Misidentification of the True Aortic Annulus With 2-dimensional Echocardiography: A Critical Appraisal Using 3-Dimensional Imaging.

OBJECTIVES: This study aimed to evaluate the accuracy of identifying the true aortic valve (AV) annulus using 2-dimensional (2D) echocardiography, with the goal of highlighting potential misidentification issues in clinical practice. DESIGN: An observational study employing 3-dimensional (3D) datasets to generate 2D images of the AV annulus for analysis. SETTING: The study was conducted in an academic medical center. PARTICIPANTS: Three-dimensional transesophageal echocardiography datasets were obtained from 11 patients with normal AV and aortic root anatomies undergoing coronary artery bypass surgery. Attending anesthesiologists certified by the National Board of Echocardiography (NBE) were approached subsequently to participate in this study. INTERVENTIONS: Two images per patient were generated from 3D datasets, reflecting the mid-esophageal long-axis view of the AV, a true AV annulus image, and an off-axis image. A survey was distributed to NBE-certified perioperative echocardiographers across 12 academic institutions to identify the true AV annulus from these images. MEASUREMENTS AND MAIN RESULTS: The survey, completed by 45 qualified respondents, revealed a significant misidentification rate of the true AV annulus, with only 36.8% of responses correctly identifying it. The rate of correct identification varied across image sets, with 44.4% of participants unable to correctly identify any true AV annulus image. CONCLUSIONS: The study highlighted the limitations of 2D echocardiography in accurately identifying the true AV annulus in complex 3D structures like the aortic root. The findings suggest a need for greater reliance on advanced imaging modalities, such as 3D echocardiography, to improve accuracy in clinical practice.

Measurement of Left Ventricular Dimensions and Ejection Fraction in Neonates by Three-Dimensional Echocardiography: A Comparative Study Between Philips QLAB and TOMTEC Software-Are the Values Interchangeable?

Three-dimensional echocardiography is being used to evaluate left ventricular dimensions and ejection fraction in clinical practice. The validity and normal values have been established in a large group of normal adults, children and neonates. The aim of this study was to compare left ventricular dimensions and ejection fraction obtained from the same 3-dimensional echocardiography datasets using 2 commercially available applications: Philips QLAB and Tomtec 4D LEFT VENTRICLE-ANALYSIS. Fifty consecutive newborns or neonates coming to their first newborn visit within the first 3 weeks of live, were recruited. 38 babies underwent full Echocardiographic evaluation, including the acquisition of several 3-dimensional datasets, while naturally sleeping. Left ventricular dimensions, volumes and ejection fraction were measured using Philips QLAB version 9.0 and results were compared to results of the same datasets, analysed using TomTec 4D LV software. Mean left ventricular diastolic, and systolic volumes indexed to body surface area and ejection fraction were: 24.7 ± 3.6 ml/m2, 9.2 ± 1.3 ml/m2 and 62 ± 3.8% using TomTec and 26.6 ± 3.8 ml/m2, 10.4 ± 2 ml/m2 and 63 ± 3.1% using QLAB, respectively. Mean indexed left ventricular diastolic, and systolic volumes measured with QLAB were significantly higher as compared to TomTec with insignificant difference in the ejection fraction. Normal left ventricular indices obtained from 3-dimensional echocardiography datasets were established, using Philips QLAB and TomTec 4D LV ANALYSIS software. Measurements obtained were significantly different between those venders, and hence, may not be used interchangeably.

A Novel 3-Dimensional Approach for the Echocardiographic Evaluation of Mitral Valve Area After Repair for Degenerative Disease.

BACKGROUND: Currently available 2-dimensional (2D) echocardiographic methods for accurately assessing the mitral valve orifice area (MVA) after mitral valve repair (MVr) are limited due to its complex 3-dimensional (3D) geometry. We compared repaired MVAs obtained with commonly used 2D and 3D echocardiographic methods to a 3D orifice area (3DOA), which is a novel echocardiographic measurement and independent of geometric assumptions. METHODS: Intraoperative 2D and 3D transesophageal echocardiography (TEE) images from 20 adult cardiac surgery patients who underwent MVr for mitral regurgitation obtained immediately after repair were retrospectively reviewed. MVAs obtained by pressure half-time (PHT), 2D planimetry (2DP), and 3D planimetry (3DP) were compared to those derived by 3DOA. RESULTS: MVAs (mean value ± standard deviation [SD]) after MVr were obtained by PHT (3 ± 0.6 cm), 2DP (3.58 ± 0.75 cm), 3D planimetry (3DP; 2.78 ± 0.74 cm), and 3DOA (2.32 ± 0.76 cm). MVAs obtained by the 3DOA method were significantly smaller compared to those obtained by PHT (mean difference, 0.68 cm; P = .0003), 2DP (mean difference, 1.26 cm; P < .0001), and 3DP (mean difference, 0.46 cm; P = .003). In addition, MVA defined as an area ≤1.5 cm was identified by 3DOA in 2 patients and by 3DP in 1 patient. CONCLUSIONS: Post-MVr MVAs obtained using the novel 3DOA method were significantly smaller than those obtained by conventional echocardiographic methods and may be consistent with a higher incidence of MVA reduction when compared to 2D techniques. Further studies are still needed to establish the clinical significance of 3D echocardiographic techniques used to measure MVA after MVr.

