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Ref 1Ages 6-23 y/oSignificant LVM differences by gender – For males 95th percentiles:LVM/BSA = 103LVM/height = 100For females 95th percentiles:LVM/BSA = 84LVM/height = 81Ref 2Ages 6-17 y/oSignificant LVM differences by gender – males avg 99 g, females avg 80 gAcross races and genders - Indexing by LV mass /height **3 provided the best correlation with LV mass/lean body mass compared to indexing withBSAHeightHeight **2Height ** 2.7For entire group (all races and genders) 95th percentiles:LVM/BSA = 89LVM/height = 85LVM/height **2 = 52LVM/height **2.7 =39LVM/height**3 = 34Ref 3The method of correcting LVM for body size and the criteria used to define LVH have varied between studiesBecause of the rise in the prevalence of obesity, indexing of LVM to weight or body surface area may allow an increased LVM to be interpreted erroneously as normal. Height2.7 (in meters) has been validated as an indicator of lean body mass and has been recommended for indexing LVM. Use of height2.7 to index LVM also minimizes the effect of age, gender, and race.10,11LVH by adult criteria was defined as LVMI > 51 g/m2.7 and by pediatric criteria as LVMI > 38.6 g/m2.7.Ref 4 See graphRef 5Adult values See TableWomen LVM/BSA < 95Men LVM/BSA < 115Ref 6 ASE Peds Quantification paper – Not much help.Ref 7 (agrees with Ref 3)241 adults and 444 infants to young adultsNormalizations of left ventricular mass for height or body surface area introduce artifactual relations of indexed ventricular mass to body size and errors in estimating the impact of overweight. These problems are avoided and variability among normal subjects is reduced by using left ventricular mass/height**2.7Ref 8Scaling LV mass to BSA in children results in less misclassification with respect to LVH than does scaling to height.Ours is not the first study to conclude that height based LV mass normalization results in overestimation of the prevalence of LVH among the obese.Ref 9A number of controversies surround the measurement of LV mass. There are significant problems in standardizing echocardiographic measurement of LV mass across echocardiography laboratories. Historically, one method for overcoming this variability in adults is to index the LV mass to body size, most commonly BSA, height in meters squared, or to the 2.7th power [10]. Dividing LV mass by height to the power of 2.7 accounts for LV mass and scaling myocardial mass to body size. This useful application has been adapted in children to compensate for normal growth [11]. However, this indexing method is also limited in the pediatric population because LVMI2.7 increases with decreasing height [7]. Numerous studies have shown that LVMI2.7 overestimates LV mass in adults [5]. Foster et al. [9] showed that expressing LV mass relative to BSA or height has limitations in the pediatric population because LV mass varies in proportion to lean body mass; however scaling LV mass to BSA in children appears to be better than scaling to height.Ref 10The children and adolescents who have elevated BMI (overweight and obese) with NWC (normal waist circumference) had LVM and LBM similar to normal controls with NWC despite having an elevated BMI and elevated non-LBMI (as an estimation of adipose tissue). Additionally, similar to normal controls, those subjects with elevated BMI and NWC had a stronger correlation between LVM and LBM than subjects with elevated BMI with IWC (increased waist circumference).ReferencesS. Daniels, et al. Echocardiographically Determined Left Ventricular Mass Index in Normal Children, Adolescents, and Young Adults J Am Coll Cardiol 1988;12:703-8S. Daniels, et al. Indexing Left Ventricular Mass to Account for Differences in Body size… Am J Cardiol 1995;76:699-701.Hanevold C, The Effects of Obesity, Gender, and Ethnic Group on Left Ventricular Hypertrophy and Geometry in Hypertensive Children: A Collaborative Study of the International Pediatric Hypertension Association. Pediatrics 2004;113:328 –333.Cain PA. et al. Age and gender specific normal values of left ventricular mass, volume and function for gradient echo magnetic resonance imaging: a cross sectional study. BMC Medical Imaging. 1471-2342/9/2.ASE Recommendations for Chamber Quantification: A Report from the American Society of Echocardiography’s Guidelines and Standards Committee and the Chamber Quantification Writing Group, Developed in Conjunction with the European Association of Echocardiography, a Branch of the European Society of Cardiology. JASE 2005 Vol 14;12:1440-1463.ASE Recommendations for Quantification Methods During the Performance of a Pediatric Echocardiogram: A Report From the Pediatric Measurements Writing Group of the American Society of Echocardiography Pediatric and Congenital Heart Disease Council. JASE 2010;23:465-95.De Simone G, et al. Left Ventricular Mass and Body Size in Normotensive Children and Adults: Assessment of Allometric Relations and Impact of Overweight. J Am Coli CardioI1992;20:1251-60Foster et, al Limitations of expressing LV mass relative to height and to BSA in children. JASE 2013;26:410-8.Mirchandani D, et al. Concordance of measures of left-ventricular hypertrophy in pediatric hypertension Pediatric Cardiology, Pediatr Cardiol. 2014 Apr;35(4):622-6. doi: 10.1007/s00246-013-0829-7. Epub 2013 Nov 20.? Am J Cardiol. 2014 Mar 15;113(6):1054-7. doi: 10.1016/j.amjcard.2013.11.068. Epub 2013 Dec 25. Left ventricular mass in children and adolescents with elevated body mass index and normal waist circumference. Mehta SK. ................
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