BACKGROUND : Substantial technical challenges exist in placing transvenous pacing leads in the heterogeneous adult congenital heart disease patient population. Anatomical issues including occlusion of central veins, single ventricle physiology, and lack of transvenous access to systemic right ventricles, often require thoracotomy for epicardial lead placement. METHODS : We assessed the feasibility of performing a totally thoracoscopic approach to epicardial pacing lead implantation in 10 adult patients (mean age 32.5 years) with congenital heart disease. The underlying cardiac anatomy consisted of transposition of the great arteries, status post (s/p) Mustard procedure (3); tricuspid atresia, s/p Fontan procedure (3); congenitally corrected transposition (1); Ebstein's anomaly, s/p tricuspid valve replacement (1); AV canal, s/p repair (1); and hypertrophic cardiomyopathy, s/p myomectomy (1). Twenty-six previous cardiac operations (mean 2.8 per patient) had been performed in this group. RESULTS : Indications for thoracoscopic lead insertion included primary rhythm disturbances, progressive heart failure with a QRS>120 milliseconds, and an unapproachable coronary sinus or failed transvenous lead insertion. All patients underwent thoracoscopic implantation of 2 epicardial leads to the systemic ventricle and generator insertion. Intraoperative transesophageal echocardiography (TEE) was used in all cases, which facilitated port placement. Measurements at operation showed mean threshold of 2.0V (95% CI 0.9-3.1V at 0.5 milliseconds) and a mean impedance of 1259 Ohms (95% CI 418-2100). There were no procedural related complications and no patient required conversion to an open procedure. Seventy percent of patients were extubated immediately after the procedure and were discharged from the intensive care unit within 24 hours. There was 1 noncardiac death due to gastrointestinal ischemia. CONCLUSION : Adults with congenital heart disease present significant challenges to pacing lead implantation including variability of the location of the systemic ventricle, coronary sinus anatomy, right-sided valve replacement, a small thoracic cavity, limited vascular access, and adhesions from prior cardiac procedures. Additionally, thoracoscopy has been previously considered a contraindication in this subgroup of patients. However, we have demonstrated that with careful preoperative planning and the assistance of TEE, a totally thoracoscopic approach to epicardial lead implantation is both feasible and safe.