Transseptal Puncture in Children Weighing Less Than 20 kg in Invasive Cardiac Catheterization and Electrophysiology

Introduction: Transseptal puncture (TSP) is a widely utilized technique for left-sided electrophysiological studies (EPS), interventions in left heart lesions, or creating interatrial shunts in congenital heart diseases (CHD). This study aims to evaluate the outcome of TSP in children under 20 kg. Methods: This retrospective study analyzed TSP procedures in infants and children <20 kg between December 2015 and December 2021. TSPs were performed with a biplane angiography system in the catheter angiography laboratory. A Brockenbrough needle (BRK Transseptal Needle; Abbott/St.Jude Medical, Inc) was used for TSP. In patients whose Brockenbrough needles could not achieve sufficient patency, TSP was performed by applying cautery energy over the Brockenbrough needle. Results: Twenty-one patients were studied (8 females, median age 2.6 years, median weight 12 kg), and 66% required TSP for CHD, including HLHS and pulmonary hypertension. The CHD group had younger patients (median age: 6.6 months) with smaller weights (median: 5.7 kg) compared to the catheter ablation group. TSP success rate was lower in patients with CHD, especially those with complex anatomy. Radiofrequency energy was used without complications in three cases when traditional methods failed. In four patients, the septum couldn't be traversed. The median weight of the patients who failed TSP was 3,4 kg. The only major complication was pericardial tamponade developed in two patients diagnosed with hypoplastic left heart syndrome. Conclusion: TSP is a safe option when carefully selected but carries higher risks in complex CHD with abnormal cardiac anatomy compared to patients with normal anatomy used for electrophysiology procedures.