Wall motion velocities of ascending aorta measured by tissue Doppler imaging in obese children

Background: Obesity is associated with the development of early cardiovascular abnormalities such as atherosclerotic lesions. Arterial stiffness may be an indicator of early vascular changes signaling the development of vascular disease. The objective of the current study was to screen aortic elastic properties with tissue Doppler imaging in obese children. Methods: We examined 37 obese children and 30 age‐ and sex‐matched normal subjects. Anthropometric measurements and metabolic risk profile were assessed in a physical examination and with blood taking. The subjects were divided into two subgroups: those with and without metabolic syndrome. Internal aortic systolic and diastolic diameters by M‐mode echocardiography and aortic systolic upper‐wall tissue velocity by tissue Doppler imaging were measured 3 cm above the aortic valve. Aortic distensibility and aortic stiffness index were calculated using accepted formulae. Results: Aortic stiffness parameters and both tissue Doppler peak systolic and diastolic velocities differed significantly in obese children compared to controls. Among the subgroups, children with metabolic syndrome had a lower aortic stiffness index, aortic distensibility and tissue Doppler velocities. However, only peak diastolic velocities significantly differed between obese children without metabolic syndrome and controls. Homeostatic model scores, diastolic blood pressures and pulse pressures were the strongest to correlate with peak diastolic velocity (r=?0.88, P < 0.001, r=?0.62, P= 0.001 and, r= 0.55, P= 0.001, respectively). Conclusions: Tissue Doppler imaging is a feasible and sensitive method to identify aortic stiffness in obese children. Reduced aortic diastolic velocity is the most prominent early vascular change detected in obese children before metabolic syndrome occurs.     

Intraoperative measurements of cerebral haemodynamics during ductus arteriosus ligation in preterm infants

Intraoperative Doppler sonographic examinations were carried out on seven preterm neonates to measure cerebral blood flow velocity changes in the anterior cerebral arteries during ductus arteriosus ligation. Age at surgery was 12±6 days. Continuous recordings during the operative procedure showed a rapid increase in diastolic blood pressure (P<0.01), whereas systolic blood pressure was not significantly higher compared with pre-occlusion values. In the anterior cerebral arteries, ductal closure led to a decrease in resistance index of Pourcelot (mean=1.02±0.08 vs 0.65±0.07 (P<0.001)) and to an increase in area under the velocity curve (mean=3.64±0.38 vs 8.16±1.07 (P<0.001)). These changes were associated with a corresponding increase of the end diastolic flow velocity (P<0.001) but no change in the peak systolic velocity. The heart rate did not change significantly during ductal closure. TcPO₂, TcPCO₂ remained normal during the study period. These data indicate that changes in cerebral blood flow velocity during surgical ligation are principally determined by changes in systemic diastolic pressure. Systolic blood pressure and peak systolic flow velocity remain unchanged or slightly higher than preligation values, thereby restoring normal cerebral blood flow velocity pattern without increasing the stress on the wall of cerebral vessels and thus the risk of peri-intraventricular haemorrhage.     

Doppler Flow Parameters of Left Ventricular Filling in Infants: How Long Does It Take for the Maturation of the Diastolic Function in a Normal Left Ventricle to Occur?

Objective To study the impact of the maturational process of diastolic left ventricular function on trans-mitral Doppler flow parameters.Methods and Participants In a survey we examined pulsed-wave Doppler signals and diastolic time intervals from 238 healthy neonates and infants. Using multiple linear regression analysis, we evaluated the impact of physiological determinants on parameter expression.Results Early-filling and atrial-filling peak velocities, early-filling acceleration and deceleration rates, and the atrial-filling time velocity integral reached a climax within 2 months after birth, while early-filling time velocity integral followed increasing throughout the study period. The isovolumic relaxation time was found to be significantly longer for neonates than for infants older than 2 months. The observed parameter movements could be attributed to changes of stroke volume and mitral valve area for early filling-time velocity integral (R² = 0.93), and of heart rate, stroke volume, and mitral valve area for early filling peak velocity (R² = 0.84), and atrial-filling time velocity integral (R² = 0.65). Isovolumic relaxation time and atrial-filling peak velocity became heart rate dependent not before 3 months after birth.Conclusions The observed parameter changes are powerful indicators for the maturational process in diastolic function. This process is mainly completed by 3 months of age.     

