A BALLOON COIL DEVICE FOR PDA OCCLUSION: PRELIMINARY IN VIVO RESULTS

Abstract

Transcatheterism devices for the closure of Patent Ductus Arteriosus (PDA) with diameters larger than 4mm present limitations. The objective of this study was to improve the design of a balloon-coil device (BCD) for the closure of PDAs with diameters greater than 4mm, and to evaluate its safety and efficiency in an animal model. Methods The BCD consists of a detachable balloon catheter with a coil overhanging on both sides. The balloon is inflated to avoid blood flow through the axis of the PDA and the coil gives support to the device and promotes thrombus formation. Design and manufacture of the BCD were improved by producing an implant that fits different PDA diameters. BCD can be implanted by standard transcatheterism techniques. The BCD was evaluated in a PDA model with newborn calves (n=6). Device implantation consisted of: placement of the BCD in the PDA, balloon inflation, coil release on both sides of the balloon and BCD detachment. Results The BCD was successfully implanted in 2 animals. Angiographical and pathological evaluation were done 21 days after BCD implantation to check the complete occlusion of the PDA. Both devices were inflated and surrounded by initial thrombus inside the DAP. Microscopical evaluation showed early phase thrombus, elastic internal membrane injuries and calcifications, which are indicative of the initiation of permanent PDA closure. Further studies are directed to improve device fabrication and implantation efficacy.