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

Left atrial remodeling in adolescents with obesity evaluated by speckle-tracking echocardiography

BACKGROUND AND AIMS

In adolescents with obesity, a left atrial (LA) enlargement has been reported. However, data regarding its function and its stiffness are missing. The aim of this study was to describe LA morphology and function, using speckle-tracking echocardiography (STE) and to explore their potential determinants in adolescents with obesity.

METHODS

Twenty-eight adolescent women with obesity (13.2 ± 1.4 yr) with an illness duration of 130 ± 27 months and 33 controls (14.1 ± 2.0 yr) underwent a resting echocardiography including an analysis of left ventricular (LV) and LA morphologies and strains. A fasting venous blood sample was performed to biochemical determinations including inflammation markers.

RESULTS

LA volume and stiffness index were increased in adolescents with obesity compared to controls. LA reservoir, conduit and booster pump functions were not different between groups. By stepwise forward multivariate regression analyses, systolic blood pressures, cardiac output and sedimentation rate were the independent determinants of LA volume (p < 0.0001, β-coefficient = 0.460) whereas only the body mass index was an independent determinant of LA stiffness (p = 0.003, β-coefficient = 0.413).

CONCLUSION

In adolescents with obesity, we observed a specific LA remodeling, including higher volume and lower stiffness, which could constitute early signs of an altered LV diastolic function.

Childhood Obesity and Congenital Heart Disease: A Lifelong Struggle

Congenital heart disease (CHD) affects approximately one in every one hundred infants worldwide, making it one of the most prevalent birth abnormalities globally. Despite advances in medical technology and treatment choices, CHD remains a significant health issue and necessitates specialized care throughout an individual's life. Childhood obesity has emerged as a novel global epidemic, becoming a major public health issue, particularly in individuals with lifelong conditions such as CHD. Obesity has profound effects on cardiac hemodynamics and morphology, emphasizing the importance of addressing obesity as a significant risk factor for cardiovascular health. Obesity-induced alterations in cardiac function can have significant implications for cardiovascular health and may contribute to the increased risk of heart-related complications in obese individuals. Moreover, while diastolic dysfunction may be less apparent in obese children compared to adults, certain parameters do indicate changes in early left ventricular relaxation, suggesting that obesity can cause cardiac dysfunction even in pediatric populations. As most children with CHD now survive into adulthood, there is also concern about environmental and behavioral health risk factors in this particular patient group. Addressing obesity in individuals with CHD is essential to optimize their cardiovascular health and overall quality of life. This review aims to succinctly present the data on the impact of obesity on CHD and to enhance awareness of this perilous association among patients, families, and healthcare providers.

Impact of BMI z-score on left ventricular mechanics in adolescent girls

Background

Adolescent weight disorders ranging from anorexia nervosa (AN) to obesity (OB) can impact the heart by causing opposite alterations in its morphology, suggesting a direct impact of body mass index (BMI) on the heart. Cardiac function is relatively preserved as assessed by standard echocardiography. However, few studies have used 2D speckle-tracking echocardiography (2D-STE), which can detect subtle alterations of left ventricular (LV) function by evaluating deformations. This study aimed to assess the link between the BMI z-score of adolescent girls and myocardial function.

Methods

Ninety-one adolescent girls comprising 26 AN patients (age 14.6 ± 1.9 years), 28 OB patients (age 13.2 ± 1.4 years), and 37 controls (age 14.0 ± 2.0 years) underwent 2D-STE to assess LV morphology and myocardial global and regional deformations.

Results

The BMI z-score of our population ranged from -4.6 to 5.2. LV morphological remodeling was significantly and positively correlated with the BMI z-score (R2 = 0.456, p < 0.0001 for LV mass). Global longitudinal strain (LS) and regional LS recorded at the mid and apical levels were significantly correlated with the BMI z-score (R2 = 0.196, p = 0.0001 and R2 = 0.274, p < 0.0001, respectively, for apical and medial LS). Circumferential strains and twisting mechanics were not correlated with the BMI z-score. Fibrinogen and systolic blood pressure were the main variables explaining the alteration of LS.

Conclusion

We observed that the BMI z-score had an impact on LV mechanics, especially on medial and apical LS. Neither circumferential nor twisting mechanics were altered by the BMI z-score in adolescent girls.