Mitochondrial myopathy,encephalopathy, lactic acidosis,and stroke-like episodes (MELAS) decrease in diastolic left ventricular function assessed by echocardiography

Summary Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) are known to be associated with cardiomyopathy. Systolic and diastolic left ventricular functions were assessed by M-mode and Doppler echocardiography in four patients with MELAS and in 14 normal controls. The interventricular septal thickness and left ventricular posterior wall thickness were greater (11.0±1.6 mm vs. 5.8±0.7 mm and 11.0±2.2 mm vs. 5.9±0.8 mm) in patients with MELAS than in a control group. Parameters of systolic left ventricular functions (ejection fraction, shortening fraction, systolic time intervals, and mean Vcf) and left ventricular dimensions were not significantly different between the two groups. To assess the diastolic function, blood flow velocity across the mitral valve was measured by Doppler echocardiography and various indexes were obtained. In patients with MELAS, the impairment of diastolic left ventricular filling was demonstrated by decrease in the following indexes: peak flow velocity in the early passive filling period (E) (0.76±0.10 m/s vs. 0.94±0.09 m/s), integrated velocity for total E (10.2±1.3 vs. 13.0±0.9), the ratio of E and late atrial filling integrated velocities (1.72±0.06 vs. 2.49±0.29).     

Acute loads applied to the right ventricle: Effect on left ventricular filling dynamics in the presence of an open pericardium

To determine whether diastolic ventricular interdependence mechanisms would act in the presence of an open pericardial sac, as during cardiac surgery, moderate acute right ventricle afterload increases were applied to eight dogs with the chest and pericardium open while left ventricular filling dynamics were being assessed by Doppler echocardiography. Dogs were studied under basal conditions and after acute banding of the main pulmonary artery tightened to produce a 100% increase in right ventricular systolic pressure. With banding, the left ventricular filling velocity ratio (E/A), as assessed by Doppler echocardiography of mitral inflow, changed from a baseline value of 1.32 ± 0.05 to 1.16 ± 0.03 (p < 0.02), suggesting a restrictive pattern to early left ventricular filling, which is differed to that during the second half of diastole. Isovolumic relaxation time, measured as the time interval between aortic valve closure and mitral valve opening, assessed by M-mode echocardiography of both valves, was prolonged, though not significantly, from 63.3 ± 2.5 ms to 69.4 ± 2.9 ms, by banding of the pulmonary artery. E wave deceleration time, a filling variable influenced by chamber pressure/volume relations, was shortened by pulmonary artery banding, changing from 75.1 ± 1.7 ms to 68.0 ± 1.8 ms (p < 0.01). It was concluded that pressure loads applied to the right ventricle restricted early left ventricular filling. Prolonged relaxation and altered pressure–volume chamber relations were the diastolic interdependence mechanisms involved that proved to be acting even under open pericardium conditions.     

Left Ventricular Systolic Function of Newborns with Asphyxia Evaluated by Tissue Doppler Imaging

The aim of the study was to evaluate the left ventricular systolic function of newborns with asphyxia using tissue Doppler imaging (TDI). Newborns with a history of asphyxia were divided into severe and mild groups based on their Apgar scores; normal newborns without asphyxia served as the controls. Left ventricular ejection fraction (LVEF), fraction shortening (FS), and stroke volume (SV) were measured by M-mode echocardiography at 24, 48, and 72 h after birth. The peak systolic velocity of the anterior mitral valve leaflet (Sm wave) was measured with TDI. Cardiac troponin I (CTnI) was measured. The results revealed that the LVEF and FS of the severe asphyxia group at 24 h were significantly lower than those at later time points (P < 0.01). These parameters were also significantly lower than those of the mild and control groups (P < 0.01). SV was not significantly different among the three groups. Sm wave of asphyxia groups was significantly lower than that of control group (P < 0.001). In the severe asphyxia group, Sm wave at 24 h was significantly lower than that at 48 or 72 h (P < 0.001). CTnI values of the severe asphyxia group were remarkably higher than those of the other two groups (P < 0.01). The findings of this study indicate decreased left ventricular systolic function of newborn children after asphyxia. Sm by TDI is a more sensitive indicator of left ventricular systolic function than LVEF, FS, or SV by M-mode echocardiography.     

