Objective   To investigate the establishment of atrial septal defect model with high success rate in pigs with extracorporeal circulation and the method of followed patch repair.

  Methods  Twenty Chinese miniature pigs weighing 45.3-55.7 kg were used, four of which were used for blood donationand the remaining for models. General anesthesia was conducted with intubation. Thoracotomy was performed through the right fourth intercostal space, and the ascending aorta cannulation with a wire-guide technique was carried out. The extra-pericardial method was used for the superior and inferior vena cava cannulation. The ascending aorta was not cross-clamped. After snaring the superior and inferior vena cava, the right atrium was opened on pump. Sutures were preset and a clamp was used to create and expand an interatrial septal hole followed by the implantation of the experimental patch.

  Results  One animal died due to the aortic root torn and hemorrhage while exposing the right atrial appendage. The remaining 15 pigs successfully completed the operation. Among these 15 experimental animals, one had postoperative hypotension. The average pressure was decreased to 38 mmHg (1 mmHg=0.133 kPa), which was corrected by vasoactive agents and fluid resuscitation. One animal had intraoperative cardiac arrest and was resuscitated by heart massage. Fifteen experimental animals were raised for 6 months and all survived.

  Conclusion  The selection of suitable experimental animals like swine and well-established surgical methods could ensure the success establishment of experimental models and patch repairment.