001). There was discordance in MR jet direction between two-dimensional TTE and RT 3D TEE in 41% of patients.

CONCLUSIONS

Non-P2 and "horizontal" MR are significantly underestimated on TTE compared with TEE. There is substantial discordance in the direction of the MR jet between RT 3D TEE and TTE. Therefore, TEE should be considered when these subgroups of MR are observed on TTE.

Level of agreement in three-dimensional planimetric measurement of mitral valve area between transthoracic and transesophageal echocardiography

BACKGROUND

Echocardiographic measurement of mitral valve area (MVA) is critical prior to percutaneous transmitral commissurotomy (PTMC). This study aimed to compare the agreement between transthoracic (TTE) and transesophageal echocardiography (TEE) in three-dimensional (3D) planimetric measurement of the MVA among patients with severe mitral stenosis.

METHODS

MVA was measured with planimetry in 105 patients before undergoing PTMC. 3D reconstruction was applied to both TTE and TEE examinations. The MVA values from four different methods of 3D reconstruction were compared to the average values of 3D methods in TEE as the gold standard measurement method for the MVA in this study. The agreement levels between the two examinations were evaluated and analyzed for various reconstruction methods.

RESULTS

The mean age was 49 ± 12 years for 28 men and 77 women who were enrolled. The image quality was graded as "excellent" in 57% of 3D images obtained by TTE, while it was graded as "excellent" in 81% of 3D images obtained by TEE. The ventricular zooming method in TTE with a bias of -0.006 ± 0.065 cm² (P < 0.0001) had the highest agreement with the 3D-MVA in TEE. While 2D-TTE and 3D-TEE measurements of the MVA (R = 0.91; P < 0.0001) were significantly correlated, 2D-TTE overestimated the MVA by 0.19 cm² .

CONCLUSION

Although the quality of 3D images was significantly better in TEE than those in TTE, a good agreement existed between the measured 3D-TTE and 3D-TEE studies. We also demonstrated that 2D-TTE overestimated the MVA compare to 3D-TEE.

Diagnosis of Isolated Cleft Mitral Valve Using Three-Dimensional Echocardiography

BACKGROUND

The prevalence of isolated cleft mitral valve (MV; no concomitant congenital heart disease or degenerative MV disease) with significant mitral regurgitation (MR) diagnosed using two-dimensional echocardiography (2DE) has been reported to be very low. Three-dimensional echocardiography (3DE) has enabled a more comprehensive visualization of the MV and detailed understanding of the mechanisms of MR and can potentially reveal isolated cleft MV that is not recognized with 2DE. The aim of this study was to determine, using 3DE, the prevalence, location, and associated MV annular and left ventricular characteristics of isolated cleft MV, in the absence of associated congenital heart disease, in patients with significant MR.

METHODS

A total of 1,092 patients with unexplained moderate or greater MR on two-dimensional transthoracic echocardiography who were referred for three-dimensional transesophageal echocardiography between 2005 and 2017 (n = 626) were retrospectively studied. Left ventricular dimensions and function were determined, and quantitative MR assessment and three-dimensional analysis of the MV annulus was performed.

RESULTS

Twenty-one patients (prevalence 3.3%) were diagnosed with isolated cleft MV using three-dimensional transesophageal echocardiography but not 2DE. The majority of these patients (n = 16) were noted to have anterior cleft MVs, with most located in the mid-A1 (n = 10) or mid-A3 (n = 5) scallops. Posterior clefts were less common (n = 5) and occurred at the site of the natural scallop indentations (three between P1 and P2 and two between P2 and P3). Among patients with either anterior or posterior MV cleft, there were no differences in left ventricular ejection fraction or three-dimensional MV geometry (annular distance, height, circumference, and area). There was a trend toward worse MR severity in patients with anterior cleft MV.

CONCLUSIONS

In patients with otherwise unexplained significant MR referred for transesophageal echocardiography, 3DE uncovered a considerably higher prevalence of isolated cleft MV than previously reported by 2DE, with the majority located in the anterior MV. Although the annular geometry was similar between patients with anterior and posterior cleft MVs, a trend toward more severe MR in anterior clefts may reflect underlying abnormalities in the embryologic development of the anterior MV leaflet. Evaluation of MV pathology is improved by 3DE, which should be used routinely in the setting significant MR.