Comparison of Tissue Doppler Imaging with MRI T2* and 24-Hour Rhythm Holter Heart Rate Variability for Diagnosing Early Cardiac Impairment in Thalassemia Major Patients

Objectives: Cardiology follow up is important in thalassemia major patients. The object of this study is to define parameters which can be used in the early detection of cardiac impairment. Material and Methods: Forty seven beta thalassemia major patients (mean age 16.3 ± 4.47 years; 22 boys, 25 girls) whose left ventricular systolic functions were normal and a healthy control group of fifty age and gender matched children were included in the study. M-mode echocardiographic measurements, systolic and diastolic functions with PW and tissue Doppler and heart rate variabilities (HRVs) were compared between the two groups. The patients were also grouped according to MRT2*, ferritin and left ventricular diastolic diameters (LVDds) to compare the echocardiographic and Holter parameters among them. Results: None of the children in the study group had symptomatic congestive heart failure. PW Doppler late diastolic forward flow in pulmonary artery was higher in the thalassemia group when compared with the control group (P = 0.01) indicating decreased compliance of the right ventricle. While the systolic and diastolic functions were normal, all the HRV parameters in the thalassemia group were significantly lower than the control group (P = 0.005). Conclusions: Significant decrease in HRV and increase in PW late diastolic forward flow in pulmonary artery in the absence of systolic or diastolic dysfunction, points out that these parameters can be useful in detection of early cardiac impairment.     

原发性高血压儿童血尿酸水平与心脏亚临床损伤的相关性

目的 评估原发性高血压儿童的心脏亚临床损害情况,并分析血尿酸水平与心脏亚临床损害的相关性。方法 回顾性分析2015年1月至2020年6月于苏州大学附属儿童医院心血管内科住院的55例原发性高血压患儿治疗前的临床资料,并选取该院同期同年龄、同性别的45例健康体检儿童作为对照组。分析两组儿童临床特征、实验室检查、左心结构、收缩和舒张功能指标的差异,并探讨高血压患儿血尿酸水平与其左心结构、收缩和舒张功能指标的相关性。结果 高血压组左心室质量、左心室质量指数及相对室壁厚度显著高于对照组（P < 0.05）,并有20例（36%）出现左心室肥厚。高血压组左心房内径和主动脉根部内径也显著高于对照组（P < 0.05）。高血压组二尖瓣口舒张早期峰值流速/二尖瓣环舒张早期速度的比值显著高于对照组（P < 0.05）。相关分析显示,血尿酸水平与原发性高血压患儿左心室质量（r=0.534,P < 0.01）、左心房内径（r=0.459,P < 0.01）、主动脉根部内径（r=0.361,P=0.010）呈正相关;校正血压影响后血尿酸水平仍与上述指标呈正相关（P < 0.05）。结论 原发性高血压患儿可出现左心室肥厚、舒张功能受损、左心房及主动脉近端扩张等亚临床损害。血尿酸水平增加与原发性高血压患儿心脏损害显著相关。     

CARDIAC FUNCTIONS EVALUATED WITH TISSUE DOPPLER IMAGING IN CHILDHOOD CANCERS TREATED WITH ANTHRACYCLINES

Aim: The aim of this study was to assess the cardiac functions using conventional echocardiography and tissue Doppler imaging in childhood cancers treated with anthracyclines. Methods: The study group was selected from the patients admitted to the pediatric oncology department for a treatment protocol that included doxorubicin. Body surface area was calculated and complete 2-dimensional, M-mode, pulse wave Doppler and pulse wave tissue Doppler echocardiographic examinations were performed just before the first treatment and at least 6 months after the last treatment. Results: This study included 20 patients (12 males and 8 females). Mean cumulative antracycline dose was 189 ± 102.90 mg/m². There were no significant differences between the pre- and post-treatment groups regarding systolic and diastolic blood pressures, heart rates, left ventricular ejection fraction and fractional shortening, right and left ventricular conventional and tissue Doppler diastolic parameters (E and A waves, E/A ratio, E′ and A′ waves, E′/A′ ratio), but there were significant differences between the pre- and post-treatment groups regarding body surface area, right and left ventricular myocardial performance index observed by conventional pulse wave and pulse wave tissue Doppler methods. Conclusion: Tissue Doppler imaging provided additional information on cardiac functions. While systolic and diastolic functions were in normal range, myocardial performance index observed by tissue Doopler method was impaired in children who were treated with anthracyclines.     

