Role of live/real time three-dimensional transesophageal echocardiography in the percutaneous epicardial closure of the left atrial appendage.

We are reporting the use of three-dimensional transesophageal echocardiography as a supplement to two-dimensional transesophageal echocardiography in the percutaneous suture closure of the left atrial appendage.

Transesophageal echocardiographic detection of thrombus superimposed on metastatic left atrial tumor.

We present a 32-year-old male with metastatic thymic carcinoma invading the left atrium in whom two-dimensional transesophageal echocardiography was able to differentiate a thrombus superimposed on the tumor.

Continuing medical education program in echocardiography.

Article Title: Association between Left Atrium Enlargement and Intradialytic Hypotension: Role of Diastolic Dysfunction in the Hemodynamic Complications during Hemodialysis.

Live/real time three-dimensional transthoracic echocardiographic assessment of tricuspid valve pathology: incremental value over the two-dimensional technique.

Twenty-nine patients with different tricuspid valve (TV) pathologies were studied by both two-dimensional transthoracic (2DTTE) and live/real time three-dimensional transthoracic echocardiography (3DTTE). A major contribution of 3DTTE over 2DTTE was the en face visualization of all three leaflets of the TV in all patients. This allowed accurate assessment of TV orifice area in patients with TV stenosis and carcinoid disease. Loss of TV leaflet tissue, defects in TV leaflets and size of TV systolic non-coaptation could also be delineated and resulted in identifying the mechanism of tricuspid regurgitation (TR) in patients with Ebstein's anomaly and rheumatic heart disease. Prolapse of TV leaflets could also be well visualized and enabled us to develop a schema for systematic assessment of individual segment prolapse which could help in surgical planning. The exact sites of chordae rupture in patients with flail TV as well as right ventricular papillary muscle rupture could be well seen by 3DTTE. 3DTTE also permitted sectioning of various TV masses for more specific diagnosis of their nature. In addition, color Doppler 3DTTE provided an estimate of quantitative evaluation of TR severity, since the exact shape and size of the vena contracta could be accurately assessed. In conclusion, our preliminary experience with 3DTTE has demonstrated substantial incremental value over 2DTTE in the assessment of various TV pathologies.

Usefulness of live/real time three-dimensional transthoracic echocardiography in the identification of individual segment/scallop prolapse of the mitral valve.

In this report, we present 34 patients in whom surgical intervention was undertaken for severe mitral insufficiency due to mitral valve prolapse (MVP). Location and severity of MVP and regurgitation were assessed preoperatively by live/real time three-dimensional transthoracic echocardiography and closely agreed with the surgical findings.

Infected cardiac myxoma.

Infected cardiac myxomas are extremely rare with only forty cases described in the literature. We report a case of an infected cardiac myxoma that presented in a manner similar to bacterial endocarditis. Our case is the first to be diagnosed using previously defined criteria, and is unusual in that transesophageal echocardiography was required to make the diagnosis.

Analysis of the Proximal Orifice Flowfield Under Pulsatile Flow Conditions and Confining Wall Geometry: Implications in Valvular Regurgitation.

Hemodynamic studies of regurgitant lesions in the heart focus on identifying a reliable noninvasive method of volumetric flow calculation. In these studies the influence of blood viscosity to the flowfield under pulsatile flow conditions and constraining wall geometry has not been examined in detail. Pulsatile flow studies in straight tubes have shown that viscous effects significantly influence the periodic flowfield, especially near the wall. The purpose of this study is to investigate the significance of transient effects in the flowfield proximal to a lesion under constraining wall geometry. The proximal flowfield was analyzed with computational fluid dynamics (CFD) computer simulations and color flow Doppler mapping (CFM). Three different stroke volumes and regurgitant waveforms were investigated for upstream wall orientations that varied from -64 degrees to +64 degrees (measured from the orifice plane). Results showed that for each upstream wall orientation, a single instantaneously normalized centerline velocity distribution characterized the flowfield throughout the cycle. The centerline distributions were in phase with the pressure gradient and almost identical to the corresponding steady-state distributions. Minor deviations were observed near the wall, where viscous effects were predominant. Transient flow effects such as blunt profiles and pressure velocity phase shifts, which were observed in straight circular tubes, were not observed in regurgitant orifice flowfields. This is true even under severe confinement conditions.