Micro-beamforming with Error Compensation

One of the main issues in the development of 2D arrays is the high system complexity due to the requirement for a large number of elements. 2D array systems suffer from high system complexity. Micro-beamforming (MBF) method has been proposed to reduce the system complexity; however, distortions of MBF approach such as focusing errors of post-beamforming process results in broadening the main lobe and increasing the side-lobe and grating-lobe levels, which together degrade the image quality. As the pre-steered radio-frequency (RF) data can be estimated from MBF data at the digital back end, better post-beamforming can be performed and higher image quality can be achieved. In this study, a compensation approach is proposed to estimate the pre-steered RF data from MBF data by utilizing additional headers and compensation factors. The compensation factors and headers are estimated at the probe front end and then applied to the back-end digital system to reconstruct the required pre-steered RF data. As the absolute values of the MBF errors are modeled as a single-sided Gaussian distribution, the theoretical mean square error (MSE) with the proposed method is approximately 2.75 times lower than that of its counterpart without compensation; this implies better reconstruction of pre-steered RF data can be achieved with the proposed method. The simulation results showed that the main lobe is improved, and the side-lobe and grating-lobe levels in both the lateral and elevation directions were improved by 11.73 dB and 19.12 dB, respectively, while the peak signal-to-noise ratios improved by 6-9 dB with the proposed method. The contrast-to-noise ratios also are enhanced by 0.5 dB when using the proposed method. Analog circuits are presented to demonstrate that this novel compensation method can be realized in practice. The reduction of cables and analog-to-digital converters (ADCs) are about 7-fold compared to fully-sampled 2D array systems as 4 by 4 channels are grouped for the proposed method as well.

Mechanistic insights of the left ventricle structure and fibrosis in the arrhythmogenic mitral valve prolapse

Mitral valve prolapse (MVP) is a common and benign condition. However, some anatomic forms have been recently associated with life-threatening ventricular arrhythmias and sudden cardiac death. Imaging MVP holds the promise of individualized MVP risk assessment. Noninvasive imaging techniques available today are playing an increasingly important role in the diagnosis, prognosis and monitoring of MVP. In this article, we will review the current evidence on arrhythmogenic MVP, with special focus on the utility of echocardiography and CMR for identifying benign and "malignant" forms of MVP. The clinical relevance of this manuscript lies in the value of imaging technology to improve MVP risk prediction, including those arrhythmic-MVP cases with a higher risk of sudden cardiac death.

Mitral leaflet separation to evaluate the severity of mitral stenosis: Validation of the index by transesophageal three-dimensional echocardiography

BACKGROUND

Determining severity of mitral stenosis (MS) by planimetry of mitral valve orifice area (MVA) has been a challenging issue in clinical practice, especially for less experienced cardiologists. Mitral leaflet separation (MLS) has shown a good correlation with MVA measurements. However, it has never been validated against multiplane 3DTEE planimetry (MVA_3D ). We aimed to evaluate the accuracy of MLS index (MLSI_2D ) in predicting MS severity.

METHODS

We prospectively enrolled 144 patients with MS who underwent clinically indicated 2DTTE and 3DTEE. MLSI_2D was yield by averaging the maximal leaflet tip distance in diastole, in parasternal long-axis and apical four-chamber views. MVA_3D was used as the reference method.

RESULTS

MLSI_2D showed an excellent discriminatory ability between different grades of MS (P < .001). There was a significant positive correlation between MLSI_2D and MVA_3D (r = .93, P < .001) irrespective of concurrent mitral regurgitation (r = .94, P < .001) and/or atrial fibrillation (r = .92, P < .001). By receiver operating characteristic (ROC) curves, MLSI_2D  ≤ 8.6 mm showed 100% sensitivity and 76% specificity for very severe MS. MLSI_2D  ≥ 11.2 mm determined progressive MS with 100% sensitivity and 82% specificity. The study population was then divided into a derivation group and a validation group. A regression equation for MVA by MLSI_2D was derived in first group. Then, the MVA was calculated by this equation in validation group and was not significantly different from MVA_3D .

