Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques 

About: Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques is an academic journal published by Wiley. The journal publishes majorly in the area(s): Ejection fraction & Diastole. It has an ISSN identifier of 0742-2822. Over the lifetime, 6641 publications have been published receiving 70953 citations.

Two-dimensional assessment of right ventricular function: an echocardiographic-MRI correlative study.

Abstract: Background: While echocardiography is used most frequently to assess right ventricular (RV) function in clinical practice, echocardiography is limited in its ability to provide an accurate measure of RV ejection fraction (RVEF). Hence, quantitative estimation of RV function has proven difficult in clinical practice. Objective: We sought to determine which commonly used echocardiographic measures of RV function were most accurate in comparison with an MRI-derived estimate of RVEF. Methods: We analyzed RV function in 36 patients who had cardiac MRI studies and echocardiograms within a 24 hour period. 2D parameters of RV function—right ventricular fractional area change (RVFAC), tricuspid annular motion (TAM), and transverse fractional shortening (TFS) were obtained from the four-chamber view. RV volumes and EFs were derived from volumetric reconstruction based on endocardial tracing of the RV chamber from the short axis images. Echocardiographic assessment of RV function was correlated with MRI findings. Results: RVFAC measured by echocardiography correlated best with MRI-derived RVEF (r = 0.80, P < 0.001). Neither TAM (r = 0.17; P = 0.30) nor TFC (r = 0.12; p< 0.38) were significantly correlated with RVEF. Conclusions: RVFAC is the best of commonly utilized echocardiographic 2D measure of RV function and correlated best with MRI-derived RV ejection fraction. Condensed Abstract: While echocardiography is used most frequently to assess RV function in clinical practice, echocardiography is limited in its ability to provide an accurate measure of RV ejection fraction (RVEF). Using cardiac MRI, RV fractional area change (RVFAC), determined either by MRI or echocardiography, was found to correlate best with MRI-derived RVEF.

Basic acoustic properties of microbubbles.

Abstract: Small (encapsulated) gas bubbles in a contrast medium react to an external oscillating pressure field with volume pulsations. Depending on the magnitude of the ultrasound wave, the vibrations will be related either linearly or nonlinearly to the applied acoustic pressure. For low acoustic pressures, the instantaneous radius oscillates linearly in relation to the amplitude of the applied external pressure field. The oscillation of the bubble is governed by parameters such as resonance frequency, damping coefficients, and shell properties. For higher amplitudes of the external field, the pulsation of the bubbles becomes nonlinear. The spectrum of the scattered ultrasound wave also contains higher harmonics of the emitted frequency in addition to the fundamental frequency. The emitted frequency, bubble size, and nonlinear propagation effects have significant influence on the harmonic generation. For encapsulated bubbles exposed to even higher acoustic amplitudes, their scattering effectiveness increases dramatically and becomes transient. The scattered frequency spectrum broadens, containing higher harmonics. This consequence is due to rupture, disappearance, change of gas content, etc. Using these specific characteristics of the contrast bubbles will open new perspectives in imaging and analysis for medical diagnosis.

The Natural History of Left Ventricular Filling Abnormalities: Assessment by Two‐Dimensional and Doppler Echocardiography

Abstract: Doppler and two-dimensional echocardiography are being increasingly used for the indirect assessment of left ventricular (LV) diastolic function. In this article the alterations in LV filling patterns that occur in patients with LV diastolic function are reviewed in the context of echocardiographic findings. A progression of LV filling abnormalities is presented in the sequential “stages” in which we believe they occur in most cardiac disease states. Patient symptoms, hemodynamics, pulmonary venous flow velocities, and left atrial function associated with the different LV filling patterns are also discussed.

Characteristics of SonoVue

Abstract: The advances made by ultrasonography in the last decade, in parallel with the development of ultrasound contrast agents, have opened a wide range of potential breakthroughs in the field of ultrasound imaging. SonoVue(trade mark) is a new echocontrast agent made of microbubbles stabilized by phospholipids and containing sulphur hexafluoride (SF6), an innocuous gas. The suspension of the microbubbles is stable over the time following reconstitution. The bubble concentration of SonoVue(trade mark) is between 100 and 500 million per ml. The mean bubble diameter is 2.5 µm and more than 90% of the bubbles are smaller than 8 µm. Following intravenous injection, the bubble suspension is submitted to pressure increases. SF(6), a high molecular weight gas with low solubility in water, was selected since laboratory tests showed that it confers to the bubbles a good resistance to pressure changes as those that occur in the left ventricle, in the pulmonary capillaries, or in the coronary circulation. The high bubble concentration, combined with a favorable size distribution profile, provides SonoVue(trade mark) with a strong echogenicity. SonoVue(trade mark) shows a peak in the backscatter coefficient at about 3 MHz. With regard to the gas contained in the bubbles, its pharmacokinetics have been assessed during a study in human volunteers. Following intravenous administration of 0.3 ml/kg of SonoVue(trade mark) (i.e., approximately ten times the imaging dose), the blood level curve showed a distribution half-life of about 1 minute and an elimination half-life of about 6 minutes. More than 80% of the administered gas is exhaled via the lungs after 11 minutes. Extensive studies in animals and humans have confirmed the outstanding safety profile of this second generation contrast agent and its capability in providing a clinically useful ultrasound signal enhancement for the evaluation of cardiac function and extracardiac vessel abnormalities. Thanks to the long persistence of SF(6) microbubbles, SonoVue(trade mark) is also potentially useful in the assessment of myocardial perfusion, as well as microcirculatory disorders.

Left ventricular ejection fraction and volumes: it depends on the imaging method.

Abstract: Background and Methods In order to provide guidance for using measurements of left ventricular (LV) volume and ejection fraction (LVEF) from different echocardiographic methods a PubMed review was performed on studies that reported reference values in normal populations for two-dimensional (2D ECHO) and three-dimensional (3D ECHO) echocardiography, nuclear imaging, cardiac computed tomography, and cardiac magnetic resonance imaging (CMR). In addition all studies (2 multicenter, 16 single center) were reviewed, which included at least 30 patients, and the results compared of noncontrast and contrast 2D ECHO, and 3D ECHO with those of CMR. Results The lower limits for normal LVEF and the normal ranges for end-diastolic (EDV) and end-systolic (ESV) volumes were different in each method. Only minor differences in LVEF were found in studies comparing CMR and 2D contrast echocardiography or noncontrast 3D echocardiography. However, EDV and ESV measured with all echocardiographic methods were smaller and showed greater variability than those derived from CMR. Regarding agreement with CMR and reproducibility, all studies showed superiority of contrast 2D ECHO over noncontrast 2D ECHO and 3D ECHO over 2D ECHO. No final judgment can be made about the comparison between contrast 2D ECHO and noncontrast or contrast 3D ECHO. Conclusion Contrast 2D ECHO and noncontrast 3D ECHO show good reproducibility and good agreement with CMR measurements of LVEF. The agreement of volumes is worse. Further studies are required to assess the clinical value of contrast 3D ECHO as noncontrast 3D ECHO is only reliable in patients with good acoustic windows.