Left ventricular hypertrophy, cardiac remodeling and asymmetric dimethylarginine (ADMA) in hemodialysis patients

Background. The endogenous inhibitor of nitric oxide (NO), asymmetric dimethylarginine (ADMA), is a strong predictor of adverse cardiovascular outcomes in patients with end-stage renal disease (ESRD). Methods. Since arterial and cardiac remodeling is associated with altered endothelial microcirculatory responses to forearm ischemia (a NO-dependent response), interference of ADMA with the NO system may be important for the pathogenesis of left ventricular hypertrophy (LVH) in these patients. This study sought to identify the relationship between plasma ADMA and LV geometry and function in a cohort of 198 hemodialysis patients. Results. Plasma ADMA was significantly higher (P = 0.008) in patients with LVH (median 3.00 μmol/L, inter-quartile range 1.73 to 3.97 μmol/L) than in those without this alteration (1.88 μmol/L, 1.15 to 3.56 μmol/L) and was significantly related to left ventricular (LV) mass (r = 0.26, P < 0.001). Interestingly, ADMA was much higher (P < 0.001) in patients with concentric LVH (3.60 μmol/L, 2.90 to 4.33 μmol/L) than in patients with eccentric LVH (2.17 μmol/L, 1.47 to 3.24 μmol/L) or normal LV mass (1.76 μmol/L, 1.13 to 2.65 μmol/L). Furthermore, plasma ADMA was higher (P = 0.02) in patients with systolic dysfunction (3.52 μmol/L, 2.08 to 5.87 μmol/L) than in those with normal LV function (2.58 μmol/L, 1.53 to 3.84 μmol/L) and inversely related to ejection fraction (EF; r = -0.25, P < 0.001). The link between ADMA and LV mass and EF was confirmed by multivariate analysis (ADMA vs. LVMI, β = 0.17, P = 0.006; ADMA vs. EF, β = -0.24, P < 0.001). Conclusions. Overall, this study indicates that raised plasma concentration of ADMA is associated to concentric LVH and LV dysfunction. Intervention studies are needed to see whether the link between ADMA and concentric LVH remodeling and LV dysfunction is a causal one.