Comparison of myocardial function in children with body mass indexes >/=25 versus those <25 kg/m2

Obesity and Weight Loss Strategies for Patients With Heart Failure

Obesity is a common comorbidity among patients with heart failure with reduced ejection fraction (HFrEF) or heart failure with preserved ejection fraction (HFpEF), with the strongest pathophysiologic link of obesity being seen for HFpEF. Lifestyle measures are the cornerstone of weight loss management, but sustainability is a challenge, and there are limited efficacy data in the heart failure (HF) population. Bariatric surgery has moderate efficacy and safety data for patients with preoperative HF or left ventricular dysfunction and has been associated with reductions in HF hospitalizations and medium-term mortality. Antiobesity medications historically carried concerns for cardiovascular adverse effects, but the safety and weight loss efficacy seen in general population trials of glucagon-like peptide 1 (GLP-1) and gastric inhibitory polypeptide/GLP-1 agonists are highly encouraging. Although there are safety concerns regarding GLP-1 agonists in advanced HFrEF, trials of the GLP-1 agonist semaglutide for treatment of obesity have confirmed safety and efficacy in patients with HFpEF.

Heart Failure with Preserved Ejection Fraction in Children

Diastolic dysfunction (DD) refers to abnormalities in the mechanical function of the left ventricle (LV) during diastole. Severe LVDD can cause symptoms and the signs of heart failure (HF) in the setting of normal or near normal LV systolic function and is referred to as diastolic HF or HF with preserved ejection fraction (HFpEF). Pediatric cardiologists have long speculated HFpEF in children with congenital heart disease and cardiomyopathy. However, understanding the risk factors, clinical course, and validated biomarkers predictive of the outcome of HFpEF in children is challenging due to heterogeneous etiologies and overlapping pathophysiological mechanisms. The natural history of HFpEF varies depending upon the patient's age, sex, race, geographic location, nutritional status, biochemical risk factors, underlying heart disease, and genetic-environmental interaction, among other factors. Pediatric onset HFpEF is often not the same disease as in adults. Advances in the noninvasive evaluation of the LV diastolic function by strain, and strain rate analysis with speckle-tracking echocardiography, tissue Doppler imaging, and cardiac magnetic resonance imaging have increased our understanding of the HFpEF in children. This review addresses HFpEF in children and identifies knowledge gaps in the underlying etiologies, pathogenesis, diagnosis, and management, especially compared to adults with HFpEF.

Therapeutic Approaches in Heart Failure with Preserved Ejection Fraction (HFpEF) in Children: Present and Future

For a long time, pediatric heart failure (HF) with preserved systolic function (HFpEF) has been noted in patients with cardiomyopathies and congenital heart disease. HFpEF is infrequently reported in children and instead of using the  HFpEF terminology the HF symptoms are attributed to diastolic dysfunction. Identifying HFpEF in children is challenging because of heterogeneous etiologies and unknown pathophysiological mechanisms. Advances in echocardiography and cardiac magnetic resonance imaging techniques have further increased our understanding of HFpEF in children. However, the literature does not describe the incidence, etiology, clinical features, and treatment of HFpEF in children. At present, treatment of HFpEF in children is extrapolated from clinical trials in adults. There are significant differences between pediatric and adult HF with reduced ejection fraction, supported by a lack of adequate response to adult HF therapies. Evidence-based clinical trials in children are still not available because of the difficulty of conducting trials with a limited number of pediatric patients with HF. The treatment of HFpEF in children is based upon the clinician's experience, and the majority of children receive off-level medications. There are significant differences between pediatric and adult HFpEF pharmacotherapies in many areas, including side-effect profiles, underlying pathophysiologies, the β-receptor physiology, and pharmacokinetics and pharmacodynamics. This review describes the present and future treatments for children with HFpEF compared with adults. This review also highlights the need to urgently test new therapies in children with HFpEF to demonstrate the safety and efficacy of drugs and devices with proven benefits in adults.

The effect of overweight/obesity on diastolic function in children and adolescents: A meta-analysis

Left ventricular diastolic function (LVDF) is an important marker of early cardiovascular remodelling, which has not been well summarized in young people with overweight/obesity. Weighted, random-effects regression was used to determine the strength of associations of both body mass index (BMI) and homeostatic model assessment of insulin resistance (HOMA-IR) with LVDF measures, adjusting for age and sex. Six databases were searched after PROSPERO registration (CRD42020177470) from inception to July 2020 for studies that compared LVDF between overweight/obesity and control groups aged ≤24 years, yielding 70 studies (9983 individuals). Quality and risk of bias were assessed using NHLBI tools, with scores of good, fair, and poor for 6, 48, and 16 studies, respectively. Increased BMI was associated with worse LVDF in all measures except early mitral inflow deceleration time, with septal early diastolic tissue peak velocity to late diastolic tissue peak velocity ratio having the strongest association (n = 13 studies, 1824 individuals; r = -0.69; P < 0.001). Elevated HOMA-IR was also associated with worse LVDF. Although we could not determine the causality of reduced LVDF in young people, our findings should aid the development of paediatric guidelines for the assessment of LVDF and support further work to address the longitudinal consequences of childhood obesity and IR on LVDF.

Anemia and Its Effect on Cardiovascular Findings in Obese Adolescents

Objective

We assessed the effect of anemia on cardiovascular findings in obese adolescents.

Materials and Methods

We studied 29 anemic and 33 nonanemic obese adolescents, and 33 nonobese healthy adolescents. These three groups were investigated for clinical and laboratory features of anemia and obesity. Echocardiography was used to examine cardiac functions.

Results

The anemia was mild (mean hemoglobin: 11.67±0.79g/dL), ferritin level was significantly low, and C-reactive protein and fibrinogen levels were significantly high in anemic obese patients. Increased cardiac pulse and echocardiographic findings, which may be indicative of early left ventricular diastolic dysfunction, were present in these patients.

Conclusion

Anemia may develop due to iron deficiency and chronic inflammation in obese adolescents. Even mild anemia may cause increased heart rate and affect left ventricular diastolic functions. Diet programs for obese children should be carefully planned to avoid iron deficiency anemia, which may worsen the cardiac events in long-term follow-up.

Dynamic thiol/disulphide homeostasis as a novel indicator of oxidative stress in obese children and its relationship with inflammatory-cardiovascular markers

Objective:

Childhood obesity is an important cause of cardiovascular risk with chronic inflammation. Oxidative stress may contribute to the pathogenesis of obesity-related cardiovascular pathologies. We aimed to evaluate thiol/disulphide homeostasis as a novel and sensitive marker of oxidative stress and to evaluate its relationship with some inflammatory and cardiovascular markers in obese children.

Methods:

In this case-controlled study, 65 children with exogenous obesity and 64 healthy children, as a control group, were included. In both groups, thiol/disulphide homeostasis parameters and inflammatory (white blood cells, platelets, mean corpuscular volume, neutrophil/lymphocyte ratio, and high-sensitivity C-reactive protein) and cardiovascular (epicardial adipose tissue thickness and left ventricular mass index) markers were studied. Correlation analyses of thiol/disulphide homeostasis parameters with body mass index standard deviation scores (BMI SDS) and inflammatory and cardiovascular markers were performed. Receiver-operating characteristic analysis was performed to determine the sensitivity, specificity, and optimal cut-off values of thiol/disulphide homeostasis parameters.

