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

Role of 3D Transesophageal Echocardiography for Transcatheter Mitral Valve Repair—A Mini Review

Edge-to-edge transcatheter mitral valve repair (TMVr) using MitraClip has been evolving rapidly in patients with severe mitral regurgitation (MR) at high surgical risk or having contraindications for surgery. Three-dimensional (3D) echocardiography plays an important role in the management of severe MR. In particular, 3D transesophageal echocardiography (TEE) imaging allows the evaluation of MV geometry and quantification of MR severity with dedicated software. Real-time 3D TEE is also commonly used to guide TMVr and facilitate the procedure. Further development of 3D echocardiography may help achieve safer and more beneficial results. The following article summarizes the current knowledge and the future perspectives of 3D TEE in TMVr.

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.

Mitral Annulus Segmentation Using Deep Learning in 3-D Transesophageal Echocardiography

3D Transesophageal Echocardiography is an excellent tool for evaluating the mitral valve and is also well suited for guiding cardiac interventions. We introduce a fully automatic method for mitral annulus segmentation in 3D Transesophageal Echocardiography, which requires no manual input. One hundred eleven multi-frame 3D transesophageal echocardiography recordings were split into training, validation, and test sets. Each 3D recording was decomposed into a set of 2D planes, exploiting the symmetry around the centerline of the left ventricle. A deep 2D convolutional neural network was trained to predict the mitral annulus coordinates, and the predictions from neighboring planes were regularized by enforcing continuity around the annulus. Applying the final model and post-processing to the test set data gave a mean error of 2.0 mm - with a standard deviation of 1.9 mm. Fully automatic segmentation of the mitral annulus can alleviate the need for manual interaction in the quantification of an array of mitral annular parameters and has the potential to eliminate inter-observer variability.

Crossed Swords Sign: A 3-Dimensional Echocardiographic Appearance

Intraoperative evaluation of mitral regurgitation is a complex undertaking. Bileaflet prolapse/flail can result in divergent mitral regurgitation jets with a characteristic "crossed swords sign" appearance. We present a case of divergent mitral regurgitation jets that were detected intraoperatively and evaluated using 3-dimensional imaging. The accurate assessment of eccentric mitral regurgitation jets, especially bilateral eccentric mitral regurgitation jets, is challenging before surgical repair. Intraoperative 3-dimensional transesophageal echocardiography with and without color-flow Doppler can significantly improve the localization of the anatomical lesion.

[Evaluation of mitral regurgitation : How much quantification do we need?]

Severe mitral regurgitation (MR) is associated with increased morbidity and mortality. Thus, the correct evaluation of the underlying etiology, pathomechanism and severity is crucial for optimal treatment. Echocardiography is the predominant diagnostic modality in the clinical routine as it enables grading of mitral regurgitation, which can frequently be achieved by readily available qualitative parameters. Additionally, echocardiography provides several methods to quantify the hemodynamic significance of MR. The effective regurgitation orifice area (EROA) is the quantitative parameter best correlated with clinical events. American and European imaging guidelines both recommend the use of quantitative parameters even though they disagree on the cut-off values for secondary MR. The evaluation of MR should always include an assessment of the adjacent heart chambers in order to be able to assess the impact of volume overload on size and function of the left ventricle and left atrium. The final interpretation of the quantitative parameters requires knowledge of left ventricular volume and ejection fraction. Newer 3D-echocardiographic approaches to quantify MR are less dependent on mathematical assumptions and have shown convincing results in several studies but still lack sufficient clinical validation. As an alternative to echocardiography, for specific indications cardiac magnetic resonance imaging (MRI) has proven to be a systematic and observer-independent method for quantification of MR.

Mechanisms of mitral regurgitation after percutaneous mitral valve repair with the MitraClip

Aims

We sought to find the morphological mechanisms of recurrent mitral regurgitation (MR) after MitraClip procedure using 3D transoesophageal echocardiography (TOE).

