Predictors Of Left Ventricular Mass Research Articles

Predictors of left ventricular mass and coronary artery calcium phenotypes

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): National Medical Research Council, Ministry of Health, Singapore and the Lee Foundation Background Left ventricular (LV) mass and coronary artery calcium score (CACS) are both independent predictors of cardiovascular risk. There is paucity of data on the interplay of risk factors on LV mass in the presence or absence of subclinical coronary atherosclerosis. Purpose The objective of this present study was to explore the relationship of risk factors to indexed LV mass and CACS in a healthy Southeast-Asian population. Methods This study recruited volunteers with no known cardiovascular disease. LV mass, measured by cardiovascular magnetic resonance, was indexed to body surface area (LVMI), and CACS determined by non-contrast CT scanning. Blood pressure (BP) was measured via both office and ambulatory monitoring, and physical activity assessed through wearable devices. Analysis of LVMI was stratified into high, normal and low defined as more than one standard deviation away from the mean for each sex, with inter-group differences evaluated using chi-squared or ANOVA statistical tests. Subjects in each LVMI group were further subdivided by the presence and absence of coronary calcification (total 6 subgroups; LVMI/CACS phenotypes). Results A total of 880 subjects were included, including 428 males and 452 females. There was no significant difference in prevalence of coronary calcification across the LVMI groups for males, while females with high LVMI had significantly greater proportion of positive CACS (p = 0.036). Higher LVMI was observed in younger male subjects, but not in females. In both sexes, body mass index was positively associated with LVMI (p = 0.004 for males, p = 0.037 for females), but not CACS. Waist circumference was associated with higher LVMI in males only. Greater amounts of weekly self-reported exercise (p = 0.006) and daily calories burned (p = 0.022) were associated with increased LVMI for males only. However, wearable-derived measures of daily physical activity and step counts did not significantly affect LVMI or LVMI/CACS phenotypes in both sexes. BP was a strong predictor of LVMI in both sexes regardless of office or ambulatory readings, in both day and night-time. The association was also observed with LVMI/CACS phenotypes: higher systolic or diastolic BP was significantly associated with positive CACS across all risk groups. Notably, subjects with low LVMI and positive CACS were normotensive (office BP 129/82 for males, 123/77 for females). Higher HDL cholesterol levels correlated to absence of coronary calcification in males only (p = 0.010). In females, lower levels of total (p = 0.001) and LDL (p = 0.005) cholesterol were associated with absence of coronary calcification across all LVMI categories. Conclusion Only BP was strongly associated with LVMI and LVMI/CACS phenotypes in both sexes. There appears to be no correlation between physical activity and LVMI/CACS phenotypes. There is a need for causative studies to better evaluate the varying influence of risk factors on LVMI and CACS.

Relating QRS voltages to left ventricular mass and body composition in elite endurance athletes.

Electrocardiogram (ECG) QRS voltages correlate poorly with left ventricular mass (LVM). Body composition explains some of the QRS voltage variability. The relation between QRS voltages, LVM and body composition in endurance athletes is unknown. Elite endurance athletes from the Pro@Heart trial were evaluated with 12-lead ECG for Cornell and Sokolow-Lyon voltage and product. Cardiac magnetic resonance imaging assessed LVM. Dual energy x-ray absorptiometry assessed fat mass (FM) and lean mass of the trunk and whole body (LBM). The determinants of QRS voltages and LVM were identified by multivariable linear regression. Models combining ECG, demographics, DEXA and exercise capacity to predict LVM were developed. In 122 athletes (19years, 71.3% male) LVM was a determinant of the Sokolow-Lyon voltage and product (β = 0.334 and 0.477, p < 0.001) but not of the Cornell criteria. FM of the trunk (β = -0.186 and -0.180, p < 0.05) negatively influenced the Cornell voltage and product but not the Sokolow-Lyon criteria. DEXA marginally improved the prediction of LVM by ECG (r = 0.773 vs 0.510, p < 0.001; RMSE = 18.9 ± 13.8 vs 25.5 ± 18.7g, p > 0.05) with LBM as the strongest predictor (β = 0.664, p < 0.001). DEXA did not improve the prediction of LVM by ECG and demographics combined and LVM was best predicted by including VO2max (r = 0.845, RMSE = 15.9 ± 11.6g). LVM correlates poorly with QRS voltages with adipose tissue as a minor determinant in elite endurance athletes. LBM is the strongest single predictor of LVM but only marginally improves LVM prediction beyond ECG variables. In endurance athletes, LVM is best predicted by combining ECG, demographics and VO2max.

