Transcatheter Ventricular Septal Defect Closure in Children < 10 kg: Anatomical Challenges, and Outcomes with the Konar MFO Device.

This study evaluated the feasibility, safety, and mid-term outcomes of transcatheter ventricular septal defect (VSD) closure using the Konar MFO device in infants weighing < 10 kg, focusing on procedural challenges and anatomical complexities. A retrospective single-center analysis included 34 consecutive patients (mean age: 14.8 months; mean weight: 7.4 kg) who underwent transcatheter VSD closure between January 2022 and December 2024 via transfemoral or transjugular approaches. Technical success was achieved in 94.1% (32/34) of cases. Major complications were rare (5.9%), with no device embolization, arrhythmias, or new-onset valvular regurgitation. The Konar MFO device was successfully deployed across diverse VSD morphologies, including perimembranous, muscular outlet, mid-muscular, and apical-muscular defects, as well as cases with aortic override or multifocal defects requiring dual-device implantation. Procedural challenges, such as papillary muscle knotting during wire manipulation, were managed with tailored strategies, enabling safe device placement in all patients. Individualized procedural modifications, including novel dual-device and access strategies, enabled safe closure even in anatomically complex cases. At a median follow-up of 17 months, all patients demonstrated sustained defect closure, hemodynamic improvement, and resolution of symptoms. In conclusion, transcatheter VSD closure with the Konar MFO device provides high procedural success and favorable mid-term outcomes in infants < 10 kg, including those with challenging anatomies. Unlike previous reports focusing mainly on procedural success, this study systematically addresses anatomical complexities and mid-term outcomes in infants < 10 kg. Larger multicenter studies with extended follow-up are needed to confirm long-term safety and standardize procedural strategies.