Reproducibility in echocardiographic two- and three-dimensional mitral valve assessment.

BACKGROUND: Three-dimensional transesophageal echocardiography (3DTEE) has been demonstrated to provide more accurate information than two-dimensional transesophageal echocardiography (2DTEE) in the localization of mitral valve prolapse (MVP). However, most studies have been single-rater studies. Few results were tested for inter-observer variability with a single second rater. This multicenter study aimed to determine reliability of 2D and 3DTEE mitral valve evaluations by calculating inter-observer agreement between various echocardiographers. METHODS: Fifteen observers from 4 institutions in Germany and Switzerland interpreted 2D and 3DTEE images from 6 patients selected to represent a large spectrum of MVP diversity. Surgical findings served as reference. Individual assessments of MVP and ruptured chordae tendineae (ChR) pathology were compared by calculating Randolph's free-marginal multirater kappa coefficient. RESULTS: Accuracy of MVP evaluation with 3DTEE was 83.9%, CI [81.0%; 86.8%] and 78.7% CI [76.6% 80.8%] with 2DTEE. Flail leaflets with chordal ruptures were described correctly in 91.1%, CI [85.8, 96.4] with 3D compared to 71.1%, CI [65.0, 77.2] with 2DTEE. The multirater kappa coefficient of inter-observer agreement among all 15 observers was κ = 0.65/0.58 for 3D/2D evaluation of MVP and κ = 0.70/0.54 for detection of ChR. CONCLUSION: Three-dimensional assessment of MVP was superior to 2DTEE, although the accuracy of both 3DTEE and 2DTEE was found to be lower than previously published. 3D MVP assessment is less operator dependent than 2DTEE evaluation. Although validity has been demonstrated before, we provide evidence that 3DTEE is reproducible among 15 observers and is a reliable method for MVP evaluation.

Image quality influences the assessment of left ventricular function: an intraoperative comparison of five 2-dimensional echocardiographic methods with real-time 3-dimensional echocardiography as a reference.

OBJECTIVES: Transesophageal echocardiography has become a standard tool for evaluating left ventricular function during cardiac surgery. However, the image quality varies widely between patients and examinations. The aim of this study was to investigate the influence of the image quality on 5 commonly used 2-dimensional methods. METHODS: Transesophageal real-time 3-dimensional echocardiography (3DE) served as a reference. Left ventricular function was evaluated in 63 patients with sufficient real-time 3DE image quality. The image quality was rated using the ratio of the visualized border divided by the total endocardial border. These ratings were used to generate groups of poor (0%-40%), fair (41%-70%), and good (71%-100%) image quality. The ejection fraction (EF), end-diastolic volume, and end-systolic volume were analyzed by the Simpson method of disks (biplane and monoplane), eyeball method, Teichholz method, and speckle-tracking method. Furthermore, the fractional area change was determined. Each correlation with real-time 3DE was evaluated. RESULTS: Correlations of the EF and volumes, respectively, as determined by long-axis view methods increased with improving image quality: the Simpson biplane method was found to be the most accurate method, with good image quality for the EF (r = 0.946) and volumes (end-diastolic volume, r = 0.962; end-systolic volume, r = 0.989). Correlations of the EF and fractional area change by short-axis view methods decreased with improving image quality, with the Teichholz EF found to be most accurate with poor (r = 0.928) in contrast to good (r = 0.699) image quality. CONCLUSIONS: With good image quality, the Simpson biplane method is the most accurate 2-dimensional method for assessing the left ventricular EF. Short-axis view methods, especially the Teichholz method yield better correlations with poor image quality. The eyeball method was unaffected by image quality.

Assessment of left ventricular size and function during cardiac surgery. An intraoperative evaluation of six two-dimensional echocardiographic methods with real time three-dimensional echocardiography as a reference.

