title: Usefulness of the right parasternal approach to evaluate the morphology of atrial septal defect for transcatheter closure using two-dimensional and three-dimensional transthoracic echocardiography.
abstract: BACKGROUND
  The aim of this study was to demonstrate the feasibility and usefulness of addition of the right parasternal approach to the conventional left parasternal and apical approaches using two-dimensional (2D) and three-dimensional (3D) transthoracic echocardiography (TTE) for morphologic evaluation in cases of transcatheter closure of atrial septal defects (ASDs).
  
  
  METHODS
  In 112 consecutive patients with ASDs, the morphology of the defects was evaluated for transcatheter closure in the right parasternal view in addition to the conventional left views using 2D and 3D TTE. Measurements of the maximal ASD diameter and detection of deficient rim obtained on 2D TTE were compared with those obtained by 2D transesophageal echocardiography. The shapes and locations of ASDs visualized by 3D TTE were compared with those visualized by 3D transesophageal echocardiography.
  
  
  RESULTS
  In 88 patients (80.0%), optimal images from the right parasternal approach for morphologic evaluation of ASDs were obtained. Although there was a significant difference in maximal ASD diameter obtained only in the conventional left approach compared with transesophageal echocardiographic measurements (P < .05), when the right parasternal approach was applied, a significant difference was not found (P = .18), and the diagnostic concordance of the rim deficiency was improved from 85.2% to 90.9%. Three-dimensional TTE from the right parasternal approach improved visualization of the shape and location of ASDs from 65.5% to 74.5%.
  
  
  CONCLUSIONS
  Additional use of the right parasternal approach enables detailed morphologic evaluation for transcatheter closure of ASDs. In patients with suboptimal images on 3D TTE in the left conventional approach, additional 3D TTE in the right parasternal approach can improve the feasibility of obtaining optimal 3D images to evaluate the shapes and locations of ASDs.
authors.affiliation: Division of Medical Support, Okayama University Hospital, 2-5-1 Kita-ku Shikata-Cho, Okayama, Japan.
authors.forename: Nobuhisa
authors.initials: N
authors.lastname: Watanabe
authors.forename: Manabu
authors.initials: M
authors.lastname: Taniguchi
authors.forename: Teiji
authors.initials: T
authors.lastname: Akagi
authors.forename: Yasuharu
authors.initials: Y
authors.lastname: Tanabe
authors.forename: Norihisa
authors.initials: N
authors.lastname: Toh
authors.forename: Kengo
authors.initials: K
authors.lastname: Kusano
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ito
authors.forename: Norio
authors.initials: N
authors.lastname: Koide
authors.forename: Shunji
authors.initials: S
authors.lastname: Sano
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D004452:Echocardiography / Q000379:methods*; D019560:Echocardiography, Three-Dimensional; D017548:Echocardiography, Transesophageal; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019919:Prosthesis Implantation / Q000379:methods*; D055989:Septal Occluder Device; D055815:Young Adult