Cardiac Function After Cardiotoxic Treatments for Childhood Cancer-Left Ventricular Longitudinal Strain in Screening

Background: The majority of childhood cancer survivors (CCSs) have been exposed to cardiotoxic treatments and often present with modifiable cardiovascular risk factors. Our aim was to evaluate the value of left ventricular (LV) longitudinal strain for increasing the sensitivity of cardiac dysfunction detection among CCSs. Methods: We combined two national cohorts: neuroblastoma and other childhood cancer survivors treated with anthracyclines. The final data consisted of 90 long-term CCSs exposed to anthracyclines and/or high-dose chemotherapy with autologous stem cell rescue and followed up for > 5 years and their controls (n = 86). LV longitudinal strain was assessed with speckle tracking (Qlab) and LV ejection fraction (EF) by three-dimensional echocardiography (3DE). Results: Of the CCSs, 11% (10/90) had abnormal LV longitudinal strain (i.e., < -17.5%); of those, 70% (7/10) had normal 3DE LV EF. Multivariable linear model analysis demonstrated that follow-up time (p = 0.027), sex (p = 0.020), and BMI (p = 0.002) were significantly associated with LV longitudinal strain. Conversely, cardiac risk group, hypertension, age, cumulative anthracycline dose or exposure to chest radiation were not. Conclusion: LV longitudinal strain is a more sensitive method than LV EF for the detection of cardiac dysfunction among CCSs. Therefore, LV longitudinal strain should be added to the screening panel, especially for those with modifiable cardiovascular risk factors.

Myocardial Geometry and Dysfunction in Morbidly Obese Adolescents (BMI 35-40 kg/m2)

This study evaluated the preclinical effect of obesity on the ventricular remodeling in adolescents with morbid obesity, and determined if subjects labelled as metabolically healthy obesity (MHO) presented better heart index than those with metabolically unhealthy obesity (MUO). Prospective case-control research of 45 adolescents (14-year-old) with morbid obesity and 25 normal weight adolescents' gender- and age-matched with Tanner stage 4-5. Left ventricle (LV) was evaluated by conventional Doppler echocardiography, tissue Doppler imaging and two-dimensional speckle tracking echocardiography. Compared to normal-weight subjects, adolescents with morbid obesity presented a high percentage of pathological LV geometry (87%; p<0.01), and systolic and diastolic dysfunctions only detected by E/A ratio (2.0 vs 1.7, p<0.01), global longitudinal strain (-21.0% vs -16.5%, p<0.01), and early diastolic strain rate (3.2 vs 2.2, p<0.01). A correlation was found between impaired cardiac index and body mass index (BMI), high blood pressure, hyperglycemia, low HDL-cholesterol and hypertriglyceridemia. BMI and HDL-cholesterol were the most significant independent variables. No significant differences were found in structural and functional cardiac index when MHO and MUO subjects were compared (global longitudinal strain: -17.0% vs -16.4%, p0.79). Morbidly obese adolescents have an abnormal LV geometry, closely related to BMI, and systolic and diastolic LV dysfunctions. Adolescents labelled as MHO, despite exhibiting better BMI and insulin-resistance values, present the same pathological heart changes as MUO.

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.

Pediatric Metabolic and Bariatric Surgery

Childhood obesity can lead to comorbidities that cause significant decrease in health-related quality of life and early mortality. Recognition of obesity as a disease of polygenic etiology can help deter implicit bias. Current guidelines for treating severe obesity in children recommend referral to a multidisciplinary treatment center that offers metabolic and bariatric surgery at any age when a child develops a body mass index that is greater than 120% of the 95th percentile. Obesity medications and lifestyle counseling about diet and exercise are not adequate treatment for severe childhood obesity. Early referral can significantly improve quality and quantity of life.

Reduction in myocardial strain is evident in adolescents and young adults with obesity and type 2 diabetes

AIMS/HYPOTHESIS

Heart failure is a complication of type 2 diabetes (T2DM). Echocardiography can identify subclinical systolic dysfunction in adults with T2DM. We hypothesized that reduced systolic strain was present in youth with T2DM.