3-Dimensional Echocardiography and 2-D Strain Analysis of Left Ventricular, Left Atrial and Right Ventricular Function in Healthy Brazilian Volunteers / Análise da Função Ventricular Esquerda e Direita e Atrial Esquerda pelo Ecocardiograma Tridimensional e Análise da Deformação Bidimensional em Voluntários Saudáveis Brasileiros

Abstract Background: New echocardiographic techniques are used in the diagnosis and prognosis of many heart diseases. However, reference values in different populations are still needed for several of these new indexes. We studied these new echocardiographic parameters in a group of Brazilians with no known cardiovascular disease. Objective: To study values for new echocardiographic indexes in Brazilians without known cardiovascular disease and their correlation with age. Methods: Cross-sectional study that included healthy individuals who underwent three-dimensional echocardiography (3DE) and two-dimensional speckle tracking echocardiography (STE) strain (e) analysis. Left atrial (LA) and left ventricular (LV) function were analyzed by 3DE and STE, and right ventricular (RV) function by STE. P values < 0.05 were considered significant. Results: Seventy-seven subjects (46.7% men; 40.4 ± 10.4 years) were included. Maximum, minimum and pre-atrial contraction (pre-A) LA volumes (ml/m2) were 21.2 ± 5.5, 7.8 ± 2.5, and 11.0 ± 3.1, respectively. Peak positive global LA e (LAScd), peak negative global LA e and total global LA e (LASr) were 17.4 ± 5.2%, -13.2 ± 2.0% and 30.5 ± 5.9%, respectively. LV end-diastolic and end-systolic volumes (ml/m2) measured 57 ± 12 and 24 ± 6, and 3D LV ejection fraction measured 58 ± 6%. Global LV longitudinal, circumferential and radial e were -19 ± 2%, -19 ± 3%, and 46 ± 12%, respectively. LV torsion measured 1.6 ± 0.70 /cm. Global longitudinal RV e (RV-GLS) and RV free wall strain were -22 ± 3% and -24 ± 5%. Minimum LA and pre-A volumes, LV apical rotation, torsion and RV-GLS increased with age, while total and passive LA emptying fractions, LAScd, LASr, LV end-diastolic and end-systolic volumes decreased with age. Conclusion: Values for new echocardiographic indexes in Brazilians without known cardiovascular disease and their correlation with age are presented.

Resumo Fundamentos: Novas técnicas ecocardiográficas são utilizadas no diagnóstico e prognóstico de diversas cardiopatias. No entanto, muitos desses novos índices ainda carecem de valores de referência em diferentes populações. Estudamos esses novos parâmetros ecocardiográficos em um grupo de brasileiros sem doença cardiovascular conhecida. Objetivo: Estudar valores dos novos índices ecocardiográficos em brasileiros sem doença cardiovascular conhecida e sua correlação com a idade. Métodos: Estudo transversal composto por indivíduos saudáveis que realizaram ecocardiograma tridimensional (E3D) e ecocardiograma bidimensional com análise de deformação (e) por speckle tracking (EST). Foram analisadas as funções atrial esquerda (AE) e ventricular esquerda (VE) por E3D e EST, e a função ventricular direita (VD) por EST. Valores de p < 0,05 foram considerados significantes. Resultados: Foram incluídos setenta e sete indivíduos (46,7% homens; 40,4 ± 10,4 anos). Os volumes AE máximo, mínimo e pré-contração atrial (pré-A) (ml/m2) foram 21,2 ± 5,5, 7,8 ± 2,5 e 11,0 ± 3,1, respectivamente. O pico da e global positiva do AE (LAScd), pico da e global negativa do AE e e global total do AE (LASr) foram 17,4±5,2%, -13,2 ± 2,0% e 30,5 ± 5,9%, respectivamente. Os volumes diastólico final e sistólico final do VE (ml/m2) mediram 57 ± 12 e 24 ± 6 e a fração de ejeção tridimensional do VE mediu 58 ± 6%. A e longitudinal, circunferencial e radial global do VE foi de -19 ± 2%, -19 ± 3% e 46 ± 12%, respectivamente. A torção do VE mediu 1,6 ± 0,7(0)/cm. A e longitudinal global do VD (SLG-VD) e a deformação da parede livre do VD foram de -22 ± 3% e -24 ± 5%. Os volumes mínimo e pré-A do AE, rotação apical do VE, torção e SLG-VD aumentaram com a idade, enquanto as frações de esvaziamento total e passivo do LA, LAScd, LASr, volumes diastólico final e sistólico final do VE diminuíram com a idade. Conclusão: Apresentam-se os valores para os novos índices ecocardiográficos em brasileiros sem doença cardiovascular conhecida e sua correlação com a idade.