Abstract 51: Ambulatory Blood Pressure Phenotype And Cardiovascular Risk In Youth: The Ship-ahoy Study

We investigated whether blood pressure (BP) phenotype based on clinic &amp; 24-hour ambulatory BP (ABP) was associated with intermediate markers of cardiovascular disease (CVD) in 374 adolescents enrolled in a study of the relationship of BP to CV risk. Clinic BP was measured by auscultation and categorized using the 2017 AAP guideline. ABP was measured for 24 hours by an oscillometric device and analyzed using the adult ABP wake SBP cut-point (130 mmHg). This created 4 BP phenotype groups: normal BP (n=224), white coat hypertensive (n=48), ambulatory hypertensive (n=57) &amp; masked hypertensive (n=45). Echocardiographic parameters &amp; carotid-femoral pulse wave velocity (PWVcf) were measured to assess CVD risk. Left ventricular mass (LVM) was lowest in the normal BP group, whereas multiple measures of cardiac function and PWVcf were worse in the masked and ambulatory hypertensive groups: Generalized linear models adjusted for body mass index (BMI) were constructed to examine the associations between BP phenotype and the measured CVD variables. ABP phenotype was an independent predictor of LVM, diastolic and systolic function and PWVcf in the unadjusted model. ABP phenotype remained significantly associated with diastolic function (E/e’, e’/a’), systolic function (ejection fraction) and increased arterial stiffness (PWVcf) after adjustment for BMI percentile (all p&lt;=0.05). We conclude that BP phenotype is an independent predictor of markers of increased CVD risk in adolescents, including impaired cardiac function and increased vascular stiffness. ABP monitoring has an important role in CVD risk assessment in youth.

Is the burden of late hypertension and cardiovascular target organ damage in children and adolescents with coarctation of the aorta after early successful repair different to healthy controls?

Cardiovascular morbidity is high in patients with coarctation of aorta even after successful repair. This study aimed to assess the frequency of late hypertension and the relationship between ambulatory hypertension and cardiovascular target organ damage in children and adolescents after early and successful repair of coarctation of the aorta. Twenty-five children and adolescents (mean age 13.5 ± 3.43 years) with repaired coarctation of the aorta (median age at repair 4 months, arm-leg gradient <20 mmHg) and 16 healthy controls were included. Office and ambulatory blood pressure, pulse wave velocity, and left ventricular mass index were assessed. Both day- and night-time systolic blood pressure standard deviation score and left ventricular mass index were significantly higher in patients compared to controls (p ≤ 0.001 for all), whereas pulse wave velocity did not differ. The prevalence of masked hypertension, isolated nocturnal hypertension, and left ventricular hypertrophy were 40, 28, and 24%, respectively. Left ventricular mass index was higher in patients with sustained hypertension, masked hypertension, and normotension compared to controls (p < 0.05). In multivariate analysis, higher night-time systolic blood pressure standard deviation score was the only independent predictor of left ventricular mass index. The present study reveals a high prevalence of masked hypertension, isolated nocturnal hypertension, and left ventricular hypertrophy in children and adolescents with coarctation of the aorta even after early and successful repair. Ambulatory blood pressure monitoring should be considered to diagnose hypertension. All coarctation of aorta patients should be followed up lifelong and encouraged to establish a healthy lifestyle starting from childhood.

Scaling left ventricular mass in adolescent female soccer players

BackgroundThe aim of the study was to examine the contribution of chronological age (CA), skeletal maturation, training experience and concurrent body size descriptors, to inter-individual variance in left ventricular mass (LVM) among female adolescent soccer players.MethodsThe sample included 228 female soccer players 11.8–17.1 years. Training experience defined as years of participation in competitive soccer (range 2–9 years), was obtained by interview. Stature, body mass and skinfolds (triceps, medial calf) were measured. Fat mass was estimated; Fat-free mass was derived. LVM was assessed by echocardiography. Skeletal maturity status was as the difference of skeletal age (SA, Fels method) minus CA.ResultsFat-free mass was the most prominent single predictor of LVM (R2 = 36.6%). It was associated with an allometric coefficient close to linearity (k = 0.924, 95%CI: 0.737 to 1.112). A significant multiplicative allometric model including body mass, fat-free mass, CA, training experience and skeletal maturity status was also obtained (R = 0.684; R2 = 46.2%).ConclusionStature has limitations as a valid size descriptor of LVM. Body mass, fat-free mass, training experience, CA, body mass and skeletal maturity status were relevant factors contributing to inter-individual variability in LVM.

