Murine Fetal Echocardiography

Transgenic mice displaying abnormalities in cardiac development and function represent a powerful tool for the understanding the molecular mechanisms underlying both normal cardiovascular function and the pathophysiological basis of human cardiovascular disease. Fetal and perinatal death is a common feature when studying genetic alterations affecting cardiac development ^1-3. In order to study the role of genetic or pharmacologic alterations in the early development of cardiac function, ultrasound imaging of the live fetus has become an important tool for early recognition of abnormalities and longitudinal follow-up. Noninvasive ultrasound imaging is an ideal method for detecting and studying congenital malformations and the impact on cardiac function prior to death ⁴. It allows early recognition of abnormalities in the living fetus and the progression of disease can be followed in utero with longitudinal studies ^5,6. Until recently, imaging of fetal mouse hearts frequently involved invasive methods. The fetus had to be sacrificed to perform magnetic resonance microscopy and electron microscopy or surgically delivered for transillumination microscopy. An application of high-frequency probes with conventional 2-D and pulsed-wave Doppler imaging has been shown to provide measurements of cardiac contraction and heart rates during embryonic development with databases of normal developmental changes now available ^6-10. M-mode imaging further provides important functional data, although, the proper imaging planes are often difficult to obtain. High-frequency ultrasound imaging of the fetus has improved 2-D resolution and can provide excellent information on the early development of cardiac structures ¹¹.     

Transthoracic Echocardiography in Mice

In recent years, murine models have become the primary avenue for studying the molecular mechanisms of cardiac dysfunction resulting from changes in gene expression. Transgenic and gene targeting methods can be used to generate mice with altered cardiac size and function,^1-3 and as a result, in vivo techniques are needed to evaluate their cardiac phenotype. Transthoracic echocardiography, pulse wave Doppler (PWD), and tissue Doppler imaging (TDI) can be used to provide dimensional measurements of the mouse heart and to quantify the degree of cardiac systolic and diastolic performance. Two-dimensional imaging is used to detect abnormal anatomy or movements of the left ventricle, whereas M-mode echo is used for quantification of cardiac dimensions and contractility.^4,5 In addition, PWD is used to quantify localized velocity of turbulent flow,⁶ whereas TDI is used to measure the velocity of myocardial motion.⁷ Thus, transthoracic echocardiography offers a comprehensive method for the noninvasive evaluation of cardiac function in mice.     

Echocardiography in the diagnosis left ventricular noncompaction

We describe a case of severe congestive heart failure and right ventricular overload associated with overt hyperthyroidism, completely reversed with antithyroid therapy in a few week. It represents a very unusual presentation of overt hyperthyroidism because of the severity of right heart failure. The impressive right ventricular volume overload made mandatory to perform transesophageal echo and angio-TC examination to exclude the coexistence of ASD or anomalous pulmonary venous return. Only a few cases of reversible right heart failure, with or without pulmonary hypertension, have been reported worldwide. In our case the most striking feature has been the normalization of the cardiovascular findings after six weeks of tiamazole therapy.     

Echocardiography: a new window for the heart

A satellite symposium was organised and sponsored by Philips Medical System with the purpose of presenting the novel echocardiographic techniques and exploring their possible clinical applications. This session was chaired by P. Hanrath (Aachen, Germany) and R.M. Lang (Chicago, US).     

超声心动图检测胎儿心包积液的临床价值

目的：探讨超声心动图检测胎儿心包积液的临床意义。方法：2007-2010年在我院检查行超声心动图检查的高危孕妇473例,同时设对照组,检测孕龄在20-40周无明显高危妊娠因素的孕妇472例,并将产前超声检查结果和胎儿尸检或分娩后超声心动图检查结果进行对照。结果：1.高危组检出72例心包积液,检出率12.5%,对照组检出13例心包积液,检出率3%,两组胎儿心包积液检出率间差别有统计学意义（x2=39.57,P〈0.05）。2.85例心包积液中,孤立性心包积液38例,伴其他心脏畸形或者其他系统畸形47例,其中孤立性心包积液预后良好。结论：超声心动图能够敏感地检出胎儿心包积液;心包积液程度并不是最重要的,其伴随心脏畸形或者其他畸形决定预后。     

超声心动图对心肌致密化不全的诊断价值

目的:探讨超声心动图对心肌致密化不全(noncompaction of ventricularmyocardium,NVM)的诊断价值.方法:采用二维、M型及多普勒超声心动图对疑似NVM患者进行多切面扫查.结果:9例患者均为左室受累.超声心动图检查可见左室内多发杂乱的肌小梁和深陷的小梁间隙(即隐窝)交织成的"海绵"样网状结构,其中小梁间隙与心室腔相通,深陷的隐窝内血流与心室腔相交通.非致密化心肌层与致密化心肌层厚度之比大于2.结论:超声心动图是诊断NVM的重要手段,在无明显临床症状时即可诊断,具有特征性意义.     

Right Ventricular Function Quantification in Takotsubo Cardiomyopathy Using Two-Dimensional Strain Echocardiography

Aims

This study sought to characterize global and regional right ventricular (RV) myocardial function in patients with Takotsubo cardiomyopathy (TC) using 2D strain imaging.

Methods

We compared various parameters of RV and left ventricular (LV) systolic function between 2 groups of consecutive patients with TC at initial presentation and upon follow-up. Group 1 had RV involvement and group 2 did not have RV involvement.

Results

At initial presentation, RV peak systolic longitudinal strain (RVPSS) and RV fractional area change (RVFAC) were significantly lower in group 1 (−13.2±8.6% vs. −21.8±5.4%, p = 0.001; 30.7±9.3% vs. 43.5±6.3%, p = 0.001) and improved significantly upon follow-up. Tricuspid annular plane systolic excursion (TAPSE) did not differ significantly at initial presentation between both groups (14.8±4.1 mm vs. 17.9±3.5 mm, p = 0.050). Differences in regional systolic RV strain were only observed in the mid and apical segments. LV ejection fraction (LVEF) and LV global strain were significantly lower in group 1 (36±8% vs. 46±10%, p = 0.006 and −5.5±4.8% vs. −10.2±6.2%, p = 0.040) at initial presentation. None of the parameters were significantly different between the 2 groups upon follow-up. A RVPSS cut-off value of >−19.1% had a sensitivity of 85% and a specificity of 71% to discriminate between the 2 groups.

Conclusion

In TC, RVFAC, RVPSS, LVEF and LV global strain differed significantly between patients with and without RV dysfunction, whereas TAPSE did not. 2 D strain imaging was feasible for the assessment of RV dysfunction in TC and could discriminate between patients with and without RV involvement in a clinically meaningful way.