The Use of Intraoperative Three-Dimensional Echocardiography to Evaluate Origin of Bioprosthetic Aortic Valve Regurgitant Jets.

Degradation of bioprosthetic aortic valves can eventually lead to both paravalvular and intravalvular regurgitation. However, differentiating between the two may be difficult in the case of multiple lesions in close proximity or highly eccentric jets. Whereas such exact distinction may be of little procedural significance in open cardiac surgery, it is of crucial importance when approaching such lesions in the catheterization laboratory or hybrid operating room. Interventions on one lesion often have a significant effect on the other. For example, guidewires may damage new bioprosthetic valve leaflets and dislodge vascular plugs. Even more concerning is the possibility of undergoing a lengthy and risky procedure on a lesion that does not truly exist. Fortunately, the use of three-dimensional Doppler echocardiography can expand our vision beyond the single imaging plane of a standard two-dimensional examination, allowing extensive manipulation of cutting planes and a wider field of view. Regurgitant jets can thus be tracked in a way that may be otherwise impossible, better quantifying their true origins. Here the authors present a unique case of misdiagnosis after surgical aortic valve degradation, where the use of intraoperative three-dimensional echocardiography significantly altered the preoperative plan and reduced operative time.

Accuracy of three-dimensional systolic dyssynchrony and sphericity indexes for identifying early left ventricular remodeling after acute myocardial infarction.

OBJECTIVE: Left ventricle (LV) geometry and dyssynchrony are associated with LV remodeling after acute myocardial infarction (AMI). The aim of this prospective study was to assess the diagnostic value of new three-dimensional echocardiography (3DE) parameters [sphericity (SI) and systolic dyssynchrony indexes (SDI)] for the prediction of LV remodeling after AMI and to compare them with two-dimensional echocardiography (2DE) parameters. METHODS: 2DE and 3DE were performed in 75 patients with AMI within 3 days from the onset of MI and 6 months later. LV remodeling was defined as a ≥15% increase in the LV end-diastolic volume (EDV) at follow-up. 3D SI was calculated by dividing EDV by the volume of a sphere whose diameter was derived from the major end-diastolic LV long axis. SDI was considered as a standard deviation of the time from cardiac cycle onset to minimum systolic volume in 16 LV segments. RESULTS: LV remodeling was identified in 34 (45%) patients using the 2DE method and in 22 (29%) patients using the 3DE method. Evaluated 3DE parameters, such as EDV [area under the receiver operating characteristic (ROC) curve (AUC) 0.742, sensitivity 71%, specificity 79%], end-systolic volume (AUC 0.729, sensitivity 69%, specificity 78%), SDI (AUC 0.777, sensitivity 73%, specificity 77%), and SI, had significant prognostic value for LV remodeling. According to the AUC, the highest predictive value had 3D SI (AUC 0.957, sensitivity 90%, specificity 91%). CONCLUSION: 3DE parameters, especially 3D SI and SDI, play important roles in the prediction of LV remodeling after AMI and can be used in clinical practice.

Validation of Quantitative 3-Dimensional Transesophageal Echocardiography Mitral Valve Analysis Using Stereoscopic Display.

