Determinants Of Left Ventricular Mass Research Articles

Sex-Specific Determinants of Left Ventricular Mass in Pre-Diabetic and Type 2 Diabetic Subjects

Obesity and hypertension are regarded as the most important determinants of left ventricular mass in the community. Little is known about sex-specific influences of obesity, hypertension, and other risk factors on left ventricular mass in pre-diabetic or diabetic subjects. We examined how body composition, blood pressure, and other factors are related to left ventricular structure in elderly subjects (mean age 62 years, 88% of women postmenopausal) with pre-diabetes (impaired fasting glucose or impaired glucose tolerance; n = 112) and diabetes with (n = 181) and without (n = 213) overt cardiovascular disease (CVD). Neither microalbuminuria nor physical activity was significantly associated with left ventricular mass. In pre-diabetic as well as diabetic subjects with CVD, mainly BMI and fat mass, particularly in women, were correlated with left ventricular mass. In the diabetic group without overt CVD, fat mass was only slightly correlated with left ventricular mass. In the latter group waist-to-hip-ratio, and, only in men, systolic blood pressure, glucose, and A1C were moderately correlated with left ventricular mass. Multiregression analysis over all groups again revealed fat mass as the main determinant of left ventricular mass in women. In women but not men obesity was associated with a significantly increased prevalence of concentric left ventricular hypertrophy. In pre-diabetic and diabetic elderly subjects fat mass is the major determinant of left ventricular mass in women but not in men. These results may partly explain sex differences in CVD mortality in obese elderly diabetic subjects and underscore the need for activities focused on weight reduction.

Relation Between Number of Component Views and Accuracy of Left Ventricular Mass Determined by Three-Dimensional Echocardiography

Three-dimensional echocardiography (3DE) allows the accurate determination of left ventricular (LV) mass, but the optimal number of component or extracted 2-dimensional (2D) image planes that should be used to calculate LV mass is not known. This study was performed to determine the relation between the number of 2D image planes used for 3DE and the accuracy of LV mass, using cardiovascular magnetic resonance (CMR) imaging as the reference standard. Three-dimensional echocardiography data sets were analyzed using 4, 6, 8, 10 and 20 component 2D planes as well as biplane 2D echocardiography and CMR in 25 subjects with a variety of LV pathologies. Repeated-measures analysis of variance and the Bland-Altman method were used to compare measures of LV mass. To further assess the potential clinical impact of reducing the number of component image planes used for 3DE, the number of discrepancies between CMR and each of the 3DE estimates of LV mass at prespecified levels (i.e., > or =5%, > or =10%, and > or =20% difference from CMR LV mass) was tabulated. The mean LV mass by magnetic resonance imaging was 177 +/- 56 g (range 91 to 316). Biplane 2-dimensional echocardiography significantly underestimated CMR LV mass (p <0.05), but LV mass by 3DE was not statistically different from that by CMR regardless of the number of planes used. However, error variability and Bland-Altman 95% confidence intervals decreased with the use of additional image planes. In conclusion, transthoracic 3DE measures LV mass more accurately than biplane 2-dimensional echocardiography when > or =6 component 2D image planes are used. The use of >6 planes further increases the accuracy of 3DE, but at the cost of greater analysis time and potentially increased scanning times.

Waist Circumference May be More Important than Body Mass Index (BMI) in Determinants of Left Ventricular Mass in Korean Hypertensive Patients

Background: In many studies, obesity is highly correlated with adverse coronary risk profile. Increased left ventricular (LV) mass is an independent risk factor for cardiovascular mortality and morbidity. Hypertension is an well known factor related with LV mass. Obesity also is related with LV mass and commonly associated with hypertension. However, few data are available concerning the relations of LV mass to central obesity, especially in Korean hypertensive patients. So, this study was to evaluate the significance of waist circumference in determinants of LV mass in Korean hypertensive patients. Methods: A total of 74 hypertensive [40 women, 34 men; mean age, 62.5 years; mean body mass index (BMI), 25.0 kg/m2, 17 with type 2 diabetes] patients without prevalent cardiovascular disease were studied. Echocardiographic LV septal thickness, LV posterior wall thickness, LV dimension and LV mass were analysed. Results: LV mass, diastolic left ventricular internal dimension and epicardial fat thickness were larger in men than in female. LV mass was larger in obese patients defined by body mass index and also in central obese patients defined by waist circumference. LV mass was correlated with sex, body mass index, waist circumference, diastolic left ventricular internal dimension, left ventricular posterior wall thickness and interventricular septal thickness. After controlling for age, sex and body mass index, waist circumference was correlated with LV posterior wall thickness and LV mass. Conclusion: Waist circumference may be more important than BMI in determinants of left ventricular mass in Korean hypertensive patients. (J Kor Diabetes Assoc 31:130~135, 2007)