Lean body mass is the strongest anthropometric predictor of left ventricular mass in the obese paediatric population.

Indexing left ventricular mass to body surface area or height2.7 leads to inaccuracies in diagnosing left ventricular hypertrophy in obese children. Lean body mass predictive equations provide the opportunity to determine the utility of lean body mass in indexing left ventricular mass. Our objectives were to compare the diagnostic accuracy of predicted lean body mass, body surface area, and height in detecting abnormal left ventricle mass in obese children. Obese non-hypertensive patients aged 4-21 years were recruited prospectively. Dual-energy X-ray absorptiometry was used to measure lean body mass. Height, weight, sex, race, and body mass index z-score were used to calculate predicted lean body mass. We enrolled 328 patients. Average age was 12.6 ± 3.8 years. Measured lean body mass had the strongest relationship with left ventricular mass (R2 = 0.84, p < 0.01) compared to predicted lean body mass (R2 = 0.82, p < 0.01), body surface area (R2 = 0.80, p < 0.01), and height2.7 (R2 = 0.65, p < 0.01). Of the clinically derived variables, predicted lean body mass was the only measure to have an independent association with left ventricular mass (β = 0.90, p < 0.01). Predicted lean body mass was the most accurate scaling variable in detecting left ventricular hypertrophy (positive predictive value = 88%, negative predictive value = 99%). Lean body mass is the strongest predictor of left ventricular mass in obese children. Predicted lean body mass is the most accurate anthropometric scaling variable for left ventricular mass in left ventricular hypertrophy detection. Predicted lean body mass should be considered for clinical use as the body size correcting variable for left ventricular mass in obese children.

VALIDATION OF INAPPROPRIATE LEFT VENTRICULAR MASS DEFINED BY AMBULATORY SYSTOLIC BLOOD PRESSURE IN MULTICENTER REGISTRY STUDY DATABASE

Objective:Inappropriately high left ventricular mass (LVM) (ihLVM) was reported to be risk marker for cardiovascular event regardless of the presence of left ventricular hypertrophy (LVH). But the prediction of LVM is limited by inaccurate calculation of stroke work (SW) using casual systolic blood

Biomarkers of Myocardial Fibrosis: Revealing the Natural History of Fibrogenesis in Fabry Disease Cardiomyopathy.

BackgroundCardiomyopathy is a major determinant of overall Fabry disease (FD) prognosis, with the worst outcomes in patients with myocardial fibrosis. Late gadolinium enhancement is currently the gold standard for evaluation of replacement myocardial fibrosis; however, this event is irreversible, thus identification of biomarkers of earlier diffuse fibrosis is paramount.Methods and ResultsType I collagen synthesis and degradation biomarkers (PICP [carboxyterminal propeptide of procollagen type I], ICTP [carboxyterminal telopeptide of type I collagen], and MMP1 [matrix metalloproteinase 1] and MMP2) and markers of bone synthesis and degradation were evaluated (to adjust type I collagen metabolism to bone turnover) in FD patients and controls. FD patients were grouped by cardiomyopathy severity, according to echocardiogram: (1) normal, (2) tissue Doppler abnormalities, (3) left ventricular hypertrophy. A significant increase in PICP and a significant decrease in matrix metalloproteinases were observed in FD patients; even the group with normal echocardiogram had a significant increase in PICP. We also found a significant correlation between left ventricular mass and PICP (ρ=0.378, P=0.003) and MMP1 (ρ=−0.484, P<0.001). PICP (adjusted for bone turnover) was the better predictor of left ventricular mass in multivariable regression, and its diagnostic accuracy to predict late gadolinium enhancement was also significant.ConclusionsCollagen type I synthesis is increased in FD cardiomyopathy, even in the earlier stages of the disease, and this profibrotic state has good predictive value for and is likely to be critical to the development of overt left ventricular hypertrophy. Moreover, inhibition of enzymes involved in collagen type I cleavage also seems crucial to myocardial collagen deposition.

Lung function and left ventricular hypertrophy in morbidly obese candidates for bariatric surgery.