Results:

Native thiol, total thiol, and native thiol/total thiol ratios (antioxidant parameters) were lower (p<0.05) and disulphide/native thiol and disulphide/total thiol ratios (oxidant parameters) were higher in the obese group than in the control group (p<0.01). A positive correlation of oxidant parameters with BMI SDS and inflammatory markers was found. However, a negative correlation of antioxidant parameters with BMI SDS and inflammatory markers was found. The specificities of disulphide/native thiol and disulphide/total thiol ratios were higher in the obese group.

Conclusion:

The impairment in thiol/disulphide homeostasis, which is indicative of oxidative stress, is associated with inflammation in obesity. In addition, cardiovascular involvement may also contribute to this impairment.

Cardiovascular effects of metabolic syndrome after transplantation: convergence of obesity and transplant-related factors

Children are at increased risk of developing metabolic syndrome (MS) after kidney transplantation, which contributes to long-term cardiovascular (CV) morbidities and decline in allograft function. While MS in the general population occurs due to excess caloric intake and physical inactivity, additional chronic kidney disease and transplant-related factors contribute to the development of MS in transplant recipients. Despite its significant health consequences, the interplay of the individual components in CV morbidity in pediatric transplant recipients is not well understood. Additionally, the optimal methods to detect early CV dysfunction are not well defined in this unique population. The quest to establish clear guidelines for diagnosis is further complicated by genetic differences among ethnic groups that necessitate the development of race-specific criteria, particularly with regard to individuals of African descent who carry the apolipoprotein L1 variant. In children, since major CV events are rare and traditional echocardiographic measures of systolic function, such as ejection fraction, are typically well preserved, the presence of CV disease often goes undetected in the early stages. Recently, new noninvasive imaging techniques have become available that offer the opportunity for early detection. Carotid intima-media thickness and impaired myocardial strain detected by speckle tracking echocardiography or cardiac magnetic resonance are emerging as early and sensitive markers of subclinical CV dysfunction. These highly sensitive tools may offer the opportunity to elucidate subtle CV effects of MS in children after transplantation. Current knowledge and future directions are explored in this review.

Comparison of echocardiographic findings with laboratory parameters in obese children

Aim The purpose of our study was to evaluate the association between insulin resistance and left ventricular size and function in obese children. Material and methods A total of 79 cases aged 10-16 years and diagnosed with obesity and 79 healthy and non-obese cases as controls were included in the study. Patient and control groups were divided into three groups in terms of age as group 1 (10-12 years), group 2 (12-14 years), and group 3 (14-16 years). Fasting blood glucose, lipid profile, and fasting insulin levels of the cases were assessed. Mitral valve E and A waves, left ventricular ejection fraction, fractional shortening, end-diastolic and end-systolic diameters, left atrium diameter, and septal wall thickness were measured using echocardiography.

RESULTS

Measurements of septal diastolic thicknesses, left atrium diameter, and left ventricular end-systolic diameter of all the three groups obtained by echocardiography were statistically higher compared with the controls. In all the patient groups, the mitral valve E/A ratio was >1. In groups 2 and 3, there was a positive correlation between fasting insulin levels and HOMA-IR and left ventricular end-systolic diameter, end-diastolic diameter, and septal systolic and diastolic wall thicknesses.

CONCLUSION

In paediatric obesity, identification of early cardiac changes will be significant in allowing early diagnosis and treatment of cardiovascular diseases.

Assessment of left ventricular mass index could predict metabolic syndrome in obese children

BACKGROUND

Childhood obesity is a major risk factor for cardiovascular diseases in children and adults.

OBJECTIVES

The purpose of this study was to evaluate the serum leptin level and the cardiac changes in normotensive obese children and to study the relationship between left ventricular mass index (LVMI) and serum leptin with the parameters of metabolic syndrome (MS) in obese children.

METHODS

This study was conducted in al Jeddani Hospital and Ibn Sina College Hospital in Saudi Arabia in the period from July 2012 to December 2013, and included 82 obese children. Their mean age was 10.2 ± 2.8 years; they were divided into 25 obese children with MS and 57 obese children without MS, and 40 healthy age- and sex-matched children were also included in the study as a control group. All children were subjected to clinical assessment including standing height, body weight, body mass index (BMI), waist circumference (WC), and blood pressure measurements. All children received an echocardiographic examination (2-dimensional, M-mode, Doppler, and tissue Doppler echocardiograpy) and laboratory assessment of serum leptin level, fasting glucose, fasting insulin, the homeostatic model assessment for insulin resistance (HOMA) index, total cholesterol, triglycerides, and high- and low-density lipoprotein profile.

RESULTS

BMI, BMI standard deviation score, WC, fasting glucose, fasting insulin, HOMA index and the serum leptin level were significantly higher in obese children compared to control group (p < 0.05). The LVMI were increased in the obese compared to the control group (p < 0.001) while left ventricle systolic and diastolic functions did not differ in obese versus control group (p > 0.05). There was a significant positive correlation between both LVMI and serum leptin level in comparison to BMI, WC, fasting glucose, fasting insulin, HOMA, triglycerides, and low-density lipoprotein in all obese children, especially the MS group. However, there was a significant negative correlation between both LVMI and serum leptin level in comparison to high-density lipoprotein.

CONCLUSION

Assessment of LVMI as routine echocardiographic examinations and serum leptin level might be a feasible and reliable method for the evaluation of obesity and its related cardiovascular risks during childhood that can predict metabolic syndrome and insulin resistance.

Cardiac Abnormalities in Youth with Obesity and Type 2 Diabetes

Childhood obesity has been linked to cardiovascular disease (CVD) risk in adulthood. Of great concern is the expected increase in the population's CVD burden in relation to childhood obesity. This is compounded by the risk related to chronic hyperglycemia exposure in youth with type 2 diabetes. We herein provide an overview of the spectrum of early cardiovascular disease manifestation in youth with obesity and type 2 diabetes, in particular abnormalities in cardiac structure and function. Cardiac remodeling and adverse target organ damage is already evident in the pediatric age group in children with obesity and type 2 diabetes. This supports the importance of intensifying obesity prevention efforts and early intervention to treat comorbidities of obesity in the pediatric age group to prevent cardiac events in early adulthood.

The role of blood pressure, body weight and fat distribution on left ventricular mass, diastolic function and cardiac geometry in children

BACKGROUND

Hypertension and obesity in childhood are related to early cardiac damage, as left ventricular hypertrophy. Few studies have analyzed the independent effects of hypertension and weight excess on diastolic function and left ventricular geometry.

OBJECTIVE

We studied the effects of weight, waist circumference (as an index of fat distribution) and blood pressure on left ventricular mass index, the risk of left ventricular hypertrophy, diastolic function and left ventricular geometry in 526 children (237 girls, age range 6-15 years).

METHODS

Children were divided into normotensive, prehypertensive and hypertensive (US Nomograms) groups, and into normal-weight, overweight, and obese (International Obesity Task Force classification) groups. Left ventricular mass index, diastolic function and left ventricular geometry were assessed.

RESULTS

SBP z-scores and blood pressure categories significantly influenced cardiac mass (P < 0.001 and P = 0.02, respectively) and the prevalence of left ventricular hypertrophy (P < 0.001 and P < 0.05, respectively). Obesity, BMI, and waist circumference z-scores were significantly associated with an increment in E/Em ratio (P < 0.001, P < 0.01, and P < 0.01, respectively). Increasing blood pressure values and the presence of prehypertension (P < 0.05) and hypertension (P < 0.003), but not weight excess, were associated with concentric cardiac remodeling. In contrast, concentric hypertrophy was associated with hypertension (P < 0.01), obesity (P < 0.001), and increasing waist circumference (P < 001).

