title: A novel "in-situ tulip-bud deployment" method for transcatheter closure of secundum atrial septal defect.
abstract: OBJECTIVE
  We devised a new technique for interventional closure of atrial septal defect (ASD) using the Amplatzer Septal Occluder (ASO), and validated this by comparing it with a cohort using the conventional method.
  
  
  BACKGROUND
  Transcatheter closure of ASD is a widely accepted modality of treatment. Although the outcome is good, there are occasional technical difficulties encountered.
  
  
  METHODS
  In this three-step technique, the device is protruded to form a "tulip bud." This "tulip bud" is then aligned adjacent to and along the plane of the ASD. The second step involves withdrawing the sheath in quick succession to deploy atrial discs over the septal defect. Finally, good placement of the occluder is checked before release.
  
  
  RESULTS
  Twenty-seven consecutive patients (1.4-77.2 years of age, median = 15) underwent device closure by this method. Nineteen (70.4%) had a deficient aortic rim (< 5 mm). Mean (+/- SD) ASD size by transesophageal echocardiography (TEE) was 16.0 +/- 5.1 mm. The chosen ASO size was 122 +/- 8% of the ASD size. The mean (+/- SD) duration of deployment and of deployment to release was 1.27 +/- 1.91 minutes and 5.18 +/- 2.63 minutes, respectively. The total fluoroscopy and procedure time was 9.93 +/- 5.61 minutes and 68.67 +/- 28.39 minutes, respectively. Twenty-one out of 27 patients (77.8%) had closure in one attempt. Comparing these 27 patients with the previous 48 consecutive patients with a deficient aortic rim by the conventional method, there was no difference in age, body weight, Qp/Qs, ASD size and ASO size or degree of oversizing (p > 0.05). The percentage of patients with aortic root deficiency was slightly higher in "tulip-bud" group compared to the conventional group (63.2% vs. 58.4%; p = 0.039). No complications were observed in either series.
  
  
  CONCLUSIONS
  This is a promising new method to circumvent some of the difficulties associated with closure of large ASDs and deficient aortic rim.
authors: Department of Paediatrics, National University of Singapore, Singapore and the Gleneagles Hospital, Singapore. paeqsc@nus.edu.sg
authors: Swee Chye
authors: SC
authors: Quek
authors: Wen Xia
authors: WX
authors: Wu
authors: Kit Yee
authors: KY
authors: Chan
authors: Patrick
authors: P
authors: Ang
authors: Ting Fei
authors: TF
authors: Ho
authors: William
authors: W
authors: Yip
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D006328:Cardiac Catheterization / Q000379:methods; D013504:Cardiovascular Surgical Procedures / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D017548:Echocardiography, Transesophageal; D005260:Female; D005471:Fluoroscopy; D006344:Heart Septal Defects, Atrial / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D055989:Septal Occluder Device / Q000009:adverse effects; D016896:Treatment Outcome; D055815:Young Adult