Superior vena cava syndrome is a rare, but nevertheless well known complication of permanent pacemaker implantation. Nowadays cardioverter defibrillators are also routinely implanted transvenously. A superior vena cava syndrome occurred in a 48-year-old female 2 years after implantation of cardioverter defibrillator. The clinical problem, in the presence of a predisposing thrombophilic condition (circulating lupus anticoagulant), resolved only partially after treatment with thrombolytics and oral anticoagulation. This syndrome should be recognized as a possible important complication of defibrillator therapy and requires lifelong anticoagulation.