CONCLUSION

MLSI_2D showed an excellent ability to assess MS severity and correlates well with planimetered MVA measured by 3DTEE.

Annular dynamics after mitral valve repair with different prosthetic rings: A real-time three-dimensional transesophageal echocardiography study

PURPOSE

We assessed the effects of different types of prosthetic rings on mitral annular dynamics using real-time three-dimensional echocardiography (RT3DE).

METHODS

RT3DE was performed in 44 patients, including patients undergoing mitral annuloplasty using the Cosgrove-Edwards flexible band (Group A, n = 10), the semi-rigid Sorin Memo 3D ring (Group B, n = 17), the semi-rigid Edwards Physio II ring (Group C, n = 7) and ten control subjects. Various annular diameters were measured throughout the cardiac cycle.

RESULTS

We observed flexible anterior annulus motion in all of the groups except Group C. A flexible posterior annulus was only observed in Group B and the Control group. The mitral annular area changed during the cardiac cycle by 8.4 ± 3.2, 6.3 ± 2.0, 3.2 ± 1.3, and 11.6 ± 5.0 % in Group A, Group B, Group C, and the Control group, respectively. The dynamic diastolic to systolic change in mitral annular diameters was lost in Group C, while it was maintained in Group A, and to a good degree in Group B. In comparison to the Control group, the mitral annulus shape was more ellipsoid in Group B and Group C, and more circular in Group A.

CONCLUSION

Although mitral regurgitation was well controlled by all of the types of rings that were utilized in the present study, we demonstrated that the annulus motion and annulus shape differed according to the type of prosthetic ring that was used, which might provide important information for the selection of an appropriate prosthetic ring.

Transthoracic two-dimensional xPlane and three-dimensional echocardiographic analysis of the site of mitral valve prolapse

This study sought to assess the value of two-dimensional (2D) transthoracic echocardiography (TTE), 2D xPlane imaging and three-dimensional (3D) TTE for the definition of the site and the extent of mitral valve (MV) prolapse. Fifty patients underwent transthoracic 2D, 2D xPlane and 3D echocardiography. With 2D xPlane a segmental analysis of the MV was performed, by making a lateral sweep across the MV coaptation line as seen in the parasternal short-axis view. Inter-observer agreement for specific scallop prolapse was for 2D xPlane excellent (97 %, kappa = 0.94) and for 3D TTE moderate (85 %, kappa = 0.67). The respective sensitivities of standard 2D TTE, 2D xPlane, and 3D TTE for the identification of the precise posterior scallop prolapse were for P1 92, 85, and 92 %, for P2 96, 96, and 82 %, and for P3 86, 81, and 71 %. In total, 5 (8 %) prolapsing MV scallops were missed by 2D TTE, 7 (12 %) by 2D xPlane, and 12 (20 %) by 3D TTE. The sensitivity of 3D TTE was significantly lower than standard 2D imaging (80 % versus 93 %, P < 0.05). The extent of P2 prolapse was under or overestimated in 5 patients with 2D xPlane and in 9 patients with 3D TTE. 2D xPlane imaging is an accurate, easy to use (compared to 3D TTE) and easy to interpret (compared to 2D and 3D TTE) imaging modality to study the site and the extent of MV prolapse.

