Abstract-We have recently observed that in patients with end-stage renal disease (ESRD) raised plasma norepinephrine (NE) is an independent predictor of incident cardiovascular events but that its prognostic power is reduced when this sympathetic marker is tested in statistical models including also left ventricular mass. Because left ventricular hypertrophy (LVH) may be a mechanism whereby NE contributes to the high rate of cardiovascular events in ESRD, we examined the relationship between plasma NE and echocardiographic parameters of left ventricle mass in a large group of ESRD patients. Mean wall thickness (MWT) was higher in patients in the third NE tertile than in the other 2 tertiles (Pϭ0.001), and such an increase was paralleled by a rise in relative wall thickness (RWT) (Pϭ0.006).Concentric LVH was more prevalent in patients in the third NE tertile (46%) than in the second (38%) and first (25%) NE tertiles. Multivariate regression analysis confirmed that the association of plasma NE with the muscular component of left ventricle (MWT) and with RWT was independent (PՅ0.001) of other cardiovascular risk factors, and in these models, plasma NE ranked as the second correlate of MWT and RWT. Similarly, multiple logistic regression analysis showed that the association of plasma NE with concentric LVH was strong and again independent of other risk factors (Pϭ0.003). Plasma NE is associated to concentric LVH in ESRD patients. These observations constitute a sound basis for testing the effect of anti-adrenergic drugs on left ventricle mass and on cardiovascular outcomes in patients with ESRD. Key Words: cardiovascular risk Ⅲ dialysis Ⅲ left ventricular hypertrophy Ⅲ norepinephrine Ⅲ renal failure Ⅲ sympathetic activity Ⅲ uremia A t least 3 prospective studies have coherently demonstrated that raised left ventricular mass (LVM) has a strong negative prognostic impact in patients with end-stage renal disease (ESRD), 1-3 and on this basis, left ventricular hypertrophy (LVH) is now considered a major cardiovascular risk factor in these patients. The pathogenesis of LVH is multifactorial, and several causative factors have been identified-including hypertension, anemia, hyperparathyroidism, and chronic volume expansion 4 -but these factors only in part account for the high prevalence of this alteration in patients with ESRD. Sympathetic activity measured by sympathetic nerve microneurography is increased in patients with mild to moderate renal dysfunction 5 and in those with ESRD,6 and high sympathetic tone is considered a major player in the pathogenesis of hypertension in renal diseases. 7,8 Although sympathetic overactivity is being suspected as a likely mechanism responsible for the high cardiovascular morbidity and mortality in patients with chronic renal diseases, to our knowledge there is no study linking raised norepinephrine (NE) to alterations in left ventricular mass in these patients.In a large cohort of dialysis patients, we have recently observed that raised plasma NE is a strong and independent predicto...