Three Dimensional Reconstruction of Transesophageal Echocardiographic Longitudinal Images

3D Echocardiography for Rheumatic Heart Disease Analysis: Ready for Prime Time

Rheumatic heart disease (RHD) remains to be a very important health issue worldwide, mainly in underdeveloped countries. It continues to be a leading cause of morbidity and mortality throughout developing countries. RHD is a delayed non-suppurative immunologically mediated inflammatory response to the throat infection caused by a hemolytic streptococcus from the A group (Streptococcus pyogenes). RHD keeps position 1 as the most common cardiovascular disease in young people aged <25 years considering all the continents. The disease can lead to valvular cardiac lesions as well as to carditis. Rheumatic fever valvular injuries lead most commonly to the fusion and thickening of the edges of the cusps and to the fusion, thickening, and shortening of the chordae and ultimately to calcification of the valves. Valvular commissures can also be deeply compromised, leading to severe stenosis. Atrial and ventricular remodeling is also common following rheumatic infection. Mixed valvular lesions are more common than isolated valvular disorders. Echocardiography is the most relevant imaging technique not only to provide diagnostic information but also to enable prognostic data. Further, it presents a very important role for the correction of complications after surgical repair of rheumatic heart valvulopathies. Three-dimensional (3D) echocardiography provides additional anatomical and morphofunctional information of utmost importance for patients presenting rheumatic valvopathies. Accordingly, three-dimensional echocardiography is ready for routine use in patients with RHD presenting with valvular abnormalities.

Three-Dimensional Echocardiographic Assessment of Aortic Dissection

In the present study, we report our experience of using three-dimensional reconstruction of transesophageal two-dimensional echocardiographic images in the assessment of aortic dissection (22 patients), aortic rupture (1 patient), aortic aneurysm without dissection (2 patients), and aortic tumor (1 patient).

Dynamic Three-Dimensional Reconstruction of Abnormal Intracardiac Blood Flow

Dynamic three-dimensional (3-D) echocardiography has so far focused on reconstruction of cardiac structures. In this preliminary study, abnormal intracardiac blood flow has been reconstructed in 3-D from multiplane transesophageal and transthoracic two-dimensional (2-D) echocardiograms using modified omniplane probes with 3.7- or 5.0-MHz transducers. The study group included patients with native (40) and prosthetic (11) mitral regurgitant jets, aortic regurgitant jets (8), and shunt flow in atrial septal defect (20), ventricular septal defect (19), tetralogy of Fallot (14), and ruptured sinus of Valsalva aneurysm (6). For dynamic 3-D intracardiac flow imaging the gain of 2-D images of cardiac structures was lowered slightly and color Doppler flow signals were transformed into gray scale flow signals, which were then collected in the TomTec 3-D Echo Scan System. Dynamic 3-D cardiac flow images were displayed with volume rendering. The results indicated that dynamic 3-D cardiac flow imaging facilitates display of the stereo shape, spatial orientation, profiles and volume of regurgitant jets, and the intracardiac shunting blood flow. It allows differentiation of prosthetic transvalvular from paravalvular regurgitant jets. Limitations include nonvelocity and nonECG synchronized display.

Four-dimensional echocardiography: methods and clinical application

4DE (i.e., dynamic three-dimensional) echocardiography is a new developing technique in recent years. In our study, a three-dimensional echo scan computer system was used to acquire and store the two-dimensional information, then to reconstruct the stereoscopic image of the heart according to its space-time continuum. It can yield a better approach, which can help identify the various structures of the heart and great arteries and facilitate understanding of spatial relations and motion. In addition, it can display physiologic information such as the direction, course, size, and shape of the blood flow. We have examined 138 patients by both transthoracic and transesophageal approaches. Our preliminary experience shows that 4DE is of great value in diagnosing congenital heart disease and valvular disease.