M-mode echocardiographic findings in children with idiopathic restrictive cardiomyopathy

Summary The M-mode echocardiographic findings in five pediatric patients, ages 4–15 years, with primary idiopathic restrictive cardiomyopathy, diagnosed by cardiac catheterization, and of 12 normal children (control group) are presented. The M-mode echocardiographic findings in patients with restrictive cardiomyopathy were (1) normal left and right ventricular end-diastolic dimension, (2) normal left ventricular posterior wall and interventricular septal thickness (three patients) or mild concentric hypertrophy (two patients), (3) normal opening and closing velocity of the mitral valve, (4) consistently enlarged left atrium (more than 40 mm) in all, and (5) right ventricular systolic time intervals compatible with pulmonary artery hypertension. The left ventricular ejection phase parameters (systolic time intervals, shortening fraction, and mean velocity of circumferential fiber shortening) were normal. Left ventricular relaxation phase parameters (diastolic function) were abnormal. The isovolumic relaxation time index was prolonged, 68±40 ms (±SD), in the study group as compared with 11±6 ms (±SD) in the control group (P<0.001). Percent relaxation of left ventricular posterior wall endocardium at 50% of diastole was decreased, 58±4% (±SD), in the study group as compared with 85±6% (±SD) in the control group (P<0.005). We conclude that M-mode echocardiography provides arelatively useful and specific noninvasive method for the diagnosis of primary restrictive cardiomyopathy in pediatric patients. This work was supported in part by NHLBI grant HL07436.     

Effects of low-dose dobutamine on left ventricular diastolic filling in children

To investigate the effects of dobutamine on the Doppler transmitral flow pattern in children with normal left ventricular function, Doppler echocardiography was used to measure the transmitral flow in 14 healthy children before and during infusion of dobutamine (5 μg/kg per minute). Cardiac output was measured by the thermodilution method, and stroke volume was calculated as the cardiac output divided by the heart rate. Dobutamine increased the peak velocity and flow velocity–time integral of early diastolic filling without changing those of atrial contraction and normalized peak velocity of early diastolic filling, suggesting an increase in left ventricular relaxation. Dobutamine increased the stroke volume and rate-corrected mean velocity of fiber shortening with reduced end-systolic wall stress, indicating an increase in left ventricular contractility. The percentage of increase in the flow velocity–time integral of early diastolic filling during dobutamine infusion tended to correlate with the increase in stroke volume (r= 0.67, p < 0.05) and with the decrease in end-systolic wall stress (r=−0.61, p < 0.05). Our results suggest that low-dose dobutamine increases left ventricular relaxation with enhanced systolic function. The observed decreased end-systolic wall stress might have caused enhanced relaxation characteristics with dobutamine.     

Brain Natriuretic Peptide as a Hormonal Marker of Ventricular Diastolic Dysfunction in Children with Kawasaki Disease

Although an increased level of serum brain natriuretic peptide (BNP) has been reported in children in the acute phase of Kawasaki disease (KD), no precise relation was documented between the serum BNP level and left ventricular (LV) systolic function. We hypothesized that the increased BNP levels may be explained by diastolic abnormalities in those with KD. We prospectively studied 25 patients in the acute phase of KD. Patients with abnormal systolic function were excluded. Pediatric cardiologists making the assessment of LV diastolic function were blinded to the BNP levels. Doppler interrogation was applied to measure LV inflow velocities, which were transformed to z scores using control measurements obtained from 83 healthy subjects. In the patients, the BNP levels ranged from 2.0 to 450.0 pg/ml, with a mean of 54.0 ± 102.8 pg/ml. Six patients with abnormal velocities (> 2 SD in z score) showed significantly higher levels of BNP (152 ± 173 pg/ml) than those in the remaining patients (p < 0.01). The BNP levels correlated positively with diastolic atrial velocity in z score (r = 0.51, p < 0.05), and negatively with diastolic early velocity to atrial velocity ratio in z score (r = -0.75, p < 0.01). This study suggests that LV diastolic dysfunction may occur in some children in the acute phase of KD, causing an increased level of BNP.     