Transesophageal echocardiography is recommended to monitor left ventricular (LV) size and function in various operations. Generally, two-dimensional (2D) methods are applied intraoperatively. The aim of this study was to compare the accuracy and feasibility of 6 commonly used 2D methods to assess LV function during surgery. LV function in 120 consecutive patients was evaluated. Real time three-dimensional transesophageal echocardiograpy (3DTEE) served as reference. End-diastolic and end-systolic volumes and ejection fraction (EF) were analyzed with Simpson's method of discs (monoplane [MP] and biplane [BP]), eyeball method, Teichholz' method, and speckle tracking (ST) methods. Furthermore, fractional area change (FAC) and peak systolic pressure rise (dP/dt) were determined. Each 2D method was evaluated regarding correlation and agreement with 3DE, intra- and interobserver variability and the time required for evaluation. Simpson BP showed the strongest correlation and best agreement with 3DE for EF (limits of agreement 3.7 ± 11.6%) and volumes. Simpson MP showed similar agreement with 3DE compared to ST (2.8 ± 14.5% vs. 2.0 ± 15.3% and 3.8 ± 14.4% vs. 1.9 ± 15.6%, respectively). Both the eyeball method and Teichholz' method showed wide limits of agreement (-1.5 ± 18.2% and 5.2 ± 22.1%, respectively). DP/dt did not correlate with 3DE. FAC and ST FAC showed similar agreement. Application of 3DE (429 ± 108 seconds) took the longest time, and the eyeball method took the shortest time (8 ± 5 seconds) for analysis. Simpson BP is the most accurate intraoperative 2D method to evaluate LV function, followed by long-axis MP evaluations. Short-axis views were less accurate but may be suited for monitoring. We do not recommend using dP/dt.

Comparison of intraoperative three-dimensional Doppler color flow mapping to assess mitral regurgitation.

BACKGROUND: Three-dimensional (3D) transesophageal echocardiography (TEE) enables the determination of the vena contracta area (VCA), which is an approved parameter to quantify mitral regurgitation (MR). The aim of this study was to determine the VCA in the operative setting and to compare it to alternative 3D and standard 2D methods, with respect to different etiologies of MR. METHODS: MR in 56 consecutive patients undergoing cardiac surgery was evaluated using 2D and 3D TEE. VCA, vena contracta (VC), and effective regurgitation orifice area (EROA) by 3D and 2D flow convergence methods were determined. The correlations among the methods and the determined areas were evaluated. RESULTS: EROA determination using 3D flow convergence areas correlated strongly with VCA (r = 0.653), however the resulting areas were considerably smaller. VC measurements in the 3D data set correlated slightly less (r = 0.629). EROA, which was determined using 2D flow convergence areas, showed the strongest correlation among the 2D methods (r = 0.406). 2D VC measurements showed weak to no correlation with VCA. Although a correlation was detected when using the biplane method or the midesophageal long-axis view to measure VC, statistical significance was only reached in functional MR and MR due to simple prolapse. CONCLUSIONS: Intraoperative 3D methods to determine MR were feasible and showed improved correlation with VCA compared to 2D measurements. The agreement of 2D methods with VCA declined from functional MR to MR due to prolapse. We recommend the utilization of 3D color Doppler for intraoperative evaluation of MR, especially in patients with complex mitral valve prolapses.

Experts and beginners benefit from three-dimensional echocardiography: a multicenter study on the assessment of mitral valve prolapse.

BACKGROUND: Three-dimensional (3D) transesophageal echocardiography (TEE) has been claimed to provide more information than two-dimensional (2D) TEE in the localization of mitral valve prolapse (MVP). However, most studies have been performed by experts in echocardiography, without accounting for differences in training or expertise. This multicenter study was designed to assess the differences between experts and inexperienced echocardiographers in localizing MVP and ruptured chordae tendineae using 2D and real-time 3D TEE. METHODS: Thirty-six observers from 10 institutions in Germany and Switzerland interpreted 2D and 3D transesophageal echocardiographic images from six patients selected to represent a large spectrum of MVP diversity. Surgical findings served as a reference. Individual performance in the prediction of pathology was scored. Differences between 15 experts and 21 beginners in TEE were assessed, and the benefits conferred by 3D TEE were compared. RESULTS: Both study groups scored significantly higher when interpreting 3D transesophageal echocardiographic images (P ≤ .001). The experts were superior in 2D MVP localization (14.8%; P ≤ .001), a difference that diminished with 3D TEE (1.4%; P = .41). The benefit of access to 3D information for MVP localization was greater for inexperienced echocardiographers compared with experts (P < .001). CONCLUSIONS: The reported diagnostic advantage of 3D TEE over 2D TEE in MVP assessment for expert echocardiographers can be transferred to inexperienced echocardiographers. Inexperienced echocardiographers benefit from the technology to a greater extent than their expert colleagues.