METHODS

Global longitudinal strain (GLS) was measured in 151 subjects with T2DM matched to lean (L = 146), and obese (O = 162) subjects (23.0 ± 4.0 years, 35% male, 63% African American). Anthropometrics, BP, HR, labs, and echocardiograms were obtained. ANOVA was performed to compare differences among groups, and ANCOVA to determine if T2DM remained an independent predictor after corrections.

RESULTS

BP, lipid levels, and metabolic control worsened and GLS was reduced from L to O to T2DM. BMI was lower in L than O or T2DM. Global longitudinal strain rate (GLSR) was lower and LVM/ht^2.7 was higher in O and T2DM as compared to L (all P ≤ .05). Presence of T2DM was an independent determinant of GLS and GLSR adjusted for most CV risk factors, but lost significance when BMI was added to the model. GLS = -21.6-age*0.088 - male*1.8 + 0.12*BMI + 0.045*DBP + 0.058*HR - 0.023*HDL (R² = 0.38, P ≤ .0001); GLSR = -1.20-male*0.093 + WHR*0.48 + DBP*0.0029 (R² = 0.23, P ≤ .0001).

CONCLUSION

Both adiposity and T2DM have a deleterious effect on systolic cardiac function. Treatment of obesity in youth is necessary for prevention of future heart failure.

Left ventricular remodelling and vascular adaptive changes in adolescents with obesity

BACKGROUND

The aim of this study was to determine the effects of obesity on myocardial mechanics and ventriculo-arterial coupling (V-A) in children.

METHODS

Strain parameters, stroke volume, arterial elastance, left ventricular (LV) elastance and V-A were compared after adjusting for age and hypertension and after multivariate sub-group analysis between patients with and without obesity.

RESULTS

Among 123 retrospectively enrolled subjects, 6-21 years age, 79.7% males, 52% were obese. Median (range) Body Mass Index Z score was +2.35 (1.67-4.43) for obese and +0.68 (-2.48-1.63) for non-obese. Subjects with obesity had higher LV mass indexed^2.7 (LVMI^2.7 ) compared with non-obese (P < 0.001). Lower global longitudinal strain (GLS) (P = 0.012), global circumferential strain (GCS) (P = 0.004), average longitudinal strain rate (P = 0.002) and average circumferential strain rate (P < 0.001) were seen in subjects with obesity; no difference was noted in arterial elastance, LV end systolic elastance and V-A. Increased LVMI^2.7 , decreased GLS, GCS, average longitudinal strain rate, average circumferential strain rate and maintained V-A were noted in the multivariate analysis between subgroups.

CONCLUSIONS

Obesity causes alterations in myocardial mechanics with preserved V-A in children. These findings may aid intervention in preventing the long-term cadiovascular effects of obesity.

Diagnostic imaging in the management of patients with metabolic syndrome

Metabolic syndrome (MetS) is the constellation of metabolic risk factors that might foster development of type 2 diabetes and cardiovascular disease. Abdominal obesity and insulin resistance play a prominent role among all metabolic traits of MetS. Because intervention including weight loss can reduce these morbidity and mortality in MetS, early detection of the severity and complications of MetS could be useful. Recent advances in imaging modalities have provided significant insight into the development and progression of abdominal obesity and insulin resistance, as well as target organ injuries. The purpose of this review is to summarize advances in diagnostic imaging modalities in MetS that can be applied for evaluating each components and target organs. This may help in early detection, monitoring target organ injury, and in turn developing novel therapeutic target to alleviate and avert them.

Arterial Thickness and Stiffness Are Independently Associated with Left Ventricular Strain

BACKGROUND

The aim of this study was to examine the association between myocardial strain and arterial thickness and stiffness in young adults. Increased common carotid artery intima media thickness and peripheral arterial stiffness are known to precede coronary artery disease and cardiovascular (CV) events such as myocardial infarction and congestive heart failure. However, subclinical cardiac dysfunction can be detected in high-risk adults by myocardial strain echocardiography. The authors hypothesized that increased carotid artery intima media thickness would be associated with abnormal myocardial strain in young subjects who had obesity and type 2 diabetes mellitus.

