title: Body size adjustments for left ventricular mass by cardiovascular magnetic resonance and their impact on left ventricular hypertrophy classification.
abstract: Methods to index left ventricular (LV) mass, measured by cardiovascular magnetic resonance (CMR), for body size have not been investigated. The purposes of this study were to develop allometric indices for LV mass measured by CMR and compare estimates of the prevalence and predictive value of LV hypertrophy defined by a new allometric height-weight index, LV mass/body surface area (BSA), height indices (a new allometric height index; and previously derived indices from echocardiographic measurements: LV mass/height(2), LV mass/height(2.7)), and non-indexed LV mass. 5,004 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) with CMR measurements of LV mass and no clinical cardiovascular disease at baseline were followed for a median of 4.1 years. The new indices and limits for hypertrophy (95th percentile) were derived from 822 normal-weight, normotensive, non-diabetic MESA participants. 107 events (coronary heart disease or stroke) were observed. The estimated prevalence of hypertrophy at baseline and hazard ratio for event associated with hypertrophy were 8% and 2.4 with the new allometric height-weight index, 11% and 2.2 with LV mass/BSA, 23-24% and 2.0-2.1 with height indices, and 20% and 1.7 with non-indexed LV mass. A statistically significant difference was detected between the hazard ratios based on the new height-weight index and non-indexed LV mass. The prevalence of hypertrophy is higher for indices that do not account for weight. The predictive value of hypertrophy is significantly better with the new allometric height-weight index than with non-indexed LV mass and may be better than indices without weight.
authors.affiliation: Department of Biostatistics, University of Washington, Box 357232, Seattle, WA 98195-7232, USA. lynb@u.washington.edu
authors.forename: Lyndia C
authors.initials: LC
authors.lastname: Brumback
authors.forename: Richard
authors.initials: R
authors.lastname: Kronmal
authors.forename: Susan R
authors.initials: SR
authors.lastname: Heckbert
authors.forename: Hanyu
authors.initials: H
authors.lastname: Ni
authors.forename: W Gregory
authors.initials: WG
authors.lastname: Hundley
authors.forename: João A
authors.initials: JA
authors.lastname: Lima
authors.forename: David A
authors.initials: DA
authors.lastname: Bluemke
mesh_terms: D000368:Aged; D000886:Anthropometry; D001827:Body Height; D001830:Body Surface Area; D001835:Body Weight; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000145:classification / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000208:ethnology; D016014:Linear Models; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015995:Prevalence; D012720:Severity of Illness Index; D014463:Ultrasonography; D014481:United States / Q000453:epidemiology