Mitral valve geometry in paediatric rheumatic mitral regurgitation

Rheumatic mitral valve disease is associated with valvulitis and valvular regurgitation; however, the effect of the rheumatic process on the mitral valve geometry and function is not well understood. To assess mitral valve annulus remodelling in rheumatic mitral valve disease, 16 subjects aged 6-15 years with rheumatic mitral valve regurgitation [MR] [6 mild or moderate (Group 1), 10 severe (Group 2)] and 7 age- and body size-matched normal controls with adequate trans-thoracic echocardiograms were recruited. None of the patients had undergone surgical intervention and none had more than mild aortic regurgitation. None of the patients had mitral stenosis. 3D mitral valve geometry was assessed using a Tomtec system. The non-planar angle was increased in all subjects during early (control 147° ± 10, Group 1 168° ± 9, Group 2 166° ± 10; p < 0.05) and late systole (control 149° ± 12, Group 1 162° ± 10, Group 2 164° ± 6; p < 0.05), indicating loss of saddle shape. 2D annular area increased in Group 2 (control 397 ± 48 mm(2)/m(2) vs Group 2 739 ± 207, p < 0.05) with no significant change in annular perimeter indicating leaflet effacement. Mitral valve area correlated with left ventricular size (p < 0.001, r (2) = 0.74). There was no significant change in valve area and perimeter between early and late systole. Remodelling of the mitral valve apparatus in childhood rheumatic heart disease results in abnormal annular geometry. The mitral valve loses its saddle shape regardless of the severity of MR. This may be a consequence of inflammation on the fibrous trigones and surrounding annulus. In contrast, annular area enlargement occurs as a result of leaflet effacement and relates to MR severity and LV size.

Role of modern 3D echocardiography in valvular heart disease

Three-dimensional (3D) echocardiography has been conceived as one of the most promising methods for the diagnosis of valvular heart disease, and recently has become an integral clinical tool thanks to the development of high quality real-time transesophageal echocardiography (TEE). In particular, for mitral valve diseases, this new approach has proven to be the most unique, powerful, and convincing method for understanding the complicated anatomy of the mitral valve and its dynamism. The method has been useful for surgical management, including robotic mitral valve repair. Moreover, this method has become indispensable for nonsurgical mitral procedures such as edge to edge mitral repair and transcatheter closure of paravaluvular leaks. In addition, color Doppler 3D echo has been valuable to identify the location of the regurgitant orifice and the severity of the mitral regurgitation. For aortic and tricuspid valve diseases, this method may not be quite as valuable as for the mitral valve. However, the necessity of 3D echo is recognized for certain situations even for these valves, such as for evaluating the aortic annulus for transcatheter aortic valve implantation. It is now clear that this method, especially with the continued development of real-time 3D TEE technology, will enhance the diagnosis and management of patients with these valvular heart diseases.

Identification of prolapsing mitral valve scallops by a three-dimensional multiplanar reconstruction method

BACKGROUND

The objectives of this study were twofold: to assess the diagnostic utility of three-dimensional (3D) multiplanar reconstruction (MPR) in identifying prolapsing mitral valve (MV) scallops, and (2) to compare two-dimensional (2D) transthoracic echocardiography (TTE) and 3DMPR to (2D) transesophageal echocardiography (TEE) approaches among patients with mitral valve prolapse (MVP).

METHODS

Fifty-five patients with MVP who underwent MV repair or replacement were retrospectively analyzed using 3 types of echocardiographic studies (2DTEE, 2DTTE, 3DMPR). The operative (OR) findings were considered the gold standard.

RESULTS

When 3DMPR was combined with 2DTTE, the agreement with the OR findings was moderately strong for the A2 scallop (P < 0.001) and strong for the A3 scallop (P = 0.001), entire anterior leaflet (P < 0.001), P2 scallop (P < 0.001) and the entire posterior leaflet (P < 0.001). In comparison to the OR findings, 2DTEE demonstrated moderately strong agreement for the A2 scallop (P = 0.010) and the entire anterior leaflet (P < 0.001), and strong agreement for the P2 scallop (P < 0.001) and entire posterior leaflet (P < 0.001).

CONCLUSIONS

Three-dimensional MPR should be added to the armamentarium of complementary echo techniques in the evaluation of MVP. There is increased benefit in combining 3DMPR with 2DTTE findings as part of the preoperative evaluation of patients with MVP.