METHODS

CV risk factors were collected in 338 young adults participating in a prospective, cross-sectional study. The CV parameters collected included intima-media thickness, peripheral arterial stiffness by brachial distensibility, and myocardial strain and strain rate. General linear models were constructed to determine if vascular structure and function measures were independently associated with myocardial strain and strain rate.

RESULTS

A linear relationship was found between global longitudinal strain obtained from the four-chamber view and global strain rate in systole and carotid intima-media thickness (four-chamber global longitudinal strain: β = 3.0, CV risk factor-adjusted R2 = 0.34; global strain rate in systole: β = 0.0053, R2 = 0.21; P ≤ .0001) and between four-chamber global longitudinal strain and lower brachial distensibility (β = -0.42, R2 = 0.22; P < .001).

CONCLUSIONS

Adverse changes in vascular structure and function are simultaneously present with reduced myocardial systolic function.

Joint statement of the European Association for the Study of Obesity and the European Society of Hypertension: obesity and heart failure

Obese individuals are more likely to develop heart failure. Yet, once heart failure is established, the impact of overweight and obesity on prognosis and survival is unclear. The purpose of this joint scientific statement of the European Association for the Study of Obesity and the European Society of Hypertension is to provide an overview on the current scientific literature on obesity and heart failure in terms of prognosis, mechanisms, and clinical management implications. Moreover, the document identifies open questions that ought to be addressed. The need for more tailored weight management recommendations in heart failure will be emphasized and, in line with the emerging evidence, aims to distinguish between primary disease and secondary outcome prevention. In the primary prevention of heart failure, it appears prudent advising obese individuals to lose or achieve a healthy body weight, especially in those with risk factors such as hypertension or type 2 diabetes. However, there is no evidence from clinical trials to guide weight management in overweight or obese patients with established heart failure. Prospective clinical trials are strongly encouraged.

Left ventricular mechanical dysfunction in diet-induced obese mice is exacerbated during inotropic stress: a cine DENSE cardiovascular magnetic resonance study

BACKGROUND

Obesity is a risk factor for cardiovascular disease. There is evidence of impaired left ventricular (LV) function associated with obesity, which may relate to cardiovascular mortality, but some studies have reported no dysfunction. Ventricular function data are generally acquired under resting conditions, which could mask subtle differences and potentially contribute to these contradictory findings. Furthermore, abnormal ventricular mechanics (strains, strain rates, and torsion) may manifest prior to global changes in cardiac function (i.e., ejection fraction) and may therefore represent more sensitive markers of cardiovascular disease. This study evaluated LV mechanics under both resting and stress conditions with the hypothesis that the LV mechanical dysfunction associated with obesity is exacerbated with stress and manifested at earlier stages of disease compared to baseline.

METHODS

C57BL/6J mice were randomized to a high-fat or control diet (60 %, 10 % kcal from fat, respectively) for varying time intervals (n = 7 - 10 subjects per group per time point, 100 total; 4 - 55 weeks on diet). LV mechanics were quantified under baseline (resting) and/or stress conditions (40 μg/kg/min continuous infusion of dobutamine) using cine displacement encoding with stimulated echoes (DENSE) with 7.4 ms temporal resolution on a 7 T Bruker ClinScan. Peak strain, systolic strain rates, and torsion were quantified. A linear mixed model was used with Benjamini-Hochberg adjustments for multiple comparisons.

RESULTS

Reductions in LV peak longitudinal strain at baseline were first observed in the obese group after 42 weeks, with no differences in systolic strain rates or torsion. Conversely, reductions in longitudinal strain and circumferential and radial strain rates were seen under inotropic stress conditions after only 22 weeks on diet. Furthermore, stress cardiovascular magnetic resonance (CMR) evaluation revealed supranormal values of LV radial strain and torsion in the obese group early on diet, followed by later deficits.

CONCLUSIONS

Differences in left ventricular mechanics in obese mice are exacerbated under stress conditions. Stress CMR demonstrated a broader array of mechanical dysfunction and revealed these differences at earlier time points. Thus, it may be important to evaluate cardiac function in the setting of obesity under stress conditions to fully elucidate the presence of ventricular dysfunction.

Severe Obesity in Adolescents and Young Adults Is Associated With Subclinical Cardiac and Vascular Changes

CONTEXT

Severe obesity is the fastest growing subgroup of obesity in youth.