Objective: To look for correlations between lung function and cardiac dimension variables in morbidly obese patients, in order to test the hypothesis that the relative size of the small airways is independently correlated with left ventricular hypertrophy. Methods: This was a retrospective study involving 192 medical records containing a clinical protocol employed in candidates for bariatric surgery between January of 2006 and December of 2010. Results: Of the 192 patients evaluated, 39 (10 males and 29 females) met the inclusion criteria. The mean BMI of the patients was 49.2 ± 7.6 kg/m2, and the mean age was 35.5 ± 7.7 years. The FEF25-75/FVC, % correlated significantly with left ventricular posterior wall thickness and relative left ventricular posterior wall thickness, those correlations remaining statistically significant (r = −0.355 and r = −0.349, respectively) after adjustment for weight, gender, and history of systemic arterial hypertension. Stepwise multivariate linear regression analysis showed that FVC and FEV1 were the major determinants of left ventricular mass (in grams or indexed to body surface area). Conclusions: A reduction in the relative size of the small airways appears to be independently correlated with obesity-related cardiac hypertrophy, regardless of factors affecting respiratory mechanics (BMI and weight), gender, or history of systemic arterial hypertension. However, FEV1 and FVC might be important predictors of left ventricular mass in morbidly obese individuals.

Sex-related differences in left ventricular structure in early adolescent non-professional athletes.

Professional athletes exhibit lower left ventricular wall thicknesses, diameters and mass (in females), with less frequent training-related electrocardiogram (ECG) changes, as compared with controls. We studied the association of sex with left ventricular structure in trained early adolescents. Two hundred and six adolescent Caucasian athletes (mean age 13.8 ± 1.6, range 11.8-16.9 years, 158 males and 48 females), with similar degree of training underwent ECG and echocardiographic measurements of left ventricular diameters, thicknesses and mass, with relative wall thickness as the remodelling index. As compared with females, males exhibited greater maximal wall thickness (males = 8.7 ± 1.2 vs. females = 7.9 ± 0.8) and indexed left ventricular mass (100 ± 18 g/m(2) vs. 79 ± 12, p < 0.001), without differences in relative wall thickness (males = 0.35 ± 0.04 vs. females = 0.34 ± 0.04) and with higher prevalence of ECG-based left ventricular hypertrophy, sinus bradycardia and ST-elevation. An analysis of covariance, using age, body surface area, systolic blood pressure, heart rate and sex as the covariates, reported that sex is a strong predictor of left ventricular mass, maximal wall thickness, left ventricular diastolic diameter and ECG-based left ventricular hypertrophy. In a binary logistic regression model analysis sex, like left ventricular mass, predicted ST-trait elevation. Our results suggest that, in early adolescence, female athletes have lower left ventricular mass and thicknesses compared with males, without geometrical differences. Therefore, sex, independent of age, is a strong determinant of structural parameters also in early adolescent athletes. These data indicate that sex-specific parameters are needed in the pre-participation cardiovascular screening of adolescent athletes.

Resistive and pulsatile arterial load as predictors of left ventricular mass and geometry: the multi-ethnic study of atherosclerosis.

Arterial load is composed of resistive and various pulsatile components, but their relative contributions to left ventricular (LV) remodeling in the general population are unknown. We studied 4145 participants enrolled in the Multi-Ethnic Study of Atherosclerosis, who underwent cardiac MRI and radial arterial tonometry. We computed systemic vascular resistance (SVR=mean arterial pressure/cardiac output) and indices of pulsatile load including total arterial compliance (TAC, approximated as stroke volume/central pulse pressure), forward wave amplitude (Pf), and reflected wave amplitude (Pb). TAC and SVR were adjusted for body surface area to allow for appropriate sex comparisons. We performed allometric adjustment of LV mass for body size and sex and computed standardized regression coefficients (β) for each measure of arterial load. In multivariable regression models that adjusted for multiple confounders, SVR (β=0.08; P<0.001), TAC (β=0.44; P<0.001), Pb (β=0.73; P<0.001), and Pf (β=-0.23; P=0.001) were significant independent predictors of LV mass. Conversely, TAC (β=-0.43; P<0.001), SVR (β=0.22; P<0.001), and Pf (β=-0.18; P=0.004) were independently associated with the LV wall/LV cavity volume ratio. Women demonstrated greater pulsatile load than men, as evidenced by a lower indexed TAC (0.89 versus 1.04 mL/mm Hg per square meter; P<0.0001), whereas men demonstrated a higher indexed SVR (34.0 versus 32.8 Wood Units×m2; P<0.0001). In conclusion, various components of arterial load differentially associate with LV hypertrophy and concentric remodeling. Women demonstrated greater pulsatile load than men. For both LV mass and the LV wall/LV cavity volume ratio, the loading sequence (ie, early load versus late load) is an important determinant of LV response to arterial load.

