A SMALL INTERVENTIONAL DEVICE TO OCCLUDE PERSISTENTLY PATENT DUCTUS-ARTERIOSUS IN NEONATES - EVALUATION IN PIGLETS

Objectives. We attempted to evaluate the efficacy and tissue reaction of a new miniature interventional ductal occlusion device in neonatal pigs. Background. A variety of devices are used to close persistent du ctus arteriosus (PDA) by interventional measures. Because of the size of these devices, they have not been applied to term or preterm neonat es. Newborn piglets are comparable in size and fragility to human term and preterm neonates. Methods. Memory-shaped double-cone stainless st eel coils were mounted on a titanium-nickel core wire. A snap-in mecha nism attaches the coil to the delivery wire, allowing intravascular co il retrieval and repositioning. The system was placed through a 3F Tef lon catheter. Two piglet models of PDA were used: 1) ductal patency ma intained by stents (n = 6), and 2) ductal patency produced by angiopla sty (n = 7) to avoid stent-coil interaction. Results. Placement of the coils within the PDA was possible in all piglets. Before final detach ment, the coils were retrieved or repositioned, or both, up to eight t imes. In all but two piglets the ductus was closed within 1 h of the p rocedure. The coils were never dislocated and caused no infections or relevant aortic and pulmonary artery obstruction (95% confidence inter val for missing complications [0 of 13] extends to 23%). Histologic an d electron microscopic studies revealed endothelial coverage of the im plants and histiocytic reaction but no local or systemic inflammation or erosion of the implant. Conclusions. The device was effective in ex perimental models of PDA, The information obtained warrants initial tr ials of the device in neonates.