The late consequences of anthracycline treatment on left ventricular function after treatment for childhood cancer

The purpose of this study was to determine the incidence of changes in left ventricular function in patients in long-term remission after treatment with anthracyclines for a childhood malignancy. The authors examined 155 patients in disease remission who underwent treatment protocols utilising anthracyclines in childhood. The group comprised 90 males and 65 females aged 15±4.9 years (range 5–29 years, median 15 years). The age at the time of diagnosis and start of treatment was 8.6±4.9 years (range 1–18 years, median 8 years). The time of follow-up was 7.3±4 years (range 1–21 years, median 6.3 years). The patients were given a cumulative dose of doxorubicin or daunorubicin of 250±131 mg/m² (range 50–1200 mg/m², median 240 mg/m²). The values of ejection fraction below 55% and fractional shortening below 30% assessed by means of echocardiography were considered as pathological. The control group consisted of 41 volunteers. Pathological values of fractional shortening were found in 12 patients (8%). Only one patient (0.64%) showed the development of heart failure due to cardiomyopathy. The group of the patients after chemotherapy revealed significantly worse values of left ventricular endsystolic wall stress, mean velocity of circumferential fibre shortening, Tei index, and isovolumic relaxation period in comparison with the control group. We found a correlation between the given cumulative dose of anthracyclines and indicators of systolic function of the left ventricle, but not a relation to the time indicators (age at diagnosis, time of follow-up). Conclusion:in the mean period of 6 years after chemotherapy, subclinical cardiotoxicity was found in 11 patients (7%) and cardiomyopathy with heart failure in one patient. Further indicators of subclinical damage are elevation of afterload (end-systolic stress), impaired relaxation and increased value of the Doppler index of global left ventricular function. Further monitoring and evaluation of the relevant subclinical abnormalities over a longer period of time are needed.Abbreviations CD cumulative dose - DT deceleration time - E/A index of the diastolic filling of the left ventricle - EF ejection fraction - ESS end-systolic stress - FS fractional shortening - HR heart rate - IRT isovolumic relaxation time - LV left ventricle - LVPWDd end-diastolic diameter of the left ventricular posterior wall - LVPWex excursion of the left ventricular posterior wall - LVPWP percentage of the systolic thickening of the left ventricular posterior wall - MPI myocardial performance index - mVcf _c mean velocity of circumferential fibre shortening     

Early Echocardiographic Findings in ��-Thalassemia Intermedia Patients Using Standard and Tissue Doppler Methods

Heart complications are among the serious problems of patients with β-thalassemia intermedia. This study aimed to evaluate myocardial function in these patients. Clinical parameters and both standard Doppler and pulsed Doppler tissue imaging parameters were compared in 51 β-thalassemia intermedia patients (mean age, 17.05 ± 5.8 years) and 20 normal subjects (mean age, 17.81 ± 7.35 years, p = 0.98). In 11 patients (21.5%), pulmonary artery hypertension was detected. M-mode echocardiographic findings such as ejection fraction and fractional shortening did not show statistically significant changes (p > 0.005). Pulsed Doppler showed a significant difference in the early (E) to late diastolic (A) velocity ratio of the tricuspid and mitral valve between the patients and the control subjects (p < 0.05). In the pulsed tissue Doppler study, the peak systolic velocity of the septum (Ss), the peak atrial velocity of the septum (Aas), the peak systolic velocity of the tricuspid annulus (St), the peak early diastolic velocity of the tricuspid annulus (Eat), and the peak late diastolic velocity of the tricuspid annulus (Aat) were increased significantly (p < 0.05). The pulse tissue Doppler of the lateral mitral annulus did not change significantly (p > 0.005). The peak systolic velocity of the posterior wall and the peak late diastolic velocity of the anterior wall changed significantly (p < 0.05). This study showed that β-thalassemia intermedia patients with normal M-mode and two-dimensional echocardiography had statistically significant changes in pulsed Doppler and pulsed tissue Doppler imaging.     