Methods and results

Of 478 consecutive patients treated with the initial MitraClip procedure, 41 patients who underwent repeat mitral valve (MV) transcatheter or surgical intervention for recurrent MR were retrospectively reviewed. Using 3D-TOE, we investigated morphological changes of MV leading to repeat MV intervention. Aetiology of MR at the index intervention was primary in 24 (59%) and secondary in 17 (41%) patients. In the primary MR group, worsening leaflet prolapse at the clip site caused recurrent MR in 12 (50%) patients, while 7 (29%) patients had a leaflet tear at the clip site. Acute single leaflet device detachment was seen in four patients and one patient had recurrent MR between the plug and the clip. In secondary MR, left ventricular (LV)/left atrial dilation caused recurrent MR in 13 (76%) patients. Significant increase in the LV end-diastolic volume and tenting height were observed from post-index procedure to repeat intervention (LV end-diastolic volume; from 205 to 237 ml, P &lt; 0.001, tenting height; from 0.8 to 1.3 cm, P &lt; 0.001). New emergent leaflet prolapse/flail was seen in 3 (18%) patients, suggesting iatrogenic MR.

Conclusion

Mechanisms of recurrent MR after MitraClip procedure varied and depended on the underlying MV pathology: in primary MR, worsening mitral leaflet prolapse and in secondary MR, progressive LV dilation with worsening tenting were the main causes of recurrent MR.

Application of trans-thoracic echocardiography and coronary CT angiography to diagnose mitral valve prolapse

Objective

At present, multi-detector cardiac CT has been widely applied in the detection of heart valve morphology and function. This study aims to compare the coronary CT angiography and trans-thoracic echocardiography for patients with mitral valve prolapse.

Methods

CT angiography and trans-thoracic echocardiography were adopted to detect the movement range and thickness of valvula bicuspidalis. The ultrasonic parameters of CT angiography were considered as standard reference value.

Results

Receiver operating characteristic (ROC) curve showed that the area of mitral valve motion amplitude under ROC curve was 95% detected by CT angiography with statistical significance (P < 0.001). Based on the intercept point on the ROC curve, the sensitivity and accuracy of mitral valve amplitude detected by CT angiography was 69.2 and 95.6%, the false positive and false negative rate was 5.2 and 32.4%, the predicted value of positive and negative was 92.9 and 76.9% and the consistency rate of motion range and leaf thickness detected by CT angiography was 83.3 and 47.5%. Trans-thoracic echocardiography showed that the thickness and motion range of mitral leaflet was (1.95 ± 0.22) mm and (1.5 ± 2.28) mm. The thickness and motion range of mitral leaflet that detected by CT was (2.00 ± 0.54) mm and (3.76 ± 2.1) mm.

Conclusion

The accuracy and reliability of CT angiography for patients with mitral valve prolapse are higher than those of trans-thoracic echocardiography.

Three-Dimensional Mitral Valve Morphology in Children and Young Adults With Marfan Syndrome

BACKGROUND

Mitral valve (MV) prolapse is common in children with Marfan syndrome (MFS) and is associated with varying degrees of mitral regurgitation (MR). However, the three-dimensional (3D) morphology of the MV in children with MFS and its relation to the degree of MR are not known. The goals of this study were to describe the 3D morphology of the MV in children with MFS and to compare it to that in normal children.

METHODS

Three-dimensional transthoracic echocardiography was performed in 27 patients (3-21 years of age) meeting the revised Ghent criteria for MFS and 27 normal children matched by age (±1 year). The 3D geometry of the MV apparatus in midsystole was measured, and its association with clinical and two-dimensional echocardiographic parameters was examined.

RESULTS

Compared with age-matched control subjects, children with MFS had larger 3D annular areas (P < .02), smaller annular height/commissural width ratios (P < .001), greater billow volumes (P < .001), and smaller tenting heights, areas, and volumes (P < .001 for all). In multivariate modeling, larger leaflet billow volume in MFS was strongly associated with moderate or greater MR (P < .01). Intra- and interuser variability of 3D metrics was acceptable.