Contrast-enhanced echocardiography improves agreement on the assessment of ejection fraction and left ventricular function. A multicentre study

Analysis of global and regional left ventricular function has important therapeutic and prognostic implications 1–3. Several imaging modalities are used to define left ventricular function and left ventricular volumes as well as regional function, among them echocardiography, cineventriculography, radionuclide ventriculography and magnetic resonance imaging (MRI). Cardiac MRI has evolved in recent years as the gold standard for determination of left ventricular mass, volumes and left ventricular function owing to the high image quality allowing clear endocardial and epicardial border definition in volumetric data sets 4,5. Echocardiography is the most frequently used modality in clinical practice to define global and regional left ventricular function. Limited endocardial border definition with subsequent moderate reproducibility and accuracy are the major limitation of 2-D echocardiography. Contrast echocardiography in combination with recent innovations in ultrasound technology like Harmonic Imaging has been shown to significantly improve endocardial border delineation especially in patients with difficult imaging conditions which was unattainable before 6–8. The SonoVue LV Function Group evaluated in a European multicentre study consisting of two parts the utility of contrast-enhanced echocardiography for assessment of global and regional left

Different Impact of the Metabolic Syndrome on Left Ventricular Structure and Function in Hypertensive Men and Women

Metabolic syndrome (MS) is increasingly recognized as an important cardiovascular risk factor in hypertension, but its influence on left ventricular (LV) mass and function in the 2 genders has not been specifically addressed. Among 618 nondiabetic, untreated hypertensive subjects, echocardiographically detected LV mass was significantly greater in subjects with MS. A significant interaction was observed between sex and the MS (P<0.003 for the multiplicative interaction term). Compared with women without the MS, those with the syndrome had a 24% greater LV mass (49.5+/-12 versus 40.0+/-10 g x m(-2.7); P<0.001), whereas the difference was only 9% in men (50.3+/-12 versus 46.1+/-10 g x m(-2.7); P=0.003). A greater prevalence of LV hypertrophy was found in women (37% versus 14%; P<0.001) but not in men (39% versus 29%; P=0.09) with the MS. After adjustment for the effect of age, body mass index, 24-hour systolic blood pressure, and several confounders, the MS was independently associated with a greater LV mass index in women (regression coefficient, 4.80; P<0.001) but not in men. Women with the MS also had a greater LV relative wall thickness (0.42+/-0.07 versus 0.39+/-0.07; P=0.004) and a depressed afterload-corrected midwall fractional shortening (94.0+/-12% versus 101.0+/-13%; P<0.001) than women without the syndrome, whereas no differences emerged in men. We conclude that, in untreated hypertension, MS has a different impact on LV hypertrophy and function in men and women. The effect of MS is more pronounced in women and is partly independent from the effect of several hemodynamic and nonhemodynamic determinants of LV mass.

Whole Blood Cardioplegia (Minicardioplegia) Reduces Myocardial Edema After Ischemic Injury and Cardiopulmonary Bypass

While blood:crystalloid cardioplegia is the clinical standard for patients undergoing cardiopulmonary bypass (CPB), it has been postulated that whole blood minicardioplegia may benefit the severely injured heart by reducing cardioplegic volume, thereby reducing myocardial edema. To test this hypothesis, we compared the cardioprotection of a popular 4:1 blood:crystalloid cardioplegia to whole blood minicardioplegia (WB) in a porcine model of acute myocardial ischemia. Yorkshire pigs (n = 20) were placed on atriofemoral bypass and subjected to 30 minutes of global normothermic ischemia. Animals were randomized to receive either 4:1 cold cardioplegia (n = 10) or WB cold cardioplegia (n = 10) delivered antegrade continuously for 90 minutes. Baseline (BL) echocardiographic determination of left ventricular mass (LVM) was compared within groups for cardiac edema (%) measured by histologic morphometrics. All (100%) animals receiving WB were successfully weaned off CPB, whereas only 40% of animals receiving 4:1 were successfully weaned off CPB. Cardiac edema percentage (p &lt; .004) and LVM (p &lt; .05) were significantly decreased in the WB group compared with 4:1. WB cardioplegia increases the number of hearts successfully weaned from CPB and decreases cardiac edema in our porcine model of acute myocardial ischemia. This finding implies whole blood cardioplegia may be more protective in a select group of patients undergoing extended CPB time by decreasing myocardial edema.