OBJECTIVE: The use of 3-dimensional (3D) transesophageal echocardiography (TEE) in perioperative evaluation of the mitral valve (MV) is increasing progressively, including the use of 3D MV models for quantitative analysis. However, the use of 3D MV models in clinical practice still is limited by the need for specific training and the long time required for analysis. A new stereoscopic visualization tool (EchoPixel True 3D) allows virtual examination of anatomic structures in the clinical setting, but its accuracy and feasibility for intraoperative use is unknown. The aim of this study was to assess the feasibility of 3D holographic display and evaluate 3D quantitative measurements on a volumetric MV image using the EchoPixel system compared with the 3D MV model generated by QLAB Mitral Valve Navigation (MVN) software. DESIGN: This was a retrospective comparative study. SETTING: The study took place in a tertiary care center. PARTICIPANTS: A total of 40 patients, 20 with severe mitral regurgitation who underwent mitral valve repair and 20 controls with normal MV, were enrolled retrospectively. INTERVENTIONS: The 3D-TEE datasets of the MV were analyzed using a 3D MV model and stereoscopic display. The agreement of measurements, intraobserver and interobserver variability, and time for analysis were assessed. MEASUREMENTS AND MAIN RESULTS: Fair agreement between the 2 software systems was found for annular circumference and area in pathologic valves, but good agreement was reported for prolapse height and linear annular diameters. A higher agreement for all annular parameters and prolapse height was seen in normal valves. Excellent intraobserver and interobserver reliability was proved for the same parameters; time for analysis between the 2 methods in pathologic valves was substantially equivalent, although longer in pathologic valves when compared with normal MV using both tools. CONCLUSION: EchoPixel proved to be reliable to display 3D TEE datasets and accurate for direct linear measurement of both MV annular sizes and prolapse height compared to QLAB MVN software; it also carries a low interobserver and intraobserver variability for most measurements.

Differences in Two- and Three-Dimensional Assessment of the Mitral Valve by Novices and Experts, Illustrated Using Anterior Mitral Valve Leaflet Length.

OBJECTIVES: In this measurement validation study, the authors evaluated agreement between 2-dimensional (2D) and three-dimensional (3D) transesophageal echocardiography (TEE), measuring anterior mitral valve leaflet length by both novice and experienced echocardiographers. DESIGN: This was a retrospective, observational study. SETTING: Single university hospital. PARTICIPANTS: Analyses on datasets from 44 patients. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Fifty datasets from 44 patients with mitral regurgitation were analyzed by 4 observers (2 novices, 2 experts). All observers measured the anterior mitral valve leaflet length from end-systolic 2D TEE images from the midesophageal longitudinal axis view and 3D software-augmented TEE images. The overall mean anterior mitral valve leaflet length was significantly shorter with 3D versus 2D TEE measurements (24.6 ± 4.5 mm v 26.2 ± 5.3 mm; p < 0.001), with novices measuring shorter leaflets than experts for both techniques (p < 0.001 and p = 0.005, respectively). Bland-Altman plots of 3D and 2D TEE measurements showed mean biases (95% limits of agreement) of -1.6 mm (-9.0 to 5.9 mm), -1.8 mm (-9.6 to 6.0 mm), and -1.3 mm (-8.4 to 5.7 mm) for all observers, novices, and experts, respectively. For 2D measurements, interobserver reliability was very strong among experts and strong among novices (Pearson's r = 0.83 v 0.66; p = 0.055). For 3D measurements, interobserver reliability was strong in experts and moderate in novices (Pearson's r = 0.69 v 0.51; p = 0.168). CONCLUSION: For both novices and experts, 3D TEE measurements of the anterior mitral valve leaflet were significantly shorter than 2D measurements. Interobserver reliability was lowest for novices making 3D TEE measurements, indicating that reliable, quantitative evaluation of 3D TEE may require a greater amount of practice.

Biventricular assessment of light-chain amyloidosis using 3D speckle tracking echocardiography: Differentiation from other forms of myocardial hypertrophy.

