Abnormal systolic and diastolic myocardial function in obese asymptomatic adolescents

Childhood Obesity Is Associated With Subclinical Left Ventricular Dysfunction Detected by Speckle Tracking Echocardiography

Childhood obesity is related to cardiac structural and functional changes, increasing the risk of heart disease. Sixty normotensive children were assigned based on body mass index (BMI) into normal weight, overweight, and obese groups and examined by two-dimensional speckle tracking echocardiography (2D-STE). Weight (P = .001) and BMI (P = .001) differed significantly among the 3 groups. Left ventricular (LV) strain (P = .001) and strain rate (P = .002) in overweight and obese children (P = .001) were significantly lower compared to normal weight group. LV mass in obese children was notably larger compared to overweight children (P = .047). LV strain was associated with age (P = .031), weight (P = .001), and height (P = .022). There was an association between LV strain rate with weight (P = .001) and between left atrial area and height of children (P = .007). Obesity in normotensive obese children is associated with subclinical alteration of LV dimension and myocardial longitudinal strain recognized by 2D-STE.

Chronotropic incompetence is more frequent in obese adolescents and relates to systemic inflammation and exercise intolerance

BACKGROUND

Adults with obesity may display disturbed cardiac chronotropic responses during cardiopulmonary exercise testing, which relates to poor cardiometabolic health and an increased risk for adverse cardiovascular events. It is unknown whether cardiac chronotropic incompetence (CI) during maximal exercise is already present in obese adolescents and, if so, how that relates to cardiometabolic health.

METHODS

Sixty-nine obese adolescents (body mass index standard deviation score = 2.23 ± 0.32, age = 14.1 ± 1.2 years; mean ± SD) and 29 lean adolescents (body mass index standard deviation score = -0.16 ± 0.84, age = 14.0 ± 1.5 years) performed a maximal cardiopulmonary exercise testing from which indicators for peak performance were determined. The resting heart rate and peak heart rate were used to calculate the maximal chronotropic response index. Biochemistry (lipid profile, glycemic control, inflammation, and leptin) was studied in fasted blood samples and during an oral glucose tolerance test within obese adolescents. Regression analyses were applied to examine associations between the presence of CI and blood or exercise capacity parameters, respectively, within obese adolescents.

RESULTS

CI was prevalent in 32 out of 69 obese adolescents (46%) and 3 out of 29 lean adolescents (10%). C-reactive protein was significantly higher in obese adolescents with CI compared to obese adolescents without CI (p = 0.012). Furthermore, peak oxygen uptake and peak cycling power output were significantly reduced (p < 0.05) in obese adolescents with CI vs. obese adolescents without CI. The chronotropic index was independently related to blood total cholesterol (standardized coefficient β = -0.332; p = 0.012) and C-reactive protein concentration (standardized coefficient β = -0.269; p = 0.039).

CONCLUSION

CI is more common in the current cohort of obese adolescents, and is related to systemic inflammation and exercise intolerance.

Left Ventricular Diastolic and Systolic Functions in Patients with Hypothyroidism

Background and objectives: Long standing hypothyroidism may impair myocardial relaxation, but its effect on systolic myocardial function is still controversial. The aim of this study was to investigate left ventricular (LV) systolic and diastolic function in patients with hypothyroidism. Materials and Methods: This study included 81 (age 42 ± 13 years, 92% female) patients with hypothyroidism, and 22 age and gender matched controls. All subjects underwent a detailed clinical examination followed by a complete biochemical blood analysis including thyroid function assessment and anthropometric parameters measurements. LV function was assessed by 2-dimensional, M-mode and Tissue-Doppler Doppler echocardiographic examination performed in the same day. Results: Patients had lower waist/hip ratio (p< 0.001), higher urea level (p = 0.002), and lower white blood cells (p = 0.011), compared with controls. All other clinical, biochemical, and anthropometric data did not differ between the two groups. Patients had impaired LV diastolic function (lower E wave [p< 0.001], higher A wave [p = 0.028], lower E/A ratio [p< 0.001], longer E wave deceleration time [p = 0.01], and higher E/e' ratio [p< 0.001]), compared with controls. Although LV global systolic function did not differ between groups, LV longitudinal systolic function was compromised in patients (lateral mitral annular plane systolic excursion-MAPSE [p = 0.005], as were lateral and septal s' [p< 0.001 for both]). Conclusions: In patients with hypothyroidism, in addition to compromised LV diastolic function, LV longitudinal systolic function is also impaired compared to healthy subjects of the same age and gender. These findings suggest significant subendocardial function impairment, reflecting potentially micro-circulation disease that requires optimum management.

