Association between left ventricular mass index and cardiac function in pediatric dialysis patients

Abstract

Left ventricular mass index (LVMI) is a surrogate of left ventricular hypertrophy and a predictor of cardiac morbidity and mortality in adults with hypertension. LVMI has not been linked to cardiovascular endpoints in children. The aim of this study was to identify an association between elevated LVMI and echocardiographic markers of systolic and diastolic function. The study was a retrospective review of chronic dialysis patients from June 1995 to December 2009 at a single tertiary care children's hospital. The upper limit cutoffs for LVMI were set at >38.6 g/m(2.7), >51 g/m(2.7), and by age and sex-based normative values. Sixty-three patients (mean age 14.1 years, 56% males) were enrolled in the study, with a total of 287 echocardiograms. Post-dialysis hypertension was associated with elevated LVMI in both the >51 g/m(2.7) [odds ratio (OR) 2.9, 95% confidence interval (CI) 1.5-5.5] and normative (OR 3.4, 95% CI 1.5-7.7) models. Elevated LVMI, when defined by the >51 g/m(2.7) and normative models, was significantly associated with decreased shortening fraction (OR 4.1, 95% CI 1.7-9.8 and OR 5.4, 95% CI 1.3-22.9, respectively) and increased mitral E wave to lateral mitral tissue Doppler e' wave velocity ratio (E/e'; OR 3.5, 95% CI 1.1-11.2 and OR 4.5, 95% CI 1.0-21.6, respectively). Elevated LVMI is associated with decreased systolic and diastolic cardiac function, justifying its use as a surrogate of hypertensive cardiomyopathy in children undergoing chronic dialysis.