CONCLUSIONS

Blood pressure values and hypertension are independently associated with an increase of cardiac mass and the presence of cardiac hypertrophy. Obesity and waist circumference, but not hypertension, are associated with a worsening of diastolic function, whereas only hypertensive children show high prevalence of concentric remodeling. Blood pressure and body weight and fat distribution have an independent and different impact on left ventricular structure and function in children.

Lifetime risk: childhood obesity and cardiovascular risk

In a recent report, the worldwide prevalence of childhood obesity was estimated to have increased by 47% between 1980 and 2013. As a result, substantial concerns have been raised about the future burden of cardiovascular (CV) disease that could ensue. The purpose of this review is to summarize and interpret (i) the evidence linking early life obesity with adverse changes in CV structure and function in childhood, (ii) the lifetime risk for CV disease resulting from obesity in childhood, and (iii) the potential effects of lifestyle interventions in childhood to ameliorate these risks.

Are the children and adolescents with congenital heart disease living in Southwestern Ontario really overweight and obese?

OBJECTIVE

To assess the prevalence of overweight and obesity in children with congenital heart disease and compare them with age-matched healthy children in Southwestern Ontario, Canada.

METHODS

We compared the Center of Disease Control weight and body mass index z-scores of 1080 children, aged 2 to 18 years, who presented to our paediatric cardiology outpatient clinic from 2008 to 2010 for congenital heart disease with 1083 healthy controls.

RESULTS

In all, 18.2% of the children with congenital heart disease and 20.8% of healthy children were identified to be either overweight or obese. Overall, the weight category distribution had been similar between the congenital heart disease and healthy control groups, as well as between the congenital heart disease subgroups. There was no difference in normal weight and overweight/obese categories between children with congenital heart disease and healthy children. The underweight category, however, showed a significantly higher prevalence in congenital heart disease compared with healthy children (6.8 and 4.5%, respectively, p = 0.03).

CONCLUSION

The prevalence of overweight/obesity did not differ in children with congenital heart disease compared with age-matched healthy children; however, it is still high (18.2%). Obesity may represent an additional risk factor for the long-term cardiovascular health of congenital heart disease patients aside from the underlying heart defect.

Increased regional deformation of the left ventricle in normal children with increased body mass index: implications for future cardiovascular health

The prevalence of obesity continues to increase in the developing world. The effects of obesity on the cardiovascular system include changes in systolic and diastolic function. More recently obesity has been linked with impairment of longitudinal myocardial deformation properties in children. We sought to determine the effect of increased body mass index (BMI) on cardiac deformation in a group of children taking part in the population-based Southampton Women's Survey to detect early cardiovascular changes associated with increasing BMI before established obesity. Sixty-eight children at a mean age of 9.4 years old underwent assessment of longitudinal myocardial deformation in the basal septal segment of the left ventricle (LV) using two-dimensional speckle tracking echocardiography. Parameters of afterload and preload, which may influence deformation, were determined from cardiac magnetic resonance imaging. BMI was determined from the child's height and weight at the time of echocardiogram. Greater pediatric BMI was associated with greater longitudinal myocardial deformation or strain in the basal septal segment of the LV (β = 1.6, p < 0.001); however, this was not related to contractility or strain rate in this part of the heart (β = 0.001, p = 0.92). The end-diastolic volume of the LV increased with increasing BMI (β = 3.93, p < 0.01). In young children, regional deformation in the LV increases with increasing BMI, whilst normal contractility is maintained. This effect may be explained by the increased preload of the LV associated with increased somatic growth. The long-term implications of this altered physiology need to be followed-up.

Should we target obesity in advanced heart failure?

OPINION STATEMENT

Obesity is a risk factor for the development of heart failure (HF), but has been associated with improved survival in patients with established HF. Weight loss should clearly be recommended and supported for obese individuals without cardiac pathology to prevent cardiomyopathy development. Clinical recommendations at the other end of the obesity heart failure spectrum are also relatively clear. Morbidly obese individuals (BMI ≥ 40 kg/m(2)) aged <50 years with severely depressed systolic function and NYHA class III-IV symptoms should be considered for malabsorptive bariatric surgery at an experienced center. The goal is either improved systolic function and symptoms, or sufficient weight loss for heart transplant eligibility. Recommendations for patients falling between these extremes are more challenging. Overweight and mildly obese HF patients (25-35 kg/m(2)) may be somewhat protected from cardiac cachexia and weight loss is not expected to enhance survival, but may offer symptomatic benefits.

Pediatric cardiomyopathies: causes, epidemiology, clinical course, preventive strategies and therapies

Pediatric cardiomyopathies, which are rare but serious disorders of the muscles of the heart, affect at least one in every 100,000 children in the USA. Approximately 40% of children with symptomatic cardiomyopathy undergo heart transplantation or die from cardiac complications within 2 years. However, a significant number of children suffering from cardiomyopathy are surviving into adulthood, making it an important chronic illness for both pediatric and adult clinicians to understand. The natural history, risk factors, prevalence and incidence of this pediatric condition were not fully understood before the 1990s. Questions regarding optimal diagnostic, prognostic and treatment methods remain. Children require long-term follow-up into adulthood in order to identify the factors associated with best clinical practice including diagnostic approaches, as well as optimal treatment approaches. In this article, we comprehensively review current research on various presentations of this disease, along with current knowledge about their causes, treatments and clinical outcomes.

Impact of diet and exercise training-induced weight loss on myocardial mechanics in severely obese adolescents

OBJECTIVE

Recent findings indicated silent incipient myocardial dysfunction in juvenile obesity despite normal global cardiac function. The present study investigated whether lifestyle intervention is able to favorably impact these obesity-related myocardial abnormalities and whether improvements are related to changes in insulin resistance and cardiac remodeling.

DESIGN AND METHODS

Twenty-eight severe obese adolescents (OB) participated in a 9 month lifestyle intervention program (LIP) based on aerobic exercise and diet. Twenty healthy adolescents (CG) served as controls. Conventional echocardiography and myocardial mechanics were obtained at baseline and follow-up along with insulin resistance.

RESULTS

Insulin sensitivity improved (P < 0.001) and body weight decreased (P < 0.001) consecutive to LIP. At baseline, OB had depressed longitudinal (L) strain (CG: -18.3 ± 2.6, OB: -14.2 ± 3.6%, P < 0.001) and enhanced twist compared to controls. The LIP in OB restored L strain to normal values (-16.9 ± 3.5%, NS), whereas it did not affect twist mechanics. From stepwise multiple regression analysis, only baseline L strain and changes in BMI Z-score (r(2) -adjusted = 0.49, P < 0.001) emerged as independent predictors of L strain changes.

CONCLUSIONS

Juvenile obesity is associated with myocardial mechanic abnormalities that can be partly corrected by lifestyle intervention. Restoration of longitudinal myocardial function occurs in the absence of left ventricular remodeling changes and is not associated with insulin resistance improvements.

