Rongjuan Li

Speckle tracking echocardiography in the diagnosis of early left ventricular systolic dysfunction in type II diabetic mice

AbstractsBackgroundThe leptin receptor-deficient db/db mouse is a well-established type II diabetes animal model used to investigate diabetic cardiomyopathy. Previous reports have documented diabetic cardiomyopathy is accompanied by cardiac structural and functional abnormalities. To better elucidate early or subtle changes in cardiac performance in db/db mice, we used speckle tracking echocardiography to assess systolic myocardial strain in vivo with diabetic db/db mice in order to study early changes of left ventricle contractile function in type II diabetes model.MethodsMale diabetic db/db mice and age-matched control mice from C57BL/6J strain at 8,12 and 16 weeks of age were subjected to echocardiography. At the midpapillary level in the parasternal left ventricular short-axis view, end diastolic and systolic left ventricular diameter, interventricular septal thickness and posterior wall thicknesses, ejection fraction, fractional shortening were determined by M-mode echocardiography. Using speckle-tracking based strain analysis of two-dimensional echocardiographic images acquired from the parasternal short-axis views at the mid-papillary level, systolic global radial and circumferential strain values were analyzed.ResultsThere was no significant difference in interventricular septal thickness, posterior wall thicknesses, end diastolic and systolic left ventricular diameter, ejection fraction and fractional shortening between db/db and age-matched control mice at 8,12 or 16 weeks of age (P > 0.05). At 8 and 12 weeks of age, there was no significant difference in left ventricular radial strain and circumferential strain between db/db mice and age-matched controls (P > 0.05). But at 16 weeks of age, the left ventricular radial strain and circumferential strain in db/db mice were lower than in control mice (P < 0.01).ConclusionThe present study shows that speckle tracking echocardiography can be used to evaluate cardiac functional alterations in mouse models of cardiovascular disease. Radial and circumferential strain are more sensitive and can be used for detection of early left ventricular contractile dysfunction in db/db type II diabetic mice.

Intravenous leiomyomatosis with intracardiac extension: echocardiographic study and literature review.

Uterine leiomyomatosis is a common disease in women; however, intravenous leiomyomatosis with intracaval and intracardiac tumor extension is rare. We sought to analyze the clinical and echocardiographic features of intracardiac leiomyomatosis. From January 2003 through July 2012, 7 women (age range, 24-59 yr) underwent surgical resection of histopathologically diagnosed intracardiac leiomyomas at our hospital. Most of the patients had histories of hysterectomy or uterine leiomyoma. We retrospectively analyzed their preoperative echocardiograms. We found that the tumors had no stalks, did not adhere to the wall of the right side of the heart, were highly mobile, and moved back and forth in the right atrium near the tricuspid orifice. All tumors originated from the inferior vena cava and had borders well demarcated from that structures wall. Most of the masses extended into the inferior vena cava and right atrium through the right internal and common iliac veins. Computed tomograms revealed pelvic tumors and contiguous filling defects in 6 patients. When echocardiograms reveal a right-sided cardiac mass that originates from the inferior vena cava, particularly in women who have a history of hysterectomy or uterine leiomyoma, intracardiac leiomyomatosis should be suspected. If the mass has no stalk and freely moves within the inferior vena cava and right-sided cardiac chambers without attachment to the endothelial surface or endocardium, intracardiac leiomyomatosis should be diagnosed. We discuss our findings and briefly review the relevant medical literature.

