Advancements in Transcatheter Interventions for Cyanotic Patients with Duct-Dependent and MBT Shunt-Dependent Pulmonary Circulation

This retrospective single-center study evaluates transcatheter cardiac interventions used to palliate cyanosis in neonates and young infants with cyanotic congenital heart disease (CCHD) and duct- or modified Blalock–Taussig shunt (MBTS)–dependent pulmonary circulation. A total of 177 neonates and infants younger than six months underwent ductal stenting (DS), MBTS creation, or transcatheter intervention for stenosed or obstructed MBTS at a university hospital in Bonn. Outcomes included procedural success, complications, mortality, need for reintervention, and short- to mid-term follow-up. <br> Special emphasis was placed on ductal morphology using a quantitative ductal curvature index (DCI). Patients with a DCI ≥0.45 demonstrated significantly higher complication rates, early stent failure, and unplanned interventions, identifying this group as high risk for ductal stenting. In contrast, patients with lower DCI values showed favorable outcomes. This study proposes, for the first time, a quantitative cutoff (DCI ≥0.45) to stratify procedural risk in ductal stenting. <br> Overall comparison between DS and MBTS revealed similar primary success rates; however, hospital mortality and need for extracorporeal membrane oxygenation were significantly higher following MBTS. In high-risk patients with severe ductal tortuosity, MBTS achieved higher procedural success but was associated with increased mortality. Conversely, DS proved superior in patients with pulmonary atresia with intact ventricular septum and right ventricular–dependent coronary circulation, reducing ischemic complications and ventricular arrhythmias. <br> Transcatheter treatment of stenosed or obstructed MBTS was shown to be safe and effective, including in high-risk populations such as hypoplastic left heart syndrome. Thrombotic complications remained a major challenge, particularly in patients requiring multiple stents or ECMO support, underscoring the importance of thrombophilia screening and dual antiplatelet therapy. <br> Transcatheter interventions represent a safe and life-saving palliative strategy when tailored to ductal anatomy and patient-specific risk profiles.