CONCLUSIONS

Children with MFS have flatter and more dilated MV annuli, greater billow volumes, and smaller tenting heights compared with normal control subjects. Larger billow volume is associated with MR. Three-dimensional MV quantification may contribute to the identification of patients with MFS and other connective tissue disorders. Further study of 3D MV geometry and its relation to the clinical progression of MV disease is warranted in this vulnerable population.

Management of Incomplete Initial Repair in the Treatment of Degenerative Mitral Insufficiency

We sought to present our institutional protocol to manage incomplete initial repair of degenerative mitral regurgitation and to evaluate its mid-term outcomes. Eight hundred and fifteen patients with degenerative mitral insufficiency undergoing mitral valve repair were investigated in this study. The initial repair attempt was incomplete in 48 patients, leaving a degree of residual regurgitation > mild, and an elevated transmitral gradient or systolic anterior motion (SAM). These patients were further treated with medication or mitral valve re-repair or replacement under reinstituted cardiopulmonary bypass. Transesophageal echocardiographic reports and operational records were reviewed to identify morphological causes and establish management of incomplete initial repair. Mid-term outcomes of patients with re-repair and complete initial repair were evaluated and compared. Residual mitral regurgitation > mild was detected in 25 patients, an elevated transmitral gradient was detected in seven patients, and SAM was detected in 16 patients. The condition of eight patients with SAM was resolved with medication only. Mitral valve re-repair was performed in 23 patients and replacement was performed in 17, with comparable early mortality and morbidity. At 60.3 ± 25.5 months after surgery, late mitral stenosis and reoperation rate were significantly higher in re-repair patients than in patients with complete initial repair, despite comparable survival, left chamber reverse remodeling, and degree of residual regurgitation. Based on our institutional protocol, acceptable outcomes can be achieved for patients with incomplete initial mitral valve repair. Management should be tailored based on the characteristics of the mitral valve complex, expected repair durability, and operative risk.

Transesophageal echocardiography for the assessment of left atrial appendage thrombus: Study of the additional value of systematic real time 3D imaging after regular 2D evaluation

BACKGROUND

Two-dimensional transesophageal echocardiography (2DTEE) is currently validated for left atrial appendage (LAA) thrombus assessment but has some limitations.

AIMS

To evaluate the performance and interest of systematic real time three-dimensional transesophageal echocardiography (3DTEE) for LAA thrombus assessment, when performed after 2DTEE.

METHODS AND RESULTS

Consecutive patients undergoing TEE were prospectively included. LAA was first evaluated using 2DTEE, and patients were classified as "2D-NT" if no thrombus was found, "2D-T" in case of clear thrombus, or "2D-EQ" if equivocal. Then, 3DTEE of the LAA was performed and patients were similarly classified as "3D-NT," "3D-T," or "3D-EQ." Additional LAA CT scan was only performed if LAA thrombus was not clearly ruled out or confirmed by TEE. Additional value of 3DTEE after 2DTEE LAA evaluation was then assessed. We included 104 patients undergoing TEE. Agreement between 2DTEE and 3DTEE was very good for thrombus diagnosis (k = 0.936), but moderate for vacant LAA (k = 0.562) due to more frequent 2D-EQ than 3D-EQ (11.5% vs 2.9%; P = .016). 3DTEE allowed to refine the LAA status in 11 of 12 (91.7%) 2D-EQ patients: 10 3D-NT, 1 3D-T, and 1 3D-EQ. Coupling 3DTEE to 2DTEE permitted a definite LAA diagnosis in 103 of 104 (99%) vs 92 of 104 (88.5%) patients when 2DTEE was used alone (P = .002). Nine (8.7%) LAA thrombi were diagnosed, and 3 CT scan were performed.

CONCLUSION

3DTEE of the LAA is more effective for thrombus assessment than 2DTEE. 3DTEE should be particularly considered in case of equivocal 2DTEE, as it allows to reach a definite LAA diagnosis in almost all of the patients.