Early subclinical left-ventricular dysfunction in obese nonhypertensive children: a tissue Doppler imaging study

A direct effect of obesity on myocardial function has not been not well established. Our aim was to investigate the effect of body mass index (BMI) and homeostatic model assessment of insulin resistance (HOMA-IR) on left-ventricular (LV) myocardial function in normotensive overweight and obese children by tissue Doppler imaging (TDI). We calculated the mitral annular displacement index (DI) and myocardial performance index (MPI) using TDI indices of systolic and diastolic LV function. In this hospital-based, prospective cross-sectional study, we studied 60 obese (mean age 13.2 ± 2.0 years) and 50 normal children. Subjects were divided into three groups: group 1 (BMI < 25, n = 50, control), group 2 (BMI 25-29.9 kg/m(2), n = 30, overweight), and group 3 (BMI ≥ 30 kg/m(2), n = 30, morbidly obese). Standard echocardiography showed increased LV diameters and LV mass/index and preserved ejection fraction in obese children. By TDI, LV systolic and diastolic function showed that peak late myocardial velocity (Em = 15.4 ± 2 cm/s), peak early myocardial velocity (Am = 8.7 ± 1.3 cm/s), Em/Am ratio (1.8 ± 0.3), isovolumetric relaxation time (IVRT = 59.2 ± 8.2 ms), MPI (0.39 ± 0.03), and DI (25.5 ± 3.2 %) of the lateral mitral annulus in the obese subgroups were significantly different from those of control subjects (18.2 ± 1.2 cm/sn, 6.9 ± 0.6 cm/sn, 2.6 ± 0.2, 51.2 ± 9.6 ms, 0.34 ± 0.03, and 33.13 ± 5.0 %, respectively; p < 0.001). These structural and functional abnormalities were significantly related to BMI. There were positive correlations between HOMA-IR, septal MPI, and LV mass. DI and MPI data indicated impaired subclinical LV function in all grades of isolated obesity at a preclinical stage. Insulin resistance and BMI correlated significantly with indices of LV function.

Association of cardiac changes with serum adiponectin and resistin levels in obese and overweight children

OBJECTIVES

To investigate serum adiponectin and resistin levels in childhood obesity and their relationship with cardiac changes and insulin resistance.

METHODS

Seventy-one obese and 24 overweight children and 40 healthy children and adolescents were selected for the study. Height and weight measurements, BMI values and BMI SD score values were obtained for each individual. After blood pressure measurement, left ventricular wall thickness, left ventricular mass, stroke volume, cardiac output, systolic and diastolic functions of the left ventricle were measured using an M-mode, two dimensional color-coded echocardiography device. Blood samples of the individuals were obtained for fasting blood sugar, total blood cholesterol, triglyceride, low-density lipoprotein (LDL) cholesterol, very low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, insulin, C-peptide, adiponectin and resistin values.

RESULTS

Cholesterol and LDL values, homeostasis model assessment of insulin resistance, fasting insulin and fasting C-peptide values of the obese and overweight groups were higher (P<0.01). Adiponectin level (P<0.001) and resistin level (P<0.05) of the obese and overweight groups were lower than those of the control group (P<0.05). Echocardiographic evaluation showed diastolic dysfunction in addition to increased left ventricular wall thickness and left ventricle mass values in the obese and overweight children. We also detected a significant positive correlation among left ventricular mass, interventricular septum systolic diameter and resistin in obese children. Among the factors, resistin level was determined as an independent predictor of left ventricular mass in obese children.

CONCLUSION

In this study, even in asymptomatic obese and overweight children, cardiac structural and functional changes, such as increased left ventricular mass and diastolic dysfunction, were demonstrated. Although decreased adiponectin level was not related to cardiac changes, it was shown that decreased serum resistin levels in the obese cases lead to left ventricle hypertrophy.

Two-dimensional strain and twist by vector velocity imaging in adolescents with severe obesity

The prevalence of severe obesity is increasing worldwide in adolescents. Whether it is associated with functional myocardial abnormalities remains largely unknown, potentially because of its frequent association with other cardiovascular risk factors and also use of insensitive techniques to detect subclinical changes in myocardial function. We used 2D vector velocity imaging (VVI) to investigate early changes in left ventricular (LV) myocardial function in youths with isolated severe obesity. Thirty-seven asymptomatic severely obese adolescents free of diabetes and hypertension, and 24 lean controls were enrolled. LV longitudinal, basal, and apical circumferential strain, strain rate (SR), rotations, and LV twist were measured. Obese adolescents had greater LV mass and reduced systolic and early diastolic tissue Doppler imaging (TDI) velocities than lean counterparts. L strain (-24%) and systolic and early diastolic SR were also diminished in the obese, whereas no intergroup differences existed for the circumferential deformation indexes. LV twist was more pronounced in the obese (+1.7°, P < 0.01) on account of greater apical rotation only (4.1 ± 0.9 vs. 5.2 ± 1.2°, P < 0.01), potentially compensating for the loss in longitudinal function. Systolic-diastolic coupling, an important component of early filling and diastolic function, was maintained with severe obesity. No intergroup differences were reported regarding time to peak values for all VVI indexes highlighting that dynamics of strain and twist/untwist along the cardiac cycle was preserved with severe obesity. Isolated severe obesity in adolescents, at a preclinical stage, is associated with changes in myocardial deformation and torsional mechanics that could be in part related to alterations in relaxation and contractility properties of subendocardial fibers.

Cardiovascular disease in children and adolescents with diabetes: where are we, and where are we going?

The increasing prevalence of type 1 and type 2 diabetes mellitus combined with advancement in early detection of cardiovascular disease (CVD) has placed CVD as a significant concern for preventative pediatric medicine. The public health burden of type 2 diabetes is predicted to parallel increasing obesity in children with a projected increase of early CVD in adulthood. In this article, we review practice guidelines for cardiovascular health in children and adolescents with diabetes and data on which they are based. We then focus on imaging modalities that are promising tools to expand our understanding of the cardiovascular risk imposed on youths with diabetes.

Body fat, abdominal fat, and body fat distribution is related to left atrial diameter in young children

In adults, the size of the left atria (LA) has important prognostic information. In obese adults, adolescents and children enlargement of LA have been observed. This has not been investigated on a population-based level in young children. We therefore assessed if total body fat mass (TBF), abdominal fat, and body fat distribution were related to LA diameter. Cross-sectional study of 244 children (boys = 137 and girls n = 107) aged 8-11 years, recruited from an urban population-based cohort. Dual-energy X-ray absorptiometry (DXA) measured total lean body mass, TBF, and abdominal fat mass (AFM). Body fat was also calculated as a percentage of body mass (BF%). Body fat distribution (AFM/TBF) was calculated. Echocardiography was performed with two-dimensional guided M-mode. LA diameter was measured and left ventricular mass (LVM) was calculated. Systolic blood pressure and diastolic blood pressure were measured and maturity assessed according to Tanner. There were significant (P < 0.05) univariate correlations for all children between TBF (r = 0.40), BF% (r = 0.32), AFM (r = 0.41), and AFM/TBF (r = 0.41) vs. LA diameter. Multiple regression analyses with the inclusion of possible confounders such as lean body mass, blood pressure, gender, age, and Tanner stage revealed that TBF, AFM, and AFM/TBF were all independently related to LA diameter. Differences in the different body fat measurements explained 6-9% of the variance in LA size. These results demonstrated that both total body fat, AFM, and body fat distribution are already at a young age negatively and independently associated to LA diameter.

