743-5 Evaluation of the Accuracy of New Quantitative Image Processing Methods in Measuring the Size of Ventricular Septal Defects Directly on Three-dimensional Echocardiograms and Factors Influencing its Reliability

Volume-rendered 3-D echocardiography(3DE) can display the shape and size of various ventricular septal defects (VSD). Quantitation of VSD size directly from 3DE images has not been possible and measurements (M) could be performed only in 2DE slices derived from 3DE and required tedious efforts to obtain the correct 2DE slice orientation, Newly developed image processing (IP) algorithms permitdirect M on 3DE imagesbut the reliability of this method in sizing VSDs is unclear, Also, the effects of operator-dependent IP factors such as thresholding (TH) and opacification (OP) on quantitation are unknown. In this study, we examined the accuracy ofdirect 3DE quantificationof VSDs and the influence of TH and OP. We created 17 VSDs of various types and shapes in 9 pig hearts and acquired 2-D images with a transducer mounted on a parallel scanning device (216 image slices over 60mm distance). 3DE reconstructions were accomplished anden-face viewsof the VSDs were derived. Using the new quantitation tool, we measured the maximum and minimum diameters (Max D and Min D), directly on the 3DE image under optimal IP settings and compared them to independent direct M from the anatomic specimens. M were also performed with changes in TH and OP.ResultsThe VSD site, shape and size on 3DE corresponded well with anatomic specimens. Max D (Mean±SD) by anatomy was 10±4mm (range 4–16), and by 3DE was 10±4 (range 4–15); Min D by anatomy was 9±3 mm (range 4–15). and by 3DE was 8 ± 4 (range 5-19). The correlations between 3DE (y) and anatomy were: Max D: y=1.0x + 0.3, r = 0.88, P<0.001; Min D: y = 1.0x – 1.4, r = 0.89, P<0.001. Increased TH by 10 units led to overestimation of the VSD size by 6±18%, while TH decrease by 10 units resulted in 8±13% under-estimation. Increased OP by 10 and 20 units led to overestimation of VSD size by 11±29% and 17±23%.Conclusion3DE provides unique en-face views of VSDs unavailable by 2DE. VSD size can be measured directly on the 3D image. Inappropriate processing steps can result in unreliable data, however with optimal processing VSDs can be quantified accurately

Real-Time 3-Dimensional Transesophageal Echocardiography in the Evaluation of Post-Operative Mitral Annuloplasty Ring and Prosthetic Valve Dehiscence

ObjectivesThis study sought to assess the use of real-time (RT) 3-dimensional (3D) transthoracic and transesophageal echocardiography (TEE) in the evaluation of post-operative mitral valve dehiscence.BackgroundMitral valve replacement or repair may be complicated by post-operative dehiscence of the valve or annuloplasty ring resulting in clinically significant mitral regurgitation or hemolysis. Diagnosis is generally performed using 2-dimensional transthoracic echocardiography and TEE. Recently, an RT 3D TEE probe has been developed to produce high-quality real-time images.MethodsWe used RT 3D TEE to evaluate mitral regurgitation after mitral valve repair or replacement as a result of mitral ring dehiscence. We studied the additional information and diagnostic utility provided by RT 3D TEE.ResultsEighteen patients were studied (8 patients after repair and 10 after replacement). Real-time 3D TEE allowed accurate evaluation of the pathology, including definition of the type of ring or prosthesis used; description of the site, size, shape, and area of the dehisced segment; and clear definition of the origin of the mitral regurgitation.ConclusionsIn mitral valve dehiscence, RT 3D TEE provides additional information about the exact anatomic characteristics of the dehiscence that can be used to help in planning the most appropriate corrective intervention

Live 3-Dimensional Transesophageal Echocardiography Initial Experience Using the Fully-Sampled Matrix Array Probe

ObjectivesOur study goals were to evaluate the 3-dimensional matrix array transesophageal echocardiographic (3D-MTEE) probe by assessing the image quality of native valves and other intracardiac structures.BackgroundBecause 3-dimensional transesophageal echocardiography with gated rotational acquisition is not used routinely as the result of artifacts, lengthy acquisition, and processing, a 3D-MTEE probe was developed (Philips Medical Systems, Andover, Massachusetts).MethodsIn 211 patients, 3D-MTEE zoom images of the mitral valve (MV), aortic valve, tricuspid valve, interatrial septum, and left atrial appendage were obtained, followed by a left ventricular wide-angled acquisition. Images were reviewed and graded off-line (Xcelera with QLAB software, Philips Medical Systems).ResultsExcellent visualization of the MV (85% to 91% for all scallops of both MV leaflets), interatrial septum (84%), left atrial appendage (86%), and left ventricle (77%) was observed. Native aortic and tricuspid valves were optimally visualized only in 18% and 11% of patients, respectively.ConclusionsThe use of 3D-MTEE imaging, which is feasible in most patients, provides superb imaging of native MVs, which makes this modality an excellent choice for MV surgical planning and guidance of percutaneous interventions. Optimal aortic and tricuspid valve imaging will depend on further technological developments. Fast acquisition and immediate online display will facilitate wider acceptance and routine use in clinical practice

Systolic characteristics and dynamic changes of the mitral valve in different grades of ischemic mitral regurgitation - insights from 3D transesophageal echocardiography

Background: Mitral regurgitation in ischemic heart disease (IMR) is a strong predictor of outcome but until now, pathophysiology is not sufficiently understood and treatment is not satisfying. We aimed to systematically evaluate structural and functional mitral valve leaflet and annular characteristics in patients with IMR to determine the differences in geometric and dynamic changes of the MV between significant and mild IMR. Methods: Thirty-seven patients with IMR (18 mild (m)MR, 19 significant (moderate+severe) (s)MR) and 33 controls underwent TEE. 3D volumes were analyzed using 3D feature-tracking software. Results: All IMR patients showed a loss of mitral annular motility and non-planarity, whereas mitral annulus dilation and leaflet enlargement occurred in sMR only. Active-posterior-leaflet-area decreased in early systole in all three groups accompanied by an increase in active-anterior-leaflet-area in early systole in controls and mMR but only in late systole in sMR. Conclusions: In addition to a significant enlargement and loss in motility of the MV annulus, patients with significant IMR showed a spatio-temporal alteration of the mitral valve coaptation line due to a delayed increase in active-anterior-leaflet-area. This abnormality is likely to contribute to IMR severity and is worth the evaluation of becoming a parameter for clinical decision-making. Further, addressing the leaflets aiming to increase the active leaflet-area is a promising therapeutic approach for significant IMR. Additional studies with a larger sample size and post-operative assessment are warranted to further validate our findings and help understand the dynamics of the mitral valve