title: Long-term predictors of aortic root dilation and aortic regurgitation after arterial switch operation.
abstract: BACKGROUND
  Neo-aortic root dilation (ARD) and neo-aortic regurgitation (AR) may be progressive after arterial switch operation (ASO) for d-loop transposition of the great arteries (dTGA). We sought to identify predictors of ARD and AR after ASO.
  
  
  RESULTS
  335 patients were identified who underwent ASO for dTGA with intact ventricular septum or ventricular septal defect (VSD), including double-outlet right ventricle (DORV), before 2001 with at least 1 postoperative echocardiogram at our institution, at least 1 year after ASO, and no previous atrial switch procedure (median follow-up of 5.0 years). Probability of freedom from ARD was 97%, 92%, 82%, and 51%, from at least moderate AR was 98%, 97%, 96%, and 93%, and from neo-aortic valve or root surgery was 100%, 100%, 99%, and 95%, at 1, 2, 5, and 10 years, respectively. For patients in whom ARD developed, progressive dilation was not observed during late follow-up. By Kaplan-Meier method, independent predictors of ARD, with neo-aortic root z-score of > or =3.0, were previous pulmonary artery band (PAB) (P=0.002, hazard ratio [HR]=2.4) and later time period when ASO was performed (P<0.002, HR=19.0). Risk factor for at least moderate AR was age > or =1 year at ASO (P=0.002, HR=5.8), which was closely related to VSD repair at ASO (P<0.001) and previous PAB.
  
  
  CONCLUSIONS
  Significant ARD and AR continue to develop over time after ASO, but ARD does not tend to be progressive during late follow-up. Previous PAB was a significant risk factor for ARD. Older age at time of ASO, presence of VSD, and previous PAB were risk factors for AR.
authors.affiliation: Department of Cardiology, Children's Hospital, 300 Longwood Avenue, Boston, Mass 02115, USA. Marcy.Schwartz@cardio.chboston.org
authors.forename: Marcy L
authors.initials: ML
authors.lastname: Schwartz
authors.forename: Kimberlee
authors.initials: K
authors.lastname: Gauvreau
authors.forename: Pedro
authors.initials: P
authors.lastname: del Nido
authors.forename: John E
authors.initials: JE
authors.lastname: Mayer
authors.forename: Steven D
authors.initials: SD
authors.lastname: Colan
mesh_terms: D000015:Abnormalities, Multiple / Q000601:surgery; D001017:Aortic Coarctation / Q000601:surgery; D001018:Aortic Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology*; D001022:Aortic Valve Insufficiency / Q000000981:diagnostic imaging / Q000453:epidemiology*; D015331:Cohort Studies; D004108:Dilatation, Pathologic / Q000000981:diagnostic imaging / Q000453:epidemiology; D018450:Disease Progression; D004310:Double Outlet Right Ventricle / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006345:Heart Septal Defects, Ventricular / Q000601:surgery; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D015993:Life Tables; D008297:Male; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000453:epidemiology*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D014188:Transposition of Great Vessels / Q000601:surgery*; D016896:Treatment Outcome; D014463:Ultrasonography