Usefulness of intraoperative real-time three-dimensional transesophageal echocardiography for pre-procedural evaluation of mitral valve cleft: a case report

A precise pre-procedural evaluation of mitral valve (MV) pathology is essential for planning the surgical strategy for severe mitral regurgitation (MR) and preparing for the intraoperative procedure. In the present case, a 38-year-old woman was scheduled to undergo MV replacement due to severe MR. She had a history of undergoing percutaneous balloon valvuloplasty due to rheumatic mitral stenosis during a previous pregnancy. A preoperative transthoracic echocardiography suggested a tear in the mid tip of the anterior mitral leaflet. However, the "en face" view of the MV in the left atrial perspective using intraoperative real time three-dimensional transesophageal echocardiography (RT 3D-TEE) provided a different diagnosis: a torn cleft in the P2-scallop of the posterior mitral leaflet (PML) with rupture of the chordae. Thus, surgical planning was changed intraoperatively to MV repair (MVRep) consisting of patch closure of the PML, commissurotomy, and lifting annuloplasty. The present case shows that intraoperative RT 3D-TEE provides more precise and reliable spatial information of MV for MVRep and facilitates critical surgical decision-making.

Usefulness of intraoperative real-time three-dimensional transesophageal echocardiography in preprocedural evaluation of cortriatriatum -a case report-

Cortriatriatum is a rare congenital cardiac disorder with fibromuscular band (diaphragm) dividing the left atrium (LA) into the proximal and distal parts. Surgical correction of cortriatriatum requires full preoperative evaluation of the structural anomalies including the LA diaphragm and their pathophysiology. In the present case, a 44 year-old lady diagnosed as cortriatriatum underwent surgical correction. Intraoperative three-dimensional transesophageal echocardiography provided detailed information regarding the shape and extent of the LA diaphragm, which had been partially evaluated by preoperative two-dimensional transthoracic and transesophageal echocardiography, and facilitated the intraoperative patient management and surgical decision making.

Three-dimensional echocardiography of the mitral valve: lessons learned

Three-dimensional echocardiography has markedly improved our understanding of normal and pathologic mitral valve (MV) mechanics. Qualitative and quantitative analysis of three-dimensional (3D) data on the mitral valve could have a clinical impact on diagnosis, patient referral, surgical strategies, annuloplasty ring design and evaluation of the immediate and long-term surgical outcome. This review covers the contribution of 3D echocardiography in the diagnosis of MV disease, its role in selecting and monitoring surgical procedures, and in the assessment of surgical outcomes. Moreover, advantages of this technique versus the standard 2D modality, as well as future applications of advanced analysis techniques, will be reviewed.

Determination of mitral valve area with echocardiography, using intra-operative 3-dimensional versus intra- & post-operative pressure half-time technique in mitral valve repair surgery

Background

We hypothesized that mitral valve areas (MVAs) with echocardiography, using 3D planimetry technique (measured at one point at maximal opening of mitral valve) versus pressure half-time technique (PHT, measured during entire diastolic phase) in mitral valve repair surgery (MVR) would be different.

Methods

Patients who had undergone MVR were retrospectively reviewed, and two different observers measured the MVAs using PHT and 3D planimetry technique. The MVAs derived from recorded medical data, using PHT and 3D planimetry technique were abbreviated to MVA-PHT1 and MVA-3D1, and data from the PHT and 3D planimetry techniques by observer A and observer B were determined as MVA-PHT2 and MVA-3D2, and MVA-PHT3 and MVA-3D3, respectively. The MVA derived by post-operative transthoracic echocardiography using the PHT technique was determined as MVA-TTE.

Results

Intraclass correlation coefficients were 0.90 for the intra-operative PHT technique and 0.78 for the intra-operative 3D planimetry technique. MVA-3D1 (2.91 ± 0.65 cm²), MVA-3D2 (3.00 ± 0.63 cm2) and MVA-3D3 (2.97 ± 0.88 cm²) were significantly larger than MVA-TTE (2.40 ± 0.59 cm²), but intra-operative MVAs-PHT were not. The biases and precisions were larger, and the correlation coefficients were lower in 3D planimetry technique compared with PHT technique.

Conclusions

MVA measured by 3D planimetry technique with TEE at the intra-operative post-MVR period was seemed to be larger than that measured by the PHT technique with TTE at the post-operative period. However, it did not mean that the 3D planimetry technique was inaccurate but needs cautions at determination of MVA using different techniques.

