Introduction: Controlled energy delivery through a catheter has been demonstrated in clinical practice since 1991, primarily for pulmonary valvuloplasty (PV). Since then, its use has expanded to different percutaneous procedures (PP). In underdeveloped countries, the use of the electrosurgical unit (ESU) as an alternative has been described. Objective: To analyze the use of ESU in PP in children with congenital heart disease (CHD), emphasizing technical aspects and clinical outcomes. Method: A retrospective analysis of patients under 18 years old with CHD from a quaternary hospital database was conducted. Success was defined as planned perforation without injury to adjacent structures, pre-procedure risk was calculated by the CRISP score, and deaths within 48 hours were considered PP-related. All PPs were performed under general anesthesia and mechanical ventilation. A 0.014" guidewire connected to an electrosurgery device was used for perforation, with voltage at the interventionist's discretion. In specific cases, a microcatheter was used. Results: Twenty-seven children with a median age of 0.48 (0.0-15.6) years and weight of 6.0 (2.0-62.0) kilograms were included. PPs performed included atrial septostomy (40.7%) - with 54.5% of these in hypoplastic left heart syndrome - and PV (22.2%) - with 66.6% in pulmonary atresia with ventricular septal defect. Surgical shunt angioplasty accounted for 7.4% and other PPs for 29.6%. The median voltage used was 80 (20-80) Watts. Fifteen patients (55.5%) had a risk of severe adverse events, with three (11.1%) experiencing severe complications, all weighing less than 5 kg and age under 30 days old. The success rate was 88.9%, with two cases unable to puncture the pulmonary valve and one unable to puncture the obstructed pulmonary artery. There were no intra-procedural or procedure-related deaths. Conclusion: The ESU was used in children with CHD with a high success rate and lower-than-expected incidence of severe complications, considering clinical characteristics and procedural risks.