Transcatheter closure of large and complex atrial septal defect can pose challenges and complications during device placement. To improve stability, several assistive techniques have been developed.

This retrospective study evaluated the efficacy of the device-assisted device closure technique for large secundum atrial septal defects. Patients who underwent device-assisted device closure of atrial septal defect between December 2023 and August 2024 were analysed.

Twenty patients (mean age 38.69 years) underwent device closure of large secundum atrial septal defect with device-assisted device closure technique. The mean atrial septal defect diameter was 31.9 mm. The average thick-to-thick measurement was 38.3 mm, which determined the device size. The majority (18 cases) had thin, floppy margins and two had deficient inferior rim. Successful closure was achieved in 18 patients (90%), while two patients (10%) required other methods of assistance. Based on fluoroscopic guidance, patients were divided into two groups: Group A (8 patients) used anteroposterior projection, and Group B (12 patients) used left anterior oblique-cranial view. After initial two failures with anteroposterior view, all cases were successfully closed using left anterior oblique-cranial projection. Device sizes ranged from 36 to 50 mm (median 40 mm). Cocoon devices were used for sizes up to 42 mm, and Occlunix for larger devices. No significant procedural complications occurred, although two patients had minor post-procedural events.

Device-assisted device closure technique offers a promising and safe dynamic assistance approach for transcatheter closure of large and challenging atrial septal defects. The left anterior oblique-cranial view showed promising results, though without statistical significance. While results are encouraging, larger prospective studies are needed to validate its effectiveness.