AVP and Hyponatremia: Hyponatremia is usually caused by visceral and systemic vasodilation, which is the reduction of effective arterial blood volume, resulting in excessive impermeable secretion of antidiuretic hormone.29 A previous study30 published in 2005 showed that hyponatremia may increase the mortality of patients with liver cirrhosis by 7 folds within 3 months (3-month), which has aroused great concern.