BACKGROUND: Given that in patients with cardiac amyloidosis (CA), deposition of amyloid protein is not restricted to the left ventricular (LV) myocardium, it can be hypothesized that the diagnostic value of deformation mechanics would be enhanced by considering right ventricular (RV) strain measures. The aim of the present study was to examine the potential utility of left ventricular (LV) and right ventricular (RV) deformation and rotational parameters derived from three-dimensional speckle-tracking echocardiograph (3DSTE) to diagnose cardiac amyloidosis and differentiate this disease from other forms of myocardial hypertrophy. METHODS: Twenty-three patients with biopsy-proven light-chain (AL) amyloidosis, 23 patients with systemic arterial hypertension (HTN), 23 patients with hypertrophic cardiomyopathy (HCM), 23 athletes and 23 normal controls were prospectively studied by conventional echocardiography and 3DSTE. LV longitudinal strain (LV LS), LV circumferential strain (LV CS), RV global longitudinal strain and RV free-wall longitudinal strain (RV FW LS) were obtained by 3DSTE, as well as LV rotation and rotational velocities. RESULTS: LV and RV longitudinal strains were reduced in cardiac amyloidosis (CA) patients compared to controls. By multivariate analysis, LV basal LS (p = 0.002), LV peak basal rotation (p = 0.003), and RV basal FW LS (p = 0.014) were independently associated with CA in the overall population. A significant improvement in global χ2 value was noted with RV 3D-strain parameters over only LV-3DSTE + conventional indices for detection of CA (p < 0.001). Comparison of ROC curves showed that the AUC using combined LV basal LS, LV basal rotation and RV basal FW LS had a higher discriminative value than the other echocardiographic parameters used for detecting CA (AUC 0.93, 95%CI 0.81-0.97). CONCLUSIONS: Three-dimensional speckle tracking echocardiography reveals regional and global biventricular dysfunction in CA. Assessment of RV ventricular dysfunction has an additive value in differentiating CA from other causes of myocardial wall thickening.

Optimal surface property for three-dimensional echo visualization.

PURPOSE: Three-dimensional (3D) echo is a useful modality to guide off-pump intracardiac surgery, and this study aimed to determine the optimal surface property for minimizing echo dropout and grating lobes. METHODS: A total of 13 specimens were examined. The specimens were scanned while they were rotated from 0° to 90°, and en face views were recorded in the 3D zoom mode. Changes in brightness were compared with the surface profile, which was traced from microscopic images. The brightness and size of grating lobes were also examined. RESULTS: Decreases in brightness that were observed at a large rotation angle were classified into three groups (sharp, moderate, and gradual), and variation in the effective reflective plane size appeared to be a major determinant of this property. The same material showed different degrees of reflection depending on the surface profile. The size of grating lobes was affected by variation in the reflective plane size, but not by the intensity of reflection. The brightness of the grating lobes was similar among specimens. CONCLUSIONS: These results suggest that echo dropout and grating lobes can be effectively eliminated by an appropriate surface profile; thus, a likely practical solution would be to manufacture a surface that provides an adequate reflective surface size at various incident angles.

Standardized Delineation of Endocardial Boundaries in Three-Dimensional Left Ventricular Echocardiograms.

BACKGROUND: Three-dimensional (3D) echocardiography is fundamental for left ventricular (LV) assessment. The aim of this study was to determine discrepancies in 3D LV endocardial tracings and suggest tracing guidance. METHODS: Forty-five 3D LV echocardiographic data sets were traced by three experienced operators, from different centers, according to predefined guidelines. The 3D meshes were compared with one another, and the endocardial areas of discrepancies were identified. A discussion and retracing protocol was used to reduce discrepancies. For each data set, an average 3D mesh was produced (reference mesh). Subsequently, four novice operators, divided into two groups, traced 20 of the data sets. Two operators followed the tracing protocol and two did not. RESULTS: The intraclass correlation coefficients among the three experienced operators for end-diastolic volume, end-systolic volume, and ejection fraction were 0.952, 0.955, and 0.932. The absolute distances between tracings were 1.11 ± 0.45 mm. The highest tracing discrepancies were at the apical cap and anterior and anterolateral walls in end-diastole and end-systole and also at the basal anteroseptum in end-systole. Agreement with the reference meshes was better for the novice operators who followed the guidance (10.9 ± 17.3 mL, 10.2 ± 14.7 mL, and -2.2 ± 4.1% for end-diastolic volume, end-systolic volume, and ejection fraction) compared with those who did not (16.3 ± 16.4 mL, 17.0 ± 16.0 mL, and -4.2 ± 4.1%, respectively). CONCLUSIONS: Comparing 3D LV tracings, the endocardial areas that are the most difficult to delineate were identified. The suggested protocol for LV tracing resulted in very good agreement among operators. The reference 3D meshes are available for online testing and ranking of LV tracing algorithms.

Transesophageal Echocardiography, 3-Dimensional and Speckle Tracking Together as Sensitive Markers for Early Outcome in Patients With Left Ventricular Dysfunction Undergoing Cardiac Surgery.

