Immediate Echocardiographic Surveillance After Transcatheter Closure of a Patent Ductus Arteriosus: A Feasible Method to Assess Residual Shunt

BackgroundTo evaluate the feasibility of echocardiography after transcatheter closure of patent ductus arteriosus (PDA) with coils.MethodsBetween April 1998 and December 2006, 131 patients had transcatheter coil occlusion of their PDA using Gianturco coils. We hypothesized that post-procedural hemolysis would not occur if a residual shunt < 1 mm or if no continuous waveform was detected by echocardiography. Immediately after coil implantation, patients without and with a residual shunt as detected by echocardiography were designated to groups A and B, respectively. The clinical presentations, laboratory data and outcomes were compared between the two groups.ResultsThere were 101 patients in group A and 30 patients in group B. Patients in group B had larger ductal diameter (2.8 ± 0.9 mm vs. 1.6 ± 0.8 mm; p < 0.001), larger Qp/Qs (1.9 ± 0.9 vs. 1.3 ± 0.4; p = 0.001), higher frequency of more than one coil used (14/30 vs. 11/101; p < 0.001), and female predominance (22/30 vs. 53/101; p = 0.043) compared with group A. Trivial residual shunt was noted in 6 patients in group A and 20 patients in group B on the day after embolization. All shunts spontaneously closed within 6 months in patients of group A, while five patients in group B had a persistent shunt at the 1-year follow-up and thereafter. Although the patients in group B had higher residual shunt rate than group A during follow-up (p < 0.001), none of these patients suffered from hemolysis.ConclusionEchocardiography is a feasible tool to assess residual shunt after PDA closure. If a residual shunt < 1 mm or if no continuous waveform is detected by echocardiography, the risk of developing hemolysis is low.