Vasopressin antagonism: a future treatment option in heart failure.

Arginine vasopressin plays an important role in volume homeostasis. Patients with heart failure have chronically elevated plasma vasopressin concentrations which may contribute to their clinical syndrome of fluid retention. Recently, a number of agents have been developed to antagonize the effects of vasopressin by targeting its V1a and V2 receptors, which are involved in vascular tone and free water regulation, respectively. Two vasopressin antagonists, in particular, tolvaptan and conivaptan, have shown promise in animal studies and small-scale human trials. The following is a review of current experimental and clinical studies using vasopressin antagonists and their potential role in the treatment of heart failure.