Newer Doppler echocardiography techniques in assessment of heart function in obese patients

Obesity is one of the major health problems of modem society. The prevalence of this condition has increased at an alarming rate, especially the most severe form (body mass index >40 kg/m2). The cardiovascular problems that generally accompany obesity are the focus of a large number of studies. Conventional echogram and more current modalities, such as tissue Doppler, strain and strain rate are valuable tools for the detection of subclinical dysfunction and the early diagnosis and treatment of patients.

Early myocardial deformation changes associated to isolated obesity: a study based on 3D-wall motion tracking analysis

Obesity is considered as a strong risk factor for cardiovascular morbidity and mortality. 3D-wall motion tracking echocardiography (3D-WMT) provides information regarding different parameters of left ventricular (LV) myocardial deformation. Our aim was to assess the presence of early myocardial deformation abnormalities in nonselected obese children free from other cardiovascular risk factors. Thirty consecutive nonselected obese children and 42 healthy volunteer children were enrolled. None of them had any cardiovascular risk factor. Every subject underwent a 2D-echo examination and a 3D-WMT study. Mean age was 13.9 ± 2.56 and 13.25 ± 2.68 years in the nonobese and obese groups, respectively (59.7% and 40.3% male). Statistically significant differences were found for: interventricular septum thickness, LV posterior wall thickness, LV end-diastolic volume, LV end-systolic volume, left atrium volume, LV mass, and lateral annulus peak velocity. Regarding the results obtained by 3D-WMT assessment, all the evaluated parameters were statistically significantly different between the two groups. When the influence of obesity on the different echocardiographic variables was evaluated by means of multivariate logistic regression analysis, the strongest relationship with obesity was found for LV average circumferential strain (β-coefficient: 0.74; r(2): 0.55; P: 0.003). Thus, obesity cardiomyopathy is associated not only with structural cardiac changes, but also with myocardial deformation changes. Furthermore, this association occurs as early as in the childhood and it is independent from any other cardiovascular risk factor. The most related parameter to obesity is LV circumferential strain.

Cardiovascular dysfunction in obesity and new diagnostic imaging techniques: the role of noninvasive image methods

Obesity is a major public health problem affecting adults and children in both developed and developing countries. This condition often leads to metabolic syndrome, which increases the risk of cardiovascular disease. A large number of studies have been carried out to understand the pathogenesis of cardiovascular dysfunction in obese patients. Endothelial dysfunction plays a key role in the progression of atherosclerosis and the development of coronary artery disease, hypertension and congestive heart failure. Noninvasive methods in the field of cardiovascular imaging, such as measuring intima-media thickness, flow-mediated dilatation, tissue Doppler, and strain, and strain rate, constitute new tools for the early detection of cardiac and vascular dysfunction. These techniques will certainly enable a better evaluation of initial cardiovascular injury and allow the correct, timely management of obese patients. The present review summarizes the main aspects of cardiovascular dysfunction in obesity and discusses the application of recent noninvasive imaging methods for the early detection of cardiovascular alterations.

Strain imaging in morbid obesity: insights into subclinical ventricular dysfunction

BACKGROUND

Obesity has become an important health problem throughout the world. Early detection of cardiovascular abnormalities may be useful in the future for patient management. This study aimed to identify subclinical ventricular dysfunction in obese patients.

HYPOTHESIS

Morbid obesity is associated with ventricular dysfunction.

METHODS

Doppler echocardiogram was performed in 92 morbidly obese and in 31 healthy controls. Conventional echocardiography and tissue Doppler-based strain imaging were used to analyze ventricular function. Intra- and interobserver strain imaging variabilities were tested on 15 randomly selected cases.

RESULTS

Left ventricular (LV) global strain (22.5% ± 3.5 vs 24.4% ± 2.5, P<0.005) and right ventricular (RV) strain (25.8% ± 5.2 vs 28.2% ± 5.2, P<0.029) were lower in obese patients when compared with healthy controls. Echocardiographic parameters of diastolic function were also different from controls. LV strain correlated with LV mass, E/e' ratio, left atrial volume, and RV strain. At multivariate analysis, morbid obesity remained a significant determinant of global LV strain, independently of associated comorbidities.

CONCLUSIONS

These findings suggest that incipient biventricular dysfunction is present in morbidly obese patients when new echocardiographic indices are used to investigate ventricular function. In addition, strain imaging may provide a more accurate assessment of the ventricular function in obese patients.

Early cardiac abnormalities and serum N-terminal pro B-type natriuretic peptide levels in obese children

OBJECTIVE

The aim of this study was to evaluate early cardiac abnormalities in obese children by the conventional echocardiography and to verify whether N-terminal pro B-type natriuretic peptide (NT-proBNP) differ between obese and healthy children.

METHODS

We started this study with 68 obese children and 35 healthy controls matched for age and sex. Body mass index (BMI) was calculated. Children with a BMI > or = 95th percentile were considered obese. Thirty children in the obese group were also diagnosed with metabolic syndrome, according to the International Diabetes Federation criteria. Standard echocardiographic study was performed on each patient and control subject. Diastolic filling parameters were evaluated using pulsed-wave tissue Doppler method. Blood samples were taken at 8 a.m. to study blood biochemistry tests, including insulin, lipids, glucose, and NT-proBNP. Serum NT-proBNP levels were measured by a solid-phase, enzyme-labeled chemiluminescent immunometric assay. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Children with HOMA-IR > 3.16 were considered insulin-resistant.

RESULTS

There were diastolic filling abnormalities in obese children, as shown by a decreased mitral valve early filling (E) wave/late filling (A) ratio and a prolongation in E-wave deceleration time. The levels of NT-proBNP were not statistically different among the groups. The levels of NT-proBNP were not different between obese children with and without metabolic syndrome, those with and without hypertension, and those with and without insulin resistance, respectively.

CONCLUSION

Although there were diastolic filling abnormalities in obese children, their NT-proBNP levels were not different from healthy controls. It seems that there is no diagnostic value in NT-proBNP levels between obese children and healthy controls.

Right ventricular function in children with bronchial asthma: a tissue Doppler echocardiographic study

Asthma is the most common cause of respiratory disability among children. Patients with severe bronchial asthma can experience cor pulmonale later in life, but little is known about the function of the right ventricle early in the disease. This study aimed to investigate the right ventricular function in children with bronchial asthma as detected by tissue Doppler echocardiography. This case-control study compared 60 asthmatic children ages 5 to 15 years between attacks (study group) with 60 apparently healthy children (control group). All the children were subjected to full history-taking, complete physical examination, measurement of peak expiratory flow rate (PEFR), chest x-ray, electrocardiography (ECG), echocardiographic examination, and both conventional and tissue Doppler study. The results of the tissue Doppler study examining the right ventricular diastolic function showed that peak E' velocity (10.08 ± 2.8 cm/s), peak A' velocity (5.7 ± 2.5 cm/s), E'/A' ratio (1.77 ± 0.58 m/s), and isovolumetric relaxation time (IVRT) of the lateral tricuspid annulus (138.9 ± 30.7 m/s) among the asthmatic patients differed significantly from those among the control subjects (12.4 ± 2.3, 7.8 ± 2.1 cm/s; 1.58 ± 0.32, and 91.1 ± 32.6 m/s, respectively). In addition, the E' velocity and IVRT of the lateral tricuspid annulus were significantly different among the mild, moderate, and severe cases (P < 0.001). It is concluded that although the clinical and conventional echocardiographic findings of the asthmatic children were apparently normal, the tissue Doppler echocardiographic study showed right ventricular dysfunction that is positively correlated with the severity of asthma. These findings signify the diagnostic value of tissue Doppler echocardiography for the early detection and monitoring of such deleterious effects among asthmatic patients.