Sex-Related Differences in the Relations of Insulin Resistance and Obesity to Left Ventricular Hypertrophy in Japanese Hypertensive Patients

Echocardiographically determined left ventricular (LV) hypertrophy is a powerful, independent predictor of cardiovascular morbidity and mortality. Both insulin resistance and obesity have a well-known association with LV hypertrophy. However, whether or not there are sex-related differences in the relations of insulin resistance and obesity to LV hypertrophy has never been systematically explored in Japan. We enrolled 91 never-treated hypertensive patients (49 men and 42 women) to assess the possible relations of insulin resistance and obesity to LV geometry. Insulin resistance was estimated using the homeostasis model assessment (HOMA) formula. Echocardiographically determined LV mass and relative wall thickness were measured as markers of LV geometry. In addition, body mass index (BMI) was calculated as weight (kg) divided by height (m)2 as a marker of obesity. Independent determinants of LV mass in male hypertensive patients were HOMA value (p < 0.0001) and age (p = 0.034). BMI did not bear a significant relation to LV mass. In comparison, in female hypertensive patients BMI was an independent determinant of LV mass (p = 0.011). The HOMA value did not bear a significant relation to LV mass in the female hypertensive patients. In conclusion, these findings indicate the presence of sex-related differences in the relations of insulin resistance and obesity to LV hypertrophy in Japanese hypertensive patients. The effect of obesity on LV geometry was greater in female hypertensive patients than in male hypertensive patients.

Caution for Winter Morning Surge in Blood Pressure

morning systolic BP measured on standing minus systolic BP before rising. Although there were no significant differences in the 24-hour BP levels between each group, cardiovascular complications occurred more frequently during the follow-up period in the higher quartile groups. In the multivariate analysis, the waking morning BP surge was significantly associated with cardiovascular risk independent of age and 24-hour BP level. Morning BP surge is also significantly associated with hypertensive target organ damage. In the JMS ABPM study (Wave 1), silent cerebral infarct was measured by brain MRI at baseline and was more frequently detected in the morning surge group than in the nonsurge group, particularly multiple silent cerebral infarcts.4 Exaggerated morning BP surge also appeared to increase hypertensive heart disease. In our community-dwelling subjects, sleep-rough surge adjusted for morning physical activity was significantly correlated with left ventricular (LV) mass index, assessed by echocardiography,6 as found in the French study.5 Morning BP minus evening BP assessed self-measured BP, also independent determinants of LV mass in hypertensive patients. 7 In addition, hypertensive patients with morning BP surge had prolonged corrected QT interval (QTc) duration and QTc dispersion compared with those without morning BP surge.8 These QTc abnormalities found in the morning BP surge groups were only significant in the morning period. Spectral analysis of heart rate variability showed that the low frequency power/high frequency power ratio, an indirect index of sympathetic activity, was significantly higher in the morning BP surge group than in the nonsurge group. Thus, in the surge groups, increased sympathetic activity in the morn

Physiological determinants of the variation in left ventricular mass from early adolescence to late adulthood in healthy subjects