Body Mass Index Can Predict Left Ventricular Diastolic Filling in Asymptomatic Obese Children

To examine the effects of body mass index on left ventricular diastolic function, flow velocity patterns of the pulmonary vein and mitral valve were measured by pulse Doppler echocardiography in 21 asymptomatic obese children and were compared with those of an age-matched control population. The degree of obesity was calculated as (actual body mass index/ideal body mass index -1) x 100. The pulmonary venous flow indexes were peak systolic (S) and diastolic (D) velocities and peak D/S. The mitral inflow indexes were peak velocities of early diastole (E) and atrial contraction (A) and peak E/A. The pulmonary venous flow velocity pattern in obese patients was characterized by unchanged peak S, decreases in peak D (43 +/- 7 vs 51 +/- 8, p < 0.01) and peak D/S (0.98 +/- 0.19 vs 1.29 +/- 0.20, p < 0.01), suggesting the reduction in the early diastolic filling. The peak D/S decreased significantly with an increase in the percentage body mass index (r = -0.84, p < 0.01). In contrast to the pulmonary venous flow pattern (peak D > peak S) as seen in normal controls, all of the obese patients with > 70% over body mass index had abnormal pulmonary venous flow velocity patterns (peak D < peak S). The mitral flow velocity pattern in obese patients was also characterized by a decrease in early diastolic filling. However, these indices did not correlate with an increase in the percentage over body mass index. This study suggests that body mass index predicts the abnormality of left ventricular diastolic filling assessed by pulmonary venous flow patterns.     

X-Chromosomal (p21) Muscular Dystrophy and Left Ventricular Diastolic and Systolic Function

In order to screen for cardiac abnormalities, we prospectively studied 15 patients (age 8–25 years, mean 15.5 years) with Duchenne's (DMD) (n= 9) and Becker's (BMD) (n= 6) muscular dystrophy using the echocardiogram. Data were compared to a control group of 92 healthy individuals (age 7.9–25 years, mean 14.3 years). Left ventricular filling in diastole showed a different pattern when comparing echocardiographic Doppler results in patients and controls: Patients had lower peak velocity of early left ventricular diastolic filling (E-vmax)(P < 0.0001) and smaller time velocity integral of the E-wave (E-tvi)(P < 0.0001). In contrast, the atrial component (A-vmax, A-tvi) of diastolic filling in DMD/BMD showed no significant difference to controls. The mean area of the mitral valve orifice was significantly larger in patients (P < 0.0001) without presence of mitral regurgitation. Systolic left ventricular function was significantly impaired in the DMD/BMD group; we found lower heart rate corrected fiber shortening velocity VCFc (P < 0.001) and higher peak systolic wall stress (P < 0.001) in DMD/BMD. In 8 of 15 patients, peak systolic wall stress was above 95th percentile of controls. In 6 of 15 patients, VCFc was lower than the 5th percentile of controls. Systolic and diastolic myocardial impairment was found even in young patients and at low stages of disability—equally among patients with DMD or BMD. Diastolic left ventricular impairment predominantly affected the early diastolic filling, but atrial compensation was poor. Peak systolic wall stress measurements were particularly useful in patients with CMP, reflecting the left ventricular afterload.     

Assessment of cardiac function in absence of congenital and acquired heart disease in patients with Down syndrome

Background

Extra genetic material in patients with Down syndrome (DS) may affect the function of any organ system. We evaluated cardiac functions using conventional tissue Doppler and two-dimensional speckle tracking echocardiography in patients with DS in the absence of congenital and acquired heart disease in patients.

Methods

A total of 115 patients with DS between 6 and 13 years of age with clinically and anatomically normal heart and 55 healthy children were included in this cross-sectional study. DS was diagnosed by a karyotype test. Patients with mosaic type were not included in this study. Systolic and diastolic functions were evaluated by echocardiography.

Results

Pulsed waved Doppler transmitral early/late inflow velocity (E/A), tissue Doppler mitral annular early/late diastolic peak velocity (Ea/Aa), transtricuspid E/A and tricuspid valve annulus Ea/Aa, pulmonary venous Doppler systolic/diastolic (S/D) wave ratio were lower in patients with Down syndrome than in the control group (P=0.04, P=0.001, P<0.05, P<0.001, P<0.001, respectively). Mitral and tricuspid annular Ea were lower in patients with DS (P<0.001). The right and left ventricular myocardial performance indexes were higher in patients with DS than in the controls (P<0.01). They had significantly higher left ventricular mass, ejection fraction, the mitral annular plane systolic excursion values. However, the Down syndrome group compared with the controls had a lower strain values examined by two-dimensional longitudinal speckle-tracking strain echocardiography.