Importance of plasma N-terminal pro B-type natriuretic peptide, epicardial adipose tissue, and carotid intima-media thicknesses in asymptomatic obese children

This study aimed to analyze the variations of N-terminal pro B-type natriuretic peptide, epicardial adipose tissue thickness, and carotid intima-media thickness in childhood obesity. The study participants consisted of 50 obese children in the study group and 20 nonobese children referred for evaluation of murmurs who proved to have an innocent murmur and were used as control subjects. All the subjects underwent transthoracic echocardiographic examination for determination of left ventricular systolic function and mass index, myocardial tissue rates, and myocardial performance index. Epicardial adipose tissue thickness and carotid intima-media thickness also were measured during echocardiography. Serum N-terminal pro B-type natriuretic peptide levels were measured at the time of evaluation. The left ventricle mass index was 40.21 + or - 10.42 g/m(2) in the obese group and 34.44 + or - 4.51 g/m(2) in the control group (p > 0.05). The serum N-terminal pro B-type natriuretic peptide level was 109.25 + or - 48.53 pg/ml in the study group and 51.96 + or - 22.36 pg/ml and in the control group (p = 0.001). The epicardial adipose tissue thickness was 5.57 + or - 1.45 mm in the study group and 2.98 + or - 0.41 mm in the control group (p = 0.001), and the respective carotid intima-media thicknesses were 0.079 + or - 0.019 cm and 0.049 + or - 0.012 cm (p = 0.001). The left ventricular systolic and diastolic functions showed no statistically significant correlations with N-terminal pro B-type natriuretic peptide levels, carotid intima-media thickness, or epicardial adipose tissue thickness values. The results show that measurement of serum N-terminal pro B-type natriuretic peptide level, carotid intima-media thickness, and epicardial adipose tissue thickness in asymptomatic obese children is not needed.

Echocardiographic measurement of epicardial adipose tissue in obese children

The echocardiographic measurement of epicardial adipose tissue (EAT) has been suggested as an easy method for evaluation of the visceral adipose tissue and its related cardiovascular risks in adults. However, a direct effect of obesity on cardiac function is not well established, and echocardiographic EAT thickness has not been studied in children. The aims of this study were to evaluate cardiac function and echocardiographic EAT thickness and to correlate EAT with the other echocardiographic findings in obese children. The study population included 106 obese and 62 lean children. Echocardiographic indexes of systolic and diastolic function were obtained. We measured EAT thickness on the free wall of the right ventricle from parasternal long-axis views. The septal and posterior wall thicknesses, relative wall thickness, left atrial diameter, and left ventricular mass were increased (p = 0.001) in obese children. However, systolic and diastolic functions of the left ventricle were normal in the patients. The obese children had a significantly thicker EAT (p = 0.001) compared to the lean subjects. EAT thickness correlated significantly with body mass index (r = 0.50, p = 0.001), left atrial diameter (r = 0.37, p = 0.001), and left ventricular mass (r = 0.33, p = 0.001). In conclusion, the present study demonstrates a close relationship between EAT thickness and obesity in children. Assessment of EAT thickness in routine echocardiographic examinations might be used as a feasible and reliable method for the evaluation of obesity and its related cardiovascular risks during childhood.

Early markers of cardiovascular dysfunction in young girls affected by Cushing's syndrome before and after successful cure

BACKGROUND

even after successful surgical cure, Cushing's Syndrome (CS) may induce cardiovascular (CV) diseases including hypertension, or elicit onset of CV risk factors, such as obesity.

OBJECTIVES

to evaluate some early markers of CV dysfunction in adolescent girls before and after successful surgical cure of CS; to compare after surgery data with those of a control group (C) of healthy young girls.

METHODS

23 girls affected by CS were enrolled (range: 11-17 years; mean: 14.3 +/- 1.7 years). Epicardial fat thickness (EFT), intima-media thickness (IMT), N-terminal pro B-type natriuretic peptide (NT-proBNP) were assessed; transthoracic echocardiogram coupled with Tissue Doppler imaging (TDI) was performed. RESULTS (CS before surgery vs. CS after surgery): EFT (p < 0.05). (CS after surgery vs. C): EFT (p = 0.0001); IMT (p = 0.0001); NT-proBNP (p = 0.0001). TDI: isovolumetric relaxation time (p = 0.001); isovolumetric contraction time (p = 0.001); myocardial performance index (p = 0.001). Significant correlations: NT-proBNP with IRT (r = 0.45, p = 0.026 ), ICT (r = 0.47, p = 0.028), and myocardial performance index (r = 0.51, p = 0.0032).

CONCLUSIONS

important structural and functional modifications of heart and vessels are present in young female CS despite successful surgical cure, even in paediatric age. It underlines their significantly higher cardiovascular risk. Our findings confirm that EFT, IMT, NT-proBNP and TDI diastolic parameters, not previously tested in paediatric CS, are early markers of cardiovascular dysfunction. Because of its relationship with TDI, the assessment of NT-proBNP proves to be the best marker in detecting a cardiovascular dysfunction in this specific population.

The effect of low-carbohydrate diet on left ventricular diastolic function in obese children

BACKGROUND

This study was conducted to evaluate left ventricle (LV) functions using conventional and tissue Doppler imaging in childhood obesity and to identify the effects of diet on LV diastolic functions.

METHODS

Conventional and tissue Doppler echocardiographic measurements were compared in 34 obese children and 24 age- and gender-matched lean controls. Fasting plasma glucose, insulin and homeostatic model assessment of insulin resistance levels were also obtained. Thirty-one of the obese children were subjected to a low-carbohydrate diet and their follow-up measurements were obtained after 6 months.

RESULTS

Left atrial diameter, LV mass and LV mass index were higher in obese children than in lean controls. Lateral mitral myocardial early diastolic (E(m)) and peak E(m)/myocardial late diastolic (A(m)) were lower, and mitral E/E(m) and lateral mitral myocardial isovolumetric relaxation time were higher in obese subjects than in lean controls. Insulin and homeostatic model assessment of insulin resistance levels were higher in obese patients and decreased significantly after diet. After diet therapy, lateral mitral E(m) and peak E(m)/A(m), were increased, mitral E/E(m) and myocardial isovolumetric relaxation time were decreased.

CONCLUSIONS

Obesity predisposes children to increased preload reserve, left ventricular subclinical diastolic dysfunction and deterioration in diastolic filling. Weight reduction with a low-carbohydrate diet seems to be associated with significant improvement in LV diastolic function and a decrease in diastolic filling, as well as causing reversal in insulin resistance seen in obese children.

Early echocardiography abnormalities in obese children and adolescent and reversibility of these abnormalities after significant weight reduction

BACKGROUND

Obesity is becoming an epidemic threat for the individual and society. The increasing prevalence of overweight children and adolescents is likely to have a great impact on the future cardiovascular health of these subjects. Obesity is a strong risk factor for cardiovascular morbidity and mortality. Cardiac abnormalities of obese children and adolescents include the echocardiographically revealed early and preclinical LV or septal hypertrophy, and left or right ventricular dysfunction. Most of these abnormalities, which are usually more pronounced in patients with morbid obesity, can be partially reversed after weight reduction.

