Pacemaker-induced SVC syndrome. The superior vena cava (SVC) syndrome is an uncommon but sometimes serious complication associated with permanently implanted pacemakers. The mechanical stress associated with pacemaker wires may lead to vessel wall inflammation, fibrosis, thrombus formation, and, ultimately, venous stenosis and occlusion. The surgical treatment of pacemaker-related SVC syndrome requires thoracotomy and may result in significant morbidity. The long-term effects on the pacemaker electrodes, due to compression between the stent and the wall of the vein, remain unknown. We describe a case in which balloon venoplasty successfully resolved the SVC syndrome. The patient has remained symptom-free and with normal pacemaker function for 6 months.