Current clinical applications of transthoracic three-dimensional echocardiography

The advent of three-dimensional echocardiography (3DE) has significantly improved the impact of non-invasive imaging on our understanding and management of cardiac diseases in clinical practice. Transthoracic 3DE enables an easier, more accurate and reproducible interpretation of the complex cardiac anatomy, overcoming the intrinsic limitations of conventional echocardiography. The availability of unprecedented views of cardiac structures from any perspective in the beating heart provides valuable clinical information and new levels of confidence in diagnosing heart disease. One major advantage of the third dimension is the improvement in the accuracy and reproducibility of chamber volume measurement by eliminating geometric assumptions and errors caused by foreshortened views. Another benefit of 3DE is the realistic en face views of heart valves, enabling a better appreciation of the severity and mechanisms of valve diseases in a unique, noninvasive manner. The purpose of this review is to provide readers with an update on the current clinical applications of transthoracic 3DE, emphasizing the incremental benefits of 3DE over conventional two-dimensional echocardiography.

Real-time three-dimensional transthoracic echocardiography in daily practice: initial experience

AIM OF THE WORK

To evaluate the feasibility and possible additional value of transthoracic real-time three-dimensional echocardiography (RT3D-TTE) for the assessment of cardiac structures as compared to 2D-TTE.

METHODS

320 patients (mean age 45 ± 8.4 years, 75% males) underwent 2D-TTE and RT3D-TTE using 3DQ-Q lab software for offline analysis. Volume quantification and functional assessment was performed in 90 patients for left ventricle and in 20 patients for right ventricle. Assessment of native (112 patients) and prosthetic (30 patients) valves morphology and functions was performed. RT3D-TTE was performed for evaluation of septal defects in 30 patients and intracardiac masses in 52 patients.

RESULTS

RT3D-TTE assessment of left ventricle was feasible and reproducible in 86% of patients while for right ventricle, it was (55%). RT3D-TTE could define the surface anatomy of mitral valve optimally (100%), while for aortic and tricuspid was (88% and 81% respectively). Valve area could be planimetered in 100% for the mitral and in 80% for the aortic. RT3D-TTE provided a comprehensive anatomical and functional evaluation of prosthetic valves. RT3D-TTE enface visualization of septal defects allowed optimal assessment of shape, size, area and number of defects and evaluated the outcome post device closure. RT3D-TTE allowed looking inside the intracardiac masses through multiple sectioning, valuable anatomical delineation and volume calculation.

CONCLUSION

Our initial experience showed that the use of RT3D-TTE in the assessment of cardiac patients is feasible and allowed detailed anatomical and functional assessment of many cardiac disorders.

Comparison of 2- and 3-dimensional shoulder ultrasound to magnetic resonance imaging in a community hospital for the detection of supraspinatus rotator cuff tears with improved worktime room efficiency

PURPOSE

The purpose of this study was to evaluate whether 3-dimensional (3D) volumetric acquisition of shoulder ultrasound (US) data for supraspinatus rotator cuff tears is as sensitive when compared with conventional 2-dimensional (2D) US and routine magnetic resonance imaging (MRI), and whether there is improved workroom time efficiency when using the 3D technique compared with the 2D technique.

METHODS

In this prospective study, 39 shoulders underwent US and MRI examination of their rotator cuff to confirm the accuracy of both the 2D and 3D techniques. The difference in sensitivities was compared by using confidence interval analysis. The mean times required to obtain the 2D and 3D US data and to review the scans were compared by using a 1-tailed Wilcoxon test.

RESULTS

Sensitivity and specificity of 2D US in detecting supraspinatus full- and partial-thickness tears was 100% and 96%, and 80% and 100%, respectively, and similar values were obtained with 3D US at 100% and 100%, and 90% and 96.6%, respectively. Analysis of the confidence limits of the sensitivities showed no significant difference. The mean time (± SD) of the overall 2D examination of the shoulder, including interpretation was 10.02 ± 3.28 minutes, whereas, for the 3D examination, it was 7.08 ± 0.35 minutes. Comparison between the 2 cohorts when using a 1-tailed Wilcoxon test showed a statistically significant difference (P < .05).