AIM OF THE STUDY

Evaluate early echocardiography changes in obese children and whether these cardiac abnormalities reverse with significant weight reduction in children and adolescents or not.

METHODS

We started this study by 50 obese children and adolescents and 30 non obese controls matched for age and sex. BMI was calculated. Complete echocardiographic study was performed on each patient and control subject. Hematological and biochemical variables were determined in the obese subjects from fasting blood samples and included glucose, total cholesterol, triglycerides (TG), HDL cholesterol and LDL cholesterol. All our patients' strict dietetic regime with exercises for 6 months. After 6 months full examination, including all measurements and echocardiography and laboratory investigations were done again.

RESULTS

Obese children has abnormalities of left ventricle structure and function (consisting of increased left ventricular wall dimensions and mass and alteration of diastolic function) that can be detected by echocardiography. Furthermore, (parameters of lipid metabolism) were found to be independent predictors of adverse LV remodeling and of diastolic dysfunction. As well as this study provides evidence that abnormalities of left ventricular wall dimension and mass in obese children and adolescents can improve with significant weight reduction.

CONCLUSION

This study has demonstrated that young, obese children and adolescents have early significant changes in left ventricular wall dimensions and early diastolic filling compared with non obese and this changes are reversible with weight reduction.

Cardiac function during exercise in obese prepubertal boys: effect of degree of obesity

The purpose of the study was to evaluate the dynamics of diastolic and systolic function from rest to maximal exercise using conventional echocardiography and tissue Doppler imaging (TDI) in obese prepubertal boys compared to age-matched lean controls. Eighteen obese (10 with first degree obesity and 8 with second degree obesity according to French curves, BMI: 23.3+/-1.8 and 29.0+/-2.0 kg/m2, respectively) and 17 lean controls (BMI=17.6+/-0.6 kg/m2, P<0.001), aged 10-12 years were recruited. After resting echocardiography, all children performed a maximal exercise test. Regional diastolic and systolic myocardial velocities were acquired at rest and each workload. Stroke volume and cardiac output were calculated. At rest, obese boys had greater left ventricular (LV) diameters and LV mass. Boys in the first degree group showed no diastolic or systolic dysfunction, whereas boys with second degree obesity showed subtle diastolic dysfunction. During exercise, both obese groups showed greater stroke volume and cardiac output. First degree obese boys exhibited greater systolic and diastolic tissue Doppler velocities than controls, whereas second degree obese boys had lower diastolic tissue velocities irrespective of exercise intensity and lower fractional shortening at high exercise intensities than controls. In conclusion, no impairment in diastolic or systolic function is noticed in prepubertal boys with first degree of obesity. Enhanced regional myocardial function response to exercise was also demonstrated in this population, suggesting adaptive compensatory cardiac changes in mild obesity. However, when obesity becomes more severe, impaired global and regional cardiac function at rest and during exercise can be observed.

Right ventricular subclinical diastolic dysfunction in obese children: the effect of weight reduction with a low-carbohydrate diet

This study aimed primarily to identify whether childhood obesity leads to right ventricular (RV) subclinical diastolic dysfunction or not. It also aimed to examine the effect of weight reduction on right ventricular function. Standard and tissue Doppler echocardiography was performed for 28 overweight (body mass index [BMI], 25-30 kg/m(2)) and 34 obese (BMI, > or = 30 kg/m(2)) children and for 29 age- and sex-matched lean referents (BMI, 17-25 kg/m(2)). Levels of plasma lipids, fasting glucose, insulin, and homeostatic model assessment of insulin resistance (HOMA-IR) were obtained for all the participants. For 6 months, 30 obese children were given a low-carbohydrate diet and then reevaluated by echocardiography. Conventional echocardiographic parameters all were similar for obese, overweight, and lean control children. The tricuspid free-wall isovolumetric relaxation time (IVRT), tricuspid lateral annular early diastolic velocity (e'), ratio of early-to-late diastolic velocity (e'/a'), and tricuspid lateral annular IVRT differed significantly between the overweight and control children. The RV tissue Doppler parameters were found to be similar between the preobese and control children. The IVRT of the RV free wall and lateral tricuspid annulus was significantly decreased, and the e'/a' of the lateral tricuspid annulus was significantly increased after the diet. In conclusion, obesity is associated with subclinical RV diastolic dysfunction in pediatric patients. Weight reduction with a low-carbohydrate diet may reverse the effects of obesity on RV diastolic function.

Early cardiac abnormalities in obese children: importance of obesity per se versus associated cardiovascular risk factors

We investigated whether obese children and adolescents have early echocardiographic signs of subclinical cardiac dysfunction and evaluated the respective influence of obesity per se versus parameters of carbohydrate and lipid metabolism that are frequently abnormal in obese subjects. The role of tissue Doppler imaging as a screening tool for these abnormalities was explored. Blood pressure and echocardiographic parameters, including tissue Doppler measurements of the septal mitral annulus were evaluated in 49 obese children and adolescents and 45 age and sex matched controls. The respective influence of obesity versus parameters of carbohydrate and lipid metabolism was examined with linear regression analysis. Obese subjects showed significantly larger left ventricular wall dimensions (posterior wall, septum, and left ventricular mass index) and signs of early diastolic filling abnormalities on conventional and tissue Doppler echocardiography compared with nonobese subjects. Multiple regression analysis showed that mainly BMI-SD scores and/or body surface area explained significant proportions of the variance of the early cardiac abnormalities. In conclusion, young, obese children and adolescents have significant changes in left ventricular wall dimensions and early diastolic filling compared with nonobese subjects. Obesity per se and not the parameters of carbohydrate and lipid metabolism predicted the early cardiac abnormalities.

Obesity is a common comorbidity in children with congenital and acquired heart disease

OBJECTIVES

Obesity may pose additional cardiovascular risk to children with acquired and congenital heart disease. Many children with heart disease are sedentary as a result of physician-, parent-, and/or self-imposed restrictions. The aim of this study was to evaluate the impact of the epidemic of obesity on children with heart disease.

PATIENTS AND METHODS

A cross-sectional review was performed of children evaluated in 2004 at 2 cardiology outpatient clinics. Differences in the prevalence of obese (BMI > or = 95%) and overweight (BMI 85%-95%) children were compared with national data and healthy control subjects. Dictated letters were reviewed to determine whether obesity was discussed with referring practitioners.

RESULTS

Of 2921 patients assessed, 1523 had heart disease. Diagnostic subgroups included "mild" heart disease (n = 401), arrhythmia (n = 447), biventricular repair (n = 511), univentricular palliation (Fontan; n = 108), and heart transplantation (n = 56). More than 25% of the patients with heart disease were obese or overweight; the prevalence of obese and overweight children was significantly lower only in the Fontan group (15.9%). Pediatric cardiologists failed to document obesity or weight counseling in the majority of clinic letters.

CONCLUSIONS

Obesity is common in children with congenital and acquired heart disease. Pediatric cardiologists demonstrate inadequate communication regarding this problem to referring practitioners. Healthy-lifestyle counseling and routine exercise in children with heart disease may be underemphasized.

Myocardial velocity, strain, and strain rate abnormalities in healthy obese children

Childhood obesity is a major health care issue in the United States. This epidemic has important cardiovascular implications. Newer imaging modalities in obese adults have demonstrated abnormal systolic and diastolic cardiac function. The authors proposed to determine whether these abnormalities are present in obese children. A total of 168 children were identified from our echocardiographic database. Body mass index for age was calculated. Echocardiographic clips were analyzed using imaging technology to determine myocardial motion, strain, and strain rate. Patients at risk for obesity and those meeting criteria for obesity had increased late diastolic myocardial motion compared with normal-weight children. Obese patients had decreased systolic strain compared with normal-weight children. As with adults, obese children have significant differences in diastolic function and strain. These abnormalities may be subtle markers for the emergence of future cardiac disease.

