Despite being widely reported in patients with neoplasms, vena cava superior (VCS) syndrome linked to thrombosis is a major catheter complication that can be encountered during the use of the hemodialysis catheter. Antithrombin III (AT-III), responsible for a large part of thrombin inactivation capacity in plasma, is the most powerful inhibitor of the thrombosis process. This report describes a case of VCS syndrome developing two weeks following the extraction of a right-sided subclavian catheter in a patient transferred from peritoneal dialysis to hemodialysis for one week due to leakage. The patient presented complaining of swelling and pain in the right arm. At Doppler examination, total thrombosis was observed in the subclavian and internal jugular vein. At advanced examinations due to lack of response to heparin and clinical worsening, VCS and AT-III deficiency were determined. Following thrombolytic therapy with streptokinase, AT-III levels were raised by the administration of plasma, and clinical and radiological stabilization was established by continuing heparin and continuous oral anticoagulant therapy.