![]() The first and most commonly used echocardiography method of LVM estimation is the linear method, which uses end-diastolic linear measurements of the interventricular septum (IVSd), LV inferolateral wall thickness, and LV internal diameter derived from 2D-guided M-mode or direct 2D echocardiography. Regardless of the method used, LVM estimation is derived by converting myocardial volume to mass by multiplying the volume by the myocardial density of 1.05 g/mL. Echocardiography offers a reliable, noninvasive, rapidly available, and relatively inexpensive method for estimation of LVM. Given the clinical importance of LVM, it is essential to have a reliable method for its estimation. 14Įchocardiography LVM Measurements Method and Comparison to Cardiovascular Magnetic Resonance (CMR) 20 BSA has been widely adopted by the American Society of Echocardiography (ASE) and European Association of Cardiovascular Imaging as the preferred method for indexing LVM. 15 In a population with a low prevalence of obesity, there was no significant difference in the risk attributed to LVH regardless of the method of indexation. demonstrated that indexation to LVM/height 1.7 was the best method, in comparison to BSA and height 2.7, to identify obesity-related LVH and was more consistently associated with CVD outcomes and all-cause mortality. 15,18-20 Indexation of LVM to height raised to an allometric exponent of 2.7 (LVM/height 2.7), in comparison to BSA or height alone, has shown better predictive value for CVD outcomes, better detection of obesity-related LVH, and less variability of LVM among normal individuals. 18 Consequently, height has also been used for indexing (either height alone or height raised to an allometric power of 1.7 or 2.7). 17 However, indexing by BSA has been noted to minimize the effect of obesity on LVM, and, therefore, it underestimates the prevalence of obesity-related LVH. 14 However, there is controversy about the best method for indexing LVM.īody surface area (BSA) was the first anthropometric variable used to index LVM and has shown a stronger statistical correlation than height with LVM 16 and better identification of hypertension-related LVH. 12,15 In order to allow comparison of LVM among subjects of different body sizes, different allometric approaches have been suggested to normalize LVM. 12,14 Separate cutoff values for body size-adjusted LVM have been used for men and women. Normal values for LVM are derived from studies of the general population without hypertension or obesity. Other factors to be considered are age and blood pressure. 12 Consequently, LV relative wall thickness (RWT), defined as the ratio of twice the LV inferolateral wall thickness to the LV internal diameter measured at end-diastole, initially remains unchanged. ![]() The aforementioned body size-, ethnic-, and exercise-related factors are associated with increased LVM, as well as proportional increases in left ventricular (LV) volume, which initially maintains normal LV wall stress. 11,13 Likewise, obesity is associated with increased LVM. 11 Similarly, athletes have increased LVM compared to nonathletes, 12 and black men and women have larger LVM than their white or Asian counterparts. ![]() However, even after adjustment for anthropometric variables, males have larger LVM than females. 4,8 Moreover, the regression of LVH in patients with hypertension treated with antihypertensive medication, or after aortic valve replacement in patients with severe aortic valve stenosis, has been associated with improved CVD outcomes. 7 Therefore, LVM has been touted as a suitable measure for CVD risk stratification and a marker for subclinical disease. 5 Additionally, a low traditional CVD risk profile in young adults has been associated with lower LVM and, consequently, lower CV morbidity and mortality. 4 Similarly, in the Cardiovascular Health Study's elderly cohort, the multiple-risks-adjusted hazard ratio for the highest quartile of gender-specific LVM was 3.36 compared to the lowest quartile. ![]() 4-6 In the pioneering Framingham Heart Study, after adjusting for age and traditional risk factors, the relative risk for coronary disease per 50 g/m increment in LVM was 1.67 in men and 1.60 in women. 1-3 Population-based studies have revealed that increased LVM and left ventricular hypertrophy (LVH) as assessed by two-dimensional (2D) M-mode echocardiography measurements provide prognostic information beyond traditional cardiovascular disease (CVD) risk factors. Left ventricular mass (LVM) is a well-established measure that can independently predict adverse cardiovascular events and premature death. ![]()
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