Diastolic filling abnormalities in children with essential hypertension

OBJECTIVE

To evaluate whether essential hypertension impacts diastolic function in children.

STUDY DESIGN

In this cross-sectional study, patients with essential hypertension (n = 50) were compared with a normotensive group (n = 53). Echocardiographic assessment of diastolic function included measures derived from transmitral, color M-mode, and tissue Doppler interrogation. Cardiac dimensions, wall thickness, geometry, and systolic function were also assessed. Multiple linear regression analysis was performed to identify predictors of altered diastolic function.

RESULTS

Diastolic filling abnormalities were found in 36% of the children with blood pressure elevation. Those subjects with concentric hypertrophy were more significantly affected. Abnormalities in indices reflective of left ventricular (LV) relaxation occurred more commonly (39%) than those of LV compliance (33%). Elevated indexed LV mass was found to be the most significant independent predictor of diastolic filling abnormalities.

CONCLUSIONS

LV diastolic filling abnormalities were found in one-third of the pediatric subjects with essential hypertension. Whether these changes represent an adaptive or maladaptive response requires further study.

Echocardiographic measures of diastolic function in pediatric heart disease

PURPOSE OF REVIEW

The past year has seen a continued evolution in the echocardiographic assessment of diastolic function in children. This paper reviews published studies from the past year that have helped characterize diastolic function using echocardiography in children.

RECENT FINDINGS

Characterization of diastolic function using Doppler and Doppler tissue imaging in the normal infant and child was a primary focus of pediatric echocardiographic investigation. These technologies appear to hold significant promise as tools to improve understanding of diastolic function in the normal child as the heart matures. Diastolic function in children with congenital heart disease has also been better characterized using these tools, specifically in patients with atrial septal defects, tetralogy of Fallot, single ventricle physiology, and following cardiac transplantation. Finally, diastolic function in acquired heart disease or with systemic disease in the child has been evaluated using echocardiography, with recent reports describing findings in children with dilated cardiomyopathy, chronic renal disease, obesity, type I diabetes, juvenile rheumatoid arthritis, obstructive sleep apnea, and after anthracycline exposure for childhood cancer.

SUMMARY

Pediatric echocardiography has clearly become the primary tool for describing and characterizing diastolic function in infants and children both with and without heart disease. It is becoming an important noninvasive diastolic monitoring tool that allows serial assessment of pathologic diastolic disease in both primary myocardial and systemic disease states.

Impact of obesity on diastolic function in subjects < or = 16 years of age

The aim of this study was to investigate the impact of obesity on diastolic function in children and adolescents. Echocardiographic measurements were compared in 28 obese subjects (14 males, 14 females) and 15 age- and gender-matched lean controls (8 males, 7 females). Two-dimensional ultrasound imaging, M-mode imaging, and pulse-wave conventional and tissue Doppler measurements were used to assess cardiac structure and function at rest. No differences were evident between lean and obese subjects in age (13.3 +/- 0.5 vs 12.4 +/- 0.4 years), height (163 +/- 4 vs 159 +/- 2 cm), or systolic blood pressure (119 +/- 3 vs 123 +/- 2 mm Hg). Body mass (54.6 +/- 4.0 vs 85.8 +/- 3.6 kg, p < 0.0001) and body mass index (20.5 +/- 0.7 vs 33.3 +/- 1.0 kg/m2, p < 0.00001) were significantly greater in the obese subjects, whereas measurements of wall thickness (interventricular septal wall 0.86 +/- 0.04 vs 0.89 +/- 0.02 cm, posterior wall 0.83 +/- 0.04 vs 0.91 +/- 0.02 cm) and fractional shortening (38.6 +/- 1.2% vs 38.8 +/- 1.2%) did not significantly differ. The E/E' ratio (6.86 +/- 0.20 vs 8.30 +/- 0.32, p < 0.01), E' (13.93 +/- 0.38 vs 12.29 +/- 0.44 cm/s, p < 0.05), the E'/A' ratio (2.49 +/- 0.17 vs 2.05 +/- 0.09, p < 0.05), and the deceleration time of early transmitral blood flow velocity (125.3 +/- 7.7 vs 154.5 +/- 6.8 ms, p < 0.01) were significantly different between the groups, suggesting reduced diastolic function in the obese subjects. In conclusion, these data suggest that indexes of diastolic function, including tissue Doppler measures, are significantly impaired in obese young subjects.

Left atrial diameters in overweight children with normal blood pressure

OBJECTIVE

To measure left atrial (LA) diameter in normotensive, overweight children and to determine the variables that independently influence LA diameters.

STUDY DESIGN

A cross-sectional study on 22 overweight children (age, 13.40 +/- 1.22 years) and 18 control children (age, 13.40 +/- 2.19 years) was performed. LA diameter, left ventricular (LV) geometry, and LV systolic/diastolic function were measured through echocardiography. Data were compared between the two groups. Multiple regression analysis, with LA diameter as dependent variable, was conducted.

RESULTS

In the overweight group, LV diastolic dimension, LV mass index, peak S, S/D ratio, Am, maximal LA diameter (34.1 mm vs 25.4 mm), middle LA diameter (26.9 mm vs 18.1 mm), and minimal LA diameter (22.5 mm vs 16.1 mm) were increased and Em/Am ratio was decreased. In multiple regression analysis, body mass index (R(2) = 0.7040, 0.7085, 0.7406 in respective maximal, middle, and minimal LA diameter) and systolic blood pressure (R(2) = 0.0540, 0.0477, 0.030 in respective maximal, middle, and minimal LA diameter) were significant independent correlates of all three measures of LA diameter.

CONCLUSIONS

LA diameter in normotensive overweight children is increased. Body mass index and systolic blood pressure were significant correlates of LA diameter.

Update on pediatric echocardiography

PURPOSE OF REVIEW

The past year was dominated by developments in echocardiographic assessment of myocardial function in children, and this paper reviews some of these major advancements in pediatric echocardiography as a guide to those interested in imaging of the pediatric heart and vascular system.

RECENT FINDINGS

Characterization of myocardial function using Doppler tissue imaging, both in the normal child and in the child with congenital or acquired heart disease, was a primary focus of pediatric echocardiographic investigation. Other new technologies, including integrated backscatter analysis and three-dimensional echocardiography, appear to hold significant promise as tools to improve myocardial assessment echocardiographically. Three-dimensional echocardiography also is developing into a powerful technique in fetal echocardiography, allowing rapid data acquisition and extensive image postprocessing with opportunities for both anatomic and functional assessment. Childhood fitness and diseases have a significant impact on the heart and vascular bed, and descriptions of echocardiographic findings in obese children, children engaged in athletic activities, children with renal disease, children who have undergone cardiac transplantation, and those with aortic valve disease were better characterized by investigations published over the past year.

SUMMARY

Pediatric echocardiography has clearly expanded from a diagnostic tool used to describe anatomic abnormalities associated with congenital heart disease to a noninvasive myocardial monitoring tool that allows serial assessment of the pathologic effects of both cardiac and noncardiac disease.