Current Clinical Applications of Three-Dimensional Echocardiography: When the Technique Makes the Difference

Advances in ultrasound, computer, and electronics technology have permitted three-dimensional echocardiography (3DE) to become a clinically viable imaging modality, with significant impact on patient diagnosis, management, and outcome. Thanks to the inception of a fully sampled matrix transducer for transthoracic and transesophageal probes, 3DE now offers much faster and easier data acquisition, immediate display of anatomy, and the possibility of online quantitative analysis of cardiac chambers and heart valves. The clinical use of transthoracic 3DE has been primarily focused, albeit not exclusively, on the assessment of cardiac chamber volumes and function. Transesophageal 3DE has been applied mostly for assessing heart valve anatomy and function. The advantages of using 3DE to measure cardiac chamber volumes derive from the lack of geometric assumptions about their shape and the avoidance of the apical view foreshortening, which are the main shortcomings of volume calculations from two-dimensional echocardiographic views. Moreover, 3DE offers a unique realistic en face display of heart valves, congenital defects, and surrounding structures allowing a better appreciation of the dynamic functional anatomy of cardiac abnormalities in vivo. Offline quantitation of 3DE data sets has made significant contributions to our mechanistic understanding of normal and diseased heart valves, as well as of their alterations induced by surgical or interventional procedures. As reparative cardiac surgery and transcatheter procedures become more and more popular for treating structural heart disease, transesophageal 3DE has expanded its role as the premier technique for procedure planning, intra-procedural guidance, as well as for checking device function and potential complications after the procedure.

Evaluation of left atrial volume and function using single-beat real-time three-dimensional echocardiography in atrial fibrillation patients

BACKGROUND

This study was aimed to evaluate the feasibility and accuracy of real-time three-dimensional echocardiography (RT-3DE) measurement of left atrial (LA) volume and function in comparison with two-dimensional echocardiography (2DE) measurements in atrial fibrillation (AF) patients.

METHODS

A total of 50 pairs of AF patients and healthy controls were enrolled in this study. Indexed LA end-diastole volume (ILAEDV) and indexed LA end-systolic volume (ILAESV), as well as LA function indices such as segmental LA ejection fraction (LAEF), were assessed using 2DE Simpson's method and the RT-3DE method.

RESULTS

The images showed that regional LA volume-time curves and LAEF were disordered in AF patients. ILAEDV and ILAESV were markedly increased and global LAEF was significantly decreased in AF patients compared with those in healthy controls (P < 0.01). No significant differences were found in ILAEDV, ILAESV, and LAEF levels as determined by the RT-3DE method or 2DE Simpson's method. Bland-Altman analysis showed that the two methods agreed well for measuring ILAEDV, ILAESV, and segmental LAEF.

CONCLUSION

The RT-3DE method may be a feasible and accurate method for evaluating LA volume and function of AF patients in clinical practice.

Role of echocardiography for catheter-based management of valvular heart disease

Catheter-based treatment of valvular heart disease, such as transvalvular aortic valve replacement (TAVR) or mitral clip procedure, has been increasingly accepted as a treatment choice for the past several years. Such new treatment options have been changing the management of patients with valvular heart disease drastically while socio-economic factors regarding their application need to be taken into consideration. The use of echocardiography, including transesophageal echocardiography (TEE), for such catheter-based treatments is essential for the success of the procedures. Severe hypotension after TAVR is a life-threatening emergency. Rapid assessment and diagnosis in the catheterization or hybrid laboratory is essential for safety and a positive outcome. Possible diagnoses in this critical situation would include severe left ventricular dysfunction due to coronary obstruction, cardiac tamponade, aortic rupture, acute severe aortic and/or mitral valve regurgitation, and hypovolemia due to bleeding. Although new types of TAVR valves reduce para-valvular aortic regurgitation (AR) significantly, it is still important to judge the severity of para-valvular AR correctly in the laboratory. As for mitral clip procedure, TEE is vital for guiding and monitoring the entire process. Accurate identification of the location and the geometry of the regurgitant orifice is necessary for proper placement of the clip. Real-time 3D TEE provides helpful en face view of the mitral valve and clip together to this end. Residual mitral regurgitation (MR) after the first clip is not uncommon. Quick and precise imaging of the residual MR (location and severity) with TEE is extremely important for the interventionist to place the second clip and possibly third clip properly. After the completion of the clip procedure, mitral valve stenosis and also iatrogenic atrial septal defect need to be checked by TEE. Echocardiography, especially TEE, is also vital for the success of other newer trans-catheter procedures such as device closure of para-valvular MR of the artificial valve, valve in valve procedure, and native valve replacement.