Early Detection of Regional and Global Left Ventricular Myocardial Function Using Strain and Strain-rate Imaging in Patients with Metabolic Syndrome

Background: Strain and strain-rate imaging (SRI) have been found clinically useful in the assessment of cardiac systolic and diastolic function as well as providing new insights in deciphering cardiac physiology and mechanics in cardiomyopathies, and identifying early subclinical changes in various pathologies. The aim of this study was to evaluate the regional and global left ventricular (LV) myocardial function in metabolic syndrome (MS) with SRI so that we can provide more myocardial small lesions in patients with MS, which is robust and reliable basis for early detection of LV function. Methods: Thirty-nine adults with MS were enrolled in the study. There was a control group of 39 healthy adults. In addition to classic echocardiographic assessment of LV global functional changes, SRI was used to evaluate regional and global LV function. Including: Peak systolic strain (S), peak systolic strain-rate (SR-s), peak diastolic strain-rate (SR-e). Results: There were no statistically significant differences between MS and controls in all traditional parameters of LV systolic function. On the other hand, significant differences were observed between MS and the control group in most of the parameters of S, SR-s, SR-e in regional LV function. Multiple stepwise regression analyses revealed that S and SR significantly were negatively correlated with blood pressure, waist circumference, fasting plasma glucose, uric acid, suggesting that risk factories were relevant to regional systolic dysfunction. Conclusion: In MS with normal LV ejection fraction, there was regional myocardial dysfunction, risk factors contributed to the impairment of systolic and diastolic function of the regional myocardium. Assessment of myocardial function using SRI could be more accurate in MS patient evaluation than conventional echocardiography alone.

Layer-specific myocardial strain analysis: investigation of regional deformation in a rabbit model of diabetes mellitus during different stages.

AIM The purpose of the present study was to determine the characteristics of myocardial damage at different stages of diabetes mellitus (DM) using layer-specific myocardial strain. MATERIAL AND METHODS Thirty six New Zealand white rabbits were randomly divided into either the control group (n =18) or the DM group (induced with alloxan) (n=18). For the myocardial deformation studies echocardiography and layer-specific strain were performed at baseline and after 3, 6, and 9 months in all of the rabbits. Three-layer longitudinal strain (LS) was calculated in the apical 4-chamber view, and three-layer circumferential strain (CS) in the short-axis view at the level of mitral valve. Layer-specific longitudinal and circumferential strains were assessed from endocardium, mid-myocardium and epicardium. For histomorphological study of the heart structure, the rabbits were sacrificed at 3, 6 and 9 months. Routine hematoxylin and eosin staining was performed. RESULTS The highest absolute values of left ventricular longitudinal strain (LS) and circumferential strain (CS) were registered in the endocardium and the lowest in the epicardium in both groups. At 3 months, there was no significant difference in three-layer LS and CS (p>0.05), but at 6 months the LS of endocardium (LSendo) and CS of endocardium (CSendo) were lower in the DM group compared with the control group; at 9 months, the rest of the parameters were also decreased (p<0.05). Moreover, in ROC analysis at 6 months LSendo yielded better sensitivity and specificity in the detection of diabetic cardiomyopathy (AUC of LSendo was 0.897 and AUC of CSendo was 0.617). With the progression of untreated diabetes, the histopathological abnormalities intensified gradually beginning at 6 months. CONCLUSION The progressive impairments in LV myocardial deformation and structure occurs early in diabetic rabbits, the myocardial damage may be nontransmural, and endocardial function is more susceptible to be affected by DM. Layer-specific myocardial strain echocardiography may identify subtle myocardial dysfunction in the early stages of DM.

EVALUATION OF CORONARY FLOW VELOCITY RESERVE IN HOMOZYGOUS FAMILIAL HYPERCHOLESTEROLEMIA BY TRANSTHORACIC DOPPLER ECHOCARDIOGRAPHY AND DUAL-SOURCE COMPUTED TOMOGRAPHY