CONCLUSION

3D US of the shoulder is as accurate as 2D US when compared with MRI for the diagnosis of full- and partial-thickness supraspinatus rotator cuff tears, and 3D US examination significantly reduced the time between the initial scan and the radiologist interpretation, ultimately improving workplace efficiency.

Real-time three-dimensional transesophageal echocardiography for assessment of mitral valve functional anatomy in patients with prolapse-related regurgitation

The aim of the study was to evaluate the additional diagnostic value of real-time 3-dimensional transesophageal echocardiography (RT3D-TEE) for surgically recognized mitral valve (MV) prolapse anatomy compared to 2-dimensional transthoracic echocardiography (2D-TTE), 2D-transesophageal echocardiography (2D-TEE), and real-time 3D-transthoracic echocardiography (RT3D-TTE). We preoperatively analyzed 222 consecutive patients undergoing repair for prolapse-related mitral regurgitation using RT3D-TEE, 2D-TEE, RT3D-TTE, and 2D-TTE. Multiplanar reconstruction was added to volume-rendered RT3D-TEE for quantitative prolapse recognition. The echocardiographic data were compared to the surgical findings. Per-patient analysis of RT3D-TEE identified prolapse in 204 patients more accurately (92%) than 2D-TEE (78%), RT3D-TTE (80%), and 2D-TTE (54%). Even among those 60 patients with complex prolapse (>1 segment localization or commissural lesions), RT3D-TEE correctly identified 58 (96.5%) compared to 42 (70%), 31 (52%), and 21 (35%) detected by 2D-TEE, RT3D-TTE, and 2D-TTE (p < 0.0001). Multiplanar reconstruction enabled RT3D-TEE to differentiate dominant (≥5-mm displacement) and secondary (2 to <5-mm displacement) prolapsed segments in agreement with surgically recognized dominant lesions (100%), but with a low predictive value (34%) for secondary lesions. In addition, owing to the identification of clefts and subclefts (indentations of MV tissue that extended ≥50% or <50% of the total leaflet height, respectively), RT3D-TEE accurately characterized the MV anatomy, including that which deviated from the standard nomenclature. In conclusion, RT3D-TEE provided more accurate mapping of MV prolapse than 2D imaging and RT3D-TTE, adding quantitative recognition of dominant and secondary lesions and MV anatomy details.

Utility of three-dimensional transesophageal echocardiography in the diagnosis of valvular perforations

Three-dimensional (3D) transesophageal echocardiographic (TEE) imaging is a relatively new imaging modality that is increasingly being used to characterize a variety of cardiac pathologic features. In the present study, we reviewed the 2-dimensional (2D) and 3D TEE images from our echocardiographic database to identify patients with valve perforations. A review of the 2D TEE images resulted in the identification of 11 valvular perforations (6 aortic valves, 4 mitral valves, and 1 tricuspid valve). A review of the 3D TEE images allowed for the identification of 15 valve perforations (7 aortic valves, 7 mitral valves, and 1 tricuspid valve), including 4 perforations that could not be diagnosed using 2D imaging alone. In conclusion, 3D TEE imaging provided added benefit to traditional 2D TEE imaging because of its ability to provide en face visualization of the cardiac valves, allowing improved identification and precise anatomic localization of the perforation.

Valve anatomy and function with transthoracic three-dimensional echocardiography: advantages and limitations of instantaneous full-volume color Doppler imaging

Three-dimensional echocardiography (3DE) is becoming part of everyday clinical practice worldwide. However, 3DE requires adequate electrocardiographic and respiratory gating and it complements instead of replacing bidimensional echocardiography (2D). The instantaneous full-volume echocardiography technique is trying to overcome some of these limitations and to present an effective alternative to 2D echocardiography. In this article we aim to review the contribution of 3DE to our knowledge of anatomic and functional valvular anatomy and the potential advantages of instantaneous full-volume color Doppler echocardiography.

