ObjectiveTo explore the feasibility and effectiveness of transjugular patent ductus arteriosus (PDA) occlusion in dogs weighing <3 kg with a device called Nit-Occlud® PDA. HypothesisThe Nit-Occlud® method is a feasible and effective method for PDA closure in dogs weighing <3 kg. Animals, materials and methodsThis was a retrospective study. Clinical records of dogs that underwent PDA occlusion with a Nit-Occlud® PDA were reviewed. Data collection included patients' signalment, clinical findings, pre- and post-procedure echocardiographic measurements, device size, procedure time and clinical outcome. ResultsThirteen dogs that satisfied the inclusion criteria were reviewed retrospectively. The median age of these patients was six months (range: 2.5–38.0 months), with a mean body weight of 2.44 ± 0.43 kg. The mean minimal ductal diameter (MDD) was 1.82 ± 0.43 mm, while the mean ampulla diameter (AD) was 5.51 ± 1.89 mm. The Nit-Occlud® device size was selected following echocardiographic measurements of MDD and AD. Duct closure was successful in 12 cases, with a median procedure time of 62.5 min (range: 20.0–100.0 min). Minimal or no residual shunt was observed on echocardiography in these cases prior to device release. In one dog, the device was not released owing to unsatisfactory occlusion, prompting an alternative occlusion method. Follow-up echocardiographic examinations showed complete ductal closure and reversed cardiac remodelling in all cases where the device was successfully released. ConclusionThe Nit-Occlud® PDA coil appears feasible and effective in small patients weighing <3 kg.