Left Ventricular Hypertrophy Evaluation in Obese Hypertensive Patients: Effect of Left Ventricular Mass Index Criteria

Abstract

Purpose -To evaluate left ventricular mass (LVM) index in hypertensive and normotensive obese individuals. Methods -Echocardiographic evaluation of hypertensive individuals is based on preestablished guidelines for detecting left ventricular hypertrophy, determined in relation to populations of normotensive individuals. In turn, the definition of normal left ventricular mass implies its correction by influencing physiological factors. Thus, sex, body habitus, and possibly age are of importance in this correction.The best index of left ventricular mass is that obtained using the physiological scale of weight and height variables, regarding both men and women.Therefore, the ideal index would be lean body mass 1 , but this method is not practical and has not been used. Thus, indexing ventricular mass by body surface area (BSA) is preferred 2 . However, such an index leads to underestimation of left ventricular hypertrophy in obese individuals (with a greater BSA), because its regards obesity as a continuous physiological variable that would determine increases in left ventricular mass also on a physiological scale 3 . To correct this, use of mass by height, whose limits are within the physiological range and thus maintain a normal and not a pathological relation to ventricular mass, has been proposed as an index [4][5][6] . More recent studies 7-11 further suggest that left ventricular mass index should be determined by height or even height raised to a power of 2, 2.7, or 2.13, because no first order relation has been demonstrated between height and left ventricular mass.In this sense, some selection criteria have been established that have been used for the correction of mass by these proposed indexers (men -126/143g/m; 49.2g/m 2.7 ; women -105/102g/m; 46.7g/m 2.7 )4,11 . Such criteria, up to the present, have preferentially been used in larger population studies 11,[13][14][15][16] with the purpose of detecting the impact of the different indexes used on the prevalence of

Left-ventricular hypertrophy and obesity

“…According to criteria based on left-ventricular mass indexed to BSA, LVH prevalence ranged from 22.0 [27] to 67.0% [21]; the corresponding figures for left-ventricular mass indexed to height 2.7 were 20.0 [17] and 85.0% [32]. A meta-analysis aimed at comparing the prevalence of LVH in normotensive (six studies, 418 participants) [17][18][19]26,31,35] and hypertensive obese individuals (eight studies, 1976 participants) [15,16,21,22,28,29,32,33], and failed to find significant difference between the groups (54 versus 59%; P ¼ 0.44).…”

“…Fifteen out of 22 studies [15][16][17][18][20][21][22][23][25][26][27][28][29]31,32] provided data on LVH prevalence in obese (n ¼ 4999) as compared to non-obese controls (n ¼ 6623). As reported in Fig.…”

Evaluation of Echocardiography as a Marker of Cardiovascular Risk in Obese Children and Adolescents

“…In a study on 544 essential hypertensive, 173 men and 371 women ages ringing from 13 to 84 years and 17 to 80 years respectively, and 106 normotensive individuals, Rosa et al [19], using an M mode echocardiogram and LV mass indexed according to body surface (LV mass/body surface area) and to height squared (LV mass/height 2 ), compared the two LV mass indices in the two populations stratified according to BMI. However, indexing by body surface area did not show significant differences between subgroups, whereas indexing by height squared showed significantly greater differences according to the increase in BMI in the hypertensive and normotensive populations.…”

Effect of Body Mass Index on Left Ventricular Mass

“…Despite these known relationships,current use of noninvasive tools tends to underestimate the presence of increased left ventricular thickness, particularly among these individuals as noted in previous reports (15). Echocardiography has consistently been the most accurate non-invasive method for assessing left ventricular wall thickness in hypertensive individuals (16).…”