title: New coaxial transseptal needle for creation of atrial septal defects in adult sheep.
abstract: OBJECTIVE
  To introduce a new transseptal (TS) needle assembled in our laboratory--the coaxial TS (CTS) needle--and describe our experience with it in creating experimental atrial septal defects (ASD) in adult sheep.
  
  
  BACKGROUND
  With commercially available TS needles, we were not able to consistently perform TS puncture at the fossa ovalis in adult sheep.
  
  
  METHODS
  Ten adult sheep with a mean weight of 63.5 kg were used. The CTS needle consists of four components: a 9F Teflon catheter, a 14-gauge blunt curved-tip metal cannula, a 4F tapered catheter, and a 20-gauge open needle. A transjugular 5F pigtail catheter was used to display the septal anatomy by angiocardiography and was left in place to mark the level of the fossa ovalis. The septum was then probed by a transfemoral 5F curved-tip end-hole catheter. The CTS needle was aligned with the tip of the transjugular catheter, and the TS puncture was performed under fluoroscopic guidance. After documenting a left atrial position, a balloon angioplasty catheter was used for creation of the ASD.
  
  
  RESULTS
  A small patent foramen ovale was discovered by septal probing in one sheep. All sheep underwent successful TS punctures without complications. The ASD size ranged from 13 to 15 mm. In eight sheep, the ASD was in fossa ovalis. In the first two sheep where the needle was not well aligned with the marking catheter, the ASD was in the septum secundum. No damage to the atrial or other heart structures was found at necropsy.
  
  
  CONCLUSIONS
  The CTS needle is a suitable needle for TS puncture and ASD creation in adult sheep. Proper alignment of the CTS needle with a catheter marking the fossa ovalis is essential for successful puncture.
authors.affiliation: Dotter Interventional Institute, Oregon Health and Science University, L342, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.
authors.forename: Barry T
authors.initials: BT
authors.lastname: Uchida
authors.forename: Dusan
authors.initials: D
authors.lastname: Pavcnik
authors.forename: Masashi
authors.initials: M
authors.lastname: Shimohira
authors.forename: Young Ho
authors.initials: YH
authors.lastname: Choi
authors.forename: Miran
authors.initials: M
authors.lastname: Jeromel
authors.forename: Frederick S
authors.initials: FS
authors.lastname: Keller
authors.forename: Josef
authors.initials: J
authors.lastname: Rösch
mesh_terms: D015901:Angiography, Digital Subtraction; D000818:Animals; D006348:Cardiac Surgical Procedures / Q000295:instrumentation*; D017023:Coronary Angiography; D004195:Disease Models, Animal; D004867:Equipment Design; D006344:Heart Septal Defects, Atrial / Q000601:surgery*; D009339:Needles; D011677:Punctures; D015641:Radiography, Interventional; D012756:Sheep