Reproducibility of a novel echocardiographic 3D automated software for the assessment of mitral valve anatomy

Background

3D transesophageal echocardiography (TEE) is superior to 2D TEE in quantitative anatomic evaluation of the mitral valve (MV) but it shows limitations regarding automatic quantification. Here, we tested the inter-/intra-observer reproducibility of a novel full-automated software in the evaluation of MV anatomy compared to manual 3D assessment.

Methods

Thirty-six out of 61 screened patients referred to our Cardiac Imaging Unit for TEE were retrospectively included. 3D TEE analysis was performed both manually and with the automated software by two independent operators. Mitral annular area, intercommissural distance, anterior leaflet length and posterior leaflet length were assessed.

Results

A significant correlation between both methods was found for all variables: intercommissural diameter (r = 0.84, p < 0.01), mitral annular area (r = 0.94, p > 0, 01), anterior leaflet length (r = 0.83, p < 0.01) and posterior leaflet length (r = 0.67, p < 0.01). Interobserver variability assessed by the intraclass correlation coefficient was superior for the automatic software: intercommisural distance 0.997 vs. 0.76; mitral annular area 0.957 vs. 0.858; anterior leaflet length 0.963 vs. 0.734 and posterior leaflet length 0.936 vs. 0.838. Intraobserver variability was good for both methods with a better level of agreement with the automatic software.

Conclusions

The novel 3D automated software is reproducible in MV anatomy assessment. The incorporation of this new tool in clinical MV assessment may improve patient selection and outcomes for MV interventions as well as patient diagnosis and prognosis stratification. Yet, high-quality 3D images are indispensable.

The role of experience in echocardiographic identification of location and extent of mitral valve prolapse with 2D and 3D echocardiography

Contradiction exists on the incremental value of two-dimensional (2D) and 3D transoesophageal echocardiography (TOE) over 2D transthoracic echocardiography (TTE) for the detection of mitral valve (MV) prolapse in readers with different echocardiographic experience. Twenty patients and five healthy persons were retrospectively identified who had undergone 2D-TTE, 2D-TOE and 3D-TOE. Fifteen (75 %) patients had surgical evidence of prolapse of the posterior MV leaflet and five patients (25 %) had a dilated MV annulus without prolapse. Three reader groups with different echocardiographic expertise (novice, trainees, cardiologists) scored thus in total 675 posterior scallops. Overall there was an improvement in agreement and Kappa values from novice to trainees to cardiologists. Diagnostic accuracies of 2D-TOE were higher than those of 2D-TTE mainly in novice readers. The incremental value of 3D-TOE over 2D-TOE was mainly seen in specificities. Time to diagnosis was dramatically reduced from 2D to 3D-TEE in all reader groups (all P < 0.001). 3D-TOE also improved the agreement (+12 to +16 %) and Kappa values (+0.14 to +0.21) in all reader groups for the exact description of P2 prolapse. Differences between readers with variable experience in determining the precise localization and extent of the prolapsing posterior MV scallops exist in particular in 2D-TTE analysis. 3D-TOE analysis was extremely fast compared to the 2D analysis methods and showed the best diagnostic accuracy (mainly driven by specificity) with identification of P1 and P3 prolapse still improving from novice to trainees to cardiologists and provided optimal description of P2 prolapse extent.

Comparison of the accuracy of cardiac computed tomography angiography and transthoracic echocardiography in the diagnosis of mitral valve prolapse

Background:

Cardiac multidetector computed tomography (MDCT) has been mainly applied in the diagnosis of valvular heart morphology and function along with the assessment of coronary artery disease. This study aimed to evaluate the diagnostic performance of coronary MDCT angiography for the diagnosis of mitral valve prolapse (MVP), as compared to transthoracic echocardiography (TTE).

