Evaluation of mitral valve prolapse using newly developed real-time three-dimensional echocardiographic system with real-time volume rendering.

The development of a real-time three-dimensional (RT3D) image acquisition system and direct digital links between ultrasound equipment and the data processing computer facilitate improved 3D image reconstruction. However, at present time, it is hard to promptly display 3D images and is also ineffective for a practical use. The objective of this study was to assess the feasibility of a new transthoracic RT3D echocardiographic system for evaluation of mitral valve prolapse. Eighteen patients with mitral valve prolapse diagnosed by transthoracic two-dimensional (2D) echocardiography and M-mode were examined through this technique (11 male, mean age 42 +/- 17 years). Since visualization of mitral valve from apical four-chamber view was better than that of the parasternal approach, only apical approach was used for mitral valve evaluation. This system is capable of acquiring volumetric data from mechanical scanning of the phased-array transducer (3.5 MHz) as well as displaying the volume rendered images of the structure without storing the image data and reconstruction of the object. The prolapse of leaflet could be seen in 14/ 18 (77%) of patients with mitral valve prolapse based on conventional echocardiography. The newly developed transthoracic RT 3D ultrasound system without a reconstruction process seemed to be a useful noninvasive tool for diagnosis of mitral valve prolapse and detection of prolapsed leaflet or scallop, which is very important for deciding on a reliable surgical technique.