The role of dipeptidylpeptidase-4 inhibitors in management of cardiovascular disease in diabetes; focus on linagliptin

Multiple population based analyses have demonstrated a high incidence of cardiovascular disease (CVD) and cardiovascular (CV) mortality in subjects with T2DM that reduces life expectancy by as much as 15 years. Importantly, the CV system is particularly sensitive to the metabolic and immune derangements present in obese pre-diabetic and diabetic individuals; consequently, CV dysfunction is often the initial CV derangement to occur and promotes the progression to end organ/tissue damage in T2DM. Specifically, diabetic CVD can manifest as microvascular complications, such as nephropathy, retinopathy, and neuropathy, as well as, macrovascular impairments, including ischemic heart disease, peripheral vascular disease, and cerebrovascular disease. Despite some progress in prevention and treatment of CVD, mainly via blood pressure and dyslipidemia control strategies, the impact of metabolic disease on CV outcomes is still a major challenge and persists in proportion to the epidemics of obesity and diabetes. There is abundant pre-clinical and clinical evidence implicating the DPP-4-incretin axis in CVD. In this regard, linagliptin is a unique DPP-4 inhibitor with both CV and renal safety profiles. Moreover, it exerts beneficial CV effects beyond glycemic control and beyond class effects. Linagliptin is protective for both macrovascular and microvascular complications of diabetes in preclinical models, as well as clinical models. Given the role of endothelial-immune cell interactions as one of the key events in the initiation and progression of CVD, linagliptin modulates these cell–cell interactions by affecting two important pathways involving stimulation of NO signaling and potent inhibition of a key immunoregulatory molecule.

No Obesity Paradox in Pediatric Patients With Dilated Cardiomyopathy

OBJECTIVES

This study aimed to examine the role of nutrition in pediatric dilated cardiomyopathy (DCM).

BACKGROUND

In adults with DCM, malnutrition is associated with mortality, whereas obesity is associated with survival.

METHODS

The National Heart, Lung, and Blood Institute-funded Pediatric Cardiomyopathy Registry was used to identify patients with DCM and categorized by anthropometric measurements: malnourished (MN) (body mass index [BMI] <5% for age ≥2 years or weight-for-length <5% for <2 years), obesity (BMI >95% for age ≥2 years or weight-for-length >95% for <2 years), or normal bodyweight (NB). Of 904 patients with DCM, 23.7% (n = 214) were MN, 13.3% (n=120) were obese, and 63.1% (n=570) were NB.

RESULTS

Obese patients were older (9.0 vs. 5.7 years for NB; p < 0.001) and more likely to have a family history of DCM (36.1% vs. 23.5% for NB; p = 0.023). MN patients were younger (2.7 years vs. 5.7 years for NB; p < 0.001) and more likely to have heart failure (79.9% vs. 69.7% for NB; p = 0.012), cardiac dimension z-scores >2, and higher ventricular mass compared with NB. In multivariable analysis, MN was associated with increased risk of death (hazard ratio [HR]: 2.06; 95% confidence interval [CI]: 1.66 to 3.65; p < 0.001); whereas obesity was not (HR: 1.49; 95% CI: 0.72 to 3.08). Competing outcomes analysis demonstrated increased risk of mortality for MN compared with NB (p = 0.03), but no difference in transplant rate (p = 0.159).

CONCLUSIONS

Malnutrition is associated with increased mortality and other unfavorable echocardiographic and clinical outcomes compared with those of NB. The same effect of obesity on survival was not observed. Further studies are needed investigating the long-term impact of abnormal anthropometric measurements on outcomes in pediatric DCM. (Pediatric Cardiomyopathy Registry; NCT00005391).

Early cardiac abnormalities in obese children and their relationship with adiposity

OBJECTIVES

Childhood obesity rates are increasing as well as chronic disease and cardiovascular risk factors for patients at young ages. In this study, we evaluate the correlation between cardiac parameters, body mass index (BMI), and other body composition indicators in children and adolescents.

METHODS

In this cross-sectional study, we evaluated anthropometric measurements, bioelectrical impedance parameters, and echocardiographic measurements including the left ventricular mass (LVM), LVM index (LVMI), and left atrial diameter (LAD) in children and adolescents ages 7 to 15 y. We performed linear and multivariate regression analyses and analyzed the correlations between cardiac parameters, BMI, and other body composition parameters.