Homozygous familial hypercholesterolemia (HoFH) is a rare disorder characterized by the early onset of atherosclerosis and usually occurs at the ostia of coronary arteries. In this study, we used transthoracic Doppler echocardiography (TTDE) to evaluate the dynamic changes of coronary flow in HoFH patients and to detect aortic and coronary atherosclerosis by dual-source computed tomography (DSCT). We studied 20 HoFH patients (12 females, 8 males, mean age 13.1 ± 5.3 years, with a mean low density lipoprotein (LDL) cholesterol of 583 ± 113 mg/dL) and 15 control patients (8 females, 7 males, mean age 15.2 ± 6.9 years, with a mean LDL cholesterol 128 ± 71 mg/dL) using TTDE and DSCT. None of the patients showed evidence of ischemia with standard exercise testing. Though the baseline coronary flow was similar between HoFH patients and normal controls, the hyperemic flow velocities and, thus, the coronary flow velocity reserve (CFVR) were significantly lower in those with HoFH. All HoFH patients had aortic plaques, nine of them with the coronary artery ostia simultaneously, who had significantly higher LDL-cholesterol and lower CFVR than those without ostia plaques. Our data demonstrated that TTDE together with DSCT could be a useful noninvasive method for detection of coronary flow dynamics and atherosclerosis specifically in HoFH subjects with coronary ostia.

Regional Atrial Myocardial Velocity in Normal Fetuses: Evaluation by Quantitative Tissue Velocity Imaging

Objectives: Quantitative tissue velocity imaging (QTVI) is a new noninvasive method that derives measurements of velocities directly from the myocardium. Data on atrial myocardial tissue velocities in normal fetuses have not been established. The objective of this study was to evaluate atrial myocardial velocity and the myocardial velocity gradient of normal fetuses by using QTVI. Methods: We measured motion velocities of the left and right atrial wall along the long axis in 50 normal fetuses aged 21–32 weeks gestation (mean, 25.3 ± 2.8 weeks). In all fetuses, peak myocardial velocity during early diastole (EW), atrial contraction (AW), and ventricular systole (SW) waves was recorded in the basal and mid‐atrial segments. Correlation analysis was conducted between segmental velocities of the left atrium (LA) and right atrium (RA) and gestational age. Results: The mean values for EW, AW, and SW of the long axis in the same right basal segment of the RA were greater than those of the LA (P < 0.01). There was a degressive gradient with velocity from the basal to superior in the atrial wall. There was a linear relationship with gestation for all basal myocardial velocities of the left and right atrial free wall (P < 0.05). However, the myocardial velocity variables of the midatrial wall showed no age‐dependence. Conclusion: We demonstrated that QTVI is reproducible and provides readily obtained parameters that provide unique data regarding segmental atrial myocardial velocity in normal fetuses. (Echocardiography 2012;29:182‐186)

Ultrasound Biomicroscopic Imaging for Interleukin-1 Receptor Antagonist-Inhibiting Atherosclerosis and Markers of Inflammation in Atherosclerotic Development in Apolipoprotein-E Knockout Mice.

We sought to validate the hypothesis that the development of atherosclerosis can be suppressed by the interleukin-1 receptor antagonist (IL-1Ra) in murine models of atherosclerosis in vivo, noninvasively seen by means of high-resolution ultrasound biomicroscopy, and we studied changes in inflammatory markers such as IL-1 and C-reactive protein (CRP) plasma levels in these models of atherosclerosis. We divided IL-1Ra(+/-)/apolipoprotein-E (apoE)(-/-) and IL-1Ra(+/+)/apoE(-/-) mice into 2 age groups, used as atherosclerotic models. The control groups were age-matched IL-1Ra(+/+)/apoE(+/+) mice. Plaque thickness was measured in the ascending aorta in short-axis images by means of ultrasound and histology. Plasma levels of IL-1 and CRP were quantified in the 3 murine groups. At 16 weeks, plaque thickness in the ascending aortas of the IL-1Ra(+/-)/apoE(-/-) mice was significantly greater than that in the IL-1Ra(+/+)/apoE(-/-) mice, on ultrasound and histology (P <0.01). In contrast, at 32 weeks, the differences between these 2 genotypes were not statistically significant. Serum IL-1 levels were lower in the IL-1Ra(+/-)/apoE(-/-) mice than in the IL-1Ra(+/+)/apoE(-/-) mice at 16 and 32 weeks (P <0.05). At 16 weeks, serum CRP levels in the IL-1Ra(+/-)/apoE(-/-) mice were higher than in the IL-1Ra(+/+)/apoE(-/-) mice (P <0.01). Our results suggest that ultrasound biomicroscopy enables evaluation of atherosclerotic lesions in vivo, noninvasively and in real-time, in apoE(-/-) mice. Partial IL-1Ra deficiencies might promote early plaque development in 16-week-old apoE(-/-) mice. The balance of IL-1 and IL-1Ra might influence atherosclerotic development. Finally, CRP might affect the initiation of atherosclerosis, rather than its progression.