How does stress possibly affect cardiac remodeling?

The aim of this study was to evaluate the predictive value of adrenocorticotropic hormone (ACTH), cortisol and ACTH receptor polymorphism (ACTHRP) for left ventricular (LV) remodeling. Thirty-six elite male athletes, as chronic stress adaptation models, and twenty sedentary age and sex-mached subjects emabarked on standard and tissue Doppler echocardiography to assess cardiac parameters at rest. They performed maximal cardiopulmonary test, which was used as an acute stress model. ACTH and cortisol were measured at rest (10min before test), at beginning, at maximal effort, at 3rd min of recovery, using radioimmunometric and radioimmunoassey techniques, respectively. Promoter region of ACTHR gene (18p11.2) was analysed from blood samples using reverse polymerization reaction with the analysis of restriction fragment length polimorphisam by SacI restriction enzyme. Normal genotype was CTC/CTC, heterozygot for ACTHRP CTC/CCC and homozygot CCC/CCC. In all participants, ACTH and cortisol increased during acute stress, whereas in recovery ACTH increased and cortisol remained unchanged. 49/56 examiners manifested CTC/CTC, 7/56 CTC/CCC and 0/56 CCC/CCC. There was no difference in ACTHRP frequency between groups (χ(1)2=0.178, p=0.67). LV mass (LVM) and LV end-diastolic volume (LVVd) were higher in athletes than in controls (p<0.01) and lower in CTC/CTC than in CTC/CCC genotype (219.43±46.59(SD)g vs. 276.34±48.86(SD)g, p=0.004; 141.24±24.46(SD)ml vs. 175.29±37.07(SD)ml, p=0.002; respectively). In all participants, predictors of LVM and LVVd were ACTH at rest (B=−1.00,−0.44; β=−0.30,−0.31; p=0.026,0.012, respectively) and ACTHRP (B=56.63,34; β=0.37,0.40; p=0.003,0.001, respectively). These results demonstrate that ACTH and ACTHRP strongly predict cardiac morphology suggesting possible regulatory role of stress system activity and sensitivity in cardiac remodeling.

Relationship between serum fibroblast growth factor 23 levels and left ventricular mass measured by three-dimensional echocardiography in patients with end-stage renal disease

Purpose: In patients with chronic renal insufficiency traditional risk factors of left ventricular (LV) hypertrophy include hypertension, overhydration, anemia and impaired calcium-phosphate homeostasis. Fibroblast growth factor 23 (FGF-23) is a phosphaturic hormone secreted by osteoblasts and a rising biomarker associated with LV hypertrophy and mortality in patients with end-stage renal disease (ESRD). We sought to determine the relationship between serum FGF-23 levels and left venticular mass measured by three-dimensional (3D) echocardiography in ESRD patients. Methods: This retrospective cohort study included 44 patients (mean age 48±13 years, 54% men) with ESRD on three times per week maintenance hemodialysis. Exclusion criteria were previous history of diabetes and any significant cardiac disease. Beyond conventional transthoracic echocardiographic examination, 3D recordings were obtained using multi-beat reconstruction from 6 consecutive cardiac cycles (GE Vivid E9). After semi-automated tracing of LV endo- and epicardial surface at end-diastolic frame, LV mass was calculated using dedicated software (GE 4D Auto LVQ). Serum FGF-23 levels were measured by enzyme-linked immunosorbent assay (Merck Millipore). Overhydration evaluated by bioimpedance (Fresenius Body Composition Monitor), laboratory test results (including serum calcium, phosphate, parathormone, total iron binding capacity levels) and blood pressure were recorded and averaged in the three previous months. Relationships were calculated by Spearman correlation test and multivariate linear regression. Results: The median value of LV mass measured in ESRD patients was 244 grams (interquartile range 97.5). Serum FGF-23 levels ranged between 34 and 6848 with a median of 687 pg/ml. Serum levels of FGF-23 (ρ=0.52), phosphate (ρ=0.55), parathormone (ρ=0.38), total iron binding capacity (ρ=0.61), systolic blood pressure (ρ=0.38) and pulse pressure (ρ=0.47, all p<0.05) correlated significantly with LV mass. FGF-23 correlated with serum phosphate (ρ=0.83) and parathormone (ρ=0.53, both p<0.001) levels. In a multivariate linear regression model, FGF-23 (β=0.42, p<0.001), total iron binding capacity (β=0.49, p<0.001) and systolic blood pressure (β=0.37, p<0.01) were found to be independent predictors of LV mass. Conclusions: To the best of our knowledge, this is the first study which demonstrates the strong correlation between serum FGF-23 levels and LV mass measured by 3D echocardiography. Beside the chronic volume- and pressure overload, LV hypertrophy is strongly determined by the endocrine effects of FGF-23 in patients with ESRD.

