title: Excision of the coronary orifices in arterial switch operation: "O" like obstructive and "U" like unobstructive?
abstract: BACKGROUND
  Stenoses of the neo-pulmonary artery (NPA) may complicate follow-up of the arterial switch operation (ASO). It is unknown whether the type of patch covering the coronary excision defects ("O"- or "U"-shaped) might influence this complication.
  
  
  METHODS
  Echocardiographically and invasively measured NPA pressure-gradients were evaluated retrospectively in 95 children after ASO. Median follow-up was 5.8 years. Defects had been covered with pericardial patches: O/O and U/U (left/right) 34 x each, and 27 x in mixed combinations. The frequency of NPA stenoses requiring re-interventions was registered.
  
  
  RESULTS
  Median of the peak instantaneous echocardiographic pressure gradient was 23 mmHg (interquartile range, IQR: 16 - 49, n = 34) in O/O, and 19 mmHg (IQR: 13 - 23, n = 34) in U/U; p < 0.034, t-test. Invasively measured gradients were 49 mmHg (IQR: 17 - 65, n = 12) in O/O, and 12 mmHg (IQR: 7-21, n = 28) in U/U; p < 0.001. One child per O/O- and U/U-group underwent balloon angioplasty of the neo-pulmonary root. Five children of the O/O-group had to undergo repeat surgery, whereas only one child in the U/U-group required repeat surgery ( p < 0.34).
  
  
  CONCLUSIONS
  The preferential type of covering the NPA coronary excision sites in ASO should be U-shaped.
authors.affiliation: Department of Thoracic, Cardiac and Vascular Surgery, Tübingen University Hospital, Tübingen, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Beierlein
authors.forename: H-P
authors.initials: HP
authors.lastname: Freitag
authors.forename: S
authors.initials: S
authors.lastname: Salehi-Gilani
authors.forename: R
authors.initials: R
authors.lastname: Kaulitz
authors.forename: B
authors.initials: B
authors.lastname: Pietsch
authors.forename: I
authors.initials: I
authors.lastname: Luhmer
authors.forename: M
authors.initials: M
authors.lastname: Hofbeck
authors.forename: G
authors.initials: G
authors.lastname: Ziemer
mesh_terms: D000714:Anastomosis, Surgical; D015906:Angioplasty, Balloon, Coronary; D006348:Cardiac Surgical Procedures; D003251:Constriction, Pathologic; D005260:Female; D006801:Humans; D008297:Male; D019736:Prostheses and Implants; D011651:Pulmonary Artery / Q000473:pathology; D012086:Reoperation; D012189:Retrospective Studies; D014188:Transposition of Great Vessels / Q000601:surgery*