OBJECTIVE: Speckle tracking, when combined with 3-dimensional (3D) left ventricular ejection fraction, might prove to be a more sensitive marker for postoperative ventricular dysfunction. This study investigated early outcomes in a cohort of patients with left ventricular dysfunction undergoing cardiac surgery. DESIGN: Prospective, blinded, observational study. SETTING: University hospital; single institution. PARTICIPANTS: The study comprised 73 adult patients with left ventricular ejection fraction <50% undergoing cardiac surgery using cardiopulmonary bypass. INTERVENTIONS: Routine transesophageal echocardiography before and after bypass. MEASUREMENTS AND MAIN RESULTS: Global longitudinal strain using speckle tracking and 3D left ventricular ejection fraction were computed using transesophageal echocardiography. Mean prebypass global longitudinal strain and 3D left ventricle ejection fraction were significantly lower in patients with postoperative low-cardiac-output syndrome compared with patients who did not develop low cardiac output (global longitudinal strain -7.5% v -10.7% and 3D left ventricular ejection fraction 29% v 39%, respectively; p < 0.0001). The cut-off value of global longitudinal strain predicting postoperative low-cardiac-output syndrome was -6%, with 95% sensitivity and 68% specificity; and 3D left ventricular ejection fraction was 19% with 98% sensitivity and 81% specificity. CONCLUSIONS: Preoperative left ventricular global longitudinal strain (-6%) and 3D left ventricular ejection fraction (19%) together could act as predictor of postoperative low-cardiac-output states with high sensitivity (99.9%) in patients undergoing cardiac surgery.

Echocardiographic Assessment of Mitral Stenosis Orifice Area: A Comparison of a Novel Three-Dimensional Method Versus Conventional Techniques.

BACKGROUND: A comprehensive evaluation of mitral stenosis (MS) severity commonly utilizes two-dimensional (2D) echocardiography techniques. However, the complex three-dimensional (3D) structure of the mitral valve (MV) poses challenges to accurate measurements of its orifice area by 2D imaging modalities. We aimed to assess MS severity by comparing measurements of the MV orifice area using conventional echocardiography methods to 3D orifice area (3DOA), a novel echocardiographic technique which minimizes geometric assumptions. METHODS: Routine 2D and 3D intraoperative transesophageal echocardiographic images from 26 adult cardiac surgery patients with at least moderate rheumatic MS were retrospectively reviewed. Measurements of the MV orifice area obtained by pressure half-time (PHT), proximal isovelocity surface area (PISA), continuity equation, and 3D planimetry were compared to those acquired using 3DOA. RESULTS: MV areas derived by PHT, PISA, continuity equation, 3D planimetry, and 3DOA (mean value ± standard deviation) were 1.12 ± 0.27, 1.03 ± 0.27, 1.16 ± 0.35, 0.97 ± 0.25, and 0.76 ± 0.21 cm, respectively. Areas obtained from the 3DOA method were significantly smaller than areas derived from PHT (mean difference 0.35 cm, P < .0001), PISA (mean difference: 0.28 cm, P = .0002), continuity equation (mean difference: 0.43 cm, P = .0015), and 3D planimetry (mean difference: 0.19 cm, P < .0001). MV 3DOAs also identified a significantly greater percentage of patients with severe MS (88%) compared to PHT (31%, P = .006), PISA (42%, P = .01), and continuity equation (39%, P = .017) but not in comparison to 3D planimetry (62%, P = .165). CONCLUSIONS: Novel measures of the stenotic MV 3DOA in patients with rheumatic heart disease are significantly smaller than calculated values obtained by conventional methods and may be consistent with a higher incidence of severe MS compared to 2D techniques. Further investigation is warranted to determine the clinical relevance of 3D echocardiographic techniques used to measure MV area.

2D Echocardiographic Evaluation of Right Ventricular Function Correlates With 3D Volumetric Models in Cardiac Surgery Patients.

OBJECTIVES: The early diagnosis and treatment of right ventricular (RV) dysfunction are of critical importance in cardiac surgery patients and impact clinical outcome. Two-dimensional (2D) transesophageal echocardiography (TEE) can be used to evaluate RV function using surrogate parameters due to complex RV geometry. The aim of this study was to evaluate whether the commonly used visual evaluation of RV function and size using 2D TEE correlated with the calculated three-dimensional (3D) volumetric models of RV function. DESIGN AND SETTING: Retrospective study, single center, University Hospital. PARTICIPANTS AND INTERVENTION: Seventy complete datasets were studied consisting of 2D 4-chamber view loops (2-3 beats) and the corresponding 4-chamber view 3D full-volume loop of the right ventricle. RV function and RV size of the 2D loops then were assessed retrospectively purely qualitatively individually by 4 clinician echocardiographers certified in perioperative TEE. Corresponding 3D volumetric models calculating RV ejection fraction and RV end-diastolic volumes then were established and compared with the 2D assessments. MEASUREMENTS AND MAIN RESULTS: 2D assessment of RV function correlated with 3D volumetric calculations (Spearman's rho -0.5; p<0.0001). No correlation could be established between 2D estimates of RV size and actual 3D volumetric end-diastolic volumes (Spearman's rho 0.15; p = 0.25). CONCLUSION: The 2D assessment of right ventricular function based on visual estimation as frequently used in clinical practice appeared to be a reliable method of RV functional evaluation. However, 2D assessment of RV size seemed unreliable and should be used with caution.

