C16 - Development of a Second-generation Vascular Occluder for Patent Ductus Arteriosus Occlusion in Dogs

Abstract: Background – We previously described a new canine patent ductus arteriosus (PDA) occlusion system in 2021. Dogs treated with the first-generation device were monitored for residual flow over three years. Residual flow persisted in about 30% of cases. Subsequently, a second-generation device was developed to address the issue of residual flow, based on a morphologic study of PDAs using CT. The device can be secured at the pulmonary ostium and is available with various waist diameter sizes. Hypothesis/Objectives – To describe the use of a second-generation occluder to close PDA. Animals – Thirteen dogs with PDA from July 2024 to December 2024. Methods – We retrospectively evaluated echocardiographic recordings in 13 dogs that underwent PDA occlusion using the second-generation vascular occlude at 1- and 30-days post-occlusion. Occluder size and residual flow were recorded. Occluder was chosen by the sizes of pulmonary ostium and ampulla. Results – Mean body weight was 3.70 kg (2.28–7 kg). All dogs had a PDA classified as type 2a, with a mean pulmonary ostium size of 2.7 mm (1.8–3.82 mm) by echocardiography. Occluder sizes used included 6 mm (n=2), 7 mm (n=2), 8 mm (n=5), 9 mm (n=3), and 10 mm (n=1). Complete occlusion of the PDA was achieved, with no residual flow detected at both 1 day and 1-month post-procedure in all 13 dogs. Conclusions and clinical importance – This second-generation PDA occluder appear to result in more complete ductal occlusion without residual flow when compared to the first-generation occluder. Figure 1: Second-generation vascular occluder