Noninvasive Assessment of Atherosclerosis in Apolipoprotein-E Knockout Mice by Ultrasound Biomicroscopy

Intima media thickness is a marker for human atherosclerosis. This study aimed to validate the hypothesis that atherosclerosis progression in vivo in mice can be visualized noninvasively using high-resolution ultrasound biomicroscopy (UBM), and to study the association between UBM characteristics and plasma lipids in the apolipoprotein-E knockout (ApoE-/-) mouse model. Four age groups of male ApoE-/- mice were used as atherosclerotic models, with age-matched male C57BL/6 mice used as controls. Plaque thickness and area measured by UBM correlated with histologic measurements (r = 0.81, r = 0.70, respectively; p < 0.001). Serum total cholesterol, low density lipoprotein cholesterol and triglycerides were higher in the ApoE-/- groups compared with controls (p < 0.01). Plaque thickness was correlated with total cholesterol (r = 0.505, p < 0.001). High-resolution UBM provides a noninvasive, accurate means of detecting atherosclerosis progression in vivo in mice and can detect changes in the early stage of atherosclerosis.

Transthoracic Echocardiographic Findings of Pulmonary Artery Dissection

Pulmonary artery dissection is a rare and fatal disease. To our knowledge, there have been no more than 70 cases reported in the literature. The diagnosis is made mainly at autopsy because many of these patients have sudden death when the main pulmonary artery dissects into the pericardium, causing acute cardiac tamponade. We report a case of pulmonary artery dissection diagnosed by transthoracic echocardiography in a patient with dilatation of the pulmonary artery.

Diagnostic Value of Transthoracic Echocardiography in Patients With Anomalous Origin of the Left Coronary Artery From the Pulmonary Artery

AbstractAnomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital coronary abnormality associated with early infant mortality and sudden death in adults. Transthoracic echocardiography (TTE) plays an important role in early detection and diagnosis of ALCAPA as a noninvasive modality. However, its diagnostic value is not well studied. The purpose of this study is to determine the performance of TTE in the diagnostic assessment of ALCAPA as compared with coronary CT and invasive coronary angiography.A total of 22 patients (13 women and 9 men, mean age, 12.9 ± 19.5 years) with ALCAPA who underwent echocardiographic examination for clinical diagnosis were retrospectively reviewed and analyzed. Transthoracic echocardiographic features of ALCAPA were analyzed and its diagnostic value was compared with invasive coronary angiography and coronary CT angiography (CTA) with surgical findings serving as the gold standard. Surgery was performed in all of the patients to establish the dual coronary artery system. Five underwent the Takeuchi procedure and 17 had re-implantation of the anomalous left coronary artery. Of 20 patients, echocardiographic diagnoses were in good agreement with findings at surgery, resulting in the diagnostic accuracy of 90.9%. Two cases were misdiagnosed—one as the right coronary artery to pulmonary artery fistula and the other as rheumatic heart disease. The echocardiographic features of these patients with ALCAPA included: abnormal left coronary ostium arising from the pulmonary trunk with retrograde coronary artery flow in 20 patients; enlargement of the right coronary artery in 17 patients; abundant intercoronary septal collaterals in 17 patients; and moderate and significant mitral regurgitation in 14 patients. The diagnostic accuracy of invasive coronary angiography (in 17 patients) and coronary CTA (in 9 patients) was 100%.This study shows that TTE is an accurate, noninvasive imaging modality for displaying the origin of coronary arteries and demonstrating the coronary courses as well as other associated abnormalities in patients with ALCAPA.