Transcatheter closure of the perimembranous ventricular septal defect - Preclinical trial of a new amplatzer device

Objectives: This study assessed the feasibility and efficacy of implanting a new nitinol device for closure of perimembranous ventricular septal defects in a swine model. Background: Perimembranous ventricular septal defect occurs in 80% of patients requiring treatment for congenital heart disease. Methods: The Amplatzer perimembranous ventricular septal occluder device (pmVSO2 device, AGA Medical Company, Plymouth MN) is a new transcatheter Nitinol device containing polyester fabric designed to close the perimembranous ventricular septal defect (VSD). The device has 75% reduction in radial force, 45% reduction in clamping force, and increased stability as compared to the previous version. The device was implanted in six swine with naturally occurring perimembranous VSD with immediate, 1, 7, ∼30, and ∼90 day followup by echocardiography, angiography, and final pathological examination. Results: The device was successfully implanted in all animals and was retrievable and repositionable. There was complete occlusion of the VSD in five of six cases without embolization. There was no thrombus formation on the device or occurrence of complete heart block. A single instance of a tiny residual shunt was attributed to capture of tricuspid valve apparatus. Conclusions: The success of this animal study confirms safety and feasibility of the Amplatzer pmVSO2 device. Human trials are planned.