Sex differences in the relationship between adiposity and left ventricular morphology

Background: Studies examining sex differences in the association between adiposity and left ventricular (LV) structure have been inconsistent. Many studies have used body-mass index (BMI), which combines influences from both lean mass and fat mass, potentially limiting its use for studying the relationship between adiposity and LV structure. Therefore, we aimed to delineate the relationship between lean mass and fat mass with LV mass and volume in both men and women using cardiovascular magnetic resonance (CMR). Methods: 221 adult volunteers (127 female, age range 18-72 years, mean 40.3 years) were recruited via advertisement. In order to study the effects of uncomplicated adiposity, volunteers were excluded if they gave a history of cardiovascular-related disease, including hypertension, hypercholesterolemia and diabetes. Lean mass and fat mass were measured using bioelectrical impedance analysis. LV structure was assessed via CMR, with LV mass, LV end-diastolic volume (LV EDV) and LV mass:volume ratio being calculated using CMRtools. The associations between the various measures of body composition and LV structure were assessed in multiple linear regression models, adjusted for age, blood pressure, gender and height. Results: Lean mass is the strongest predictor of LV mass (β=0.55, p 0.05). However, there were significant gender differences in the association between adiposity and LV mass and volume. Fat mass had a significant, positive association with LV mass for women (β=0.18, p=0.03) but not for men (β= -0.06, p=0.50). Similar results were seen for the association between LV EDV and fat mass (women: β=0.21, p=0.01; men: β= -0.07, p=0.40). In contrast, fat mass had no significant association with LV mass:volume ratio in either sex (women: β=0.07, p=0.47; men: β= -0.02, p=0.87). Conclusions: In a population without traditional cardiovascular risk factors, greater adiposity is associated with greater LV mass and LV dilatation (i.e. eccentric hypertrophy) in women but not in men. However, there was no relationship between adiposity and concentric hypertrophy (LV mass:volume ratio) in either sex. These findings may be due to biological factors specifically associated with female adiposity.

Fatty acid binding protein 4 predicts left ventricular mass and longitudinal function in overweight and obese women

ObjectiveTo explore whether increased adipocyte-derived serum fatty acid binding protein 4 (FABP4) predisposes to cardiac remodelling and left ventricular dysfunction in human obesity.DesignCross-sectional investigation.SettingAcademic clinical research centre.Patients108 overweight and obese...

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

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

Echocardiographic evaluation of changes in left ventricular size and valvular regurgitation associated with physical training during and after maturity in Standardbred trotters

To assess whether physical training induces cardiac hypertrophy and valvular regurgitation in maturing Standardbred trotters and to establish a prediction model for the size of the left ventricle. Longitudinal observational study. 53 Standardbred trotters. Each horse underwent 2-D, M-mode, and color flow Doppler echocardiography at 5.5 years of age; previously, each horse had been examined at 2, 2.5, 3, and 3.5 (time of maturity) years of age. Horses were or were not in training or racing for variable periods during the entire assessment period; data for a given horse were assigned to 1 of 2 groups on the basis of the horse's status at the fifth examination (racing [n = 40] or not racing [13]). At each examination, left ventricular (LV) internal diameter in diastole (LVIDd), LV mass, and mean and relative LV wall thicknesses were measured. Prevalence and severity of tricuspid, pulmonary, mitral, and aortic valve regurgitation were determined. During the assessment period, LVIDd, LV mass, and mean LV wall thickness increased; body weight was significantly associated with those variables. Prediction of LV mass was possible when sex and weight were included in the model. Prevalence of valvular regurgitation increased for all valves. An increased risk of development of tricuspid and pulmonary valve regurgitation for horses in racing was observed. The LV mass and prevalence of valvular regurgitation increased (indicative of development of exercise-induced cardiac hypertrophy and valvular regurgitation) in young horses, even during the latter part of the assessment period, when maturity was attained.