The physiological determinants of left ventricular mass (LVM) measured by cardiac magnetic resonance (CMR) imaging are not well defined as prior investigators have studied either adults or adolescents in isolation or have not strictly excluded hypertension or accounted for the effects of exercise habits, haemodynamic, demographic, or body shape characteristics. A total of 102 healthy volunteers (12-81 years, 53 males) underwent CMR. All parameters [unstandardized and adjusted for body surface area (BSA)] were analysed according to gender and by adolescence versus adulthood (adolescents <20 years, adults > or = 20 years). The influence of haemodynamic factors, exercise, and demographic factors on LVM were determined with multivariate linear regression. LVM rose during adolescence and declined in adulthood. LVM and LVMBSA were higher in males both in adults (LVM: 188 +/- 22 g versus 139 +/- 21 g, P < 0.001; LVMBSA: 94 +/- 11 g m(-2) versus 80 +/- 11 g m(-2), P < 0.001) and in adolescents when adjusted for BSA (LVM: 128 +/- 29 g versus 107 +/- 20 g, P = 0.063; LVMBSA: 82 +/- 8 g m(-2) versus 71 +/- 10 g m(-2), P = 0.025). In adults, systolic blood pressure (SBP) and self-reported physical activity increased while meridional and circumferential wall stress were constant with age. Multivariate regression analysis revealed age, gender, and BSA as the major determinants of LVM (global R2 = 0.69). Normal LVM shows variation over a broad age range in both genders with a rise in adolescence and subsequent decline with increasing age in adulthood despite an increase in SBP and physical activity. BSA, age, and gender were found to be major contributors to the variation in LVM in healthy adults, while haemodynamic factors, exercise, and wall stress were not.

The Accuracy of Left Ventricular Mass Determined by Real-time Three-dimensional Echocardiography in Chronic Animal and Clinical Studies: A Comparison with Postmortem Examination and Magnetic Resonance Imaging

Real-time 3-dimensional echocardiography (RT3DE), 2-dimensional echocardiography (2DE), and M-mode echocardiography were performed in 28 sheep with cardiac pathologies and 27 patients with heart disease to demonstrate the superiority of RT3DE over M-mode and 2DE for the determination of left ventricular mass. Postmortem examination and magnetic resonance imaging were used as a reference standard for the animal and clinical studies, respectively. In the animal study, the highest concordance correlation (0.92) was obtained between the actual weight of left ventricular mass and that estimated by RT3DE (0.69 for 2DE and 0.77 for M-mode, P < .001). In the clinical study, RT3DE also provided the best concordance correlation with left ventricular mass determined by magnetic resonance imaging (0.91 for RT3DE, 0.83 for 2DE, and 0.38 for M-mode; P < .0001).

Verteilung, Determinanten und Referenzwerte linksventrikulärer Parameter in der Allgemeinbevölkerung - Resultate der MONICA/KORA-Echokardiographiestudien

For successful fighting against the burden of cardiovascular disease in the community a comprehensive knowledge about the prevalence and the impact of underlying risk factors is important. The present paper summarises some studies undertaken on more than 2000 persons from the MONICA/KORA-studies (parts of S1 and S3) where left ventricular mass (LVM) and other left ventricular parameters were determined by echocardiography. We especially investigated the associations of LVM with blood pressure and obesity. A special focus was on sex-specific factors in the determination of LVM and the influence of different indices of body size when normalising LVM. It could be shown that hypertension and obesity are major determinants of LV hypertrophy. Especially women with both hypertension and obesity on showed a high prevalence of concentric hypertrophy, significantly more than men. We also showed that the prevalence of LV hypertrophy in a representative sample of the general population (25 to 74 years) is 17.5 % for men, and 18.5 % for women. This underscores the need for primary and secondary prevention regarding the development of LV hypertrophy. Finally, our data in a selected group of normal subjects (reference sample) may be used for the development of reference values for left ventricular parameters in the general German population.

Relation of genetic predisposition and insulin resistance to left ventricular hypertrophy in hypertension