OBJECTIVE

We sought to explore the association between severe obesity and subclinical measures of cardiac and vascular structure and function in adolescents and young adults.

DESIGN, SETTING, AND PARTICIPANTS

This was a cross-sectional comparison of 265 adolescents and young adults with severe obesity (defined as body mass index [BMI] ≥120% of the 95th percentile) to 182 adolescents and young adults with obesity (defined as BMI ≥100-119th of the 95th percentile) at tertiary medical center.

MAIN OUTCOMES

Noninvasive measures of cardiac and vascular structure and function were assessed.

RESULTS

Participants were a mean age of 17.9 years, 62% were non-Caucasian, and 68% were female. Systolic blood pressure, fasting insulin, C-reactive protein, IL-6, and frequency of type 2 diabetes were higher in participants with severe obesity (all P < .05). Arterial thickness and stiffness, cardiac structure, and diastolic function were also significantly worse in youth with severe obesity as measured by higher left ventricular mass index, worse diastolic function, higher carotid intima media thickness, and pulse wave velocity and lower brachial distensibility (all P < .05). Regression modeling showed that severe obesity (compared with obesity) was independently associated with each of the above outcomes after adjustment for age, race, sex, blood pressure, lipids, and inflammatory markers (P < .05).

CONCLUSIONS

Adolescents and young adults with severe obesity have a more adverse cardiovascular risk profile and worse cardiac and vascular structure and function. More importantly, severe obesity is independently associated with these subclinical cardiac and vascular changes.

Young Women With Abdominal Obesity Have Subclinical Myocardial Dysfunction

BACKGROUND

Abdominal obesity is an independent risk factor for cardiovascular disease. The effect of abdominal obesity on myocardial function in young obese women remains unknown. Therefore, we aimed to investigate cardiac morphology and function, myocardial deformation, and mechanical indices, in young women with and without abdominal obesity.

METHODS

Cross-sectional analyses of 39 women with abdominal obesity (waist circumference ≥ 80 cm) and 33 nonobese control subjects (waist circumference < 80 cm) aged 18-30 years underwent conventional echocardiographic measures of cardiac morphology and function together with tissue Doppler, and 2-dimensional speckle tracking measures of myocardial deformation and mechanics. Cardiometabolic risk factors including anthropometric, hypertension, biochemistry, and fitness were also assessed.

RESULTS

Standard echocardiography results for cardiac morphology and function were similar between groups, with the exception of larger left atrial dimensions in women with abdominal obesity (P ≤ 0.05). Compared with control subjects, women with abdominal obesity also demonstrated reduced systolic and diastolic mitral annular plane velocities, increased left atrial pressure surrogates (E/diastolic mitral annular plane velocity), and prolonged timing measures of diastolic function including isovolumic relaxation time and transmitral deceleration time (P ≤ 0.05). In addition, longitudinal strain and diastolic strain rate were reduced in women with abdominal obesity (P ≤ 0.05) but circumferential deformation and myocardial mechanics (twist indices and rotation) were preserved. Markers of abdominal obesity retained an independent direct correlation with parameters of cardiac dysfunction, explaining 12%-39% of the overall variability.

CONCLUSIONS

A young, otherwise healthy group of women with abdominal obesity displayed subclinical cardiac dysfunction indicated using selected tissue Doppler imaging and speckle tracking echocardiography measures.

Early ventricular remodeling and dysfunction in obese children and adolescents

OPINION STATEMENT

Obesity is an independent predictor of heart failure in adults. Obese individuals have increased hemodynamic load and neuro-hormonal activation that contribute, but cannot entirely explain the reported changes in ventricular structure and function leading to heart failure. There are intrinsic alterations in the myocardium that are independent of load. Insulin resistance promotes alterations in myocardial substrate metabolism that may play a role in the pathogenesis of decreased myocardial efficiency and cardiac dysfunction in obese individuals. The prevalence of obesity in childhood and adolescence has increased significantly over the last decade. Obese children and adolescents have left ventricular remodeling that transpires into adulthood, and subclinical systolic and diastolic dysfunction despite normal conventional parameters of ventricular function. These findings suggest that obesity has an early impact in the cardiovascular health of obese adolescents. Life-style modifications causing weight loss can reverse the ventricular dysfunction observed in this young population and must be strongly encouraged.

