Echocardiographically Determined Left Ventricular Mass Index in Normal Children, Adolescents and Young Adults

Abstract

Left ventricular hypertrophy is an important diagnostic and prognostic finding in children with cardiovascular disease, but there are currently no well established criteria for its determination by M-mode echocardiography. Three hundred thirty-four subjects, aged 6 to 23 years, who were free of cardiovascular disease were studied. Left ventricular mass was calculated using echocardiographic measurements in a regression equation for left ventricular mass. Intraobserver (r = 0.96, p < 0.01) and interobserver (r = 0.89, p < 0.01) variability were low. To anatomically validate the echographic formula for left ventricular mass, left ventricular measurements made at autopsy were inserted into the formula. Mass was then calculated and compared with the actual mass. There was a strong correlation between the calculated and the measured left ventricular mass (r = 0.89, p < 0.01).

Left ventricular mass was not statistically related to race, but it was strongly associated with gender (p < 0.001). It was strongly correlated with height (r = 0.82 for males, r = 0.71 for females) and body surface area (r = 0.83 for males, r = 0.74 for females). Echocardiographic criteria for left ventricular hypertrophy in children and adolescents, based on the 95th percentile, for left ventricular mass, left ventricular mass corrected for body surface area and left ventricular mass corrected for height are, respectively: 184.9 g, 103.0 g/m²and 99.8 g/m for males and 130.2 g, 84.2 g/m²and 81.0 g/m for females.

Until outcome-based standards for left ventricular hypertrophy are developed, application of gender-specific criteria derived from the distribution of left ventricular mass in a healthy population of children, adolescents and young adults is the best approach to the M-mode echocardiographic diagnosis of left ventricular hypertrophy. These standards should prove useful both in the clinical evaluation of children with cardiovascular disease and in future research.