title: Right-Dominant Unbalanced Atrioventricular Septal Defect: Echocardiography in Surgical Decision Making.
abstract: BACKGROUND
  Management of right-dominant atrioventricular septal defect (AVSD) remains a challenge given the spectrum of ventricular hypoplasia. The purpose of this study was to assess whether reported echocardiographic indices and additional measurements were associated with operative strategy in right-dominant AVSD.
  
  
  METHODS
  A blinded observer retrospectively reviewed preoperative echocardiograms of patients who underwent surgery for right-dominant AVSD (January 2000 to July 2013). Ventricular dimensions, atrioventricular valve index (AVVI; left valve area/right valve area), and right ventricular (RV)/left ventricular (RV/LV) inflow angle were measured. A second observer measured a subset of studies to assess agreement. Pearson correlation analysis was performed to examine the relationship between ventricular septal defect size (indexed to body surface area) and RV/LV inflow angle in systole. A separate validation cohort was identified using the same methodology (August 2013 to July 2016).
  
  
  RESULTS
  Of 46 patients with right-dominant AVSD (median age, 1 day; range, 0-11 months), overall survival was 76% at 7 years. Twenty-eight patients (61%) underwent single-ventricle palliation and had smaller LV dimensions and volumes, AVVIs (P = .005), and RV/LV inflow angles in systole (P = .007) compared with those who underwent biventricular operations. Three patients undergoing biventricular operations underwent transplantation or died and had lower indexed LV end-diastolic volumes compared with the remaining patients (P = .005). Interobserver agreement for the measured echocardiographic indices was good (intraclass correlation coefficient = 0.70-0.95). Ventricular septal defect size and RV/LV inflow angle in systole had a strong negative correlation (r = -0.7, P < .001). In the validation cohort (n = 12), RV/LV inflow angle in systole ≤ 114° yielded sensitivity of 100% and AVVI ≤ 0.70 yielded sensitivity of 88% for single-ventricle palliation.
  
  
  CONCLUSIONS
  Mortality remains high among patients with right-dominant AVSD. RV/LV inflow angle in systole and AVVI are reproducible measurements that may be used in conjunction with several echocardiographic parameters to support suitability for a biventricular operation in right-dominant AVSD.
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Stanford University Medical Center, Palo Alto, California. Electronic address: alisa.arunamata@stanford.edu.
authors.forename: Alisa
authors.initials: A
authors.lastname: Arunamata
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Stanford University Medical Center, Palo Alto, California.
authors.forename: Sowmya
authors.initials: S
authors.lastname: Balasubramanian
authors.affiliation: Department of Cardiovascular Surgery, Stanford University Medical Center, Palo Alto, California.
authors.forename: Richard
authors.initials: R
authors.lastname: Mainwaring
authors.affiliation: Department of Cardiovascular Surgery, Stanford University Medical Center, Palo Alto, California.
authors.forename: Katsuhide
authors.initials: K
authors.lastname: Maeda
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Stanford University Medical Center, Palo Alto, California.
authors.forename: Elif Seda
authors.initials: ES
authors.lastname: Selamet Tierney
mesh_terms: D006332:Cardiomegaly / Q000000981:diagnostic imaging* / Q000401:mortality / Q000601:surgery*; D000066491:Clinical Decision-Making / Q000379:methods; D004452:Echocardiography / Q000379:methods / Q000706:statistics & numerical data*; D005260:Female; D006343:Heart Septal Defects / Q000000981:diagnostic imaging* / Q000401:mortality / Q000601:surgery*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D015588:Observer Variation; D011300:Preoperative Care / Q000706:statistics & numerical data*; D015995:Prevalence; D011379:Prognosis; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D015996:Survival Rate; D016896:Treatment Outcome
keywords: Biventricular operation; Echocardiography; Unbalanced atrioventricular septal defect