Conclusion

These findings suggest conventional tissue Doppler and two-dimensional longitudinal speckletracking strain echocardiography were useful methods of investigating ventricular function and identifying a higher incidence of biventricular dysfunction in patients with Down syndrome compared with the healthy controls.

     

Assessment of right ventricular diastolic filling parameters by Doppler echocardiography

BACKGROUND: Right ventricular diastolic function has been evaluated in various diseases by the pulsed Doppler technique. Right ventricular diastolic filling parameters show changes with age, heart rate and respiration. Evidences of diastolic left and right ventricular dysfunctions have been reported by echocardiographic studies in asthmatic patients. In the present study, before and after treatment of asthma the right ventricular diastolic filling parameters were compared in children with moderate asthma by Doppler echocardiography (a non-invasive technique). METHODS: The study group consisted of 20 children (eight girls, 12 boys) with asthma. During the present study these patients were treated with inhaled steroid and beta-2 agonist daily. Before treatment all patients were evaluated by Doppler echocardiography. At 4-6 weeks after treatment 15 patients that had shown improvement in their symptoms according to the symptom score were also evaluated by Doppler echocardiography. RESULTS: The mean age was 8.6 +/- 2.69 years and mean period of symptoms were 56.4 +/- 35.8 months. When compared with results of echocardiography before and after treatment, the right ventricular diastolic filling parameters (acceleration time: P < 0.01, deceleration time: P < 0.01 and isovolumetric relaxation time: P < 0.05) were found to be significantly different. CONCLUSIONS: We observed significant improvement of right ventricular diastolic filling parameters by Doppler echocardiography after treatment in children with asthma.     

Comparison of Doppler parameters of central versus intraparenchymal renal arteries in physiologically normal newborns

Background: Changes in renal arterial Doppler flow may identify parenchymal disease, but in newborns knowledge of normal physiological parameters is a prerequisite for correct interpretation. Objective: To evaluate renal blood flow in healthy newborns by means of Doppler US. Materials and methods: On the fourth day of life we examined 100 normal term newborn infants (200 kidneys). Blood flow in the central renal arteries was compared with that in the intraparenchymal arteries. Maximum systolic velocity (V_max), end-diastolic velocity (V_ed), mean flow velocity (V_mean), resistive index (RI) and pulsatility index (PI) were assessed. Results: All parameters were significantly higher in the central renal arteries than in the intraparenchymal arteries (RI 0.78±0.07 vs 0.62±0.05, P<0.0001; PI 1.84±0.52 vs 1.09±0.18, P<0.0001). Conclusions: Physiological data are presented that are necessary for the correct interpretation of neonatal Doppler US.     

Posterior Descending Coronary Artery Flow Reserve Assessment by Doppler Echocardiography in Children with and without Congenital Heart Defect Comparison with Invasive Technique

To evaluate whether transthoracic Doppler echocardiography can reliably measure coronary flow velocity and coronary flow velocity reserve (CFVR) in the posterior descending coronary artery (PD) in children, we examined 32 patients who had congenital heart disease (ventricular septal defect in 10, tetralogy of Fallot in 6, tricuspid atresia in 3, double-outlet right ventricle in 2, patent ductus arteriosus in 2, and aortic valve stenosis in 2) and 7 patients who had a history of Kawasaki disease without stenosis or aneurysm formation of the coronary artery. Average peak flow velocity (APV) in the PD was measured by transthoracic Doppler echocardiography at the time of intracoronary Doppler study. CFVR was defined as the ratio of hyperemic to basal APV. Clear envelopes of basal and hyperemic APV in the PD were obtained in 23 of 32 patients by transthoracic Doppler echocardiography. APV obtained from transthoracic Doppler echocardiography correlated highly with that from the Doppler guidewire method (r = 0.91). The mean difference between transthoracic Doppler echocardiography and the Doppler guidewire method was 0.1 ± 2.9. There was an excellent correlation between transthoracic Doppler echocardiography and the Doppler guidewire method for the measurements of CFVR (r = 0.84). The mean difference between transthoracic Doppler echocardiography and Doppler guidewire was –0.016 ± 0.198. Noninvasive measurement of coronary flow velocity and CFVR in the PD using transthoracic Doppler echocardiography accurately reflects invasive measurement of coronary flow velocity and CFVR by the Doppler guidewire method in pediatric patients with various heart diseases.