Increased myocardial dysfunction, dyssynchrony, and epicardial fat across the lifespan in healthy males

Background

Evaluation of sensitive myocardial mechanics with speckle tracking echocardiography (STE) across the lifespan may reveal early indicators of cardiovascular disease (CVD) risk. Epicardial adipose tissue (EAT) and left ventricular (LV) myocardial dyssynchrony; subclinical risk-factors of CVD, are of particular clinical interest. However, the evolution of EAT and LV-dyssynchrony across the lifespan, and their influence on myocardial dysfunction remains unclear. We aimed to establish a profile of the healthy aging-heart using conventional, tissue-Doppler imaging (TDI) and speckle-tracking echocardiography (STE), while also exploring underlying contributions from EAT and LV-dyssynchrony towards LV myocardial mechanics, independent of blood biology.

Methods

Healthy males aged 19–94 years were recruited through University-wide advertisements in Victoria and New-South Wales, Australia. Following strict exclusion criteria, basic clinical and comprehensive echocardiographic profiles (conventional, TDI and STE) were established. LV-dyssynchrony was calculated from the maximum-delay of time-to-peak velocity/strain in the four LV-annulus sites (TDI), and six LV-segments (STE longitudinal and circumferential axes). Epicardial fat diameter was obtained from two-dimensional grey-scale images in the parasternal long-axis. Blood biological measures included glycemia, hsCRP, triglycerides, total cholesterol, high-density and low-density lipoprotein levels.

Results

Three groups of 15 were assigned to young (<40 years), middle (40–65 years), and older (>65) aged categories. Five participants were excluded from STE analyses due to inadequate image quality. Decreased longitudinal strain, increased circumferential apical strain and LV twist were age-related. Moreover, independent of blood biology, significant increases were observed across age categories for EAT (young: 2.5 ± 0.9 mm, middle: 3.9 ± 1.0 mm, older 5.7 ± 2.4 mm; p < 0.01), longitudinal STE-dyssynchrony (young: 42 ± 7.7 ms, middle: 58.8 ± 18.9 ms, older 88.6 ± 18.2 ms; p < 0.05), and circumferential-basal STE-dyssynchrony (young: 50.2 ± 20.5 ms, middle: 75.9 ± 20.6 ms, older 97.9 ± 20.2 ms; p < 0.05). These variables collectively explained 37% and 31% (p < 0.01) of longitudinal strain and LV twist, respectively.

Conclusions

This study enabled comprehensive profiling of LV mechanics at different stages of aging using sensitive echocardiographic technology. Novel findings included increased epicardial fat, and both longitudinal and circumferential LV-dyssynchrony across the healthy age groups. These factors may be key underlying contributors to myocardial dysfunction during aging, and their recognition may promote an advanced understanding of early signs of cardiovascular disease.

Right ventricle free wall mechanics in metabolic syndrome without type-2 diabetes: effects of a 3-month lifestyle intervention program

Background

Growing evidence demonstrates subtle left ventricular myocardial dysfunction in patients with metabolic syndrome (MetS), with central obesity, glucose intolerance and inflammation emerging as important contributors. Whether these results can be translated to the right ventricle (RV) is not yet fully elucidated. Furthermore, although lifestyle intervention favorably impacts MetS components and inflammatory biomarkers, its effect on RV myocardial function remains unknown today.

Methods

Thirty-nine MetS adults free of diabetes were enrolled in a three month lifestyle intervention program including diet and physical exercise, and compared with forty healthy controls. Blood biochemistry, echocardiography including tissue Doppler imaging (TDI), and vector velocity imaging of the RV free wall to assess global longitudinal strain (GLS) and strain rates (SR) were obtained at baseline and after the intervention.

