Background: There is a lack of feasible transcatheter occluder devices for the treatment of patent ductus arteriosus (PDA) in small dogs or those with ductal morphology not amenable to traditional devices. The Medtronic Microvascular Plug (MVP) is an ovoid-shaped, self-expanding device without retention discs that is safe and effective for transcatheter PDA closure in infants < 2.5kg. Hypothesis/
Objectives: To describe the novel use of the Medtronic MVP for transcatheter closure of left-to-right shunting PDA in dogs. Animals: Five client-owned dogs with left-to-right shunting PDAs that underwent ductal occlusion with a MVP between June 2024 and December 2025.
Methods: Case series. Five dogs underwent transarterial (n=1) or transvenous (n=4) PDA occlusion using the MVP. Occluder size was selected based on ampullar width. Echocardiography was repeated 1 day post-procedure.
Results: Median body weight was 2.9kg (1.3-5.1kg). Miller classification PDA morphology included types I (n=1) and IIa (n=4). Median ampullar width was 5.9mm (2.0-8.5mm). Median ratio of unconstrained device outer diameter to ampullar width was 1.6 (1.2-2.7). MVP sizes used were 3Q (5.3x12mm, n=1), 5Q (6.5x12mm, n=1), 7Q (9.2x16mm, n=1), and 9Q (13x18mm, n=2). Complete PDA occlusion was achieved in 2/5 patients, while residual flow was present in 3/5 patients 1-day post-procedure. No adverse events occurred. Conclusions and Clinical Importance: The Medtronic MVP appears safe and feasible for PDA occlusion in dogs with vessels too small for traditional devices. Shunting flow was substantially reduced in all dogs, with trace to moderate residual flow observed in 3/5 dogs.