[Evaluation of the mitral valve by transthoracic real-time three-dimensional echocardiography]

Recently, echocardiography is the most widely used routine non-invasive diagnostic method, with which morphology and function of the mitral valve can be characterized. The aim of this review is to demonstrate the role of one of the newest echocardiographic developments, the transthoracic real-time three-dimensional echocardiography in the evaluation of mitral valve.

Pre-operative transthoracic real-time three-dimensional echocardiography in patients undergoing mitral valve repair: accuracy in cases with simple vs. complex prolapse lesions

AIMS

The aim of this study, undertaken in patients who underwent mitral valve (MV) repair surgery, was to evaluate the accuracy of pre-operative three-dimensional (3D) transthoracic echocardiography (TTE) in the evaluation of MV pathology in cases with simple or complex lesions.

METHODS AND RESULTS

Two hundred consecutive patients with severe mitral regurgitation due to degenerative MV prolapse underwent a complete 3DTTE the day before surgery. Three-dimensional TTE data were compared with MV surgical inspection. Three-dimensional echocardiography was feasible in a relatively short time (5 ± 3 min) with good (67%) and optimal (21%) imaging quality in the majority of cases. Three-dimensional TTE allowed an accurate identification (95% accuracy) of all MV lesions. Seventy-three (36.5%) patients had simple lesions at 3DTTE and 71 of them (97.2%) underwent a simple surgical procedure; 127 (63.5%) had complex lesions at 3DTTE and, in these cases, surgeons performed either simple procedures (48%) or complex procedures (47.2%) or valve replacement in 4.7% (after a first attempt for repair).

CONCLUSION

Three-dimensional TTE is feasible, not time-consuming, and accurate in identifying cases with simple vs. complex MV lesions.

Mitral valve regurgitation and 3D echocardiography

The mitral valve is a complex, dynamic and functional apparatus that can be altered by a wide range of disorders leading to stenosis or regurgitation. Surgical management of mitral valve disease may be difficult. Planned intervention may not always be feasible when the surgeon is faced with complex pathology that cannot be assessed fully by conventional 2D echocardiography. Transthoracic and transesophageal 3D echocardiography can provide a more reliable functional and anatomical assessment of the different valve components and evaluation of its geometry, which can aid the surgeon in planning a more suitable surgical intervention and improve outcomes. Although 3D echocardiography is a new technology, it has proven to be an important modality for the accurate assessment of valvular heart disease and in the future, it promises to be an essential part in the routine assessment of cardiovascular patients.

Validation of a new score for the assessment of mitral stenosis using real-time three-dimensional echocardiography

BACKGROUND

The aim of this study was to validate a new real-time three-dimensional echocardiography (RT3DE) score for evaluating patients with mitral stenosis (MS).

METHODS

A two-staged study was conducted. In the first stage, the feasibility of a new RT3DE score was assessed in 17 patients with MS. The second stage was planned to validate the RT3DE score in 74 consecutive patients undergoing percutaneous mitral valvuloplasty. The new RT3DE score was constructed by dividing each mitral valve (MV) leaflet into 3 scallops and was composed of 31 points (indicating increasing abnormality), including 6 points for thickness, 6 for mobility, 10 for calcification, and 9 for subvalvular apparatus involvement. The total RT3DE score was calculated and defined as mild (<8), moderate (8-13), or severe (>or=14). MV morphology was assessed using Wilkins's score and compared with the new RT3DE score.

RESULTS

In the first stage, the RT3DE score was feasible and easily applied to all patients, with good interobserver and intraobserver agreement. In the second stage, RT3DE improved MV morphologic assessment, particularly for the detection of calcification and commissural splitting. Both scores were correlated for assessment of thickness and calcification (r = 0.63, P < .0001, and r = 0.44, P < .0001, respectively). Predictors of optimal percutaneous mitral valvuloplasty success by Wilkins's score were leaflet calcification and subvalvular apparatus involvement, and those by RT3DE score were leaflet mobility and subvalvular apparatus involvement. The incidence and severity of mitral regurgitation were associated with high-calcification RT3DE score.

CONCLUSION

The new RT3DE score is feasible and highly reproducible for the assessment of MV morphology in patients with MS. It can provide incremental prognostic information in addition to Wilkins's score.