| Backgrounds:The interventional therapy of the congenital heart diseases has developed greatly in the recent years. It is the trend that the interventional occlusion will be the first choice in the therapy of atrial septal defect (ASD) and ventricular septal defect (VSD). The general comprehension of the cardiac structure will directly affect the results and the prognosis of the interventional therapy. In the patient's selection before operation, the guiding and monitoring during operation and the assessment of the implant's function after operation, echocardiography occupies an irreplaceable position. The transthoracic and transesophegeal two-dimensional echocardiography can reveal the cardiac structure; however, because of the restriction of sound window and the planar characteristic of the two-dimensional plane, it can not show the shape of the septal defect and how it adjoins the surrounding tissue generally and with three-dimensional effect, which affects the determination of operation indications, the selection of occluders' types and the results of the occlusions. Recently three-dimensional echocardiography (3DE) developed rapidly with the advancement of computer technology. Many researches have exposed that 3DE can disclose the intra-cardiac structure's shape, size, direction its relative position with the neighboring tissue and the relation between the heart and the large blood vessels; what's more, it can also display the structure's motion in one cardiac-cycle. But there is still scarcely any report on the value of 3DE when it was used in the interventional therapy adopting the Amplatzer occluder.Objectives:?By researching the cardiac specimen in vitro, we want to establish the methods for reconstructing the 3-D imaging and found the reasonable optimized scheme for 3-DE examination, by which to improve the efficiency of 3-D reconstruction and provide methodological evidence for 3-DE. (2) To evaluate the feasibility and accuracy of 3-DE in the measuring of left ventricular volume. (3) To assess the feasibility and accuracy of 3-D reconstruction of target cardiac structures in patients with congenital heart diseases and the application value of 2DE and 3DE in the interventional therapy adopting the Amplatzer occluder.Methods:1. We use the Sonos5500 ultrasound diagnosis system with 3-DE sampling software (Philips Co.Ltd, Holand) and the multiplane transthoracic probe (Transthoracic omniplane TTO) to collect 2-D images of the human or swine hearts in vitro. Then we use the software Echoview 4.2 in the Tomtac workstation to made 3-D reconstruction from the original images and got the dissection ,comprehension and the manifestation of those 3-D images. By applying the optional incise function of the software, we could get the 3-D dissected view of the interested cardiac areas to reveal the 3-D shape of target structures, which were compared with the specimen.2. Five factors: sampling angle interval, gain, compress, gray scalethreshold and opacity of images which have great effect on the 3D reconstruction and need adjustment or setting by hand were choosed as factors for direct-cross design. Each factor has four levels. According the L1635 direct-cross table, we use the Direct-Cross Design Assistant II (V3.0 version) to design our testing plan table. Using the main-effect-analysis method of the direct-cross test designand taking the display efficiency of 3-D reconstruction as the main effect, we choose the scheme that could achieve the best information collection and 3-D reconstruction in the shortest time.3. We used 3-DE to reconstruct the left ventricle chambers of human and swine hearts in vitro and made the plaster cast of them, then we compared the 3-D imaging with the plaster cast. We also use 2-DE, 3-DE and the plaster cast to measure the left ventricle volume respectively and analyzed their correlation.4. To the patients who would underwent Amplatzer ASD occlusion and whose secundum ASD had been successfully reconstructed by 3-DE, we measured the size of... |
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