ENDOCARDITIS RISK OF THE USCI PDA UMBRELLA FOR TRANSCATHETER CLOSURE OF PATENT DUCTUS-ARTERIOSUS

Background The USCI PDA Umbrella is a device to close patent ductus ar teriosus (PDA) by a transcatheter technique. Human clinical trials hav e shown excellent efficacy in reducing or eliminating the PDA shunt, b ut concerns remain about the risk of infection with this device. The p urpose of this study was to evaluate the risk of infection using an an imal model. Methods and Results Susceptibility to developing endocardi tis was tested by injecting a single intravenous dose of group L strep tococcus. Ten piglets with a closed ductus served as controls. Two of these developed valvular vegetations. PDA was produced in 19 animals b y balloon dilation of the ductus. Seven of 7 animals with PDA at the t ime of bacterial injection developed endarteritis of the ductus and va lvular vegetations. A PDA Umbrella was placed in the remaining 12 anim als, and bacteria were injected 2 weeks after device implantation. Inf ection was evident in the PDA Umbrella only in the single animal in wh ich the Umbrella had embolized and been left in the left pulmonary art ery. Three of the remaining 11 piglets had a significant residual leak , and all developed infection in the ductus and an additional valve. S imilar to the control group, none of the animals with complete (n=8) o r nearly complete (n=2) closure of the ductus by the PDA Umbrella had infection in or around the ductus, and only 1 had a valvular vegetatio n. Conclusions In this animal model, presence of a significant PDA shu nt (with or without a PDA Umbrella present) results in significantly i ncreased susceptibility to endarteritis and endocarditis. The PDA Umbr ella device does not appear to be susceptible to direct infection as e arly as 2 weeks after implantation if it is properly located in the du ctus arteriosus. Animals with no shunt or a trivial shunt are no more susceptible to developing endocarditis 2 weeks after PDA Umbrella impl antation than are controls.