Abstract 5836: Renal Insufficiency Exaggerates Muscle Sympathetic Nerve Activity in Patients With Heart Failure
Backgrounds: Efferent sympathetic activity is increased in patients with chronic renal failure possibly through the mechanisms of excitatory sympathetic afferents from the damaged kidney. We examined whether renal insufficiency (RI) contributes to elevated sympathetic activity in patients with heart failure.
Methods: We determined resting muscle sympathetic nerve activity (MSNA) in 87 patients with heart failure (ejection fraction (EF) < 0.45). Estimated glomerular filtration rates (eGFR) < 60 ml/min/1.73 m2 were determined using the simplified Modification of Diet in Renal Disease equation to identify RI.
Results: Forty-three percent of the patients had RI (n=37). Mean age, gender and body mass index did not significantly differ between the RI group and no RI one. However, specific activity scale and ejection fraction were lower, usages of diuretics, beta-blockers and statins were more frequent among RI group compared with no RI one. MSNA values were significantly higher in RI group (burst rate, 53±16 vs. 46±13 bursts/minute, p < 0.05; burst incidence, 78±16 vs. 67±18 bursts/100 beats, p < 0.01). Univariate analysis showed that RI, age, specific activity scale and hemoglobin level were significant predictors of MSNA value (burst incidence). Notably, multivariate analysis revealed that RI was the only independent factor of the MSNA value.
Conclusions: These findings suggest that RI might exaggerate muscle sympathetic nerve activity in patients with heart failure.