The HLM is turned off and the aortic and atrial cannula are removed, then an incision is made in the right atrium, through which the congenital or palliative atrial septal defect (ASD) is repaired; where a Rashkind balloon atrial septostomy was used, the ASD should be able to be closed with sutures, but cases involving large congenital ASDs or Blalock-Hanlon atrial septectomy, a pericardial, xenograft, or Dacron patch may be necessary. If there is a VSD which has not yet been repaired, this is performed via the atrial incision and tricuspid valve, using sutures for a small defect or a patch for a large defect.