RESULTS

We analyzed 96 children and adolescents and found 40.6% to be obese and 29.2% overweight. LVMI and LAD indexed to height were significantly higher in individuals who were obese. LVMI increased significantly with increasing BMI (r = 0.717; P < 0.001), waist circumference (r = 0.670; P < 0.001), waist-to-height ratio (r = 0.650; P < 0.001), and body surface (r = 0.570; P < 0.001). Only BMI was significant in the multivariate analysis. LVMI was directly and positively correlated with fat mass (FM) and percentage of visceral and abdominal FM and negatively correlated with percentage of lean body mass. LAD was significantly correlated with body surface (r = 0.728; P < 0.001), BMI (r = 0.611; P < 0.001), waist circumference (r = 0.614; P < 0.001), and waist-to-height ratio (r = 0.341; P < 0.01). When indexed to height, LAD was only correlated with BMI and waist-to-height ratio.

CONCLUSIONS

Obesity is associated with cardiac disturbances at a very early age and these changes are closely related to the degree of adiposity. Cardiac structural parameters are significantly correlated with BMI and waist circumference in pediatric patients ages 7 to 15 y.

Obesity and type 2 diabetes have additive effects on left ventricular remodelling in normotensive patients-a cross sectional study

Background

It is unclear whether obesity and type 2 diabetes (T2D), either alone or in combination, induce left ventricular hypertrophy (LVH) independent of hypertension. In the current study, we provide clarity on this issue by rigorously analysing patient left ventricular (LV) structure via clinical indices and via LV geometric patterns (more commonly used in research settings). Importantly, our sample consisted of hypertensive patients that are routinely screened for LVH via echocardiography and normotensive patients that would normally be deemed low risk with no further action required.

Methods

This cross sectional study comprised a total of 353 Caucasian patients, grouped based on diagnosis of obesity, T2D and hypertension, with normotensive obese patients further separated based on metabolic health. Basic metabolic parameters were collected and LV structure and function were assessed via transthoracic echocardiography. Multivariable logistic and linear regression analyses were used to identify predictors of LVH and diastolic dysfunction.

Results

Metabolically healthy normotensive obese patients exhibited relatively low risk of LVH. However, normotensive metabolically non-healthy obese, T2D and obese/T2D patients all presented with reduced normal LV geometry that coincided with increased LV concentric remodelling. Furthermore, normotensive patients presenting with both obesity and T2D had a higher incidence of concentric hypertrophy and grade 3 diastolic dysfunction than normotensive patients with either condition alone, indicating an additive effect of obesity and T2D. Alarmingly these alterations were at a comparable prevalence to that observed in hypertensive patients. Interestingly, assessment of LVPWd, a traditional index of LVH, underestimated the presence of LV concentric remodelling. The implications for which were demonstrated by concentric remodelling and concentric hypertrophy strongly associating with grade 1 and 3 diastolic dysfunction respectively, independent of sex, age and BMI. Finally, pulse pressure was identified as a strong predictor of LV remodelling within normotensive patients.

Conclusions

These findings show that metabolically non-healthy obese, T2D and obese/T2D patients can develop LVH independent of hypertension. Furthermore, that LVPWd may underestimate LV remodelling in these patient groups and that pulse pressure can be used as convenient predictor of hypertrophy status.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0504-z) contains supplementary material, which is available to authorized users.

Effect of obesity on left ventricular longitudinal myocardial strain by speckle tracking echocardiography in children and adolescents

BACKGROUND

Impaired subclinical ventricular function may contribute to the risk of cardiovascular disease in obesity.

AIMS

The aim of this study was to determine the influence of obesity on left ventricular (LV) longitudinal myocardial function in normotensive obese children using two-dimensional (2D) speckle tracking echocardiography (STE).

STUDY DESIGN

Case-control study.

METHODS

Sixty normotensive obese children aged 10-16 years (mean age, 13.9±2.3 years) were compared with 50 normal-weight controls. Obese participants had a body mass index (BMI)≥95(th) percentile. Regional strain/strain rate (SR) values were compared with left ventricular (LV) parameters. The correlation was studied by linear regression analysis.