The aim of the study was to determine whether genetic predisposition to hypertension and insulin resistance are related to left ventricular (LV) hypertrophy in essential hypertension. The study included 72 nondiabetic patients with essential hypertension and 15 normotensive control (NC) subjects. The 72 patients were divided into two groups according to genetic predisposition to hypertension. The family history (FH)(+) group included 33 patients with at least one essential hypertensive parent or sibling. The FH(-) group included 39 patients with weak genetic predisposition to hypertension. Insulin resistance was estimated using the homeostasis model assessment (HOMA). Echocardiographically determined LV mass (LVM) and relative wall thickness (RWT) were measured as markers of LV hypertrophy. The HOMA values in the FH(+) group (2.00 +/- 0.89) were significantly higher than those in either the FH(-) group (1.21 +/- 0.44) or NC subject group (0.91 +/- 0.24). The HOMA values in the FH(-) group were significantly higher than those in NC subjects. The LVM and RWT were greatest in the FH(+) group, followed by those in the FH(-) group and NC subjects. There were no significant differences in LVM and RWT between the FH(-) group and NC subjects. By multivariate analysis, HOMA value (P = .0011), male sex (P = .0032), body mass index (P = .0061), systolic blood pressure (P = .0245), and genetic predisposition to hypertension (P = .0441) remained determinants of LVM in nondiabetic patients with essential hypertension. Genetic predisposition to hypertension and the HOMA value appear to have additive impact on LV hypertrophy. This relation is independent of well-known determinants of LVM such as male sex, overweight, and high blood pressure.

Validation Study of Normogram For the Clinical Determination of Left Venrtricular Mass(Lvm) From M-Mode Echocardiographic Measurements in Hypertensive Heart Disease

In a study of 70 newly diagnosed hypertensive at the University of Maiduguri Teaching Hospital over a six month period, echocardiography detected increased left ventricular weight (= 225g) in 31 patients representing 44.3%. When compared with the rapid assessment of the estimation of Left Ventricular Mass (LVM) with a normogram for the clinical determination of LVM using M-mode measurement, the following indices were found: sensitivity of 61.3%, specificity of 97.4% and accuracy of 81.4%. These fairly good indices closely estimate the presence of LVM in patient with hypertensive heart disease (HHD). We therefore recommend the use of the normogram for centres without automated machines and busy specialist clinics for rapid estimation of LVM. This will improve the optimal management we render to our patients. Nig. Medical Practitioner Vol. 45(1/2) 2004: 6-8

1112-148 Two-dimensional point-to-point measurements and best slice algorithm improve accuracy of echocardiographic left ventricular mass determination: A magnetic resonance imaging correlation in humans

1112-148 Two-dimensional point-to-point measurements and best slice algorithm improve accuracy of echocardiographic left ventricular mass determination: A magnetic resonance imaging correlation in humans

Relationship between exercise systolic blood pressure and left ventricular geometry in overweight, mildly hypertensive patients.

To examine the association between the graded exercise systolic blood pressure (SBP) response and left ventricular (LV) geometric structure in patients with untreated mild hypertension. The study included 80 sedentary, overweight patients (43 female and 37 male) with unmedicated high normal blood pressure or stage 1-2 hypertension. An echocardiogram was used to determine LV mass and the relative wall thickness (RWT) in relation to the chamber dimension. Participants performed a maximal graded exercise test, and the SBP was recorded at workloads of 2, 4 and 6 metabolic equivalents and at peak exercise. Separate statistical models were used to determine the influence of LV mass indexed for height(2.7) (LVMIh) and RWT on submaximal exercise SBP and peak exercise SBP, controlling for resting SBP, age, gender, ethnicity and body mass index. A greater RWT was associated with a higher submaximal SBP level (P = 0.038). Neither LVMIh (P = 0.989) nor the interaction of RWT and LVMIh (P = 0.787) were related to the submaximal SBP. None of the main or interaction effects of RWT and LVMIh were associated with the peak exercise SBP level. Increases in RWT were associated with higher submaximal exercise SBP responses in a sample of overweight, unmedicated hypertensives. These results suggest that RWT is an important determinant of the association between cardiac mass and exercise SBP response.

Multivariate associates of QT interval parameters in diabetic patients with arterial hypertension: importance of left ventricular mass and geometric patterns.