Results

Compared with controls, MetS patients presented similar right atrial and RV morphology but reduced systolic (P = 0.04) and early diastolic (P = 0.02) velocities of the tricuspid annulus. They showed attenuated RV GLS (−21.4 ± 4.5vs-25.7 ± 4.9%, P < 0.001) as well as early diastolic (P = 0.003) and systolic (P < 0.001) SR. Multiple regression analyses revealed log PAI-1 active, (P < 0.001), log adiponectin, (P = 0.01), LV mass indexed (P = 0.004) and central fat (P = 0.03) as independent predictors of RV GLS (R² = 0.46, P < 0.001). Biological markers of MetS and inflammation as well as RV GLS (−21.8 ± 3.8vs-24.3 ± 3.0%, P = 0.009) and systolic (P = 0.003) and early diastolic (P = 0.01) SR, but not TDI indexes, significantly improved after diet and exercise training, and vector velocity imaging data in MetS following the lifestyle intervention no longer differed from controls.

Conclusions

MetS is associated with subtle impairments in both RV free wall diastolic and systolic myocardial function which could be partly related to central-obesity induced changes in pro- and anti-inflammatory cytokines and left ventricular remodeling. The favorable impact of healthy dieting and physical activity on RV free wall mechanics indicates that cellular and sub-cellular alterations responsible for the RV myocardial abnormalities are probably not permanent and modifiable throughout adequate interventional strategies.

Trial registration

American National Institutes of Health database NCT00917917.

Myocardial deformation and twist mechanics in adults with metabolic syndrome: impact of cumulative metabolic burden

OBJECTIVE

The aim of the study is to characterize left ventricular (LV) myocardial mechanics in adults with metabolic syndrome (MetS), and elucidate the effects of multiple risk-factors on myocardial function using speckle tracking echocardiography (STE); a more sensitive method than conventional echocardiography for detecting subclinical myocardial dysfunction.

DESIGN AND METHODS

Cross-sectional analyses of 92 adults (50-70 years) with MetS, and 50 healthy controls included conventional echocardiography, blood biochemistry, and STE-derived myocardial longitudinal, circumferential, and twist mechanics.

RESULTS

Using conventional measures, MetS participants revealed LV hypertrophy and reduced diastolic function compared with controls, while systolic function was preserved. From STE, MetS participants showed attenuated longitudinal strain (-16.8% ± 2.8% vs. -20.6% ± 2.7%), and both diastolic (1.1 ± 0.2 vs. 1.4 ± 0.3 s s(-1) ) and systolic (-1.0 ± 0.1 vs. -1.2 ± 0.2 s s(-1) ) strain rate (SR). Circumferential strain, SR, and twist mechanics did not differ. Participants with the highest number of MetS factors or diabetes demonstrated the greatest reduction in longitudinal strain and SR. Abdominal obesity, TNF-α, HbA1c , and systolic dyssynchrony explained 48% of impairment in longitudinal strain.

CONCLUSIONS

Impaired longitudinal myocardial diastolic and systolic function, but preserved circumferential function and twist mechanics were found in MetS participants, indicative of altered subendocardial function. This dysfunction was best predicted by abdominal obesity, inflammation, glucose-intolerance, and systolic dyssynchrony.

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.

Severe obesity in children and adolescents: identification, associated health risks, and treatment approaches: a scientific statement from the American Heart Association

Severe obesity afflicts between 4% and 6% of all youth in the United States, and the prevalence is increasing. Despite the serious immediate and long-term cardiovascular, metabolic, and other health consequences of severe pediatric obesity, current treatments are limited in effectiveness and lack widespread availability. Lifestyle modification/behavior-based treatment interventions in youth with severe obesity have demonstrated modest improvement in body mass index status, but participants have generally remained severely obese and often regained weight after the conclusion of the treatment programs. The role of medical management is minimal, because only 1 medication is currently approved for the treatment of obesity in adolescents. Bariatric surgery has generally been effective in reducing body mass index and improving cardiovascular and metabolic risk factors; however, reports of long-term outcomes are few, many youth with severe obesity do not qualify for surgery, and access is limited by lack of insurance coverage. To begin to address these challenges, the purposes of this scientific statement are to (1) provide justification for and recommend a standardized definition of severe obesity in children and adolescents; (2) raise awareness of this serious and growing problem by summarizing the current literature in this area in terms of the epidemiology and trends, associated health risks (immediate and long-term), and challenges and shortcomings of currently available treatment options; and (3) highlight areas in need of future research. Innovative behavior-based treatment, minimally invasive procedures, and medications currently under development all need to be evaluated for their efficacy and safety in this group of patients with high medical and psychosocial risks.