Materials and Methods:

A total of 40 patients who had undergone both TTE and MDCT within a three-month period were included in the study. Two parameters of mitral valve leaflet thickness and leaflet billowing were measured using both techniques. The MDCT results were compared with those of TTE, which was the reference standard.

Results:

Implementing the Receiver Operating Characteristic (ROC) test on the data for MDCT-measured leaflet billowing received from MDCT angiography suggests that the area under the ROC curve is 96% for a declared variable, which is absolutely significant (P < 0.001), and MDCT-measured leaflet billowing is an appropriate index for the diagnosis of mitral valve prolapse. On the basis of the achieved cut-off point from the ROC analysis (which equals 2.5 mm leaftlet billowing) the MDCT-measured leaflet billowing takes a sensitivity and specificity of 68.4 and 95.2%. The false positive and false negative results are 4.8 and 31.6%. The positive and negative predictive values (PPV and NPV) of the revealed test indicate 92.9 and 76.9%, respectively. Finally, the consistency of the MDCT measured leaflet billowing for diagnosing the mitral valve prolapse is 82.5%. Based on the mentioned test, the consistency of the MDCT-measured leaflet thickness test is 47.5%.

Conclusion:

Along with the assessment of coronary arteries, the presence or absence of MVP can be reliably evaluated by MDCT angiography.

[Application fields of intraoperative transesophageal 3D echocardiography]

Intraoperative transesophageal echocardiography (TEE) is an established diagnostic tool and has to be regarded as the standard of care for intraoperative monitoring and cardiac surgical decision-making. Furthermore, intraoperative TEE is also used for monitoring and assessment of hemodynamic changes and the detection of previously unknown pathologies. In the past few years 3D-TEE has extended the spectrum of 2D-TEE by allowing pathomorphological features to be more easily and intuitively linked to the anatomy of the heart and the great vessels. Thus, a comprehensive 2D-TEE examination is favorably complemented by focused 3D-TEE. Especially during mitral valve surgery, 3D-TEE has proven its superiority in the diagnosis of the underlying pathology as demonstrated by a large number of studies in this field. This review presents the available data about the role of intraoperative 3D-TEE echocardiography and introduces practical fields of application.

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.

Real-time three-dimensional transesophageal echocardiography in the assessment of mechanical prosthetic mitral valve ring thrombosis

Although 2-dimensional (2D) transesophageal echocardiography (TEE) is the gold standard for the diagnosis of prosthetic valve thrombosis, nonobstructive clots located on mitral valve rings can be missed. Real-time 3-dimensional (3D) TEE has incremental value in the visualization of mitral prosthesis. The aim of this study was to investigate the utility of real-time 3D TEE in the diagnosis of mitral prosthetic ring thrombosis. The clinical outcomes of these patients in relation to real-time 3D transesophageal echocardiographic findings were analyzed. Of 1,263 patients who underwent echocardiographic studies, 174 patients (37 men, 137 women) with mitral ring thrombosis detected by real-time 3D TEE constituted the main study population. Patients were followed prospectively on oral anticoagulation for 25 ± 7 months. Eighty-nine patients (51%) had thrombi that were missed on 2D TEE and depicted only on real-time 3D TEE. The remaining cases were partially visualized with 2D TEE but completely visualized with real-time 3D TEE. Thirty-seven patients (21%) had thromboembolism. The mean thickness of the ring thrombosis in patients with thromboembolism was greater than that in patients without thromboembolism (3.8 ± 0.9 vs 2.8 ± 0.7 mm, p <0.001). One hundred fifty-five patients (89%) underwent real-time 3D TEE during follow-up. There were no thrombi in 39 patients (25%); 45 (29%) had regression of thrombi, and there was no change in thrombus size in 68 patients (44%). Thrombus size increased in 3 patients (2%). Thrombosis was confirmed surgically and histopathologically in 12 patients (7%). In conclusion, real-time 3D TEE can detect prosthetic mitral ring thrombosis that could be missed on 2D TEE and cause thromboembolic events.