Atrial-focused views improve the accuracy of two-dimensional echocardiographic measurements of the left and right atrial volumes: a contribution to the increase in normal values in the guidelines update.

Current guidelines recommend that the atria be measured in 2D echocardiographic (2DE) apical views using the method-of-disks (MOD) or area-length (AL) technique as an alternative, although no definitive data exists that these are interchangeable. However, standard apical views maximize the long-axis of the left ventricle, rather than the dimensions of the atria, resulting in atrial foreshortening. We hypothesized that the increase in normal values of atrial volumes in the recent guidelines update was driven by data obtained using either the AL technique or dedicated atrial-focused views, which maximize the longitudinal dimension of the atria and thus provide larger volumes than the MOD measurements in standard apical views. We prospectively studied 30 patients (Philips iE33) to compare 2DE measurements of left and right atrial volumes (LAV, RAV) using the MOD and AL techniques in standard and atrial-focused views, against 3D echocardiography (3DE) derived volumes (QLab) as a reference. Compared to standard views, atrial-focused views provided significantly larger MOD volumes for both atria, which were in better agreement with 3DE, as reflected by higher correlation coefficients (LAV: r = 0.95 vs. 0.89; RAV: r = 0.89 vs. 0.84), smaller biases (LAV: -1 ml vs. 7 ml; RAV: 3 ml vs. 7 ml) and tighter limits of agreement. This was also the case for the AL measurements, which were minimally larger than the MOD values (NS) for both atria. In conclusion, atrial-focused views are a more accurate alternative to standard apical views, which provides larger volumes. This finding can explain the increase in the normal values in the recent guidelines update, which was mostly driven by the use of atrial-focused views, rather than by the differences between MOD and AL techniques. This understanding is essential in order to correctly integrate the revised normal values into clinical practice.

Three-Dimensional Field Optimization Method: Clinical Validation of a Novel Color Doppler Method for Quantifying Mitral Regurgitation.

BACKGROUND: Assessment of mitral regurgitation (MR) severity by echocardiography is important for clinical decision making, but MR severity can be challenging to quantitate accurately and reproducibly. The accuracy of effective regurgitant orifice area (EROA) and regurgitant volume (RVol) calculated using two-dimensional (2D) proximal isovelocity surface area is limited by the geometric assumptions of proximal isovelocity surface area shape, and both variables demonstrate interobserver variability. The aim of this study was to compare a novel automated three-dimensional (3D) echocardiographic method for calculating MR regurgitant flow using standard 2D techniques. METHODS: A sheep model of ischemic MR and patients with MR were prospectively examined. Patients with a range of severity of MR were examined. EROA and RVol were calculated from 3D color Doppler acquisitions using a novel computer-automated algorithm based on the field optimization method to measure EROA and RVol. For an independent comparison group, the 3D field optimization method was compared with 2D methods for grading MR in an experimental ovine model of MR. RESULTS: Fifteen 3D data sets from nine sheep (open-chest transthoracic echocardiographic data sets) and 33 transesophageal data sets from patients with MR were prospectively examined. For sheep data sets, mean 2D EROA was 0.16 ± 0.05 cm2, and mean 2D RVol was 21.84 ± 8.03 mL. Mean 3D EROA was 0.09 ± 0.04 cm2, and mean 3D RVol was 14.40 ± 5.79 cm3. There was good correlation between 2D and 3D EROA (R = 0.70) and RVol (R = 0.80). For patient data sets, mean 2D EROA was 0.35 ± 0.35 cm2, and mean 2D RVol was 58.9 ± 52.9 mL. Mean 3D EROA was 0.34 ± 0.29 cm2, and mean 3D RVol was 54.6 ± 36.5 mL. There was excellent correlation between 2D and 3D EROA (R = 0.94) and RVol (R = 0.84). Bland-Altman analysis revealed greater interobserver variability for 2D RVol measurements compared with 3D RVol using the 3D field optimization method measurements, but variability was statistically significant only for RVol. CONCLUSIONS: Direct automated measurement of proximal isovelocity surface area region for EROA calculation using real-time 3D color Doppler echocardiography is feasible, with a high correlation to current 2D EROA methods but less variability. This novel automated method provides an accurate and highly reproducible method for calculating EROA.