RESULTS

Obese subjects exhibited a significantly higher LV end-diastolic diameter, left atrium/aortic diameter ratio, and LV mass/index when compared to controls (p<0.001). Left ventricular ejection fraction and regional systolic myocardial velocities were similar in the obese and control groups. By 2D STE, regional strain of both the septal wall (average strain: -16.0±3.9% vs -21.9±2.4%, p<0.001) and lateral wall (average strain: -15.6±2.3% vs -22.9±3.5%, p<0.001); regional SR of both the septal wall (average SRsys: -0.7±0.22 s(-1) vs -1.3±0.32 s(-1), p<0.001) and lateral wall (average SRsys: -0.67±0.19 s(-1) vs -1.33±0.31 s(-1), p<0.001); regional SRE/A of both the septal wall (average SRE/A: 1.8±0.83 vs. 2.2±0.91, p: 0.004) and lateral wall (average SRE/A: 1.4±0.43 vs. 2.4±1.21, p<0.001); and global strain (-14.6±7.34% vs -20.9±3.24%, p<0.001) were lower in the obese group compared with the controls. These strain imaging parameters appear to be related to the severity of obesity and can contribute to increased BMI. Left ventricular mass was found to be correlated with a decrease in global LV strain.

CONCLUSION

Our study showed that childhood obesity is associated with an alteration in the longitudinal LV function. Segmental analysis of the LV can provide subtle markers for the emergence of future obesity-related cardiac disease.

Left ventricular diastolic function and cardiometabolic factors in obese normotensive children

BACKGROUND AND AIM

Left ventricular (LV) hypertrophy and diastolic function have been found to be associated with obesity and hypertension in adults. However, there are scarce data about the association of obesity itself to cardiac alteration in children. The aim of this study was to detect early changes in LV structure and function in obese children and whether they are associated with the biomarkers of metabolic risk and endothelial activation.

METHODS AND RESULTS

A total of 130 children aged 7-16 years (88 obese and 42 normal-weight children) were studied. All children had normal resting blood pressure. Two-dimensional ultrasound with M-mode imaging was performed to assess the LV mass index (LVMi), calculated as LV mass/height(2.7), and the peak diastolic of pulmonary venous flow velocity (PVFD). Tissue Doppler imaging was used to analyze ventricular performance through the ratio of the transmitral peak early filling velocity to the early average diastolic peak myocardial velocity (E/E'). The indicators of metabolic control, inflammation, and endothelial cell activation were evaluated. Compared to the controls, the obese subjects had significantly higher LVMi and E/E' and lower PVFD values, the two latest being found especially in severely obese subjects. In the multivariate analysis, the parameters of diastolic function (E/E' and PVFD) were independently associated with obesity, apolipoprotein A1, soluble vascular cell endothelial molecule-1 (sVCAM-1), and retinol-binding protein 4 (RBP4).

CONCLUSION

An echocardiographic evaluation of diastolic function is a useful tool to detect early cardiac changes in obese children. Emergent cardiovascular risk markers such as apolipoprotein A1, RBP4, and sVCAM-1 are associated with the parameters of diastolic function.

Fibroblast growth factor-23 in obese, normotensive adolescents is associated with adverse cardiac structure

OBJECTIVES

Fibroblast growth factor-23 (FGF23) is a biomarker for cardiovascular disease. Obesity may promote FGF23 production in the absence of chronic kidney disease. We sought to determine among normotensive African American adolescents whether FGF23 levels are greater in obese compared with normal-weight adolescents and to determine the relationship of FGF23 with markers of cardiac structure and insulin resistance.

STUDY DESIGN

Cross-sectional data were obtained from a cohort of 130 normotensive, African American adolescents ages 13-18 years without chronic kidney disease; 74 were obese; 56 were normal weight. Plasma C-terminal FGF23, fasting glucose and insulin, and high-sensitivity C-reactive protein were measured; participants underwent M-mode echocardiography.

RESULTS

FGF23 was skewed and approximately normally distributed after natural log transformation (logFGF23). FGF23 levels were greater in obese vs normal-weight participants (geometric mean 43 vs 23 RU/mL, P < .01). FGF23 values were significantly greater in participants with eccentric or concentric cardiac hypertrophy compared with those without hypertrophy P < .01). LogFGF23 directly correlated with body mass index, body mass index z-score, waist circumference, fasting insulin levels, and homeostasis model assessment scores. Regression models adjusted for age, sex, and high-sensitivity C-reactive protein suggest that each 10% increase in FGF23 is associated with a 1.31 unit increase in left ventricular mass (P < .01), a 0.29-unit increase in left ventricular mass index (P < .01), and a 0.01-unit increase in left atrial dimension indexed to height (P = .02).

CONCLUSIONS

In this sample of obese African American adolescents, FGF23 blood levels were associated with abnormal cardiac structure. We postulate that FGF23 may be an early marker of cardiac injury in obese but otherwise-healthy African American adolescents.

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.