Objective: Document safety and efficacy of transvenous catheter occlusion of patent ductus arteriosus (PDA) over a wide range of ductal and patient sizes. Animals, materials and methods: Retrospective study of fifty-six consecutive dogs referred to Colorado State University with diagnosis of PDA. All cases utilized the transvenous approach, via the femoral vein. Occlusion was achieved using a coil (FlipperΓ€) in dogs with PDA minimal dimension of 4 mm. Amplatzer Γ duct occluder or Amplatzer Γ vascular plugs were used in dogs with PDA minimal dimension >4 mm, or if a coil was unstable following deployment. Results: Ductal occlusion was achieved using the transvenous route alone in 54/56 dogs (96.4%). Occlusion was achieved using detachable FlipperΓ€ coils in 39/42 dogs (92.9%) in which coil occlusion was attempted, with 38/39 dogs (97.4%) requiring only a single coil. In 16 dogs, occlusion was achieved using an Amplatzer Γ duct occluder or vascular plug. Post-procedure residual ductal flow was absent or only mild in 36/39 (92.3%) dogs in which it was assessed. Procedural mortality rate was 1.7%, and major complication rate 7.0%. Conclusion: Transcatheter occlusion via a transvenous approach is a safe and effective method for treating PDA in dogs and is useful for small dogs (<2.5 kg).