Three-Dimensional Field Optimization Method: Gold-Standard Validation of a Novel Color Doppler Method for Quantifying Mitral Regurgitation.

BACKGROUND: Accurate diagnosis of mitral regurgitation (MR) severity is central to proper treatment. Although numerous approaches exist, an accurate, gold-standard clinical technique remains elusive. The authors previously reported on the initial development and demonstration of the automated three-dimensional (3D) field optimization method (FOM) algorithm, which exploits 3D color Doppler ultrasound imaging and builds on existing MR quantification techniques. The aim of the present study was to extensively validate 3D FOM in terms of accuracy, ease of use, and repeatability. METHODS: Three-dimensional FOM was applied to five explanted ovine mitral valves in a left heart simulator, which were systematically perturbed to yield a total of 29 unique regurgitant geometries. Three-dimensional FOM was compared with a gold-standard flow probe, as well as the most clinically prevalent MR volume quantification technique, the two-dimensional (2D) proximal isovelocity surface area (PISA) method. RESULTS: Overall, 3D FOM overestimated and 2D PISA underestimated MR volume, but 3D FOM error had smaller magnitude (5.2 ± 9.9 mL) than 2D PISA error (-6.9 ± 7.7 mL). Two-dimensional PISA remained superior in diagnosis for round orifices and especially mild MR, as predicted by ultrasound physics theory. For slit-type orifices and severe MR, 3D FOM showed significant improvement over 2D PISA. Three-dimensional FOM processing was technically simpler and significantly faster than 2D PISA and required fewer ultrasound acquisitions. Three-dimensional FOM did not show significant interuser variability, whereas 2D PISA did. CONCLUSIONS: Three-dimensional FOM may provide increased clinical value compared with 2D PISA because of increased accuracy in the case of complex or severe regurgitant orifices as well as its greater repeatability and simpler work flow.

Intraoperative Right Ventricular Fractional Area Change Is a Good Indicator of Right Ventricular Contractility: A Retrospective Comparison Using Two- and Three-Dimensional Echocardiography.

OBJECTIVE: Intraoperative two-dimensional echocardiography is technically challenging, given the unique geometry of the right ventricle (RV). It was hypothesized that the RV fractional area change (RVFAC) could be used as a simple method to evaluate RV function during surgery. Therefore, the correlation between the intraoperative RVFAC and the true right ventricular ejection fraction (RVEF), as measured using newly developed three-dimensional (3D) analysis software, was evaluated. DESIGN: Retrospective study. SETTING: University hospital. PARTICIPANTS: Patients who underwent cardiac surgery with transesophageal echocardiography monitoring between March 2014 and June 2014. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Sixty-two patients were included in this study. After the exclusion of poor imaging data and patients with arrhythmias, 54 data sets were analyzed. RVFAC was measured by one anesthesiologist during surgery, and full-volume 3D echocardiographic data were recorded simultaneously. The 3D data were analyzed postoperatively using off-line 3D analysis software by a second anesthesiologist, who was blinded to the RVFAC results. The mean RVFAC was 38.8% ± 8.7%, the mean RVEF was 41.4% ± 8.3%, and there was a good correlation between the RVFAC and the RVEF (r(2) = 0.638; p<0.0001). CONCLUSIONS: The RVFAC was well-correlated with the RVEF calculated using 3D echocardiography; therefore, RVFAC provides a simple and useful method for anesthesiologists to evaluate intraoperative RV function.

Recommendations for comprehensive intraprocedural echocardiographic imaging during TAVR.

Recent multicenter trials have shown that transcatheter aortic valve replacement is an alternative to surgery in a high risk population of patients with severe, symptomatic aortic stenosis. Echocardiography and multislice computed tomographic imaging are accepted tools in the pre-procedural imaging of the aortic valve complex and vascular access. Transesophageal echocardiography can be valuable for intraprocedural confirmation of the landing zone morphology and measurements, positioning of the valve and post-procedural evaluation of complications. The current paper provides recommendations for pre-procedural and intraprocedural imaging used in assessing patients for transcatheter aortic valve replacement with either balloon-expandable or self-expanding transcatheter heart valves.