Obesity and daytime pulse pressure are predictors of left ventricular hypertrophy in true normotensive individuals

To investigate predictors of left ventricular mass corrected for height2.7 (LVMI) and left ventricular hypertrophy in patients who were found to be normotensive with both office and 24-h ambulatory blood pressure (BP) measurements. A total of 805 consecutive patients were analyzed. All patients underwent office BP measurements, 24-h ambulatory BP monitoring, laboratory measurements for cardiovascular risk factors and echocardiography. Individuals with both office and ambulatory normotension were characterized as true normotensive. LVMI was found to be 34.5 +/- 10.9 g/m2.7 in normal-weight patients and 48.7 +/- 13.0 g/m2.7 in obese patients (P < 0.0001). LVMI was found to be 41.7 +/- 10 g/m2.7 in overweight patients, significantly lower than the values of obese patients (P < 0.005) and higher than the values of normal-weight patients (P < 0.001). These results remained significant even after adjustment for age, sex, daytime and nighttime SBP, daytime and nighttime DBP, daytime and nighttime BP variability and daytime and nighttime pulse pressure (PP). In a multivariate analysis model, in which LVMI was the dependent variable and office SBP, office DBP, daytime and nighttime SBP and DBP, daytime and nighttime PPs and variabilities, day-night SBP ratio, fasting serum glucose, triglycerides, total cholesterol, age and BMI were inserted as independent variables with weighted least squares regression by sex, the predictors of LVMI were age, BMI and daytime PP (r2 = 0.31). Left ventricular hypertrophy was 17.67 times more likely in obese patients as compared with normal-weight true normotensive individuals. Obesity may represent a significant cardiovascular risk factor even in normotensive individuals. Other predictors of LVMI were ageing and daytime PP.

The electrocardiogram in left ventricular hypertrophy: past and future

The electrocardiographic diagnosis of left ventricular hypertrophy (LVH) has been centered on improving the diagnostic sensitivity and specificity of the method, using criteria whose precise relationship to increased left ventricular mass are not established. Although the electrocardiogram (ECG) has been displaced to a secondary role in the prediction of left ventricular mass, ECG/LVH has been shown to be a strong predictor of morbidity and early mortality. There are strong clues that each of the parameters in ECG/LVH is related to cardiac contractility and ejection. It is suggested that research be redirected to an exploration of these relationships and predicted that this will lead to both a better understanding of this venerable tool and an improvement in its usefulness to the clinician and patient.

Effects of Body Size and Body Fatness on Left Ventricular Mass in Children and Adolescents: Project HeartBeat!

Left ventricular mass (LVM) is a strong predictor of cardiovascular disease in adults. Available study findings on effects of body fatness on LVM in children are inconsistent. Understanding the impact of body fat on LVM in children may help prevent excessive LVM through measures to reduce overweight and obesity. Healthy children (n=678) aged 8, 11, and 14 years at baseline were examined at 4-month intervals for up to 4 years (1991-1995); 4608 valid measurements of LVM were obtained with M-mode echocardiography. A multilevel linear model was used for analysis. The impact of body size was examined by adding separately nine body-size indicators to a basic LVM-gender-age model. The impact of body fatness was tested by introducing four body-fatness indicators into the nine models, yielding 36 models. All body-size indicators showed strong, positive effects on LVM. In models containing weight or body surface area (measuring both fat-free and fat contributions to body size), additional effects of body fatness were negative; in models containing fat-free mass (FFM) or height (both measuring body size independent of body fat), increased body fatness was related to a significant increase in LVM. For example, in models with FFM as a body-size indicator, a 1-SD increase in percent body fat or fat mass was related to a 5.4- or 7.2-g increase in LVM, respectively. Effects of body size on LVM attributable to fat-free body mass can be distinguished from those attributable to fat body mass; both are independent, positive predictors, but the former is the stronger determinant. When a body-size indicator not independent of body fat is used as a predictor, effects of fat-free body mass and fat body mass are forced to relate to the same indicator; because their magnitudes are estimated to be equal, the effect of fat body mass is overestimated. Thus, when an additional body-fatness indicator is included in the prediction of LVM, the additional estimated effect related to the indicator appears to be negative.