title: Catheter closure of patent ductus arteriosus in dogs: variation in ductal size requires different techniques.
abstract: BACKGROUND
  : Catheter closure of patent ductus arteriosus Botalli (PDA) is increasingly replacing traditional surgical ligation via thoracotomy. A variety of techniques have been described in dogs, although the technique and implant chosen may depend on the minimum ductus diameter.
  
  
  OBJECTIVE
  : To evaluate the feasibility and treatment of choice of catheter closure of large and small PDAs in dogs.
  
  
  METHODS
  : In 16 dogs with a PDA, catheter closure was performed using transarterial embolisation using detachable or free coils, or transvenously using an Amplatzer, duct occluder (ADO).
  
  
  RESULTS
  : In 8 dogs, closure of PDA with a minimum diameter of < 4 mm was achieved using detachable coils; 2 or more coils were required in 3 dogs. In 5 dogs with minimum ductus diameters of > 4 mm, detachable coils were not applicable. In one of these dogs, (incomplete) surgical ligation was performed and later a free coil placed for complete closure. In 2 dogs with moderately large PDA (5 mm), several free coils were implanted. Complete closure was not achieved in either dog and transient haemolysis occurred as a complication. In 2 dogs with a very large PDA (6 mm), implanted free coils embolised to pulmonary arteries and closure was then achieved using an ADO. In 3 dogs with an excessively large PDA (7.5-10 mm) closure was successfully achieved using an ADO with no complications.
  
  
  CONCLUSIONS
  : Coil embolisation is readily feasible for closure of PDA < 4 mm, less feasible for PDA < 5 mm and unlikely to be feasible to close PDA > 5 mm. Detachable coils are safe for PDA < 4 mm, and the ADO is an excellent device for PDA > 5 mm.
authors.affiliation: Divisions of Cardiology, Department of Small Animals, Leicester, United Kingdom.
authors.forename: Tony M
authors.initials: TM
authors.lastname: Glaus
authors.forename: Mike
authors.initials: M
authors.lastname: Martin
authors.forename: Manuel
authors.initials: M
authors.lastname: Boller
authors.forename: Mike
authors.initials: M
authors.lastname: Stafford Johnson
authors.forename: Annette
authors.initials: A
authors.lastname: Kutter
authors.forename: Mark
authors.initials: M
authors.lastname: Flückiger
authors.forename: Magdi
authors.initials: M
authors.lastname: Tofeig