The aim of the study was to assess the determinants of increased QT interval parameters in diabetic patients with arterial hypertension and, in particular, the strength of their relationships to echocardiographically derived left ventricular mass (LVM) and geometric patterns. In a cross-sectional study with 289 hypertensive type 2 diabetic outpatients, maximal QT and QTc (heart rate-corrected) intervals, and QT, QTc, and number-of-leads-adjusted QT interval dispersions were manually measured from standard baseline 12-lead ECGs. Electrocardiographic criteria for left ventricular hypertrophy (LVH) were either Sokolow-Lyon or Cornell sex-specific voltages. LVM and geometric patterns were determined by 2D echocardiography. Statistical analyses involved bivariate tests (Mann-Whitney, chi2, Spearman's correlation coefficients, ANOVA and receiver-operating-characteristic (ROC) curve analyses) and multivariate tests (multiple linear and logistic regressions). QT dispersion measurements showed significant correlations with echocardiographic LVM (r=0.26-0.27). ROC curves demonstrated a poor isolated predictive performance of all QT parameters for detection of LVH (areas under curve: 0.58-0.59), comparable to that of electrocardiographic voltage criteria. Only patients with concentric hypertrophy had significantly increased QT dispersion (QTd) when compared to those with normal geometries (64.24+/-21.09 vs 53.20+/-15.35, P<0.05). In multivariate analyses, both electrocardiographic and echocardiographic LVH were independent predictors of increased QTd, as well as only QTd and gender were determinants of LVM. In conclusion, increased QT interval dispersion is associated with LVM and concentric hypertrophy geometric pattern in diabetic hypertensive patients, although in isolation neither QTd nor any QT parameter presents enough predictive performance to be recommended as screening procedures for detection of LVH.

Pulsatile and steady 24-h blood pressure components as determinants of left ventricular mass in young and middle-aged essential hypertensives

In order to explore the relations between left ventricularmass (LVM) and the pulsatile (pulse pressure) andsteady (mean pressure) components of the bloodpressure (BP) curve, 304 young and middle-agedessential hypertensive patients were studied by meansof 24-h ambulatory BP monitoring and echocardio-graphy. In the overall study population, both the BPcomponents showed significant correlations with LVM.These correlations were unevenly distributed in thesubgroups of subjects younger and in those older than50 years. While in this latter subgroup, in multivariateanalysis, both 24-h mean BP (24-MBP) (b¼0.27;P¼0.008) and 24-h pulse pressure (24-h PP) (b¼0.23;P¼0.02) were associated with LVM, in the subset ofyounger hypertensives only 24-h MBP (b¼0.21;P¼0.009) was related to LVM, independent of othercovariates. The relations observed between 24-h PP andLVM in the entire study population and in the patientsolder than 50 years lost statistical significance when theeffect of 24-h systolic blood pressure (24-h SBP) wastaken into account, in a multiple regression model inwhich 24-h MBP was replaced by 24-h SBP. Our findingsseem to suggest that the association of PP with LVM inmiddle-aged hypertensives may partially explain theincreased cardiovascular risk, documented in subjectswith high PP. However, this relation is not independent,but is mediated by SBP.Journal of Human Hypertension (2003) 17, 231–238.doi:10.1038/sj.jhh.1001542Keywords: pulse pressure; mean blood pressure; ambulatory blood pressure; left ventricular mass

The genetic determination of left ventricular mass in healthy adults.

The extent to which left ventricular (LV) mass, an independent cardiovascular risk factor, is determined by genetic factors is unclear. The aim of this study was to assess the heritability of LV mass and its association with three potential candidate genes. A population-based adult twin study model was utilized. Echocardiographic assessment of LV mass was performed in 110 twin pairs (mean age 55.9+/-10.9 years). An estimate of genetic determination, heritability, was calculated for the main echocardiographic parameters. The cohort were genotyped for the G-protein beta-3, aldosterone synthase, and beta-1 adrenoceptor genes. The intra-class correlation coefficients for LV mass were 0.69 for monozygotic (r-MZ) twins and 0.32 for dizygotic (r-DZ) twins, P=0.008 (heritability estimate of 0.69). This pattern persisted following correction for known confounding factors. Within-pair differences in the monozygotic, discordant and concordant dizygotic twins showed no differences for the three genes with respect to left ventricular wall thickness or mass. There was a non-significant trend towards a relationship between LV mass and the beta-1 adrenoceptor genotype. Within a normal population left ventricular mass has a significant genetic determination. Further investigation of potential candidate genes is required.

Genetic determinants of left ventricular mass: The role of Beta-1 adrenoceptor variation in normal, athletic, and diseae populations

Genetic determinants of left ventricular mass: The role of Beta-1 adrenoceptor variation in normal, athletic, and diseae populations

P615 Determination of left-ventricular mass from contrast-echocardiography compared with magnetic resonance imaging

P615 Determination of left-ventricular mass from contrast-echocardiography compared with magnetic resonance imaging